Title of Invention	A FLAME RETARDANT COMPOSITION FOR MESH SHEETS AND A FLAMEPROOF MESH SHEET MADE THEREWITH
Abstract	The present invention relates to a flame retardant composition for mesh sheets which comprises 40 to 130 parts by weight of an ammoniurrfpolyphosphate compound and 60 to 150 parts by weight of a metal hydroxide selected from magnesium hydroxide and/or aluminum hydroxide based on 100 parts by weight of the solid content of an aqueous dispersion of an ethylene base copolymer having a resin solid content of 25 to 75 wt%.The present invention also relates to a flameproof mesh sheet of woven coated yarn.

Title of Invention

A FLAME RETARDANT COMPOSITION FOR MESH SHEETS AND A FLAMEPROOF MESH SHEET MADE THEREWITH

Abstract

The present invention relates to a flame retardant composition for mesh sheets which comprises 40 to 130 parts by weight of an ammoniurrfpolyphosphate compound and 60 to 150 parts by weight of a metal hydroxide selected from magnesium hydroxide and/or aluminum hydroxide based on 100 parts by weight of the solid content of an aqueous dispersion of an ethylene base copolymer having a resin solid content of 25 to 75 wt%.The present invention also relates to a flameproof mesh sheet of woven coated yarn.

Full Text	[Detailed Description of the Invention] [0001] [Field of the Invention] The present invention relates to a halogen-free flameproof mesh sheet used outdoors such as in a construction work site or engineering work site for a long time. [0002] [Prior Art] A tendency toward an increase in the number of buildings having a large number of stories is lately seen in the construction industry. Meanwhile, there is an increase in the number of houses having a small number of stories. It is obligatory to lay flameproof mesh sheets, flameproof mesh sheets for houses having a small number of stories and scattering prevention flameproof mesh sheets in tliese buildings for safety and regulations are becoming more and more strict. Currently used flameproof mesh sheets and scattering prevention flameproof mesh sheets are produced by weaving gray yarn prepared by coating polyester, nylon or polypropylene multi-filament fibers with a vinyl chloride-based paste resin composition and heating, and heating the obtained gray cloth, or by coating gray cloth prepared by weaving multi-filament fibers with a vinyl chloride-based paste resin composition and heating, and processing the obtained gray cloth to a desired shape. The resin composition for coating fibers and cloth comprises a chlorine-containing vinyl chloride resin as a resin and a chlorine-based flame retardant such as chlorinated paraffin, bromide-based flame retardant such as decabromodiphenyl oxide, or inorganic flame retardant such as antimony trioxide as a flame retardant (Examined Japanese Patent Publication Nos. 52-41786, 53-18065 and 61-9430, Plastics, February, 1991). In recent years, it has been globally demanded to avoid the use of resins and flame retardants containing elemental halogen which generates harmful gas at the time of combustion from the viewpoint of environmental preservation. Japanese Laid-open Patent Application No. 61-223045 proposes that red phosphorus and ammonium phosphate are kneaded into a polyolefin to prevent corrosion by halogen contained in a halogen-containing compound flame retardant. However, there is unknown a flame retardant prepared by dispersing ammonium polyphosphate or a metal hydroxide into an aqueous dispersion of an ethylene-vinyl acetate copolymer, an ethylene-vinyl acetate-vinyl versatate copolymer or an ethylene-vinyl acetate-acrylic ester copolymer, or a dispersion consisting of the above dispersion and .a polyurethane aqueous dispersion. The inventor of the present invention previously proposed a halogen-free flame retardant comprising an aqueous dispersion of a polyolefin resin. Although,this flame retardant provides an excellent effect, a tendency toward an increase in its viscosity during storage by time changes is seen. The present inventor also proposed plreviously a halogen-free flame retardant containing an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 parts by weight of vinyl acetate and the balance consisting of ethylene as Japanese Laid-open Patent Application No. 9-312550. Although this flame retardant provides excellent function and effect, a product thereof has a red tint because red phosphorus is used and it is difficult to color it opaque white or light -vivid color even by adding titanium oxide or the like. The present invention improves the color and flame retardancy of this invention. An opaque white or light vivid color flameproof mesh sheet has been desired according to application field. [0003] [Problem to Be Solved by the Invention] It is an object of the present invention which has been made in view of the above situation to provide a flame retardant for halogen-free flameproof mesh sheets which does not experience an increase in viscosity during storage, can be colored any color, is lustrous and flexible, and does not generate harmful halogen gas at the time of combustion as well as a flameproof mesh sheet comprising the same. [0004] [Means for Solving the Problem] The present invention relates to: 1. A flame retardant for mesh sheets which comprises 40 to 130 parts by weight of an ammonium polyphosphate compound and 60 to 150 parts by weight of a metal hydroxide based on IdO parts by weight of the solid content of a polyolefin resin aqueous dispersion having a resin solid content of 25 to 75 wt%. 2. The flame retardant for mesh sheets according to claim 1, wherein the polyolefin resin aqueous dispersion is at least one selected from an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate. having a resin solid content of 30 to 70 wt%, and an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%. 3. The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 part by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content 4. The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content, 5. The flame retardant for mesh sheet according to claim 1 or 2 Which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content. 6 . The flame retardant for mesh sheets according to any one of claims 1 to 5, wherein the ammonium polyphosphate compound is microcapsulated. 7- The flame retardant for mesh sheets according to any one of claims 1 to 6, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide. 8. A flame retardant for mesh sheets which is prepared by blending 3 to 30 parts by weight of an organic phosphoric ester with the flame retardant for mesh sheets according to any one of claims 1 to 7 based on 100 parts by weight of the solid content of the aqueous dispersion resin of the flame retardant. 9. The flame retardant for mesh sheets according to ::laim 8, wherein the organic phosphoric ester is a halogen- free phosphoric ester. 10. A flameproof mesh sheet woven of coated yarn prepared by coating multi-filament fibers with the flame retardant for mesh sheets of any one.of clams 1 to 9 through impregnation and heating. 11. The flameproof mesh sheet according to claim 10, wherein the multi-filament fibers have an equivalent single fineness of 3 to 17 denier, a total fineness of 500 to 4,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %. 12. A flameproof mesh sheet prepared by coating mesh sheet cloth woven of multi-filament fibers with the flame retardant for mesh sheets of any one of claims 1 to 9 through impregnation and heating. 13. The flameproof mesh sheet according to claim 12, wherein the mesh sheet cloth woven of multi-filament fibers is prepared by plain weaving synthetic fibers having:an equivalent single fineness of 2 to 13 denier, a total fineness of 150 to 2,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %, or by paralleling 2 to 4 fibers and leno weaving or imitation gauging them with a loom, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm, 14. Flameproof mesh sheet cloth woven of multi¬ filament fibers coated with 60 to 500 parts by weight of the flame retardant for mesh sheets according to any one of claims 1 to 8 through impregnation based on 100 parts by weight of the mesh sheet cloth woven of multi-filament fibers or multi-filaments. [0005] [Description of the Preferred Embodiments] The reason for the; use of an aqueous dispersion of an ethylene-vinyl acetate copolymer which is an olefin resin, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer or an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer as a base material in the present invention is to fully impregnate multi-filament fibers and cloth with a flame retardant to uniformly coat them with the flame retardant. The aqueous dispersion makes easy coating by impregnation. The ethylene-vinyl acetate copolymer used in the present invention is preferably a copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene. The aqueous dispersion of the ethylene-vinyl acetate copolymer preferably has a solid content of 25 to 75 wt%, a particle diameter of 0.1 to 15 pm, a viscosity of 50 to 9,000 cp and a pH of 4 to 9, as exemplified by V-200 and V-100 (of Mitsui Petrochemical Industries, Ltd.), and S-200, S-467, S-500, S-706, S-455, S-752 and S-753 (of Sumitomo Chemical Company, Ltd. ) . Since the ethylene-vinyl acetate copolymer has a -OCO-CH3 group and contains a lot of oxygen, the flame retarding effect thereof is large when it is used in combination of ammonium polyphosphate. The ethylene-vinyl acetate-vinyl versatate copolymer used in the present invention is preferably a copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75- wt% of vinyl versatate. The aqueous dispersion of the copolymer preferably has a solid content of 30 to 70 wt%, a particle diameter of 0.1 to 15 \|im, a viscosity of 50 to 3,000 cp and a pH of 4 to 9, as exemplified by S-950 and S-951 (of Sumitomo Chemical Company, Ltd.), Since the ethylene-vinyl acetate-vinyl versatate copolymer also has a -OCO-CH3 group and a barsatic acid group, R1R2R3C-0C0-CH=CH2, and contains a lot of oxygen, the flame retarding effect thereof is large when it is used in combination of ammonium polyphosphate. [0006] The ethylene-vinyl acetate-acrylic ester copolymer used in the present invention is preferably a copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester. The aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer preferably has a solid content of 25 to 75 wt%, a particle diameter of 0.1 to 15 pm, a viscosity of 50 to 9,000 cp and a pH of 4 to 9, as exemplified by Polysol EF-421 and Polysol EF-221 (of Showa Kobunshi Co., Ltd.) and Sumiflex S-900, S-910 and S-920 (of Sumitomo Chemical Company, Ltd.). Since the ethylene-vinyl acetate-acrylic ester copolymer has a -OCO-CH3 group and -COOH group and contains a lot of oxygen as well, the flame retarding effect thereof is large when it is used in combination of ammonium polyphosphate. [0007] A polyurethane having the main structure of a polyester, polyether or polycarbonate is used as the polyurethane. A polyurethane having the main structure of a polyester is preferred from the viewpoints of flexibility, water ; resistance, adhesion and the like. The polyurethane aqueous dispersion used in the present invention preferably has a solid content of 25 to 70 wt%, a particle diameter of 0.01 to 10 pm, a viscosity of 10 to 3,000 cp and a pH of 4 to 9, as exemplified by Despacol U-42 and Despacol KA8481 of Sumitomo Viel Urethane Co., Ltd., Adecabontiter HUX-380, Adecabontiter HUX-232, Adecabontiter HUX-290H, Adecabontiter HUX-350 and Adecabontiter HUX-386H of Asahi Denka Kogyo K.K. and Letan WB of Kansai Paint Co., Ltd. [0008] The ammonium polyphosphate compound used in the present invention is ammonium polyphosphate or amide polyphosphate. By using the microcapsulated ammonium polyphosphate compound, an increase in the viscosity of an aqueous dispersion can be reduced when the ammonium polyphosphate compound is mixed into an olefin aqueous dispersion resin. Further, the flameproof mesh sheet is detached and washed to remove dirt after it is laid at a construction site and used for 4 to 8 months. It is washed by immersing in hot water heated at about 40"C and containing a detergent for several hours. The ammonium polyphosphate compound can be made hardly soluble in water and stable by microcapsulation. The ammonium polyphosphate compound has a phosphorus content of 15 to 35 % and an average particle diameter of 5 to 40 pm. The flame retardant of the present invention contains 40 to 130 parts by weight of an ammonium polyphosphate compound based on 100 parts by weight of the total resin solid content. When the amount of the ammonium polyphosphate compound is smaller than 40 parts by weight, the flame retarding effect thereof is small and when the amount is larger than 130 parts by weight, there is almost no improvement of the flame retarding effect. Therefore, it is not necessary to add a large amount of the ammonium polyphosphate compound. [0009] The flame retardant of the present invention comprehends a flame retardant which contains 3 to 30 parts by weight of an organic phosphoric ester based on 100 parts by weight of the total resin solid content. When the amount of the organic phosphoric ester is smaller than 3 parts by weight, the effect of improving flame retardancy is small and the improvement of luster and flexibility is small and when the amount is larger than 30 parts by weight, the improvement of flame retardancy is small and the final product becomes sticky disadvantageously. The organic phosphoric ester is preferably a phosphoric ester containing no halogen and having an elemental phosphorus content of 7 to 18 wt% and a viscosity (20" C) of 10 to 150 cp. The organic phosphoric ester used in the present invention is preferably allyl phosphate-based because it has a flame retarding effect, compatibility with a resin and a platioialng effect. pi 0.5 tic; z.ii^ [0010] When an ammonium polyphosphate compound is used as a flame retardant in the present invention, the ammonium polyphosphate compound thermally decomposes at the time of combustion and generates nitrogen gas which shut off oxygen. The ammonium polyphosphate compound promotes the carbonization of a polyolefin as a dehydration carbonization catalyst while it generates nitrogen-containing gas, thereby improving a flame retarding effect. When a polyolefin and a polyurethane are used in combination, the blending ratios of these to the ammonium polyphosphate and the organic phosphoric ester are based on 100 parts by weight of the total resin solid content. [0011] When a metal hydroxide is further blended, a larger flame retarding effect is obtained advantageously. Preferred examples of the metal hydroxide include magnesium hydroxide, aluminum hydroxide, red phosphorus and ammonium polyphosphate from the viewpoint of a multiplication effect. When a metal hydroxide is blended, the obtained product becomes hard but the phosphoric ester softens the product, thus preventing it from becoming hard advantageously. The metal hydroxide must be existent in an amount of 60 to 150 parts by weight based on 100 parts by weight of the total resin solid content of the polyolefin and the polyurethane, When the amount of the metal hydroxide is smaller than-60 parts by weight based on 100 parts by weight of the total resin solid content, its effect of promoting flame retardancy is small. When the amount is larger than 150 parts by weight, the viscosity of the aqueous dispersion of the ethylene-vinyl acetate copolymer rises disadvantageously. [0012] As the aluminum hydroxide, for example, Hijilite H-42M and Hijilite H-43M (of Showa Denko K.K.) are used. As the magnesium hydroxide, for example, Kismer 5A (of Kyowa Kagaku Kogyo Co., Ltd.) is used. [0013] A description is subsequently given of a flameproof mesh sheet comprising the flame retardancy of the present invention. The multi-filament fiber used in the present invention is one or more multi-filament fibers selected from polyester, nylon, polypropylene, polyethylene and vinylon fibers. A polyester fiber is preferred from the viewpoints of strength and heat shrinkage. The tensile strength of the multi-filament fiber is adjusted to 4 to 10 g/denier to increase the strength and reduce the weight of a flameproof mesh sheet, and the breaking extension thereof is adjusted to 14 to 45 % to increase the toughness of a flameproof mesh sheet and improve the drop impact energy absorption thereof. The multi-filament fiber has an equivalent single fineness of 3 to 17 denier, preferably 3 to 12 denier, particularly preferably 4 to 9 denier and a total fineness of 500 to 4,500 denier, preferably 1,000 to 3,500 denier, particularly preferably 1,500 to 3,000 denier. [0014] The multi-filament fiber used in cloth treated with a flame retardant after weaving has an equivalent single fineness of 2 to 13 denier, preferably 2 to 11 denier, particularly preferably 2.5 to 9 denier and a total fineness of 150 to 2,500 denier, preferably 200 to 2,000, particularly preferably 250 to 1,500 denier. The tensile strength of the multi-filament fiber is controlled to 4 to 10 g/denier to increase the strength and reduce the weight of a flameproof mesh sheet, and the breaking extension thereof is controlled to 14 to 45 % to increase the toughness of a flameproof mesh sheet and improve the drop impact energy absorption thereof. A flameproof mesh sheet which must have high strength and high toughness is prepared by paralleling 2 to 4 multi¬filament fibers and leno weaving or imitation gauging the fibers with a loom. In the case of a scattering prevention flameproof mesh sheet, cloth is often made by plain weaving a single multi-filament fiber with a loom. In the case of a flameproof mesh sheet for houses having a small number of stories, cloth is often made by plain weaving or leno weaving 2 to 4 multi-filament fibers. The mesh length is preferably 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm. [0015] As for the weight ratio of the solid content of the flame retardant to the multi-filament fiber and cloth, the solid content of the flame retardant is 60 to 500 parts by weight based on 100 parts by weight of the multi-filament fiber and cloth. When the solid content of the flame retardant is smaller than 60 parts by weight based on 100 parts by weight of the multi-filament fiber or cloth, coating nonuniformity occurs and part of the texture of the rtiulti-filament fiber and cloth is exposed, thereby deteriorating appearance and reducing weatherability. Flameproofness also deteriorates» When the solid content is larger than 500 parts by weight, the obtained flameproof mesh sheet becomes heavy, thereby deteriorating handling properties disadvantageously, [0016] In the present invention, the types and amounts of a pigment, dye, plasticizer, ultraviolet absorber, optical stabilizer, antioxidant, stabilizer, coupling agent, defearning agent, dispersant, diluent, thickener, foaming agent, mildewproofing agent and the^TI)ce~~aH"'Tujrta^ selected and used in conjunction with the flame retardant, A description is subsequently given of a process for producing the flameproof mesh sheet of the present invention. When the flameproof mesh sheet of the present invention is produced using multi-filament fibers, the fibers are coated with a flame retardant through a sizing nozzle, and the leated and gelled coated yarn is taken up by a winder. The ::oated yarn taken up by the winder is woven by a loom. The ibtnlnnd fnbrlo In int.ro(lu(^.od .lnt.o a hnntlng furnaco nnd leated to carry out i-'to obtain gray cloth. ^^^ f^x;^ u^sk The gray cloth is cut to a predetermined size, sewed ind subjected to ^;^ ev^jeCS Processing to obtain a halogen-:ree flameproof mesh sheet. [0017] When the flameproof mesh sheet of the present invention Ls produced using cloth, multi-filament fibers are woven with 1 dobby loom to obtain gray cloth. After the gray cloth is Immersed in a tank filled with a flame retardant for mesh ;heets and passed through the tank, it is dried with an air )low and introduced into a heating furnace to carry out heat [elation to obtain coated gray cloth. To increase the amount >f the flame retardant coated on the cloth, the cloth is mmersed in and passed through the tank filled with the flame etardant at least two times to produce coated gray cloth, he cloth is cut to a predetermined size, sewed and subjected -f; X e/€. leti> o non 9hlftin-g processing to obtain a halogen-free lameproof mesh sheet. [0018] [Examples] The following examples are given to further illustrate he present invention. Excunple 1 200 parts by weight of the S-753 ethylene-vinyl acetate copolymer aqueous dispersion(of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) was charged into a planetary mixer (volume of 25 liters), and then 80 parts by weight of the Fostaphram AP-462 ammonium polyphosphate (of Hoechst Co., Ltd.), 120 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.), 0.8 part by weight of the Tinubin 327 ultraviolet absorber (of Ciba Geigy Co., Ltd.), 0.8 part by weight of the Irganox 1010 antioxidant (of Ciba Geigy Co., Ltd.), 1.0 part by weight of the HALS optical stabilizer (of Ciba Geigy Co., Ltd.), 2 parts by weight of the TIPAQUE C-97 titanium oxide (of Ishihara Sangyo Co., Ltd.) and 30 parts by weight of water were added little by little to the mixer under agitation over about 5 minutes. Agitation was further continued for 20 minutes. The pressure was gradually reduced to 5 mmHg and vacuum defoaming was carried out for about 30 minutes to give a flame retardant for mesh sheets having a viscosity of 3,530 cp (BM type viscometer, rotor V-6, 12 rpm, 25°C). The flame retardant was placed in a bath, polyester multi-filament fibers having a total fineness of 1,750 denier, each consisting of 384 filaments with an equivalent single fineness of 4.5 denier, a tensile strength of 8.5 g/denier and a breaking extension of 21 %, were passed through a guide, pinched with a pinch roll, passed through a guide roll, the bath of the flame retardant and a sizing nozzle (of 0.7 mm in diameter) to coat the multi-filament fibers, and the obtained strand was heated at 170'C in a heating furnace and passed through a another sizing nozzle (of 0.8 mm in diameter) to coat the strand, and then heated at 190'C in a heating furnace to produce coated yarn of 3,980 denier. The weight ratio of the flame retardant for mesh sheets to the multi-filament fibers of the coated yarn was 130/100. Plain weave cloth having a mesh length of 52 warps/10 cm and 52 wefts/10 cm was woven of the coated yarn with a rapier loom at a speed of 50 cm/min. Thereafter, this cloth was heated at 170'C by passing through a heating furnace to thermally fuse intersections between warps and wefts to obtain the flameproof mesh sheet of the present invention. The gray cloth was cut to a width of 190 cm and a length of 520 cm, sewed with a sewing machine and subjected to non- e/e,lets " shifting processing to obtain a 180 cm wide, 510 cm long flameproof mesh sheet. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of a flameproof mesh sheet treated with the flame retardant are shown in Table 3. [0019] Example 2 182 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd.) was used in place of the S-753 ethylene-vinyl acetate copolymer. The TIPAQUE C-97 titanium oxide was not added. A flame retardant having a viscosity of 2,640 cp was obtained in the same manner as in Example 1 except above. Multi-filament fibers having a total fineness of 3,000 denier, each consisting of 384 filaments with an equivalent single fineness of 7.8 denier, were passed through a sizing nozzle of 0.8 mm in diameter, gelled by heating, passed through a sizing nozzle of 0.9 mm in diameter and gelled by heating to obtain coated yarn of 5,815 denier, A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the coated yarn was processed into 30 warps/10 cm and 30 wefts/10 cm. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of a flameproof mesh sheet treated with the flame retardant are show in Table 3. [0020] Example 3 182 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) was used in place of the S-753 ethylene-vinyl acetate copolymer. 55 parts by weight of; the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation), 15 parts by weight of the TCP organic phosphoric ester and 140 parts by weight of the Kismer 5A magnesium hydroxide (of Kyowa Kagaku Co., Ltd.) were used. Further, 8 parts by weight of the TIPAQUE C-97 titanium oxide was added. A flame retardant having a viscosity of 2,980 cp was obtained in the same manner as in Example 1 except above. Coated yarn of 8,852 denier was obtained using this flame retardant, the same multi-filament fibers as in Example 1, a sizing nozzle of 0.8 mm in diameter for the first coating and a sizing nozzle of 1.0 mm in diameter for the second coating. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was obtained in the same manner as in Example 1 except that this flame retardant was used. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 3. [0021] Example 4 80 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 55 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%), and 55 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) were used. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 3. [0022] Example 5 55 parts by weight of the S-500 (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) and 60 parts by weight of the S-752 (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) in place of the S753 ethylene-vinyl acetate copolymer, 105 parts by weight of the Adecabontiter HUX-380 polyurethane (of Asahi Denka Kogyo Co., Ltd.,; the ;nain structure of a polyester, a solid content of 38 wt%), 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation), 5 parts by weight of the TOP organic phosphoric ester (of Daihachi Kagaku Co., Ltd.), and 100 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.) were used. Water was not further added. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above. Multi-filament fibers of 1,500 denier were coated only once using a sizing nozzle of 0,7 mm in diameter. Coated yarn of 3,327 denier was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the coated yarn was processed into 25 warps/10 cm and 25 wefts/10 cm. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 3. [0023] Example 6 145 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 53 parts by weight of the Adecabontiter HUX-380 polyurethane (of Asahi Denka Kogyo Co./ Ltd., the main structure of a polyester, a solid content of 38 wt%), 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation) and 120 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.) were added. Water was not further added. A flame retardant for mesh sheets having a viscosity of 2,820 cp was obtained in the same manner as in Example 1 except above. A flame retardant for mesh sheets was obtained in the same manner as in Example 1 except that the flame retardant was used. The composition of the flame retardant is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 4. [0024] Example 7 91 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene- vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 132 parts by weight of the Letan WB polyurethane (of Kansai Paint Co., Ltd., the main structure of a polyester, a solid content of 38 wt%) and 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation) were used. Water was not further add^d. A flame retardant for mesh sheets having a viscosity of 1,950 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 4. [0025] Example 8 91 parts by weight of the S-500 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) and 100 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) were used in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%). Water was not further added. A flame retardant for mesh sheets having a viscosity of 1,820 cp was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2. Imitation gauze cloth having a mesh length of 45 warps/10 cm and 45 wefts/10 cm was woven with a dobby loom using the flame retardant for mesh sheets and without using the coated multi-filament fibers in Example 1 by paralleling 3 multi-filament fibers of 750 denier to coat the cloth. The weight of the cloth was 225 g/m^. The cloth was passed through a guide roll and a roll coater filled with the flame retardant, squeezed with a squeezing roll, dried with an air blow to remove the flame retardant filling the meshes of the cloth, and gelled in a heating furnace at 130"C, 160"C and 180'C. The coated gray cloth was taken up by a winder. The weight of the coated gray cloth was 482 g/m^ (mesh sheet gray cloth). The gray cloth was cut to a predetermined size, sewed and subjected to non ohifting processing to obtain a flameproof mesh sheet. The performance of the mesh sheet is shown in Table 4. [0026] Example 9 Plain weave cloth having a mesh length of 120 warps/10 cm and 120 wefts/10 cm was woven of multi-filament fibers of 250 denier with a loom without coating the multi-filament fibers as in Example 8. The weight of the cloth was 66 g/m^. The cloth was coated with the same flame retardant for mesh sheets as in Example 8 in the same manner as in Example 8 and yelled by heating, and the coated gray cloth having a weight of 134 g/m^ was taken up by a winder. The gray cloth was cut to a predetermined size, sewed and subjected to non-shifting processing to obtain a 1/ flameproof mesh sheet for houses having a small number of stories . The composition of the flame retardant used is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet for houses having a small number of stories treated with the flame retardant are shown in Table 4 [0027] Example 10 145 parts by weight of the S-500 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) and 53 parts by weight of the Letan WB polyurethane (of Kansai Paint Co., Ltd., a solid content of 38 wt%) were used. A flame retardant for mesh sheets having a viscosity of 1,960 cp was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2. The same cloth as in Example 9 was coated with the flame retardant for mesh sheets in the same manner as in Example 9, and the obtained coated gray cloth having a weight of 155 g/m^ was taken up by a winder. The gray cloth was cut to a predetermined size, sewed and subjected to non ghifting processing to obtain a flameproof mesh sheet for houses having a small number of stories. The measurement results of the performance of the flameproof mesh sheet for houses having a small number of stories are shown in Table 4. [0028] Comparative Example 1 The amount of the AP-462 Fostaphram ammonium polyphosphate (of Client Japan Co., Ltd.) used in Example 1 was changed to 30 parts by weight. A flame retardant having a viscosity of 2,310 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 1. The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7. [0029] Comparative Example 2 The amount of the AP-462 Fostaphram ammonium polyphosphate (of Client Japan Co., Ltd.) used in Example 1 was changed to 150 parts by weight. A flame retardant having a viscosity of 2,880 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 1. The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7. [0030] Comparative Example 3 The amount of the Kismer-5 magnesium hydroxide (of Kyowa Kagaku Kogyo Co., Ltd.) used in Example 3 was changed to 50 parts by weight. A flame retardant having a viscosity of 2,360 cp was obtained in the same manner as in Example 3 except above. A flameproof mesh sheet was produced using the flcime retardant in the same manner as in Example 3. The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7. [0031] * Comparative Example 4 The amount of the Hijilite H-42H aluminum hydroxide (of Showa Denko K.K.) used in Example 6 was changed to 170 parts iby weight. A flame retardant having a viscosity of 3,270 cp was obtained in the same manner as in Example 6 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 6. The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7. [0032] Comparative Example 5 A sizing nozzle of 0.6 mm in diameter was used in place of the sizing nozzle of 0.7 mm in diameter used in Example 1 A flameproof mesh sheet having a weight of 346 g/m^ was produced by coating and heating in the same manner as in Example 8 except that the flame retardant aqueous dispersion was used and the same cloth as in Example 8 was used. The composition of the flame retardant is shown in Table 6 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 8. (Notes) ® expressed in parts by weight based on 100 parts by weight of the resin solid content. The unit of values of the coated cloths of Examples 8, 9 and 10 is g/im^. The finenesses and numbers of filaments of multi-filament fibers for the cloths of Examples 8, 9 and 10 are 750 denier x 3, 250 denier x 1, and 250 denier x 1, respectively. (§) The combustion test of Examples 5, 7, 9 and 10 is based on A-1 method in which heating is carried out for 1 minute and fire is caught after 3 seconds. A is TERRAJU-60 (of Chisso Corporation). (D B is Fostaphram AP462 (of Client Japan Co., Ltd.). (7) C is Hijilite H-42M (of Showa Denko K.K.). (8) D is Kismer 5A (of Kyowa Kagaku Co., Ltd.). ® The columns of the fineness (De) of the coated yarn and the coated cloth are for coated cloth in Examples 8, 9 and 10 and coated yarn in other examples. [0044] Methods for measuring properties 1. viscosity measurement method DM type viscometer, rotor No. 6, revolution of 12 rpm. 25* C 2. combustion test based on JIS L-1091 A-1 method (45'C, micro-burner method) A-2 method (45" C, meckel burner method) D method (number of times of flame contact) 3. tensile strength test measured based on JIS L-1068 4. analysis of combustion gas (1) combustion gas generation method tubular electric furnace method: based on JIS K 2541 combustion temperature: SSOilC C amount of sample: 0.3 g air flow rate: 1,000 ml/min (2) detection method hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen fluoride (HF): detected by ion chromatography after treated based on JIS K 0107 5. drop impact strength (penetration test) measured based on JIS-8952. A steel tube having an outer diameter of 48,6 nun, a thickness of 2.5 mm and a weight of 2,7 kg was used in this test in the case of a flameproof mesh sheet for houses having a small number of stories and scattering prevention flameproof mesh sheet, 6. flexibility excellent (soft) @ good O slightly good D slightly bad (hard) A bad X sticky X X 7 . color difference (1) manufacturer: DATA COLOR INTERNATIONAL LTE (2) type: SPECTRA FLASH SF-600 (3) measurement method: DE (whiteness) and DL (brightness) of a sample piece are measured using a white substrate as a reference. (4) preparation of sample piece: After a flame retardant for mesh sheets is poured into a 10 cm wide, 15 cm long and 1 mm deep SUS frame, the flame retardant for mesh sheets above the top of the SUS frame is removed by a SUS bar, the other flame retardant is heated in a heating furnace at 150** C for 5 minutes, and then the sample piece is taken out to prepare a sample piece. [0045] (Effect of the Invention] The flameproof mesh sheet of the present invention is excellent in flame retardancy and satisfactory in terms of drop impact strength without generating harmful halogen gas at the time of combustion. [Type of the Document] Specification [Title of the Invention] FLAME RETARDANT FOR MESH SHEETS AND FLAMEPROOF MESH SHEET COMPRISING THE SAME [Claim 1] A flame retardant for mesh sheets which comprises 40 to 130 parts by weight of an ammonium polyphosphate compound and 60 to 150 parts by weight of a metal hydroxide based on 100 parts by weight of the solid content of a polyolefin resin aqueous dispersion having a resin solid content of 25 to 75 wt%. [Claim 2] The flame retardant for mesh sheets according to claim 1, wherein the polyolefin resin aqueous dispersion is at least one selected from an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, and an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%. [Claim 3] The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 part by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content [Claim 4] The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content. [Claim 5] The flame retardant for mesh sheet according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content. [Claim 6] The flame retardant for mesh sheets according to any one of claims 1 to 5, wherein the ammonium polyphosphate compound is microcapsulated. [Claim 7] The flame retardant for mesh sheets according to any one of claims 1 to 6, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide. [Claim 8] A flame retardant for mesh sheets which is prepared by blending 3 to 30 parts by weight of an organic phosphoric ester with the flame retardant for mesh sheets according to any one of claims 1 to 7 based on 100 parts by weight of the solid content of the aqueous dispersion resin of the flame retardant. [Claim 9] The flame retardant for mesh sheets according to claim 8, wherein the organic phosphoric ester is a halogen-free phosphoric ester. [Claim 10] A flameproof mesh sheet woven of coated yarn prepared by coating multi-filament fibers with the flame retardant for mesh sheets of any one of clams 1 to 9 through impregnation and heating. [Claim 11] The flameproof mesh sheet according to claim 10, wherein the multi-filament fibers have an equivalent single fineness of 3 to 17 denier, a total fineness of 500 to 4,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %. [Claim 12] A flameproof mesh sheet prepared by coating mesh sheet cloth woven of multi-filament fibers with the flame retardant for mesh sheets of any one of claims 1 to 9 through impregnation and heating. [Claim 13] The flameproof mesh sheet according to claim 12, wherein the mesh sheet cloth woven of multi-filament fibers is prepared by plain weaving synthetic fibers having an equivalent single fineness of 2 to 13 denier, a total fineness of 150 to 2,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %, or by paralleling 2 to 4 fibers and leno weaving or imitation gauging theni with a loom, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm. [Claim 14] Flameproof mesh sheet cloth woven of multi¬filament fibers coated with 60 to 500 parts by weight of the flame retardant for mesh sheets according to any one of claims 1 to 8 through impregnation based on 100 parts by weight of the mesh sheet cloth woven of multi-filament fibers or multi-filaments. lb. A flsme retardant for mesh sheets/ substantially as hereinabove described and exemplified.

Full Text

[Detailed Description of the Invention]
[0001]
[Field of the Invention]
The present invention relates to a halogen-free flameproof mesh sheet used outdoors such as in a construction work site or engineering work site for a long time.
[0002]
[Prior Art]
A tendency toward an increase in the number of buildings having a large number of stories is lately seen in

the construction industry. Meanwhile, there is an increase in the number of houses having a small number of stories. It is obligatory to lay flameproof mesh sheets, flameproof mesh sheets for houses having a small number of stories and scattering prevention flameproof mesh sheets in tliese buildings for safety and regulations are becoming more and more strict.
Currently used flameproof mesh sheets and scattering prevention flameproof mesh sheets are produced by weaving gray yarn prepared by coating polyester, nylon or polypropylene multi-filament fibers with a vinyl chloride-based paste resin composition and heating, and heating the obtained gray cloth, or by coating gray cloth prepared by weaving multi-filament fibers with a vinyl chloride-based paste resin composition and heating, and processing the obtained gray cloth to a desired shape.
The resin composition for coating fibers and cloth comprises a chlorine-containing vinyl chloride resin as a resin and a chlorine-based flame retardant such as chlorinated paraffin, bromide-based flame retardant such as decabromodiphenyl oxide, or inorganic flame retardant such as antimony trioxide as a flame retardant (Examined Japanese Patent Publication Nos. 52-41786, 53-18065 and 61-9430, Plastics, February, 1991).
In recent years, it has been globally demanded to avoid the use of resins and flame retardants containing elemental halogen which generates harmful gas at the time of combustion

from the viewpoint of environmental preservation.
Japanese Laid-open Patent Application No. 61-223045 proposes that red phosphorus and ammonium phosphate are kneaded into a polyolefin to prevent corrosion by halogen contained in a halogen-containing compound flame retardant. However, there is unknown a flame retardant prepared by dispersing ammonium polyphosphate or a metal hydroxide into an aqueous dispersion of an ethylene-vinyl acetate copolymer, an ethylene-vinyl acetate-vinyl versatate copolymer or an ethylene-vinyl acetate-acrylic ester copolymer, or a dispersion consisting of the above dispersion and .a polyurethane aqueous dispersion.
The inventor of the present invention previously proposed a halogen-free flame retardant comprising an aqueous dispersion of a polyolefin resin. Although,this flame retardant provides an excellent effect, a tendency toward an increase in its viscosity during storage by time changes is seen.
The present inventor also proposed plreviously a halogen-free flame retardant containing an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 parts by weight of vinyl acetate and the balance consisting of ethylene as Japanese Laid-open Patent Application No. 9-312550. Although this flame retardant provides excellent function and effect, a product thereof has a red tint because red phosphorus is used and it is difficult to color it opaque white or light -vivid color even by adding titanium oxide or

the like. The present invention improves the color and flame retardancy of this invention. An opaque white or light vivid color flameproof mesh sheet has been desired according to application field.
[0003]
[Problem to Be Solved by the Invention]
It is an object of the present invention which has been made in view of the above situation to provide a flame retardant for halogen-free flameproof mesh sheets which does not experience an increase in viscosity during storage, can be colored any color, is lustrous and flexible, and does not generate harmful halogen gas at the time of combustion as well as a flameproof mesh sheet comprising the same.
[0004]
[Means for Solving the Problem]
The present invention relates to:
1. A flame retardant for mesh sheets which comprises 40 to 130 parts by weight of an ammonium polyphosphate compound and 60 to 150 parts by weight of a metal hydroxide based on IdO parts by weight of the solid content of a polyolefin resin aqueous dispersion having a resin solid content of 25 to 75 wt%.
2. The flame retardant for mesh sheets according to claim 1, wherein the polyolefin resin aqueous dispersion is at least one selected from an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a

resin solid content of 25 to 75 wt%, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate. having a resin solid content of 30 to 70 wt%, and an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%.
3. The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 part by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content
4. The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150

parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content,
5. The flame retardant for mesh sheet according to claim 1 or 2 Which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content.
6 . The flame retardant for mesh sheets according to any one of claims 1 to 5, wherein the ammonium polyphosphate compound is microcapsulated.
7- The flame retardant for mesh sheets according to any one of claims 1 to 6, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide.
8. A flame retardant for mesh sheets which is prepared by blending 3 to 30 parts by weight of an organic phosphoric ester with the flame retardant for mesh sheets according to any one of claims 1 to 7 based on 100 parts by weight of the solid content of the aqueous dispersion resin of the flame retardant.
9. The flame retardant for mesh sheets according to ::laim 8, wherein the organic phosphoric ester is a halogen-

free phosphoric ester.
10. A flameproof mesh sheet woven of coated yarn prepared by coating multi-filament fibers with the flame retardant for mesh sheets of any one.of clams 1 to 9 through impregnation and heating.
11. The flameproof mesh sheet according to claim 10, wherein the multi-filament fibers have an equivalent single fineness of 3 to 17 denier, a total fineness of 500 to 4,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %.
12. A flameproof mesh sheet prepared by coating mesh sheet cloth woven of multi-filament fibers with the flame retardant for mesh sheets of any one of claims 1 to 9 through impregnation and heating.
13. The flameproof mesh sheet according to claim 12, wherein the mesh sheet cloth woven of multi-filament fibers is prepared by plain weaving synthetic fibers having:an equivalent single fineness of 2 to 13 denier, a total fineness of 150 to 2,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %, or by
paralleling 2 to 4 fibers and leno weaving or imitation gauging them with a loom, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm,
14. Flameproof mesh sheet cloth woven of multi¬
filament fibers coated with 60 to 500 parts by weight of the
flame retardant for mesh sheets according to any one of
claims 1 to 8 through impregnation based on 100 parts by

weight of the mesh sheet cloth woven of multi-filament fibers or multi-filaments.
[0005]
[Description of the Preferred Embodiments]
The reason for the; use of an aqueous dispersion of an ethylene-vinyl acetate copolymer which is an olefin resin, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer or an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer as a base material in the present invention is to fully impregnate multi-filament fibers and cloth with a flame retardant to uniformly coat them with the flame retardant. The aqueous dispersion makes easy coating by impregnation.
The ethylene-vinyl acetate copolymer used in the present invention is preferably a copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene. The aqueous dispersion of the ethylene-vinyl acetate copolymer preferably has a solid content of 25 to 75 wt%, a particle diameter of 0.1 to 15 pm, a viscosity of 50 to 9,000 cp and a pH of 4 to 9, as exemplified by V-200 and V-100 (of Mitsui Petrochemical Industries, Ltd.), and S-200, S-467, S-500, S-706, S-455, S-752 and S-753 (of Sumitomo Chemical Company, Ltd. ) .
Since the ethylene-vinyl acetate copolymer has a -OCO-CH3 group and contains a lot of oxygen, the flame retarding effect thereof is large when it is used in combination of ammonium polyphosphate. The ethylene-vinyl

acetate-vinyl versatate copolymer used in the present invention is preferably a copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75- wt% of vinyl versatate. The aqueous dispersion of the copolymer preferably has a solid content of 30 to 70 wt%, a particle diameter of 0.1 to 15 |im, a viscosity of 50 to 3,000 cp and a pH of 4 to 9, as exemplified by S-950 and S-951 (of Sumitomo Chemical Company, Ltd.),
Since the ethylene-vinyl acetate-vinyl versatate copolymer also has a -OCO-CH3 group and a barsatic acid group, R1R2R3C-0C0-CH=CH2, and contains a lot of oxygen, the flame retarding effect thereof is large when it is used in combination of ammonium polyphosphate.
[0006]
The ethylene-vinyl acetate-acrylic ester copolymer used in the present invention is preferably a copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester. The aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer preferably has a solid content of 25 to 75 wt%, a particle diameter of 0.1 to 15 pm, a viscosity of 50 to 9,000 cp and a pH of 4 to 9, as exemplified by Polysol EF-421 and Polysol EF-221 (of Showa Kobunshi Co., Ltd.) and Sumiflex S-900, S-910 and S-920 (of Sumitomo Chemical Company, Ltd.).
Since the ethylene-vinyl acetate-acrylic ester copolymer has a -OCO-CH3 group and -COOH group and contains a lot of oxygen as well, the flame retarding effect thereof is

large when it is used in combination of ammonium polyphosphate.
[0007]
A polyurethane having the main structure of a polyester, polyether or polycarbonate is used as the polyurethane. A polyurethane having the main structure of a polyester is preferred from the viewpoints of flexibility, water ; resistance, adhesion and the like.
The polyurethane aqueous dispersion used in the present invention preferably has a solid content of 25 to 70 wt%, a particle diameter of 0.01 to 10 pm, a viscosity of 10 to 3,000 cp and a pH of 4 to 9, as exemplified by Despacol U-42 and Despacol KA8481 of Sumitomo Viel Urethane Co., Ltd., Adecabontiter HUX-380, Adecabontiter HUX-232, Adecabontiter HUX-290H, Adecabontiter HUX-350 and Adecabontiter HUX-386H of Asahi Denka Kogyo K.K. and Letan WB of Kansai Paint Co., Ltd.
[0008]
The ammonium polyphosphate compound used in the present invention is ammonium polyphosphate or amide polyphosphate. By using the microcapsulated ammonium polyphosphate compound, an increase in the viscosity of an aqueous dispersion can be reduced when the ammonium polyphosphate compound is mixed into an olefin aqueous dispersion resin. Further, the flameproof mesh sheet is detached and washed to remove dirt after it is laid at a construction site and used for 4 to 8 months. It is washed by immersing in hot water heated at about 40"C and containing a detergent for several hours. The

ammonium polyphosphate compound can be made hardly soluble in water and stable by microcapsulation. The ammonium polyphosphate compound has a phosphorus content of 15 to 35 % and an average particle diameter of 5 to 40 pm.
The flame retardant of the present invention contains 40 to 130 parts by weight of an ammonium polyphosphate compound based on 100 parts by weight of the total resin solid content. When the amount of the ammonium polyphosphate compound is smaller than 40 parts by weight, the flame retarding effect thereof is small and when the amount is larger than 130 parts by weight, there is almost no improvement of the flame retarding effect. Therefore, it is not necessary to add a large amount of the ammonium polyphosphate compound.
[0009]
The flame retardant of the present invention comprehends a flame retardant which contains 3 to 30 parts by weight of an organic phosphoric ester based on 100 parts by
weight of the total resin solid content. When the amount of the organic phosphoric ester is smaller than 3 parts by weight, the effect of improving flame retardancy is small and the improvement of luster and flexibility is small and when the amount is larger than 30 parts by weight, the improvement of flame retardancy is small and the final product becomes sticky disadvantageously.
The organic phosphoric ester is preferably a phosphoric ester containing no halogen and having an elemental

phosphorus content of 7 to 18 wt% and a viscosity (20" C) of
10 to 150 cp. The organic phosphoric ester used in the
present invention is preferably allyl phosphate-based because
it has a flame retarding effect, compatibility with a resin
and a platioialng effect. pi 0.5 tic; z.ii^
[0010]
When an ammonium polyphosphate compound is used as a flame retardant in the present invention, the ammonium polyphosphate compound thermally decomposes at the time of combustion and generates nitrogen gas which shut off oxygen. The ammonium polyphosphate compound promotes the carbonization of a polyolefin as a dehydration carbonization catalyst while it generates nitrogen-containing gas, thereby improving a flame retarding effect. When a polyolefin and a polyurethane are used in combination, the blending ratios of these to the ammonium polyphosphate and the organic phosphoric ester are based on 100 parts by weight of the total resin solid content.
[0011]
When a metal hydroxide is further blended, a larger flame retarding effect is obtained advantageously. Preferred examples of the metal hydroxide include magnesium hydroxide, aluminum hydroxide, red phosphorus and ammonium polyphosphate from the viewpoint of a multiplication effect. When a metal hydroxide is blended, the obtained product becomes hard but the phosphoric ester softens the product, thus preventing it from becoming hard advantageously. The metal hydroxide must

be existent in an amount of 60 to 150 parts by weight based on 100 parts by weight of the total resin solid content of the polyolefin and the polyurethane,
When the amount of the metal hydroxide is smaller than-60 parts by weight based on 100 parts by weight of the total resin solid content, its effect of promoting flame retardancy is small. When the amount is larger than 150 parts by weight, the viscosity of the aqueous dispersion of the ethylene-vinyl acetate copolymer rises disadvantageously.
[0012]
As the aluminum hydroxide, for example, Hijilite H-42M and Hijilite H-43M (of Showa Denko K.K.) are used.
As the magnesium hydroxide, for example, Kismer 5A (of Kyowa Kagaku Kogyo Co., Ltd.) is used.
[0013]
A description is subsequently given of a flameproof mesh sheet comprising the flame retardancy of the present invention.
The multi-filament fiber used in the present invention is one or more multi-filament fibers selected from polyester, nylon, polypropylene, polyethylene and vinylon fibers. A polyester fiber is preferred from the viewpoints of strength and heat shrinkage.
The tensile strength of the multi-filament fiber is adjusted to 4 to 10 g/denier to increase the strength and reduce the weight of a flameproof mesh sheet, and the breaking extension thereof is adjusted to 14 to 45 % to

increase the toughness of a flameproof mesh sheet and improve the drop impact energy absorption thereof.
The multi-filament fiber has an equivalent single fineness of 3 to 17 denier, preferably 3 to 12 denier, particularly preferably 4 to 9 denier and a total fineness of 500 to 4,500 denier, preferably 1,000 to 3,500 denier, particularly preferably 1,500 to 3,000 denier.
[0014]
The multi-filament fiber used in cloth treated with a flame retardant after weaving has an equivalent single fineness of 2 to 13 denier, preferably 2 to 11 denier, particularly preferably 2.5 to 9 denier and a total fineness of 150 to 2,500 denier, preferably 200 to 2,000, particularly preferably 250 to 1,500 denier. The tensile strength of the multi-filament fiber is controlled to 4 to 10 g/denier to increase the strength and reduce the weight of a flameproof mesh sheet, and the breaking extension thereof is controlled to 14 to 45 % to increase the toughness of a flameproof mesh sheet and improve the drop impact energy absorption thereof.
A flameproof mesh sheet which must have high strength and high toughness is prepared by paralleling 2 to 4 multi¬filament fibers and leno weaving or imitation gauging the fibers with a loom. In the case of a scattering prevention flameproof mesh sheet, cloth is often made by plain weaving a single multi-filament fiber with a loom. In the case of a flameproof mesh sheet for houses having a small number of stories, cloth is often made by plain weaving or leno weaving

2 to 4 multi-filament fibers. The mesh length is preferably 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm.
[0015]
As for the weight ratio of the solid content of the flame retardant to the multi-filament fiber and cloth, the solid content of the flame retardant is 60 to 500 parts by weight based on 100 parts by weight of the multi-filament fiber and cloth. When the solid content of the flame retardant is smaller than 60 parts by weight based on 100 parts by weight of the multi-filament fiber or cloth, coating nonuniformity occurs and part of the texture of the rtiulti-filament fiber and cloth is exposed, thereby deteriorating appearance and reducing weatherability. Flameproofness also deteriorates» When the solid content is larger than 500 parts by weight, the obtained flameproof mesh sheet becomes heavy, thereby deteriorating handling properties disadvantageously,
[0016]
In the present invention, the types and amounts of a pigment, dye, plasticizer, ultraviolet absorber, optical stabilizer, antioxidant, stabilizer, coupling agent, defearning agent, dispersant, diluent, thickener, foaming agent, mildewproofing agent and the^TI)ce~~aH"'Tujrta^ selected and used in conjunction with the flame retardant,
A description is subsequently given of a process for producing the flameproof mesh sheet of the present invention. When the flameproof mesh sheet of the present invention is

produced using multi-filament fibers, the fibers are coated with a flame retardant through a sizing nozzle, and the leated and gelled coated yarn is taken up by a winder. The ::oated yarn taken up by the winder is woven by a loom. The ibtnlnnd fnbrlo In int.ro(lu(^.od .lnt.o a hnntlng furnaco nnd
leated to carry out i-'to obtain gray cloth. ^^^ f^x;^ u^sk
The gray cloth is cut to a predetermined size, sewed ind subjected to ^;^ ev^jeCS Processing to obtain a halogen-:ree flameproof mesh sheet. [0017]
When the flameproof mesh sheet of the present invention Ls produced using cloth, multi-filament fibers are woven with 1 dobby loom to obtain gray cloth. After the gray cloth is Immersed in a tank filled with a flame retardant for mesh ;heets and passed through the tank, it is dried with an air )low and introduced into a heating furnace to carry out heat [elation to obtain coated gray cloth. To increase the amount >f the flame retardant coated on the cloth, the cloth is mmersed in and passed through the tank filled with the flame etardant at least two times to produce coated gray cloth, he cloth is cut to a predetermined size, sewed and subjected
-f; X e/€. leti>
o non 9hlftin-g processing to obtain a halogen-free
lameproof mesh sheet.
[0018]
[Examples]
The following examples are given to further illustrate he present invention.

Excunple 1
200 parts by weight of the S-753 ethylene-vinyl acetate copolymer aqueous dispersion(of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) was charged into a planetary mixer (volume of 25 liters), and then 80 parts by weight of the Fostaphram AP-462 ammonium polyphosphate (of Hoechst Co., Ltd.), 120 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.), 0.8 part by weight of the Tinubin 327 ultraviolet absorber (of Ciba Geigy Co., Ltd.), 0.8 part by weight of the Irganox 1010 antioxidant (of Ciba Geigy Co., Ltd.), 1.0 part by weight of the HALS optical stabilizer (of Ciba Geigy Co., Ltd.), 2 parts by weight of the TIPAQUE C-97 titanium oxide (of Ishihara Sangyo Co., Ltd.) and 30 parts by weight of water were added little by little to the mixer under agitation over about 5 minutes. Agitation was further continued for 20 minutes. The pressure was gradually reduced to 5 mmHg and vacuum defoaming was carried out for about 30 minutes to give a flame retardant for mesh sheets having a viscosity of 3,530 cp (BM type viscometer, rotor V-6, 12 rpm, 25°C). The flame retardant was placed in a bath, polyester multi-filament fibers having a total fineness of 1,750 denier, each consisting of 384 filaments with an equivalent single fineness of 4.5 denier, a tensile strength of 8.5 g/denier and a breaking extension of 21 %, were passed through a guide, pinched with a pinch roll, passed through a guide roll, the bath of the flame retardant and a sizing nozzle (of 0.7 mm in diameter) to coat the

multi-filament fibers, and the obtained strand was heated at 170'C in a heating furnace and passed through a another sizing nozzle (of 0.8 mm in diameter) to coat the strand, and then heated at 190'C in a heating furnace to produce coated yarn of 3,980 denier. The weight ratio of the flame retardant for mesh sheets to the multi-filament fibers of the coated yarn was 130/100.
Plain weave cloth having a mesh length of 52 warps/10 cm and 52 wefts/10 cm was woven of the coated yarn with a rapier loom at a speed of 50 cm/min. Thereafter, this cloth was heated at 170'C by passing through a heating furnace to thermally fuse intersections between warps and wefts to obtain the flameproof mesh sheet of the present invention. The gray cloth was cut to a width of 190 cm and a length of
520 cm, sewed with a sewing machine and subjected to non-
e/e,lets "
shifting processing to obtain a 180 cm wide, 510 cm long
flameproof mesh sheet.
The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of a flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0019] Example 2
182 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd.) was used in place of the S-753 ethylene-vinyl acetate copolymer. The TIPAQUE C-97 titanium oxide was not

added. A flame retardant having a viscosity of 2,640 cp was obtained in the same manner as in Example 1 except above.
Multi-filament fibers having a total fineness of 3,000 denier, each consisting of 384 filaments with an equivalent single fineness of 7.8 denier, were passed through a sizing nozzle of 0.8 mm in diameter, gelled by heating, passed through a sizing nozzle of 0.9 mm in diameter and gelled by heating to obtain coated yarn of 5,815 denier,
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the coated yarn was processed into 30 warps/10 cm and 30 wefts/10 cm.
The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of a flameproof mesh sheet treated with the flame retardant are show in Table 3.
[0020] Example 3
182 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) was used in place of the S-753 ethylene-vinyl acetate copolymer. 55 parts by weight of; the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation), 15 parts by weight of the TCP organic phosphoric ester and 140 parts by weight of the Kismer 5A magnesium hydroxide (of Kyowa Kagaku Co., Ltd.) were used. Further, 8 parts by weight of the TIPAQUE C-97 titanium oxide was added. A flame retardant having a viscosity of 2,980 cp

was obtained in the same manner as in Example 1 except above.
Coated yarn of 8,852 denier was obtained using this flame retardant, the same multi-filament fibers as in Example 1, a sizing nozzle of 0.8 mm in diameter for the first coating and a sizing nozzle of 1.0 mm in diameter for the second coating.
A flameproof mesh sheet was obtained in the same manner as in Example 1 except above.
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that this flame retardant was used. The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0021] Example 4
80 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 55 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%), and 55 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) were used. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above.
The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the

flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0022] Example 5
55 parts by weight of the S-500 (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) and 60 parts by weight of the S-752 (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) in place of the S753 ethylene-vinyl acetate copolymer, 105 parts by weight of the Adecabontiter HUX-380 polyurethane (of Asahi Denka Kogyo Co., Ltd.,; the ;nain structure of a polyester, a solid content of 38 wt%), 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation), 5 parts by weight of the TOP organic phosphoric ester (of Daihachi Kagaku Co., Ltd.), and 100 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.) were used. Water was not further added. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above.
Multi-filament fibers of 1,500 denier were coated only once using a sizing nozzle of 0,7 mm in diameter. Coated yarn of 3,327 denier was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the coated yarn was processed into 25 warps/10 cm and 25 wefts/10 cm.
The composition of the flame retardant is shown in Table 1 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are

shown in Table 3.
[0023] Example 6
145 parts by weight of the S-951 ethylene-vinyl acetate-vinyl versatate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 53 parts by weight of the Adecabontiter HUX-380 polyurethane (of Asahi Denka Kogyo Co./ Ltd., the main structure of a polyester, a solid content of 38 wt%), 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation) and 120 parts by weight of the Hijilite H-42M aluminum hydroxide (of Showa Denko K.K.) were added. Water was not further added. A flame retardant for mesh sheets having a viscosity of 2,820 cp was obtained in the same manner as in Example 1 except above. A flame retardant for mesh sheets was obtained in the same manner as in Example 1 except that the flame retardant was used. The composition of the flame retardant is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 4.
[0024] Example 7
91 parts by weight of the S-910 ethylene-vinyl acetate-acrylic ester copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene-

vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%), 132 parts by weight of the Letan WB polyurethane (of Kansai Paint Co., Ltd., the main structure of a polyester, a solid content of 38 wt%) and 60 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corporation) were used. Water was not further add^d. A flame retardant for mesh sheets having a viscosity of 1,950 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 4.
[0025] Example 8
91 parts by weight of the S-500 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) and 100 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) were used in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%). Water was not further added. A flame retardant for mesh sheets having a viscosity of 1,820 cp was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2.
Imitation gauze cloth having a mesh length of 45

warps/10 cm and 45 wefts/10 cm was woven with a dobby loom using the flame retardant for mesh sheets and without using the coated multi-filament fibers in Example 1 by paralleling 3 multi-filament fibers of 750 denier to coat the cloth. The weight of the cloth was 225 g/m^.
The cloth was passed through a guide roll and a roll coater filled with the flame retardant, squeezed with a squeezing roll, dried with an air blow to remove the flame retardant filling the meshes of the cloth, and gelled in a heating furnace at 130"C, 160"C and 180'C. The coated gray cloth was taken up by a winder. The weight of the coated gray cloth was 482 g/m^ (mesh sheet gray cloth). The gray cloth was cut to a predetermined size, sewed and subjected to non ohifting processing to obtain a flameproof mesh sheet. The performance of the mesh sheet is shown in Table 4.
[0026] Example 9
Plain weave cloth having a mesh length of 120 warps/10 cm and 120 wefts/10 cm was woven of multi-filament fibers of 250 denier with a loom without coating the multi-filament fibers as in Example 8. The weight of the cloth was 66 g/m^.
The cloth was coated with the same flame retardant for mesh sheets as in Example 8 in the same manner as in Example 8 and yelled by heating, and the coated gray cloth having a weight of 134 g/m^ was taken up by a winder.
The gray cloth was cut to a predetermined size, sewed
and subjected to non-shifting processing to obtain a 1/

flameproof mesh sheet for houses having a small number of
stories .
The composition of the flame retardant used is shown in Table 2 and the measurement results of the performance of the flameproof mesh sheet for houses having a small number of stories treated with the flame retardant are shown in Table 4
[0027]
Example 10
145 parts by weight of the S-500 ethylene-vinyl acetate
copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 55 wt%) in place of the S-753 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., a solid content of 50 wt%) and 53 parts by weight of the Letan WB polyurethane (of Kansai Paint Co., Ltd., a solid content of 38 wt%) were used. A flame retardant for mesh sheets having a viscosity of 1,960 cp was obtained in the same manner as in Example 1 except above. The composition of the flame retardant is shown in Table 2.
The same cloth as in Example 9 was coated with the flame retardant for mesh sheets in the same manner as in Example 9, and the obtained coated gray cloth having a weight of 155 g/m^ was taken up by a winder.
The gray cloth was cut to a predetermined size, sewed
and subjected to non ghifting processing to obtain a
flameproof mesh sheet for houses having a small number of stories.
The measurement results of the performance of the

flameproof mesh sheet for houses having a small number of stories are shown in Table 4.
[0028] Comparative Example 1
The amount of the AP-462 Fostaphram ammonium polyphosphate (of Client Japan Co., Ltd.) used in Example 1 was changed to 30 parts by weight. A flame retardant having a viscosity of 2,310 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 1.
The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.
[0029] Comparative Example 2
The amount of the AP-462 Fostaphram ammonium polyphosphate (of Client Japan Co., Ltd.) used in Example 1 was changed to 150 parts by weight. A flame retardant having a viscosity of 2,880 cp was obtained in the same manner as in Example 1 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 1.
The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the
flameproof mesh sheet treated with the flame retardant are shown in Table 7. [0030]

Comparative Example 3
The amount of the Kismer-5 magnesium hydroxide (of Kyowa Kagaku Kogyo Co., Ltd.) used in Example 3 was changed to 50 parts by weight. A flame retardant having a viscosity of 2,360 cp was obtained in the same manner as in Example 3 except above. A flameproof mesh sheet was produced using the flcime retardant in the same manner as in Example 3.
The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.
[0031] * Comparative Example 4
The amount of the Hijilite H-42H aluminum hydroxide (of Showa Denko K.K.) used in Example 6 was changed to 170 parts iby weight. A flame retardant having a viscosity of 3,270 cp was obtained in the same manner as in Example 6 except above. A flameproof mesh sheet was produced using the flame retardant in the same manner as in Example 6.
The composition of the flame retardant is shown in Table 5 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.
[0032] Comparative Example 5
A sizing nozzle of 0.6 mm in diameter was used in place of the sizing nozzle of 0.7 mm in diameter used in Example 1

A flameproof mesh sheet having a weight of 346 g/m^ was produced by coating and heating in the same manner as in Example 8 except that the flame retardant aqueous dispersion was used and the same cloth as in Example 8 was used.
The composition of the flame retardant is shown in Table 6 and the measurement results of the performance of the flameproof mesh sheet treated with the flame retardant are shown in Table 8.

(Notes)
® expressed in parts by weight based on 100 parts by weight
of the resin solid content.
The unit of values of the coated cloths of Examples 8, 9
and 10 is g/im^.
The finenesses and numbers of filaments of multi-filament
fibers for the cloths of Examples 8, 9 and 10 are 750
denier x 3, 250 denier x 1, and 250 denier x 1,
respectively. (§) The combustion test of Examples 5, 7, 9 and 10 is based
on A-1 method in which heating is carried out for 1
minute and fire is caught after 3 seconds.
A is TERRAJU-60 (of Chisso Corporation). (D B is Fostaphram AP462 (of Client Japan Co., Ltd.).
(7) C is Hijilite H-42M (of Showa Denko K.K.).
(8) D is Kismer 5A (of Kyowa Kagaku Co., Ltd.).
® The columns of the fineness (De) of the coated yarn and the coated cloth are for coated cloth in Examples 8, 9 and 10 and coated yarn in other examples. [0044]
Methods for measuring properties
1. viscosity measurement method
DM type viscometer, rotor No. 6, revolution of 12 rpm. 25* C
2. combustion test
based on JIS L-1091

A-1 method (45'C, micro-burner method)
A-2 method (45*" C, meckel burner method)
D method (number of times of flame contact)
3. tensile strength test measured based on JIS L-1068
4. analysis of combustion gas
(1) combustion gas generation method
tubular electric furnace method: based on JIS K 2541 combustion temperature: SSOilC* C amount of sample: 0.3 g air flow rate: 1,000 ml/min
(2) detection method
hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen fluoride (HF): detected by ion chromatography after treated based on JIS K 0107
5. drop impact strength (penetration test)
measured based on JIS-8952.
A steel tube having an outer diameter of 48,6 nun, a thickness of 2.5 mm and a weight of 2,7 kg was used in this test in the case of a flameproof mesh sheet for houses having a small number of stories and scattering prevention flameproof mesh sheet,
6. flexibility
excellent (soft) @
good O
slightly good D
slightly bad (hard) A

bad X
sticky X X
7 . color difference
(1) manufacturer: DATA COLOR INTERNATIONAL LTE
(2) type: SPECTRA FLASH SF-600
(3) measurement method: DE (whiteness) and DL (brightness) of a sample piece are measured using a white substrate as a reference.
(4) preparation of sample piece: After a flame retardant for mesh sheets is poured into a 10 cm wide, 15 cm long and 1 mm deep SUS frame, the flame retardant for mesh sheets above the top of the SUS frame is removed by a SUS bar, the other flame retardant is heated in a heating furnace at 150** C for 5 minutes, and then the sample piece is taken out to prepare a sample piece.
[0045] (Effect of the Invention]
The flameproof mesh sheet of the present invention is excellent in flame retardancy and satisfactory in terms of drop impact strength without generating harmful halogen gas at the time of combustion.

[Type of the Document] Specification
[Title of the Invention] FLAME RETARDANT FOR MESH SHEETS AND
FLAMEPROOF MESH SHEET COMPRISING THE SAME

[Claim 1] A flame retardant for mesh sheets which comprises 40 to 130 parts by weight of an ammonium polyphosphate compound and 60 to 150 parts by weight of a metal hydroxide based on 100 parts by weight of the solid content of a polyolefin resin aqueous dispersion having a resin solid content of 25 to 75 wt%.
[Claim 2] The flame retardant for mesh sheets according to claim 1, wherein the polyolefin resin aqueous dispersion is at least one selected from an aqueous dispersion of an ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of ethylene, having a resin solid content of 25 to 75 wt%, an aqueous dispersion of an ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, and an aqueous dispersion of an ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%.
[Claim 3] The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate copolymer of 10 to 95 wt% of vinyl acetate and the balance consisting of

ethylene, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 part by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content
[Claim 4] The flame retardant for mesh sheets according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-vinyl versatate copolymer of 5 to 30 wt% of ethylene, 15 to 70 wt% of vinyl acetate and 25 to 75 wt% of vinyl versatate, having a resin solid content of 30 to 70 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by weight of the total resin solid content.
[Claim 5] The flame retardant for mesh sheet according to claim 1 or 2 which is prepared by blending the aqueous dispersion of the ethylene-vinyl acetate-acrylic ester copolymer of 5 to 30 wt% of ethylene, 10 to 75 wt% of vinyl acetate and 20 to 85 wt% of acrylic ester, having a resin solid content of 25 to 75 wt%, with a polyurethane aqueous dispersion having a solid content of 25 to 70 wt% in a solid content ratio of 90/10 to 30/70 and adding 40 to 130 parts by weight of the ammonium polyphosphate compound and 60 to 150 parts by weight of the metal hydroxide based on 100 parts by

weight of the total resin solid content.
[Claim 6] The flame retardant for mesh sheets according to any one of claims 1 to 5, wherein the ammonium polyphosphate compound is microcapsulated.
[Claim 7] The flame retardant for mesh sheets according to any one of claims 1 to 6, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide.
[Claim 8] A flame retardant for mesh sheets which is prepared by blending 3 to 30 parts by weight of an organic phosphoric ester with the flame retardant for mesh sheets according to any one of claims 1 to 7 based on 100 parts by weight of the solid content of the aqueous dispersion resin of the flame retardant.
[Claim 9] The flame retardant for mesh sheets according to claim 8, wherein the organic phosphoric ester is a halogen-free phosphoric ester.
[Claim 10] A flameproof mesh sheet woven of coated yarn
prepared by coating multi-filament fibers with the flame
retardant for mesh sheets of any one of clams 1 to 9 through impregnation and heating.
[Claim 11] The flameproof mesh sheet according to claim 10, wherein the multi-filament fibers have an equivalent single fineness of 3 to 17 denier, a total fineness of 500 to 4,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %.
[Claim 12] A flameproof mesh sheet prepared by coating mesh sheet cloth woven of multi-filament fibers with the

flame retardant for mesh sheets of any one of claims 1 to 9 through impregnation and heating.
[Claim 13] The flameproof mesh sheet according to claim 12, wherein the mesh sheet cloth woven of multi-filament fibers is prepared by plain weaving synthetic fibers having an equivalent single fineness of 2 to 13 denier, a total fineness of 150 to 2,500 denier, a tensile strength of 4 to 10 g/denier and a breaking extension of 14 to 45 %, or by paralleling 2 to 4 fibers and leno weaving or imitation gauging theni with a loom, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm.
[Claim 14] Flameproof mesh sheet cloth woven of multi¬filament fibers coated with 60 to 500 parts by weight of the flame retardant for mesh sheets according to any one of claims 1 to 8 through impregnation based on 100 parts by weight of the mesh sheet cloth woven of multi-filament fibers or multi-filaments.

lb. A flsme retardant for mesh sheets/ substantially as hereinabove described and exemplified.

Documents:

567-mas-1999-abstract.pdf

567-mas-1999-claims filed.pdf

567-mas-1999-claims granted.pdf

567-mas-1999-correspondnece-others.pdf

567-mas-1999-correspondnece-po.pdf

567-mas-1999-description(complete) filed.pdf

567-mas-1999-description(complete) granted.pdf

567-mas-1999-form 1.pdf

567-mas-1999-form 26.pdf

567-mas-1999-form 3.pdf

567-mas-1999-form 5.pdf

567-mas-1999-other documents.pdf

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Patent Number

213938

Indian Patent Application Number

567/MAS/1999

PG Journal Number

13/2008

Publication Date

31-Mar-2008

Grant Date

23-Jan-2008

Date of Filing

18-May-1999

Name of Patentee

KYOWA KABUSHIKI KAISHA

Applicant Address

1-13-20, MINAMISENBA, CHUO-KU, OSAKA-SHI, OSAKA-FU,

Inventors:

#	Inventor's Name	Inventor's Address
1	KUNIAKI KAMIYA	1-13-20, MINAMISENBA, CHUO-KU, OSAKA-SHI, OSAKA-FU,
2	SAIJI NOZAKI	2063, AIMOTOSHIN, UNAZUKI-MACHI, SHIMONIIKAWA-GUN, TOYAMA-KEN,

PCT International Classification Number

D06 M 13/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	199406/1998	1998-06-11	Japan
2	130 420/99	1999-04-02	Japan