Title of Invention

FLAME RETARDANT FOR MESH SHEETS AND FLAMEPROOF MESH SHEET COMPRISING THE SAME

Abstract A flame retardant for mesh sheets comprising red phosphorus in an amount of 1.5 to 15 parts bu weight , an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight based on 100 parts by weight of the solid content of an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt%.
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 a construction site for a long time.
[0002]
[Prior Art]
In recent years, there has been a trend toward the construction of buildings having a large number of stories in the construction industry. Meanwhile, there has been an Increase in the number of houses having a small number of stories. Flameproof mesh sheets for safety and protection, flameproof mesh sheets for houses having a small number of stories and scattering prevention flameproof mesh sheets must be laid in these buildings and regulations are becoming more and more strict.
Currently used flameproof mesh sheets and scattering prevention flameproof mesh sheets are produced by weaving yarn prepared by coating a polyester, nylon or polypropylene multi-filament fiber with a vinyl chloride-based paste resin composition and heating and then heating the obtained cloth and by coating a fabric prepared by weaving and processing a multi-filament fiber with a vinyl chloride-based paste resin

composition, heating and processing to a desired shape,
respectively.
The resin composition for coating a fiber and fabric comprises a vinyl chloride resin containing chlorine as a resin and a chlorine-based flame retardant such as chlorinated paraffin, bromine-based flam© retardant such as decabromodiphenyl oxide or inorganic flame retardant such as antimony trioxide {Examined Japanese Patent Publication Nos. 52-41786, 53-18065 and 61-94305, 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 the environmental preservation of the earth.
Japanese Laid-open Patent Application No. 61-223045 proposes that red phosphorus and ammonium polyphosphate are kneaded into a polyolefin to prevent corrosion by elemental halogen contained in an elemental halogen-containing
compound flame retardant. However, there is unknown a flame retardant prepared by dispersing red phosphorus and ammonium phosphate in an aqueous dispersion of an ethylene-vinyl acetate copolymer or an aqueous dispersion comprising the aqueous dispersion and an aqueous dispersion of an a-olefin copolymer and/or an aqueous dispersion of a polyurethane.
The inventor of the present invention has proposed in Japanese Laid-open Patent Application No. 9-225464 a halogen-free flame retardant comprising an aqueous dispersion of a polyolefin resin as a flame retardant. This flame retardant has an excellent effect but there is seen a

tendency toward an increase in the viscosity of the flame retardant due to time changes during storage.
The inventor of the present invention has also proposed in Japanese Laid-open Patent Application No. 9-312550 a halogen-free flame retardant comprising an aqueous dispersion of an ethylene-vinyl acetate copolymer containing 10 to 90 parts by weight of vinyl acetate. This flame retardant has an excellent effect and function and the present invention further improves the gloss, flexibility and flame retardancy of this invention. A flameproof mesh sheet having an extremely excellent gloss and flexibility is strongly desired in a field using mesh sheets.
[0003]
[Problem to Be Solved by the Invention]
In view of the above situation, it is an object of the present Invention to provide a flame retardant for halogen-free flameproof mesh sheets which does not experience a rise in viscosity during storage, has an excellent gloss and
flexibility and does not generate harmful halogen gas at the time of combustion, and a flameproof mesh sheet comprising the same.
[0004]
[Means for Solving the Invention]
The present invention relates to: 1 A flame retardant for mesh sheets comprising red phosphorus in an amount of 1,5 to 15 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the

solid content of an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt%.
2, A flame retardant for mesh sheets prepared by mixing an
aqueous dispersion of an a-olefin copolymer having a solid
content Of 20 to 45 wt% with an aqueous dispersion of an
ethylene-vinyl acetate copolymer having a vinyl acetate
content of 10 to 95 wt% and a resin solid content of 25 to
75 wt% in a solid content weight ratio of 10:90 to 70:30 and
adding red phosphorus in an amount of 1.5 to 15 parts by
weight, an ammonium polyphosphate compound in an amount of
10 to 50 parts by weight and an organic phosphate in an
amount of 3 to 30 parts by weight based on 100 parts by
I
weight of the total resin solid content.
3, A flame retardant for mesh sheets prepared by mixing an
aqueous dispersion of a polyurethane having a solid content
of 25 to 70 wt% with an aqueous dispersion of an ethylene-
vinyl acetate copolymer having a vinyl acetate content of 10
to 95 wt% and a resin solid content of 25 to 75 wt% in a
solid content weight ratio of 10:90 to 90:10 and adding red
phosphorus in an amount of 1.5 to 15 parts by weight, an
ammonium polyphosphate compound in an amount of 10 to 50
parts by weight and an organic phosphate in an amount of 3
to 30 parts by weight based on 100 parts by weight of the
ii'
total resin solid content.
4, A flame retardant for mesh sheets prepared by mixing an
aqueous dispersion of an a-olefin copolymer having a solid
content of 20 to 45 wt% and an aqueous dispersion of a
polyurethane having a solid content of 25 to 70 wt% with an

aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt% in a solid content weight ratio of 10:10:80 to 50:80:10 and adding red phosphorus in an amount of 1.5 to 5 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the total resin solid content.
5. The flame retardant for mesh sheets of any one of claims 1 to 4, wherein red phosphorus is micro-capsulated.
6. The flame retardant for mesh sheets of any one of claims 1 to 5, wherein the ammonium polyphosphate compound is micro-capsulated.
7. The flame retardant for mesh sheets of any one of claims 1 to 6, wherein the organic phosphate is an organic phosphate containing no elemental halogen.
8. A flame retardant for mesh sheets prepared by mixing a metal hydroxide in an amount of 30 to 150 parts by weight based on 100 parts by weight of the solid content of the aqueous dispersion resin of the flame retardant for mesh sheets of any one of claims 1 to 7 with the flame retardant.
9. The flame retardant for mesh sheets of claim 8, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide.
10. A flameproof mesh sheet woven out of coated yarn which is impregnated with the flame retardant for mesh sheets of any one of claims 1 to 9 and heated.

11. The flcuneproof mesh sheet of claim 10, wherein the coated yarn is a multi-filament fiber having an equivalent single fineness of 3 to 17 denier, a total fineness of 500 to 4,500 denier, a tensile strength of 4 to l0 g/denier and an elongation at break of 14 to 45 %.
12. A flameproof mesh sheet prepared by impregnating a mesh sheet fabric woven out of multi-filament fibers with the flame retardant for mesh sheets of any one of claims 1 to 9 and heating.
13. The flameproof mesh sheet of claim 12, wherein the mesh sheet fabric woven out of multi-filament fibers is a mesh sheet fabric prepared by paralleling 1 to 4 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 an elongation at break of 14 to 45 % and leno weaving them with a weaving machine, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm.
14. The flcimeproof mesh sheet of any one of claims 10 to 13, wherein the amount of the flame retardant for mesh sheets of any one of claims 1 to 9 used to impregnate multi-filament fibers or a mesh sheet fabric woven out of the multi¬filament fibers is 60 to 350 parts by weight based on 100 parts by weight of the multi-filament fibers or the mesh sheet fabric.
[0005]
[Embodiments of the Invention]
An aqueous dispersion of an ethylene-vinyl acetate copolymer is used as a base material in the present invention because a multi-filament fiber and fabric are

fully impregnated with a flame retardant and uniformly coated with the flame retardant. The aqueous dispersion makes impregnation and coating easy.
The ethylene-vinyl acetate copolymer used in the present invention advantageously comprises 10 to 95 wt% of vinyl acetate and the aqueous dispersion of the ethylene-vinyl acetate copolymer preferably has a solid content of 27 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.), S-301, S-500, S-706, S-751 and S-752 (of Sumitomo Chemical Company,
Ltd.).
Since the ethylene-vinyl acetate copolymer has a group represented by -OCO-CH3 and a large amount of oxygen, its
flame retarding effect is large when it is used in combination with red phosphorus and ammonium polyphosphate.
[0006]
In the present invention, an a-olefin copolymer can be used in combination with this aqueous dispersion of the ethylene-vinyl acetate copolymer, and a dispersion of the a-olefin copolymer preferably has a solid content of 20 to 45 wt%, a particle diameter of 1 to 10 jam, a pH of 8 to 11, a viscosity of 2,000 to 8,000 cp (a BM type viscometer, 6 rotations) and a resin surface hardness of A-80 to 97 (Shore A: ASTMD). The a-olefin copolymer is preferably a thermoplastic elastomer resin containing ethylene in an amount of 50 wt% or more, such as A-lOO or A-200 (Mitsui Petrochemical Industries, Ltd.).

The aqueous dispersion of the ethylene-vinyl acetate copolymer is excellent in flame retarding effect and keeping quality with a small rise in viscosity due to time changes but the feeling of a mesh sheet treated with this dispersion is slightly hard.
When an aqueous dispersion of an a-olefin copolymer is used in combination with the above dispersion to improve this, the feeling of the mesh sheet becomes soft. The amount of the a-olefin copolymer is 10 to 70 wt% based on 90 to 30 wt% of the solid content of the ethylene-vinyl acetate copolymer. When the amount is smaller than 10 wt%, the improvement of the feeling is small and when the amount is larger than 70 wt%, flameproofness deteriorates disadvantageously.
When the polyurethane aqueous dispersion is further used together to improve the feeling, the feeling becomes soft and the gloss becomes satisfactory most advantageously.
[0007]
The amount of the polyurethane is 10 to 90 wt% based on 90 to 10 wt% of the solid content of the ethylene-vinyl acetate copolymer. When the amount is smaller than 10 wt%, the Improvements of feeling and gloss are small and when the amount is larger than 90 wt%, flameproofness deteriorates disadvantageously. A polyurethane having the main structure of a polyester, polyol or polycarbonate is used as the polyurethane. Out of these, a polyurethane having the main structure of a polyester is preferred from the viewpoint 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., Adecaljontiter HUX-380, Adecabontiter HUX-232, Adecabontiter HUX-290H, Adecabontiter HUX-350 and Adecabontiter HUX-386H of Asahi Denka Kogyo Co., Letan WB of Kansai Paint Co., and the like.
[0008]
The present invention contains a fleime retardant comprising an aqueous dispersion of an ethylene-vinyl acetate copolymer, an aqueous dispersion of an a-olefin copolymer and an aqueous dispersion of a polyurethane.
As for the amounts of the a-olefin copolymer and the polyurethane, the a-olefin copolymer is used in an amount of 10 to 50 wt% and the polyurethane is used in an amount of 10 to 70 wt% based on 80 to 10 wt% of the solid content of the ethylene-vinyl acetate copolymer. When the amount of the a-olefin copolymer is smaller than 10 wt%, the improvement of feeling is small and when the amount is larger than 50 wt% and the a-olefin copolymer is used in combination with the polyurethane, flameproofness deteriorates disadvantageously. When the amount of the polyurethane is smaller than 10 wt%, the improvements of feeling and gloss are small and when the amount is larger than 70 wt% and the polyurethane is used in combination with the a-olefin copolymer, flameproofness deteriorates disadvantageously.

The flame retardant of the present invention contains red phosphorus In an amount of 1.5 to 15 parts by weight based on 100 parts by weight of the total resin solid content. When the amount of red phosphorus Is smaller than 1.5 parts by weight. Its flame retarding effect Is small and when the amount Is larger than 15 parts by weight, the product has a strong red tint dlsadvantageously.
Red phosphorus used In the present invention is preferable mlcro-oapsulated. Use of the micro-encapsulated red phosphorus makes it possible to reduce an Increase in the viscosity of an aqueous dispersion when red phosphorus is mixed into the olefin aqueous dispersion. Further, the flameproof mesh sheet is detached and washed to remove dirt after it is spread 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. At this point, red phosphorus can be prevented from dissolving in water by micro-encapsulation. The concentration of red phosphorus is 75 to 95 % and the average particle diameter thereof is 10 to 40 \xm.
Micro-encapsulation can be suitably carried out by coating the surface of a red phosphorus particle with a resin or inorganic material by Interfaclal polymerization, coacervatlon or the like.
[0010]
The ammonium polyphosphate compound used In the present invention Is ammonium polyphosphate or amide polyphosphate. Use of the micro-encapsulated ammonium polyphosphate compound makes it possible to reduce an Increase in the

viscosity of the aqueous dispersion when the ammonium
polyphosphate compound is mixed into the aqueous dispersion
of an olefin resin. Further, the flameproof mesh sheet is
detached and washed to remove dirt after it is spread 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 f
containing a detergent. At this point, the ammonium polyphosphate compound can be made hardly soluble in water and stable by micro-encapsulation. The concentration of phosphorus contained in the ammonium polyphosphate compound is 15 to 35 % and the average particle diameter thereof is 5 to 40 pni- Micro-encapsulation can be carried out in the same manner as red phosphorus.
The flame retardant of the present invention contains an mnmonium polyphosphate compound in an amount of 10 to 50 parts by weight based on 100 parts by weight of the total resin solid content. When the amount of the ammonium polyphosphate compound is smaller than 10 parts by weight, its flame retarding effect is small and when the amount is larger than 50 parts by weight, there is no further improvement of its flame retarding effect. Therefore, it is not necessary to add a large amount of the ammonium polyphosphate compound.
[0011]
The flame retardant of the present invention contains an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the total resin solid content- When the amount of the organic phosphate is smaller than 3 parts by weight, its flame retarding effect is small

and the improvements of gloss and flexibility are small and when the amount is larger than 30 parts by weight, the improvement of flame retardancy is small and the product becomes sticky disadvantageously.
The organic phosphate is a halogen-free organic phosphate having an elemental phosphorus content of 7 to 18 wt% and a viscosity {20'C) of 10 to 150 cp- The organic phosphate used in the present invention is preferably allyl phosphate because it has a flame retarding effect, high compatibility with resins and a plasticating effect.
[0012]
Red phosphorus and an ammonium polyphosphate compound are used as flame retardants in the present invention because when a resin composition containing red phosphorus is brought close to flames, the resin and red phosphorus on the surface first burn and the resin is bonded to oxygen in the air to become carbon dioxide gas, water and carbon. In this case, red phosphorus promotes the carbonization of the ethylene-vlnyl acetate copolymer and the a-olefin copolymer and/or polyurethane. Meanwhile, red phosphorus is bonded to oxygen to become an oxide which is further bonded to water to become condensation phosphoric acid. A film made from a mixture of carbon and condensation phosphoric acid formed on the surface of the resin becomes an oxygen impermeable layer ort the surface of the resin, suppresses the combustion of the resin and makes the resin flame resistant. Therefore, the ethylene-vinyl acetate copolymer containing a large amount of oxygen is effective in forming condensation red phosphoric acid. Red phosphorus must be existent in an

amount of 1.5 to 15 parts by weight based on 100 parts by weight of the solid content of the aqueous dispersion of the ethylene-vinyl acetate copolymer having a solid content of 20 to 75 wt%. When the content of red phosphorus is less than 1.5 parts by weight based on the resin solid content, its flame- retarding effect is not provided and when the content is more than 15 parts by weight, its flame retarding effect is not improved, and the resulting flameproof mesh sheet has a strong red tint and is difficult to be colored even with a pigment.
[0013]
In this case, when an ammonium polyphosphate compound is existent, it thermally decomposes at the time of combustion and generates nitrogen gas which shuts off oxygen. The ammonium polyphosphate compound promotes the carbonization of the ethylene-vinyl acetate copolymer as a dehydrocarbonizing agent and improves a flame retarding effect while it generates nitrogen-containing gas. In the present invention, the ammonium polyphosphate compound must be existent in an amount of 15 to 50 parts by weight based on 100 parts by weight of the solid content of an aqueous dispersion of an ethylene-vinyl acetate copolymer having a solid content of 20 to 75 %. Below 15 parts by weight, a flame retarding effect is not provided and above 50 parts by weight, a flame retarding effect is not improved when the ammonium polyphosphate compound is used in combination of an organic phosphate. When an a-olefin copolymer and a polyurethane are used in combination with the aqueous dispersion of the ethylene-vinyl acetate copolymer, the

above amounts of red phosphorus, ammonium polyphosphate and organic phosphate are based on 100 parts by weight of the total resin solid content.
[0014]
Nova Excel 140 or Nova Red 120 (Rin Kagaku Kogyo Co.) is used as red phosphorus.
TERRAJU-60 or TERRAJU-70 (Chisso Corp.), or Hostafuram AP462 (Hoechst Japan Co.) is used as the ammonium polyphosphate compound.
TCP, CDF or TOP (Daihachl Kagaku Co.) is used as the organic phosphate.
[0015]
vmen a metal hydroxide is further used, a great flame retarding effect is obtained advantageously. The metal hydroxide is preferably magnesium hydroxide or aluminum hydroxide which can be used in conjunction with red phosphorus and ammonium polyphosphate to obtain a greater effect. When the metal hydroxide is used, the product becomes hard but a phosphate makes the product soft advantageously. The metal hydroxide must be existent in an eunount of 30 to 150 parts by weight based on 100 parts by weight of the total resin solid content of the aqueous dispersion of the ethylene-vinyl acetate copolymer, the a-olefin resin and the polyurethane.
When the amount of the metal hydroxide is smaller than 30 parts by weight based on the. resin solid content, its effect of promoting flame retardancy is small and when the amount is larger than 150 parts by weight, the viscosity of

the aqueous dispersion of the ethylene-vinyl acetate copolymer Increases disadvantageously.
[0016]
As the aluminum hydroxide Is used Hljillte H-42M or Hijlllte H-43M (Showa Denko K.K.).
As the magnesium hydroxide Is used Kisuma 5 (Kyowa Kagaku Kogyo Co.)•
{0017]
A description Is subsequently g£ven of a flameproof mesh sheet comprising the flame retardant of the present invention.
The multi-filament used in the present invention is at least one multi-filament selected from polyesters, nylons, polypropylene and vinylon. It is preferably a polyester fiber from viewpoints of strength and thermal shrinkage.
A high-strength and lightweight flameproof mesh sheet can be obtained by controlling the tensile strength of the multi-filament fiber to 4 to 10 g/denier. A flameproof mesh sheet having high toughness and high impact energy absorption at the time of falling can be obtained by controlling the elongation at break of the multi-filament fiber to 14 to 45 %.
The multi-filament which is treated with a flame retardant and then woven has an equivalent single fineness o* 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.

The multi-filament used in a fabric which is woven and then treated with a flame retardant 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 denier, particularly preferably 250 to 1,500 denier. By controlling tensile strength to 4 to 10 g/denier, a high-strength and lightweight flameproof mesh sheet can be obtained and by controlling elongation at break to 14 to 45 %, a flameproof mesh sheet having high toughness and high impact energy absorption at the time of falling can be obtained.
A flameproof mesh sheet which needs to have high strength and toughness is prepared by paralleling 1 to 4 filament fibers and weaving an imitation gauze out of the fibers with a Dobby weaving machine. A scattering prevention flameproof mesh sheet is prepared by weaving an imitation gauze out of a single filament fiber with a weaving machine in most cases. A flameproof mesh sheet for houses having a small number of stores is prepared by leno weaving 1 to 4 filament fibers into a fabric.
[0019]
As for the solid content weight ratio of the flame retardant to the multi-filament fiber or fabric, the flame retardant is used in an amount of 60 to 250 parts by weight based on 100 parts by weight of the multi-filament fiber or fabric. When the solid content of the flame retardant is less than 60 parts by weight based on 100 parts by weight of the multi-filament fiber or fabric, coating becomes nonuniform and the multi-filament fiber or the base of the

fabric is partly exposed, thereby deteriorating outer appearance and weatherability. Further, flameproofness also lowers. When the solid content is more than 250 parts by weight, the weight of the flameproof mesh sheet increases with the result that handling properties deteriorate disadvantageously. [0020]
A pigment, dye, plasticizer, ultraviolet absorber, optical stabilizer, antioxidant, stabilizer, diluent, thickening agent, foaming agent, mold preventing agent, alga preventing agent and the like can be used in conjunction with the flame retardant in the present invention by suitably selecting types and amounts thereof.
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 a multi-filament fiber, coated yarn prepared
by coating the fiber with a flame retardant through a sizing
nozzle and gelling by heating is taken up by a winder. This
coated yarn taken up by the winder is woven into a fabric by
a weaving machine. This fabric is introduced into a heating
furnace and heated for non-shifting processing in order to
obtain gray cloth.
This cloth is cut to a predetermined size, sewed and subjected to non-shifting processing to obtain a halogen-free flameproof mesh sheet.
When the flameproof mesh sheet of the present invention is produced using a fabric, woven cloth is obtained by weaving the multi-filament fiber with a Dobby weaving

I
machine. After this woven cloth is immersed in a tank filled with a flame retardant for mesh sheets and let pass through the tank, it is dried with an air blow, introduced into a heating furnace and gelled by heating to obtain coated cloth. To Increase the amount of the flame retardant coated on the cloth, the cloth is immersed in and let pass through the tank filled with the flame retardant at least two times to produce coated cloth. The cloth is cut to a predetermined size, sewed and subjected to non-shifting processing to produce a halogen-free flameproof mesh sheet.
[0021]
[Examples] Example 1
250 parts by weight of the V-200 aqueous dispersion of an ethylene-vinyl acetate copolymer (of Mitsui Petrochemical Industries, Ltd., liaving a vinyl acetate content of 19 wt% and a solid content of 45 wt%) was injected into a planetary mixer (volume of 25 liters), and then 6 parts by weight of the Nova Excel 140 red phosphorus, 30 parts by weight of the TERRAJU-60 ammonium polyphosphate (of Chisso Corp.)* 10 parts by weight of the TCP phosphate (of Daihachi Kagaku Co.), 0.8 part by weight of the Tinuabin 327 ultraviolet absorber (of Chiba Geigy Co.), 0.8 part by weight of the Irganox 1010 antioxidant (of Chiba Geigy Co.), 1.0 part by weight of the HALS optical stabilizer (of Chiba Geigy Co.) and 1.0 part by weight of titanium oxide were added little by little over about 5 minutes under agitation. 10 parts by weight of isopropyl alcohol was then added. After addition, these materials were stirred for another 20 minutes. Then, .

vacuum defoaming was carried out at a reduced pressure of 5 mmHg for about 30 minutes to obtain a flame retardant for mesh sheets having a viscosity of 2,850 cp {a BM type viscometer, rotor V-6, 12 rpm, 25'C). The flame retardant was charged into a bath, and a polyester multi-filament fibery consisting of 384 filaments and having a total fineness of 1,750 denier, an equivalent single fineness of 4.5 denier, a tensile strength of 8.5 g/denier and an elongation at break of 21 % was caused to pass through a &ulde, pinched with a pinch roll, and further pass through a guide roll, the bath of the flame retardant and then a sizing nozzle (diameter of 0.7 mm) to be coated. Thereafter, the obtained strand was heated in a heating furnace at 150°C and caused to pass through another sizing nozzle (diameter of 0.8 mm) to coat the multi-filament fiber. The strand was further heated in a heating furnace at 180° C to produce coated yarn of 3,820 denier. The weight ratio of the flame retardant for mesh sheets to the multi-filament fiber was 118/100.
Thereafter, the coated yarn was woven into a mesh plain weave fabric of 52 warps/10 cm and 52 wefts/10 cm with a rapier loom at a speed of 50 cm/min. This fabric was then heated in a heating furnace at 160°C to thermally fuse ^intersecting points between the warps and wefts to obtain the flameproof mesh sheet of the present invention. Further, this cloth was cut to a width of 190 cm and a length of 520 cm, sewed with a sewing machine and subjected to non-shifting processing to obtain a flameproof mesh sheet having a width of 180 cm and a length of 510 cm.

The composition of the flame retardant is shown in Table 1 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0022] Example 2
A flame retardant having a viscosity of 1,530 cp was obtained in the same manner as in Example 1 except that 200 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., having a vinyl acetate content of 90 wt% and a solid content of 50 wt%) was used in place of the V-200 ethylene-vinyl acetate copolymer and isopropyl alcohol was not added.
A multi-filament fiber of 3,000 denier was used to obtain coated yarn of 5,676 denier by using a first sizing nozzle having a diameter of 0.8 mm and a second sizing nozzle having a diameter of 0.9 mm.
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the coated yarn was formed 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 properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0023] Example 3
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that 175 parts by weight of the V-200 ethylene-vinyl acetate copolymer (of Mitsui Petrochemical -

Industries, Ltd., having a vinyl acetate content of 19 wt% and a solid content of 40 wt%) and 175 parts by weight of the A-100 a-olefin copolymer (of Mitsui Petrochemical Industries, Ltd., having a solid content of 40 wt%) were used in place of the ethylene-vinyl acetate copolymer. The composition of the flame retardant is shown in Table 1 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0024] Example 4
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that 125 parts by weight of the V-200 ethylene-vinyl acetate copolymer (of Mitsui Petrochemical Industries Ltd., having a vinyl acetate content of 19 wt% and a solid content of 40 wt%) and 100 parts by weight of the Despacol U-42 polyurethane (of Sumitomo Viel Urethane Co., having the main structure of a polyester and a solid content of 50 wt%) were used and isopropyl alcohol was not added*
The composition of the flame retardant is shown in Table 1 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 3,
[0025] Example 5
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that 150 parts by weight of the V-200 ethylene-vinyl acetate copolymer (of Mitsui Petrochemical

Industries, Ltd., having a vinyl acetate content of 19 wt% and a solid content of 40 wt%), 50 parts by weight of the A-100 a-olefin copolymer (of Mitsui Petrochemical Industries, Ltd., having a solid content of 40 wt%), and 40 parts by weight of the Adecabontine HUX-380 polyurethane (of Asahi Denka Kogyo Co., having the main structure of a polyester and a solid content of 38 wt%) were used and isopropyl alcohol was not added.
The composition of the flame retardant is shown in Table 1 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 3.
[0026] Example 6
A flame retardant for mesh sheets was obtained in the same manner as in Example 1 except that 100 parts by weight of the S-752 ethylene-vinyl acetate copolymer (of Sumitomo Chemical Company, Ltd., having a vinyl acetate content of 90 wt% and a solid content of 50 wt%) was used in place of the V-200 ethylene-vinyl acetate copolymer (of Mitsui Petrochemical Industries, Ltd., having a vinyl acetate content of 19 wt% and a solid content of 40 wt%), 138 parts by weight of the Adecabontiter HUX-380 polyurethane (of Asahi Denka Kogyo Co., having the main structure of a pdlyester and a solid content of 38 wt%) and 20 parts by weight of the TCP organic phosphate were added and isopropyl alcohol was not added. The composition of the flame retardant is shown in Table 2.

An imitation gauze fabric of 45 warps/10 cm and 45 wefts/10 cm was woven with a Dobby weaving machine by paralleling 3 multi-filament fibers of 750 denier to coat the fabric and not the multi-filament fibers in Example 1. The weight of the fabric was 225 g/m2.
Thereafter, the fabric was caused to pass through a guide roll into a tank filled with the flame retardant, pinched with a pinch roll, pass into the flame retardant in the tank through a guide roll, squeezed with a squeezing roll and dried with an air blow to remove the flame retardant filled in the weave of the fabric, and gelled In a heating furnace having a temperature gradient of 130°C, 160°C and 180°C, and the coated cloth was taken up by a winder. The coated cloth was caused to pass through a tank filled with the flame retardant and the same procedure was repeated twice to obtain coated cloth having a coating amount of 392 g/m2 (mesh sheet cloth). The cloth was cut to a predetermined size, sewed and subjected to non-shifting
processing to obtain a flameproof mesh sheet. The properties of the mesh sheet are shown in Table 4.
[0027] Example 7
A leno weave fabric of 20 warps/10 cm and 20 wefts/10 cm was woven with a weaving machine by paralleling 3 multi¬filament fibers of 750 denier to coat the fabric and not the multi-filament fibers in the same manner as in Example 6. The weight of the coated fabric was 90 g/m2.
The fabric was coated with the same flame retardant as in Example 6 in the same manner as in Example 6 and gelled

by heating, and the coated cloth having a weight of 185 g/m2 was taken up by a winder. This coated cloth was cut to a predetermined size, sewed and subjected to non-shifting processing to obtain a flameproof mesh sheet for houses having a small number of stories.
The composition of the flame retardant used is shown in
t
Table 2 and the measurement results of the properties of the flameproof mesh sheet for houses having a small number of stories treated with the flame retardant are shown in Table 4.
[0028] Example 8
An imitation gauze fabric of 120 warps/10 cm and 120 wefts/10 cm was woven with a Dobby weaving machine by using 1 multi-filament fiber of 250 denier to coat the fabric and not the multi-filament fiber in the same manner as in Example 6. The weight of the fabric was 66 g/m2.
Thereafter, the fabric was coated with the same flame retardant for mesh sheets as in Example 6 in the same manner as in Example 6 and gelled by heating, and the coated gray cloth having a weight of 117 g/m2 was taken up by a winder.
The cloth was cut to a predetermined size, sewed and subjected to non-shifting processing to obtain a scattering prevention flameproof mesh sheet.
The composition of the flame retardant used is shown in Table 8 and the measurement results of the properties of the scattering prevention flameproof mesh sheet treated with the flame retardant are shown in Table 4,

Example 9
A flame retardant for mesh sheets was produced in the same manner as in Example 1 except that 100 parts by weight of the S-301 ethylene-vlnyl acetate copolymer (a vinyl acetate content of 80 wt% and a solid content of 50 wt%) was used in place of the V-200 ethylene-vinyl acetate copolymer (a vinyl acetate content of 19 wt% and a solid content of 40 wt%), 167 parts by weight of the Adecabontiter HUX-350 polyurethane (having the main structure of a polyester and a solid content of 30 wt%), 3 parts by weight of the Nova Red 120 red phosphorus, 30 parts by weight of the Hostafuram AP-462 ammonium polyphosphate, 20 parts by weight of the CDP organic phosphate (of Daihachi Kagaku Co.) and 100 parts by weight of the Hijilite H-42H ammonium hydroxide were added.
A flameproof mesh sheet was obtained in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant used is shown in Table 2 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 4.
[0030] Example 10
A flame retardant for mesh sheets was produced in the same manner as in Example 1 except that 100 parts by weight of the S-301 ethylene-vinyl acetate copolymer (a vinyl acetate content of 80 wt% and a solid content of 50 wt%) was used in place of the V-200 ethylene-vinyl acetate copolymer (a vinyl acetate content of 19 wt% and a solid content of 40

wt%), 161 parts by weight of the Adecabontiter HUX-386 polyurethane (having the main structure of a polycarbonate and a solid content of 31 wt%), 12 parts by weight of the Nova Red 120 red phosphorus, 20 parts by weight of the Hostafuram AP-462 ammonium polyphosphate, 20 parts by weight of the CDP organic phosphate and 100 parts by weight of the Kisuma-5 magnesium hydroxide were added.
The composition of the flame retardant is shown in Table 2 and a flameproof mesh sheet was obtained in the same manner as in Example 1 except that the above flame retardant was used.
The measurement results of the properties of the flameproof mesh sheet are shown in Table 4,
[0031] Comparative Example 1
A flame retardant having a viscosity of 2,950 cps was obtained in the same manner as in Example 1 except that the TCP organic phosphate was not added in Example 1. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table 5 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.
[0032] Comparative Example 2
A flame retardant having a viscosity of 3,420 cps was obtained in the same manner as in Example 3 except that the TCP organic phosphate was not added in Example 3. A

flameproof mesh sheet was produced in the same manner as in
Example 3 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table
5 and the measurement results of the properties of the
flameproof mesh sheet treated with the flame retardant are
shown in Table 6. i
[0033] Comparative Example 3
A flame retardant having a viscosity of 3,270 cps was obtained in the same manner as in Example 4 except that the TCP organic phosphate was not added in Example 4. A flameproof mesh sheet was produced in the same manner as in Example 4 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table 5 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.
[0034]
Comparative Example 4
A flame retardant having a viscosity of 2,860 cps was obtained in the same manner as in Example 1 except that the amount of the Nova Excel 140 red phosphorus was changed to 1.0 part by weight. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table 5 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 7.

Comparative"Example 5
A flame retardant having a viscosity of 2,430 cps was obtained in the same manner as in Example 1 except that the amount of the Nova Excel 140 red phosphorus was changed to 12 parts by weight and the amount of the TERRAJU-60 ammonium polyphosphate was changed to 8 parts by weight. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table
5 and the measurement results of the properties of the
flameproof mesh sheet treated with the flame retardant are
shown in Table 7.
[0036] Comparative Example 6
A flame retardant having a viscosity of 1,860 cps was obtained in the same manner as in Example 1 except that 40 parts by weight of the TCP organic phosphate was added and isopropyl alcohol was not added. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table
6 and the measurement results of the properties of the
flameproof mesh sheet treated with the flame retardant are
shown in Table 8.
10037] Comparative Example 7
A flame retardant having a viscosity of 2,880 cps was obtained in the same manner as in Example 1 except that 2

parts by weight of the TCP organic phosphate was added. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table 6 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 8.
[0038] Comparative Example 8
A flame retardant having a viscosity of 2,580 cps was obtained in the same manner as in Example 1 except that red phosphorus, ammonium polyphosphate and a phosphate were not used, 20 parts by weight of antimony trioxide and 25 parts by weight of decabromodiphenyl oxide were used, and isopropyl alcohol was not added. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the above flame retardant was used.
The composition of the flame retardant is shown in Table 6 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 8.
[0039] Comparative Example 9
Coated yarn of 2,557 denier was obtained by coating a multi-filament fiber using a 0.6 mm-diameter sizing nozzle in place of a 0.7 mm-diameter sizing nozzle in Example 1. A flameproof mesh sheet was produced in the same manner as in Example 1 except that the coated yarn which was not coated with the flame retardant twice was used.

The composition of the flame retardant is shown in Table 6 and the measurement results of the properties of the flameproof mesh sheet treated with the flame retardant are shown in Table 8.

















(notes)
(1) The amount of each material is expressed in parts by weight based on 100 parts by weight of a resin solid content-
(2) The unit of numerical values of the coated fabrics of Examples 6, 7 and 8 is g/m2.
(3) The fineness of a multi-filament fiber x the number of the fibers in Examples 6, 7 and 8 are 750 x 3, 750 x 3 and 250 X 1, respectively.
(4) The combustion tests of Examples 1, 5, 6, 1, 8 and 9 and Comparative Examples 4, 5, 6, 7, 8 and 9 were based on A-1 method in which heating was carried out for 1 minute and flames were produced after 3 seconds.
(5) A is TERRAJU-60 (of Chisso Corp.).
(6) B is Hostafuram AP 462 (of Hoechst Japan Limited).
(7) C is Hijilite H-42M (of Showa Denko Co.).
(8) D is Kisuma-5 (of Kyowa Kagaku Co.).
(9) The figures in the column of the fineness (De) of the coated yarn and the coated fabric are for coated fabrics in Examples 6, 7 and 8 and coated yarn in other examples.
[0049] Measurement methods of properties
1. Viscosity measurement method
BM type viscometer rotor No. S, revolution of 12 rpm, 25°C
2. Combustion test
Measured in accordance with 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 In accordance with JIS L-1068
4. Amount of HBr gas generated
0.5 g of a sample was taken. This sample was placed in a combustion tube, preheated at 350 to 400*C for 5 minutes and postheated at 800±30'C for 30 minutes, and a combustion gas was collected into a flask filled with a 1/10 N NaOH solution. The quantity of HBr contained in the solution was determined by ion chromatography.
5. Drop impact strength (penetration test)
Measured in accordance with JIS-8952.
A steel tube having an outer diameter of 48.6 mm, 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 moderate D slightly bad (hard) A bad X sticky X X
7. Gloss
excellent ©
good O
moderate D
slightly bad A

bad
[0050] [Effect of the Invention]
The flameproof mesh sheet of the present invention does not generate harmful halogen gas at the time of combustion and is excellent in flame retardancy and satisfactory in terms of drop impact strength.




we claim
[Claim 1] A flame retardant for mesh sheets comprising red phosphorus in an amount of 1.5 to 15 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the solid content of an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt%.
[Claim 2] A flame retardant for mesh sheets prepared by mixing an aqueous dispersion of an a-olefin copolymer having a solid content of 20 to 45 wt% with an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt% in a solid content weight ratio of 10:90 to 70:30 and adding red phosphorus in an amount of 1.5 to 15 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the total resin solid content.
[Claim 3] A flame retardant for mesh sheets prepared by mixing an aqueous dispersion of a polyurethane having a solid content of 25 to 70 wt% with an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt% in a solid content w,eight ratio of 10:90 to 90:10 and

adding red phosphorus in an amount of 1.5 to 15 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the total resin solid content.
[Claim 4] A flame retardant for mesh sheets prepared by mixing an aqueous dispersion of an a-olefin copolymer having a solid content of 20 to 45 wt% and an aqueous dispersion of a polyurethane having a solid content of 25 to 70 wt% with an aqueous dispersion of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 95 wt% and a resin solid content of 25 to 75 wt% in a solid content weight ratio of 10:10:80 to 50:80:10 and adding red phosphorus in an amount of 1,5 to 5 parts by weight, an ammonium polyphosphate compound in an amount of 10 to 50 parts by weight and an organic phosphate in an amount of 3 to 30 parts by weight based on 100 parts by weight of the total resin solid content.
[Claim 5] The flame retardant for mesh sheets of any one of claims 1 to 4, wherein red phosphorus is micro-capsulated.
[Claim 6] The flame retardant for mesh sheets of any one of claims 1 to 5, wherein the ammonium polyphosphate compound is micro-capsulated.
[Claim 7] The flame retardant for mesh sheets of any one of claims 1 to 6, wherein the organic phosphate is an organic phosphate containing no elemental halogen.
[Claim 8] A flame retardant for mesh sheets prepared by mixing a metal hydroxide in an amount of 30 to 150 parts by weight based on 100 parts by weight of the solid content of

the aqueous dispersion resin of the flame retardant for mesh sheets of any one of claims 1 to 7 with the flame retardant,
[Claim 9] The flame retardant for mesh sheets of claim 8, wherein the metal hydroxide is magnesium hydroxide and/or aluminum hydroxide.
[Claim 10] A flameproof mesh sheet woven out of coated yarn which is impregnated with the flame retardant for mesh sheets of any one of claims 1 to 9 and heated.
[Claim 11] The flameproof mesh sheet of claim 10, wherein the coated yarn is a multi-filament fiber having 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 an elongation at break of 14 to 45 %.
[Claim 12] A flameproof mesh sheet prepared by impregnating a mesh sheet fabric woven out of multi-filament fibers with the flame retardant for mesh sheets of any one of claims 1 to 9 and heating.
[Claim 13] Tlie flameproof mesh sheet of claim 12, wherein the mesh sheet fabric woven out of multi-filament fibers is a mesh sheet fabric prepared by paralleling 1 to 4 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 an elongation at break of 14 to 45 % and leno weaving them with a weaving machine, and has a mesh length of 10 to 140 warps/10 cm and 10 to 140 wefts/10 cm.
[Claim 14] The flameproof mesh sheet of any one of claims 10 to 13, wherein the amount of the flame retardant for mesh sheets of any one of claims 1 to 9 used to

of the multi-filament fibers is 60 to 350 parts by weight based on 100 parts by weight of the multi-filament fibers or the mesh sheet fabric.
15. A flame retardant for mesh sheets substantially as hereinbefore described-


Documents:

2745-mas-1998-abstract.pdf

2745-mas-1998-claims filed.pdf

2745-mas-1998-claims granted.pdf

2745-mas-1998-correspondnece-others.pdf

2745-mas-1998-correspondnece-po.pdf

2745-mas-1998-description(complete)filed.pdf

2745-mas-1998-description(complete)granted.pdf

2745-mas-1998-form 1.pdf

2745-mas-1998-form 19.pdf

2745-mas-1998-form 26.pdf

2745-mas-1998-form 3.pdf

2745-mas-1998-form 4.pdf

2745-mas-1998-other documents.pdf


Patent Number 212459
Indian Patent Application Number 2745/MAS/1998
PG Journal Number 07/2008
Publication Date 15-Feb-2008
Grant Date 03-Dec-2007
Date of Filing 08-Dec-1998
Name of Patentee SAIJI NOZAKI
Applicant Address 2063, AIMOTOSHIN, UNAZUKI-MACHI, SHIMONIIKAWA-GUN, TOYAMA-KEN,
Inventors:
# Inventor's Name Inventor's Address
1 KUNIAKI KAMIYA 1-13-20, MINAMISENBA, CHUO-KU, OSAKA-SHI, OSAKA-FU,
PCT International Classification Number B23 B 9/04
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA