Title of Invention	LAMINATE BOARD AND PROCESS OF PREPARATION THEREOF
Abstract	The present disclosure provides a laminate board that is resistant to water absorption, rupture, abrasion, steam, cracks, cigarette burns and stains. The laminate board comprises of core board impregnated with phenol formaldehyde resin; at least two barrier layers wherein one barrier layer positioned above and at least one barrier layer positioned below said core board and at least two abrasion resistant layers, wherein one abrasion resistant layer is positioned at outer surface of said barrier layers. The barrier layers and the abrasion resistant layers are impregnated with melamine formaldehyde resin or urea formaldehyde resin. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a result of Impregnation with PF resin and MF or UF resin. The present disclosure further provides a process of preparation of said laminate board. The process involves use of cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure.

Title of Invention

LAMINATE BOARD AND PROCESS OF PREPARATION THEREOF

Abstract

The present disclosure provides a laminate board that is resistant to water absorption, rupture, abrasion, steam, cracks, cigarette burns and stains. The laminate board comprises of core board impregnated with phenol formaldehyde resin; at least two barrier layers wherein one barrier layer positioned above and at least one barrier layer positioned below said core board and at least two abrasion resistant layers, wherein one abrasion resistant layer is positioned at outer surface of said barrier layers. The barrier layers and the abrasion resistant layers are impregnated with melamine formaldehyde resin or urea formaldehyde resin. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a result of Impregnation with PF resin and MF or UF resin. The present disclosure further provides a process of preparation of said laminate board. The process involves use of cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure.

Full Text	TECHNICAL FIELD The present disclosure relates to laminate board that is resistant to water absorption rupture abrasion, steam, cracks, cigarette burns and stains and the process of preparing the laminate board. BACKGROUND Particle boards are panel-like products made by bonding wooden materials with an adhesive. Most of such particle boards have a three layer construction consisting mainly of a core layer and two face layers formed on both, front and back, sides of the core layer. The core layer comprises relatively large sized wooden materials hence creating visually recognizable voids. On the contrary, the face layers comprise relatively small sized wooden materials hence being close structure. Such particle boards are made by supplying wooden materials with a spray of a urethane adhesive, forming, and pressurizing them with heating. As the particle board is poor in the function of resistance to water, its water-content gradient may cause deflections and dimensional changes of its structure or its water remaining may result in the development of mold and the decomposition of wooden constituents. Products coated with thermosetting laminates are frequent today. They are foremost used where the demand for abrasion resistance is high, but also where resistance towards different chemicals and moisture is required. As an example of such products floors, floor headings, table tops, work tops and wall panels can be mentioned. The laminated particle boards most often consists of a carrying base with a decor sheet and one or more wear layers placed closest to the surface. The decor sheet can be provided with a desired decor or pattern. The most frequent patterns usually represent the image of different kinds of wood or minerals such as marble or granite. The most common way of achieving a laminated particle board is by first manufacturing the thermosetting laminate of a number of paper layers impregnated with melamine formaldehyde resin and then to glue this thermosetting laminate onto a core for example fibre board or particle board. It is also known to feed a few melamine formaldehyde impregnated paper webs together with sheets of particle or fibre board through a continuous laminate press. SUMMARY The present disclosure provides a laminate board comprising Phenol Formaldehyde (PF) coated core board; at least one Barrier layer impregnated with Melamine Formaldehyde (MF) resin or Urea Formaldehyde (UF) resin placed on either side of the core board; at least one Abrasion resistant layers impregnated with MF resin or UF resin placed on either side of the Barrier layer. The three layers are inter-linked to each other for good bonding and developing resistance to factors such as swelling in water/ water absorption, rupture, abrasion, steam, crack, cigarette burn and stain. The thickness of the PF coated core board is 0.10mm, the thickness of the barrier layer impregnated with MF resin or UF resin is 0.10mm, and the thickness of the abrasion resistant layer impregnated with M.F Resin or UF resin is 0.15mm. The present disclosure provides a laminate board that has accurate matching. The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a rush of impregnation with PF resin and MF resin or UF resin. Therefore, the present disclosure provides solution to the problems of deviation in different layers when the layers are subjected to lamination leading to distorted laminate boards. The present disclosure provides a laminate board using cement bonded particle board technique. The present disclosure provides a process of preparation of said laminate board comprising sanding said core board, filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin; placing at least one barrier layer above said core board and at least one barrier layer below said core board, wherein said barrier layer is impregnated with a meiamine formaldehyde resin or a urea formaldehyde resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a meiamine formaldehyde resin or a urea formaldehyde resin; assembling said core board, said barrier layers and said abrasion resistant layers to obtain a book system; subjecting said book system to a suitable specific pressure and suitable temperate for suitable time followed by cooling and trimming undesired edges of said book system to obtain said laminate board. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS Figure 1; Layer assembly of the laminate board DETAILED DESCRIPTION The laminate board of the present disclosure has (1) PF coated core board; (2) at least one Barrier layer impregnated with MF resin or UF resin placed on either side of the core board; (3) at least one Abrasion resistant layers impregnated with MF resin or UF resin placed on either side of the Barrier layer as provided in Figure 1. The three layers are inter-linked to each other for good bonding and developing resistance to factors such as swelling in water/ water absorption, rupture, abrasion, steam, crack, cigarette bum and stain. The thickness of the P.F coated core board is 0.10mm, the thickness of the barrier layer impregnated with M.F resin or UF resin is 0.10mm, and the thickness of the abrasion resistant layer impregnated with M.F Resin or UF resin is 0.15mm. The present disclosure provides that the core board is laminated with decorative paper of minimum gram per square meter (gsm). The term "thermosetting" refers to compounds that soften when initially heated, but hardens permanently once it has cooled. Thermosetting materials are made of long-chain polymers that cross-link with each other after they have been heated, rendering the substance permanently hard. In the present disclosure, PF, MF and UF are the thermosetting resins used. The present disclosure further relates to a composition of the resin that is applied to the surface of the core board. The core board such as cement bonded wooden particle board is subjected to periodic heating and cooling. The present disclosure provides a laminated cement bonded wooden particle board which has highly decorative having good texture, gloss and smooth finish. The terms "plain board", and "core board" are used interchangeably in the present disclosure. The "plain board" or "core board" is used as a starting material for preparing the laminate. The "plain board" and "core board" includes but is not limited to saw board, fiber board, particle board, cement bonded fiber board and cement bonded wooden particle board. The term Phenol Formaldehyde resin is also referred to as PF resin in the present disclosure. The term Melamine Formaldehyde resin is also referred to as MF resin in the present disclosure. The term Urea Formaldehyde resin is also referred to as UF resin in the present disclosure. The terms "base paper", "decor paper" and decor sheet" are used interchangeably herein after. The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation. The term "abrasion resistant layer" refers to decor sheets impregnated with MF resin or UF resin as this layer provides abrasion resistance to the laminate board of the present disclosure. The term "barrier layer" refers to sheets, preferably one or more Kraft sheets impregnated with MF resin or UF resin. The terms "Phenol resin" and "Phenol formaldehyde resin" are used interchangeably herein after. IS 2380: Part 1 to 23 refers to Indian Standards for methods of test for wood particle boards and boards from other lignocellulosic materials. I.S 14276 refers to Indian Standard for Cement Bonded Wood Particle Board specification (Plain). IS 12823 refers to Indian Standard for "Wood Products - Prelaminated Particle Boards - Specification" In the present disclosure, the singular forms "a", "an", and "the" include plural reference, unless the context clearly dictates otherwise. Thus, for example, a reference to "sheet" includes a plurality of sheets, a reference to "layer" also includes a plurality of layers and a reference to "paper" is also a reference to one or more papers thereof known to those skilled in the art. Similar syntactic principal also applies to other components of the disclosure such as board. In an embodiment the present disclosure provides a laminate board that is resistant to water absorption, rupture, abrasion, steam, cracks, cigarette bums and stains, said laminate board comprising; a core board impregnated with a phenol formaldehyde resin; at least two barrier layers, wherein at least one barrier layer is positioned above said core board and at least one barrier layer positioned below said core board, wherein each of said barrier layers are impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and at least two abrasion resistant layer, wherein at least one abrasion resistant layer is positioned over outer surface of said barrier layers, wherein each of said abrasion resistant layers is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin. In another embodiment the present disclosure provides a laminate board that has density not less than 1250 kg/m^ In further another embodiment the present disclosure provides a laminate board that has moisture content in the range of 6 to 12 percent by weight of the board. In another embodiment the present disclosure provides a process of preparation said laminate board, said method comprising; sanding said core board, optionally filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin; placing at least one barrier layer above said core board and at least one barrier layer below said core board, wherein said barrier layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; assembling said core board, said barrier layers and said abrasion resistant layers to obtain a book system; subjecting said book system to a suitable specific pressure and suitable temperate for suitable time followed by cooling and trimming undesired edges of said book system to obtain said laminate board as shown in Figure 1. In yet another embodiment the present disclosure provides process of preparation said laminate board, wherein the core board includes but is not limited to saw board, fiber board, particle board, cement bonded particle board or cement bonded fiber board. The dents in the core boards irrespective of the type of board are filled with cement paste. The process involves use of novel cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure. In The process involves use of cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure. In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said sanding is carried out at air pressure in the range of 2 to 5 kg/cm^. In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable specific pressure is in the range of 30-40 Kg/cm^ In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable temperate is in the range of I25°C-140°C. In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable time is in the range of 20-25 min. In an embodiment of the present disclosure the laminate board has PF coated core board; at least one Barrier layer impregnated with MF resin or UF resin placed on either side of the core board; at least one Abrasion resistant layer impregnated with MF resin or UF resin placed on either side of the Barrier layer. In an embodiment of the present disclosure the Barrier layer is impregnated with MF resin. In another embodiment of the present disclosure the Barrier layer is impregnated with UF resin. In yet another embodiment of the present disclosure the Abrasion resistant layer is impregnated with MF resin. In yet another embodiment of the present disclosure the Abrasion resistant layer is impregnated with UF resin. In an embodiment of the present disclosure, there are more than one barrier layer placed on either side of the core board. In another embodiment of the present disclosure, there is one barrier layer placed on either side of the core board. In still another embodiment of the present disclosure, there are more than one abrasion resistant layers placed over the barrier layer. In still another embodiment of the present disclosure, there is one abrasion resistant layer placed over the barrier layer. In an embodiment of the present disclosure, the barrier layer comprises of Kraft sheets impregnated with Melamine formaldehyde (MF) resin. In another embodiment of the present disclosure, the barrier layer comprises of Kraft sheets impregnated with Urea formaldehyde (UF) resin. In an embodiment of the present disclosure, the abrasion resistant layer comprises of decor sheets impregnated with Melamine formaldehyde (MF) resin. In an embodiment of the present disclosure, the abrasion resistant layer comprises of decor sheets impregnated with Urea formaldehyde (UF) resin. In an embodiment of the present disclosure, the laminate board can be used for several applications such as constructing floors, floor headings, table tops, work tops, wall panels, doors, windows, work stations and partitions. The present disclosure provides preparation of laminate board wherein core (plain) boards were selected based on the desired finished laminate board thickness to be prepared. The core boards were sanded in sanding machine with 60 & 100 Grit sanding beU to obtain finished surface and uniform thickness. After sanding, the sanded boards were inspected and defect free sanded boards were collected. If necessary, dents on the sanded board surface was filled with cement by adding slight water. Phenol formaldehyde (PF) Resin is applied on the both sides of the sanded board. Tissue/Barrier and decor paper impregnated in MF resin are placed over the PF resin coated sanded board and assembled into a book system. The assembled boards (book system) as a lot were fed into a multi day light press and specific pressure of 30 to 40 Kg/Cm^ was applied wherein a temperate was maintained at about I25°C to 140°C for 20 to 25 minutes cycle time. The boards (book system) were cooled to the temperature about 40° C. After cooling, boards (book system) were removed from the press. The assembled boards (book system) were separated from the lot and excess paper edges of each of the assembled boards were trimmed to obtain the laminated board. The layer assembly of the laminate is shown in Figure 1. In an embodiment of the present disclosure, the PF resin is used as binding agent that helps in binding the other layers placed on either sides of the board. The other layers include the barrier layer positioned above and below said plain board coated with PF resin. In another embodiment of the present disclosure, the barrier layer comprises of one or more Kraft sheets impregnated with a thermosetting resin. Another embodiment of the present disclosure provides that the thermosetting resin is Melamine formaldehyde (MF) resin. Yet another embodiment of the present disclosure provides that the thermosetting resin is Urea formaldehyde (UF) resin. In another embodiment of the present disclosure, the barrier layer impregnated with MF resin serves as water absorption resistant layer. In another embodiment of the present disclosure, the decor sheets impregnated with thermosetting resin is abrasion resistance. The decor sheets impregnated with thermosetting resin is also referred to as the abrasion resistant layer. In an embodiment, the present disclosure provides laminate board comprising core board ranging from 10 to 13Kgs, Base Paper coated with thermosetting resin as exemplified ranging from 0.150 to 0.200kg, P.F resin ranging from 0.150 to 0.200 Kgs and M.F resin or UF resin or combination thereof ranging from 0.750 to 1.000 kg. In another embodiment, the present disclosure provides that the base papers refer to barrier layer and abrasion resistant layer. In another embodiment of the present disclosure, the laminate board has accurate matching. The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a result of impregnation with PF resin and MF resin or UF resin. In another embodiment of the present disclosure, the sanding is done using belts having dimension in the range of 50 to 120 grits. In another embodiment of the present disclosure, the barrier layer comprises of Kraft sheet impregnated with MF resin or UF resin and the abrasion resistant layer comprises of decor sheet impregnated with MF resin or UF resin. In still another embodiment of the present disclosure, the laminate board has accurate matching due to compatibility between the PF resin coated plain board and MF resin or UF resin impregnated other layers, namely the barrier layer and the abrasion resistant layer. In yet another embodiment of the present disclosure, felt cloth and graphite pad are used in sanding of the core board before impregnating the PF resin on the core board. In another embodiment of the present disclosure the laminate boards are resistant to steam as per IS: 12823 and exhibits only slight change in color after exposing the laminate board to steam for a long duration, after about 2 hrs. In an embodiment of the present disclosure the laminate boards are crack resistant. The laminate boards when subjected to high stress show crack after 24 hours duration on the surface. In another embodiment of the present disclosure the laminate boards are abrasion resistant as per IS2380. In yet another embodiment of the present disclosure the laminate boards have pH in range from 11 to 13. In still another embodiment of the present disclosure the laminate boards have modulus of elasticity of the laminate board not less than 3000 N/mm^ complying with IS: 14276. In another embodiment of the present disclosure the laminate boards have screw withdrawal strength at face was not less than 1250 N and at edges was not less than 850 N. In an embodiment of the present disclosure the laminate boards have tensile strength PPler to surface not less than 0.2 N/mm^ complying with IS: 14276. The tensile strength PPler to surface after ageing test of the laminate board was not less than 0.2 N/mm^ complying with IS: 14276. In still another embodiment of the present disclosure the laminate boards have modulus of rupture not less than 11 N/mm^ complying with IS: 14276. In yet another embodiment of the present disclosure the laminate boards have water absorption resistance or swelling in thickness of maximum 5% after 2 hrs complying with IS: 14276. The water absorption by the laminate boards is not to exceed the prescribed limits as per IS: 14276, Maximum 7% after 2 Hrs, and Maximum 15% after 24 Hrs immersion in water. In further another embodiment of the present disclosure the laminate boards exhibit average moisture content in the range of 6 to 12 percent by weight of the laminate complying with IS: 14276. In further another embodiment of the present disclosure the laminate boards have * density of not less than 1250 Kg/m^ The laminate boards obtained from the above mentioned process can have density variation that is permissible to meet IS2380 requirements. While various embodiments and/or individual features of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. As will be also be apparent to the skilled practitioner, all combinations of the embodiments and features taught in the foregoing disclosure are possible and can resuh in preferred executions of the present disclosure. EXAMPLES The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and the description to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention nor are they intended to represent that the experiments below are all and only experiments performed. EXAMPLE 1 PREPARATION OF LAMINATE BOARD 1. Preparation of pre-laminate board A. Selection of core/plain boards The plain board which herein is exemplified by cement bonded pre-laminated particle board was selected at random. The selected boards were tested as specified in I.S 2380 for requirements such as length, width, thickness, edge straightness and squareness. I.S 2380 refers to standard methods of test for Wood Particle Boards and Boards from other lignocellulosic materials. The plain board must be 1.0 to 2.0 mm thickness more than the desired laminate board. That means the sanding allowance must be given 1.0 to 2.0mm to get the uniform surface without any unsanding patches. After selecting the proper boards for sanding, the boards were kept in a lot form (not more than one Clamp at a time i.e. 960mm ht) and placed on the stacking table. B. Sanding Two different operations were employed for sanding, namely, 1) Rough operation with 50/60 Grit Sanding belts of size 1350mm X 2800mm. 2) Fine operation with 100/120 Grit Sanding belts of size 1350mmX 2800mm. For sanding, the sanding machine was made ready. Sanding operation is dependent on the thickness of the plain board. The thickness of the saw boards was observed and the machine was adjusted accordingly to cut maximum 0.5mm and cut on each motor (top and bottom). The load was observed while the sanding operation was going on and the speed of the conveyor was adjusted such that that it did not take the load of more than 150 Amps. The boards thickness was checked at different points (longitudinal & cross sectional). The variation of thickness should not be ± 0.1 of standard thickness. The standard thickness of the plain board for rough operation was 0.2mm more than the final lamination board. The dust suction of the sanding checked properly and thorough air cleaning is required at proper intervals to get more life of the bolts and to avoid the breakdowns of the machine. Sanding operation First operation The sanding machine was thoroughly cleaned. The belts were checked for damages and mounted into the machine by properly observing the direction of the behs. For rough operation 50 or 60 Grit belts were used. The air pressure was checked properly. The top and bottom air pressures were adjusted to not less than 4.5 Kgs/Cm^ and 2.0 Kgs/Cm^ respectively. The top and bottom oscillations were checked properly before starting the machine. The first motor was started with on-off by observing the oscillation. If the oscillation was proper, the operation was continued to take full speed. The same step can be repeated for the second motor. Therefore, the above steps ensured that the sanding machine was ready for operation. Second operation: Preparation of Graphite Pads The frame to be inserted in the machine was thoroughly cleaned and the suitable felt cloth (4 to 8mm) was mounted into the frame with suitable adhesive. Graphite paper was attached on the felt cloth with suitable adhesive and the frame was allowed to stand for some time for proper setting. The frame with this attachment was properly put into the machine in the grove. 100/120 Grit belts were mounted in the drums and the graphite pads must be inside the belts. The remaining operation was continued like the first operation and the cutting of the board with the sanding belt was not more than 0.1mm at each motor. The ampere range was maintained by adjusting the speed of the machine such that ampere range was not more than 100 Amps. The thickness of the board was observed and the standard/required thickness for lamination with in the levels of less than 0.1 to 0.2 mm variation within the board was maintained. C. Inspection and Segregation of the sanded boards For selection of sanded board for preparing lamination board, each board was inspected for physical verification. The lab reports of the mechanical properties of the laminate board were studied. The following points were considered at the time of inspection: 1. The board were defect free (without any damages); 2. The boards were within the tolerance of length, width and thickness; 3. Surface was smooth without any defects; 4. No unsanded portion was accepted on either side of the surface; 5. No Dents were accepted 6. Minor dents/holes were covered with cement filling. 7. No over size chips were allowed on the surface. 2. Preparation of Resins Preparation of Phenol Formaldehyde (PF) Resin The raw materials used for preparation of PF resin are: (a.) Phenol (Granules 100% Pure); (b.) Formalin (Colorless with 36-37%); and (c.) Methanol. Batch Preparation: Phenol = 215 Kgs and Formalin =215 Kgs 1:1 Ratio Methanol =185 Kgs Catalyst =10 Kgs Formalin of 215 Kgs was charged in the Kettle Reactor and 215 Kgs of Phenol was added through vacuum suction and the mixture was stirred. Liquid ammonia was added for 10 Kgs to maintain the pH at 7.0. Steam heating was started to allow the temperature to go up to 75° C which was attained within 15 to 20 min. The steam heating was stopped and the exothermic reaction levels were allowed to advance further. The temperature of the above mixture was maintained at 100° C and the reaction was stopped. This reaction approximately continues for 3.0 hrs. The attainment of polymerization to requisite levels was confirmed by testing the set time and start time. Vacuum distillation was performed to remover the water quantity of 140 Kgs. The distillation was stopped followed by addition of 185 kgs of methanol after which cooling was started. The pH was adjusted and maintain at about 8.0. The liquid is in stringing form semi solid starts. To store it in drums, solvent was added to maintain the viscosity. Resin viscosity was maintained when it was checked with B4 Ford cup. The PF resin obtained from the above process had the following property: Viscosity 15 Sec with B-4 Ford cup, specific gravity-1.00 to 1.07, Geltime at 150°C - 90 to 100 Sec, pH 7.0 to 8.0. Preparation of Melamine Formaldehyde (MF) Resin Formalin = 150Kgs. NaOH:NBA = 5 Kgs. Melamine = 125 Kgs. MEG : 12 Kgs. Formalin was charged in the reactor and then melamine was added with continuous stirring. The ratio of melamine to formalin was maintained as 1:2.2. The pH was adjusted to 8.5 to 9.0 by the addition of 10% caustic solution. By continuous stirring heating was started. The temperature was maintained at 95° C by steam heating. The polymerization reaction was advanced further. The heating was continued till the required polymerization level was attained. A precipitation test water tolerance was measured when the ratio of 1:8 is obtained. The heating is stop and cooling started. All additives like Urea, MFG, NBA, modifier as mentioned above were added and the PH was maintained at around 9.0. The mixture was continued till the resin attained temperature of about 40° C. The final yield of the MF resin was 304 kg. Similarly, Urea Formaldehyde (UF) resin can be prepared and by using the conventional processes. 3. Preparation of Laminate board The inspected sanded boards obtained by the above mentioned process were selected as per requirement. The surface of the sanded boards was observed and the dents if any on the surface were covered with semisolid cement. The phenol resin (180 gm - 200 gm) was coated uniformly on both the surface of the sanded board with the help of spray gun and allowed it to rest in the stand for air drying. Impregnation Impregnation is the process of deposition of MF Resin on the base paper in dry condition. The base paper in the present disclosure is exemplified by Kraft paper and decor paper. The decorative paper required for lamination was loaded on a metal stand in front of the resin tray. The paper was arranged such that it passed through the ok rollers and into the turf and lead to parallel rod which passed through hot air zone. MF resin was loaded into the tray and the above decor paper was passed through the resin and the squeezing rollers. The speed of the machine was adjusted such that the base paper was allowed to absorb the required quantity of resin and the squeezing rollers were adjusted such that to squeezed the excess quantity of resin. MF resin absorbed paper was made to travel in the hot air dryer and cooling rollers. The MF resin absorbed paper was cut to the required sizes through the cutter. The paper was made to travel in the hot air zone I & II at temperature of 135° C to 140° C by floating media without touching to any sides. The speed of the machine was adjusted to maintain the volatile content of the paper at 6.0 to 7.0. The stack of the treated papers, namely, decor layer impregnated with MF resin was stored in A.C room. The decor layer impregnated with MF resin is referred to as abrasive resistant layer. Similarly, barrier layer was prepared by impregnating one or more kraft sheets with MF resin by the process mentioned above. Assembling of Book System in forming station A Book system was assembled on a carrier plate in the forming station. The Book system contains 6 layers of padding paper (200 gsm), S.S plate of mat mould followed by MF coated Decorative paper, MF coated Tissue paper, PF coated Board and MF coated tissue paper and coated Decorative paper or coated back up white paper, S.S.Mould and Padding paper. Finally place a balancing 3mm S.S plate over the padding paper. The total formed book system was taken into loader. The same process was continued for eight day lights. The eight day book system which was ready in loader was pushed into Hydraulic press for further processing. Hydraulic Press Hydraulic press having eight day lights was thoroughly cleaned with air before taking the book system into press. The temperature was raised to 100° C by steam heating maintained the pressure of steam at 2.0 to 2.5 Kg. The book system was taken into the press. The press was closed and hydraulic pressure was maintained at 105 Kg/CM^ to 115 Kg/CM^ which is app. equivalent to 30 Kg/cm^ (specific pressure). Heating was needed to raise the temperature to 125°C ± 2°C. Heating cycle was continued for 20 min for curing of impregnated material (I.M) such as barrier and decor layers. The heating and cooling cycle was started for 15 min. When the plates reached 40°- 45°C, the press was opened. All the light book systems were taken into un-loader. One by one book system was taken into forming station and the boards were deputed from the moulds. The boards are stacked properly. The edges of the book system was cleaned and inspected for physical defects on the surface. The laminate boards so obtained were properly packed by pasting stickers and kept ready for dispatch. EXAMPLE 2 Properties of the laminate board From the laminate board obtained above, portions of 150mm were cut from the edges. The processed laminate boards were tested as per conditions specified in l.S 2380. l.S 2380 refers to standard methods of test for wood particle boards and boards from other lignocellulosic materials. l.S 14276 refers to Cement Bonded Wood Particle Board specification (Plain). The laminate board obtained was tested to determine the density, moisture content, water absorption property, swelling in water, modulus of rupture, tensile strength PPler to surface, tensile strength PPler to the surface after ageing test, screw withdrawal strength, modulus of elasticity and pH value. Density of laminate boards There were three laminate boards of dimension 75mm wide and 150mm long in full thickness taken as test samples. The density of the boards determined for each test specimen was not less than 1250 Kg/m\ The laminate boards obtained from the above mentioned process can have density variation that is permissible to meet 1S2380 requirements Moisture content of the laminate board There were three laminate boards of dimension 75mm wide and 150mm long in full thickness taken as test samples. The laminate boards of all other possible dimensions are also a subject matter encompassed by the present disclosure. The laminate boards exhibited average moisture content in the range of 6 to 12 percent by weight of the laminate and complies with IS: 14276. Water absorption property of the laminate board There were three laminate boards of 300mm X 300mm dimension taken as test samples. The laminate boards of other dimensions are also a subject matter encompassed by the present disclosure. The water absorption was determined for each test specimen and the average value was not to exceed the prescribed limits as per IS: 14276, Maximum 7% after 2 Hrs, and Maximum 15% after 24 Hrs immersion in water. Laminate boards water swelling property There were three laminate boards of size 200mm X 100mm in full thickness taken as test samples. The swelling in thickness shall be determined for each test specimen for 2 hrs soaking in water and the average value shall not exceed the specified limits specified as per IS: 14276, maximum 5% after 2 hrs. Modulus of rupture of the laminate board There were three laminate boards of size 200mm X 100mm in full thickness taken as test samples. The modulus of rupture was determined for each test specimen and the average value was not less than 11 N/mm^ complying with IS: 14276. Tensile strength PPler to surface of the laminate board There were three laminate boards of size 50mm X 50mm in full thickness taken as test samples. The tensile strength perpendicular to surface was determined for each test specimen and the average value was not less than 0.3 N/mm^ complying with IS: 14276. Tensile strength PPIer to the surface after ageing test of the laminate board There were three laminate boards of size 50mm X 50mm in full thickness taken as test samples. The tensile strength PPler to surface was determined for test specimen after subjecting the test specimens in accordance with the method prescribed in I.S 2380. The test specimens were immersed in water at 27 ± 2° C and water is brought to boiling and kept at boiling temperature for two hours. The test specimens were then cooled in water to 27 ± 2° C and tested for tensile strength PPler to the surface. The tensile strength PPler to surface was determined for each test specimen and the average value was not less than 0.2 N/mm^ complying with IS: 14276. Screw withdrawal strength of the laminate board There were three laminate boards of size 150mm X 75mm in full thickness taken as test samples. The screw withdrawal strength of the laminate board was in concordance with IS: 14276. The screw withdrawal strength was determined for each test specimen and the average value at face was not less than 1250 N and at edges was not less than 850 N. Modulus of Elasticity of the laminate board There were three laminate boards of size 50mm X 50 mm in full thickness taken as test samples. The three test specimens exhibited modulus of elasticity conforming to the requirement specified in I.S 2380. The modulus of elasticity of the laminate board was determined for each test specimen and the average value was not less than 3000 N/mm^ complying with IS: 14276. pH value of the laminate board There were three laminate boards of size 150mm X 75mm in full thickness taken as test samples. The laminate boards of other dimensions are also encompassed by the present disclosure. The pH of the laminate boards was found to range from 11 to 13. Abrasion Resistance of the laminate boards The abrasion resistance of the laminate boards was determined by IS2380and was found to be 450 Revolutions complying with IS: 12823. Steam resistance of the laminate boards The resistance of the laminate boards to steam was determined for each test specimen in accordance with the method prescribed by IS2380. There were laminate boards of size 100mm X 100mm taken as test samples. The laminate boards were place on conical flask filled with water up to 100 C.C on the hot plate. The mouth of the conical flask was covered with the specimen such that the surface of the laminate board to be tested faced the conical flask. A clamp was used to secure laminate board from falling down. The water in the conical flask was heated using an electric heater. The water was heated for a period of 2 hours after the water start boiling. The steam cones contact the board surface and escape into atmosphere. The surface of the laminate board facing the conical flask was observed. The laminate boards did not show any sign of blaster. The laminate boards were tested for determination of change in surface finish. There laminate boards exhibited slight change in color after a long duration, after about 2 hrs as per IS: 12823. Crack resistance of the laminate boards Crack resistance of the laminate board was determined for each test specimen. The test specimen of size 100mm X 100mm was subjected to a temperature of 70 ± 2° C. The specimens after 24 hours duration were observed for cracks on the lamination surface of the boards. The laminate boards did not exhibit any sign of cracks or de-lamination as per IS: 12823. Cigarette resistance of the laminate boards Resistance to cigarette burn was determined by placing a slowing cigarette horizontally on the laminate boards of size 200mm X 200mm for 60 seconds. The area where the cigarette was contacted with the laminate board was cleaned with water or a suitable solvent. The color change in the cigarette contacted area was observed. The laminate boards did not leave any mark or stain on the specimen after cleaning with water or solvent complying with IS: 12823. Stain resistance of the laminate boards Resistance to stain was determined for the laminate boards. The stains on the laminate board were easily removed by cleaning with water, solvent or detergent thereby complying with IS: 12823. claim 1. A laminate board that is resistant to water absorption, rupture, abrasion, steam, cracks, cigarette burns and stains, said laminate board comprising a core board impregnated within a phenol formaldehyde resin; at least two barrier layers, wherein at least one barrier layer is positioned above said core board and at least one barrier layer positioned below said core board, wherein each of said barrier layers are impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and at least two abrasion resistant layer, wherein at least one abrasion resistant layer is positioned over outer surface of said barrier layers, wherein each of said abrasion resistant layers is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin. 2. The laminate board as claimed in claim 1, where said laminate board has density not less than 1250 Kg/m3. The laminate board as claimed in claim 1, where said laminate board has moisture content in the range of 6 to 12 percent by weight of the board. 4. The laminate board as claimed in claim 1, wherein said core board is selected from a group comprising saw board, fiber board, particle board, cement bonded particle board and cement bonded fiber board. 5. A process of preparation said laminate board of claim 1, said method comprising; sanding said core board, filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin; placing at least one barrier layer above said core board and at least one barrier layer below said core board, wherein said barrier layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde . resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; assembling said core board, said barrier layers and said abrasion resistant layers; subjecting the above assembly to a suitable specific pressure and suitable temperate for suitable time followed by cooling and optionally trimming undesired edges to obtain said laminate board. 6. The process as claimed in claim 5, wherein said sanding is carried out at air pressure in the range of 2 to 5 kg/cm'‘. 7. The process as claimed in claim 5, wherein said suitable specific pressure is in the range of 30-40 Kg/cm’. 8. The process as claimed in claim 5, wherein said suitable temperate is in the range of 125°C-140°C. 9. The process as claimed in claim 5, wherein said suitable time is in the range of 20-25 min.

Full Text

TECHNICAL FIELD
The present disclosure relates to laminate board that is resistant to water absorption rupture abrasion, steam, cracks, cigarette burns and stains and the process of preparing the laminate board.
BACKGROUND
Particle boards are panel-like products made by bonding wooden materials with an adhesive. Most of such particle boards have a three layer construction consisting mainly of a core layer and two face layers formed on both, front and back, sides of the core layer. The core layer comprises relatively large sized wooden materials hence creating visually recognizable voids. On the contrary, the face layers comprise relatively small sized wooden materials hence being close structure. Such particle boards are made by supplying wooden materials with a spray of a urethane adhesive, forming, and pressurizing them with heating. As the particle board is poor in the function of resistance to water, its water-content gradient may cause deflections and dimensional changes of its structure or its water remaining may result in the development of mold and the decomposition of wooden constituents. Products coated with thermosetting laminates are frequent today. They are foremost used where the demand for abrasion resistance is high, but also where resistance towards different chemicals and moisture is required. As an example of such products floors, floor headings, table tops, work tops and wall panels can be mentioned. The laminated particle boards most often consists of a carrying base with a decor sheet and one or more wear layers placed closest to the surface. The decor sheet can be provided with a desired decor or pattern. The most frequent patterns usually represent the image of different kinds of wood or minerals such as marble or granite. The most common way of achieving a laminated particle board is by first manufacturing the thermosetting laminate of a number of paper layers impregnated with melamine formaldehyde resin and then to glue this thermosetting laminate onto a core for example fibre board or particle board. It is

also known to feed a few melamine formaldehyde impregnated paper webs together with sheets of particle or fibre board through a continuous laminate press.
SUMMARY
The present disclosure provides a laminate board comprising Phenol Formaldehyde (PF) coated core board; at least one Barrier layer impregnated with Melamine Formaldehyde (MF) resin or Urea Formaldehyde (UF) resin placed on either side of the core board; at least one Abrasion resistant layers impregnated with MF resin or UF resin placed on either side of the Barrier layer. The three layers are inter-linked to each other for good bonding and developing resistance to factors such as swelling in water/ water absorption, rupture, abrasion, steam, crack, cigarette burn and stain. The thickness of the PF coated core board is 0.10mm, the thickness of the barrier layer impregnated with MF resin or UF resin is 0.10mm, and the thickness of the abrasion resistant layer impregnated with M.F Resin or UF resin is 0.15mm.
The present disclosure provides a laminate board that has accurate matching. The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a rush of impregnation with PF resin and MF resin or UF resin. Therefore, the present disclosure provides solution to the problems of deviation in different layers when the layers are subjected to lamination leading to distorted laminate boards.
The present disclosure provides a laminate board using cement bonded particle board technique. The present disclosure provides a process of preparation of said laminate board comprising sanding said core board, filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin; placing at least one barrier layer above said core board and at

least one barrier layer below said core board, wherein said barrier layer is impregnated with a meiamine formaldehyde resin or a urea formaldehyde resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a meiamine formaldehyde resin or a urea formaldehyde resin; assembling said core board, said barrier layers and said abrasion resistant layers to obtain a book system; subjecting said book system to a suitable specific pressure and suitable temperate for suitable time followed by cooling and trimming undesired edges of said book system to obtain said laminate board.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
Figure 1; Layer assembly of the laminate board
DETAILED DESCRIPTION
The laminate board of the present disclosure has (1) PF coated core board; (2) at least one Barrier layer impregnated with MF resin or UF resin placed on either side of the core board; (3) at least one Abrasion resistant layers impregnated with MF resin or UF resin placed on either side of the Barrier layer as provided in Figure 1. The three layers are inter-linked to each other for good bonding and developing resistance to factors such as swelling in water/ water absorption, rupture, abrasion, steam, crack, cigarette bum and stain. The thickness of the P.F coated core board is 0.10mm, the thickness of the barrier layer impregnated with M.F resin or UF resin is 0.10mm, and the thickness of the abrasion resistant layer impregnated with M.F Resin or UF resin is 0.15mm. The present disclosure provides that the core board is laminated with decorative paper of minimum gram per square meter (gsm).
The term "thermosetting" refers to compounds that soften when initially heated, but hardens permanently once it has cooled. Thermosetting materials are made of long-chain polymers that cross-link with each other after they have been heated,

rendering the substance permanently hard. In the present disclosure, PF, MF and UF are the thermosetting resins used.
The present disclosure further relates to a composition of the resin that is applied to the surface of the core board. The core board such as cement bonded wooden particle board is subjected to periodic heating and cooling. The present disclosure provides a laminated cement bonded wooden particle board which has highly decorative having good texture, gloss and smooth finish.
The terms "plain board", and "core board" are used interchangeably in the present disclosure. The "plain board" or "core board" is used as a starting material for preparing the laminate. The "plain board" and "core board" includes but is not limited to saw board, fiber board, particle board, cement bonded fiber board and cement bonded wooden particle board.
The term Phenol Formaldehyde resin is also referred to as PF resin in the present disclosure.
The term Melamine Formaldehyde resin is also referred to as MF resin in the present disclosure.
The term Urea Formaldehyde resin is also referred to as UF resin in the present disclosure.
The terms "base paper", "decor paper" and decor sheet" are used interchangeably herein after.
The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation.
The term "abrasion resistant layer" refers to decor sheets impregnated with MF resin or UF resin as this layer provides abrasion resistance to the laminate board of the present disclosure.

The term "barrier layer" refers to sheets, preferably one or more Kraft sheets impregnated with MF resin or UF resin.
The terms "Phenol resin" and "Phenol formaldehyde resin" are used interchangeably herein after.
IS 2380: Part 1 to 23 refers to Indian Standards for methods of test for wood particle boards and boards from other lignocellulosic materials.
I.S 14276 refers to Indian Standard for Cement Bonded Wood Particle Board specification (Plain).
IS 12823 refers to Indian Standard for "Wood Products - Prelaminated Particle Boards - Specification"
In the present disclosure, the singular forms "a", "an", and "the" include plural reference, unless the context clearly dictates otherwise. Thus, for example, a reference to "sheet" includes a plurality of sheets, a reference to "layer" also includes a plurality of layers and a reference to "paper" is also a reference to one or more papers thereof known to those skilled in the art. Similar syntactic principal also applies to other components of the disclosure such as board.
In an embodiment the present disclosure provides a laminate board that is resistant to water absorption, rupture, abrasion, steam, cracks, cigarette bums and stains, said laminate board comprising; a core board impregnated with a phenol formaldehyde resin; at least two barrier layers, wherein at least one barrier layer is positioned above said core board and at least one barrier layer positioned below said core board, wherein each of said barrier layers are impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and at least two abrasion resistant layer, wherein at least one abrasion resistant layer is positioned over outer surface of said barrier layers, wherein each of said abrasion resistant layers is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin.

In another embodiment the present disclosure provides a laminate board that has density not less than 1250 kg/m^
In further another embodiment the present disclosure provides a laminate board that has moisture content in the range of 6 to 12 percent by weight of the board.
In another embodiment the present disclosure provides a process of preparation said laminate board, said method comprising; sanding said core board, optionally filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin; placing at least one barrier layer above said core board and at least one barrier layer below said core board, wherein said barrier layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; assembling said core board, said barrier layers and said abrasion resistant layers to obtain a book system; subjecting said book system to a suitable specific pressure and suitable temperate for suitable time followed by cooling and trimming undesired edges of said book system to obtain said laminate board as shown in Figure 1.
In yet another embodiment the present disclosure provides process of preparation said laminate board, wherein the core board includes but is not limited to saw board, fiber board, particle board, cement bonded particle board or cement bonded fiber board. The dents in the core boards irrespective of the type of board are filled with cement paste. The process involves use of novel cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure.
In The process involves use of cement bonded particle board (CBPB) process for obtaining laminate boards of the present disclosure.

In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said sanding is carried out at air pressure in the range of 2 to 5 kg/cm^.
In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable specific pressure is in the range of 30-40 Kg/cm^
In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable temperate is in the range of I25°C-140°C.
In another embodiment the present disclosure provides a process of preparation said laminate board, wherein said suitable time is in the range of 20-25 min.
In an embodiment of the present disclosure the laminate board has PF coated core board; at least one Barrier layer impregnated with MF resin or UF resin placed on either side of the core board; at least one Abrasion resistant layer impregnated with MF resin or UF resin placed on either side of the Barrier layer.
In an embodiment of the present disclosure the Barrier layer is impregnated with MF resin.
In another embodiment of the present disclosure the Barrier layer is impregnated with UF resin.
In yet another embodiment of the present disclosure the Abrasion resistant layer is impregnated with MF resin.
In yet another embodiment of the present disclosure the Abrasion resistant layer is impregnated with UF resin.
In an embodiment of the present disclosure, there are more than one barrier layer placed on either side of the core board.

In another embodiment of the present disclosure, there is one barrier layer placed on either side of the core board.
In still another embodiment of the present disclosure, there are more than one abrasion resistant layers placed over the barrier layer.
In still another embodiment of the present disclosure, there is one abrasion resistant layer placed over the barrier layer.
In an embodiment of the present disclosure, the barrier layer comprises of Kraft sheets impregnated with Melamine formaldehyde (MF) resin.
In another embodiment of the present disclosure, the barrier layer comprises of Kraft sheets impregnated with Urea formaldehyde (UF) resin.
In an embodiment of the present disclosure, the abrasion resistant layer comprises of decor sheets impregnated with Melamine formaldehyde (MF) resin.
In an embodiment of the present disclosure, the abrasion resistant layer comprises of decor sheets impregnated with Urea formaldehyde (UF) resin.
In an embodiment of the present disclosure, the laminate board can be used for several applications such as constructing floors, floor headings, table tops, work tops, wall panels, doors, windows, work stations and partitions.
The present disclosure provides preparation of laminate board wherein core (plain) boards were selected based on the desired finished laminate board thickness to be prepared. The core boards were sanded in sanding machine with 60 & 100 Grit sanding beU to obtain finished surface and uniform thickness. After sanding, the sanded boards were inspected and defect free sanded boards were collected. If necessary, dents on the sanded board surface was filled with cement by adding slight water. Phenol formaldehyde (PF) Resin is applied on the both sides of the sanded board. Tissue/Barrier and decor paper impregnated in MF resin are placed over the PF resin coated sanded board and assembled into a

book system. The assembled boards (book system) as a lot were fed into a multi day light press and specific pressure of 30 to 40 Kg/Cm^ was applied wherein a temperate was maintained at about I25°C to 140°C for 20 to 25 minutes cycle time. The boards (book system) were cooled to the temperature about 40° C. After cooling, boards (book system) were removed from the press. The assembled boards (book system) were separated from the lot and excess paper edges of each of the assembled boards were trimmed to obtain the laminated board. The layer assembly of the laminate is shown in Figure 1.
In an embodiment of the present disclosure, the PF resin is used as binding agent that helps in binding the other layers placed on either sides of the board. The other layers include the barrier layer positioned above and below said plain board coated with PF resin.
In another embodiment of the present disclosure, the barrier layer comprises of one or more Kraft sheets impregnated with a thermosetting resin.
Another embodiment of the present disclosure provides that the thermosetting resin is Melamine formaldehyde (MF) resin.
Yet another embodiment of the present disclosure provides that the thermosetting resin is Urea formaldehyde (UF) resin.
In another embodiment of the present disclosure, the barrier layer impregnated with MF resin serves as water absorption resistant layer.
In another embodiment of the present disclosure, the decor sheets impregnated with thermosetting resin is abrasion resistance. The decor sheets impregnated with thermosetting resin is also referred to as the abrasion resistant layer.
In an embodiment, the present disclosure provides laminate board comprising core board ranging from 10 to 13Kgs, Base Paper coated with thermosetting resin as exemplified ranging from 0.150 to 0.200kg, P.F resin ranging from 0.150 to

0.200 Kgs and M.F resin or UF resin or combination thereof ranging from 0.750 to 1.000 kg.
In another embodiment, the present disclosure provides that the base papers refer to barrier layer and abrasion resistant layer.
In another embodiment of the present disclosure, the laminate board has accurate matching. The term accurate matching refers to alignment of different layers of the laminate as mentioned above without any deviation. The laminate board of the present disclosure surprisingly has accurate matching due to the compatibility between the different layers of the laminate board that is a result of impregnation with PF resin and MF resin or UF resin.
In another embodiment of the present disclosure, the sanding is done using belts having dimension in the range of 50 to 120 grits.
In another embodiment of the present disclosure, the barrier layer comprises of Kraft sheet impregnated with MF resin or UF resin and the abrasion resistant layer comprises of decor sheet impregnated with MF resin or UF resin.
In still another embodiment of the present disclosure, the laminate board has accurate matching due to compatibility between the PF resin coated plain board and MF resin or UF resin impregnated other layers, namely the barrier layer and the abrasion resistant layer.
In yet another embodiment of the present disclosure, felt cloth and graphite pad are used in sanding of the core board before impregnating the PF resin on the core board.
In another embodiment of the present disclosure the laminate boards are resistant to steam as per IS: 12823 and exhibits only slight change in color after exposing the laminate board to steam for a long duration, after about 2 hrs.

In an embodiment of the present disclosure the laminate boards are crack resistant. The laminate boards when subjected to high stress show crack after 24 hours duration on the surface.
In another embodiment of the present disclosure the laminate boards are abrasion resistant as per IS2380.
In yet another embodiment of the present disclosure the laminate boards have pH in range from 11 to 13.
In still another embodiment of the present disclosure the laminate boards have modulus of elasticity of the laminate board not less than 3000 N/mm^ complying with IS: 14276.
In another embodiment of the present disclosure the laminate boards have screw withdrawal strength at face was not less than 1250 N and at edges was not less than 850 N.
In an embodiment of the present disclosure the laminate boards have tensile strength PPler to surface not less than 0.2 N/mm^ complying with IS: 14276.
The tensile strength PPler to surface after ageing test of the laminate board was not less than 0.2 N/mm^ complying with IS: 14276.
In still another embodiment of the present disclosure the laminate boards have modulus of rupture not less than 11 N/mm^ complying with IS: 14276.
In yet another embodiment of the present disclosure the laminate boards have water absorption resistance or swelling in thickness of maximum 5% after 2 hrs complying with IS: 14276. The water absorption by the laminate boards is not to exceed the prescribed limits as per IS: 14276, Maximum 7% after 2 Hrs, and Maximum 15% after 24 Hrs immersion in water.

In further another embodiment of the present disclosure the laminate boards exhibit average moisture content in the range of 6 to 12 percent by weight of the laminate complying with IS: 14276.
In further another embodiment of the present disclosure the laminate boards have
* density of not less than 1250 Kg/m^ The laminate boards obtained from the
above mentioned process can have density variation that is permissible to meet
IS2380 requirements.
While various embodiments and/or individual features of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. As will be also be apparent to the skilled practitioner, all combinations of the embodiments and features taught in the foregoing disclosure are possible and can resuh in preferred executions of the present disclosure.
EXAMPLES
The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and the description to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention nor are they intended to represent that the experiments below are all and only experiments performed.
EXAMPLE 1
PREPARATION OF LAMINATE BOARD 1. Preparation of pre-laminate board A. Selection of core/plain boards
The plain board which herein is exemplified by cement bonded pre-laminated particle board was selected at random. The selected boards were tested as specified in I.S 2380 for requirements such as length, width, thickness, edge

straightness and squareness. I.S 2380 refers to standard methods of test for Wood Particle Boards and Boards from other lignocellulosic materials.
The plain board must be 1.0 to 2.0 mm thickness more than the desired laminate board. That means the sanding allowance must be given 1.0 to 2.0mm to get the uniform surface without any unsanding patches. After selecting the proper boards for sanding, the boards were kept in a lot form (not more than one Clamp at a time i.e. 960mm ht) and placed on the stacking table.
B. Sanding
Two different operations were employed for sanding, namely,
1) Rough operation with 50/60 Grit Sanding belts of size 1350mm X 2800mm.
2) Fine operation with 100/120 Grit Sanding belts of size 1350mmX 2800mm.
For sanding, the sanding machine was made ready. Sanding operation is dependent on the thickness of the plain board. The thickness of the saw boards was observed and the machine was adjusted accordingly to cut maximum 0.5mm and cut on each motor (top and bottom). The load was observed while the sanding operation was going on and the speed of the conveyor was adjusted such that that it did not take the load of more than 150 Amps. The boards thickness was checked at different points (longitudinal & cross sectional). The variation of thickness should not be ± 0.1 of standard thickness. The standard thickness of the plain board for rough operation was 0.2mm more than the final lamination board. The dust suction of the sanding checked properly and thorough air cleaning is required at proper intervals to get more life of the bolts and to avoid the breakdowns of the machine.
Sanding operation
First operation The sanding machine was thoroughly cleaned. The belts were checked for damages and mounted into the machine by properly observing the

direction of the behs. For rough operation 50 or 60 Grit belts were used. The air pressure was checked properly. The top and bottom air pressures were adjusted to not less than 4.5 Kgs/Cm^ and 2.0 Kgs/Cm^ respectively. The top and bottom oscillations were checked properly before starting the machine. The first motor was started with on-off by observing the oscillation. If the oscillation was proper, the operation was continued to take full speed. The same step can be repeated for the second motor. Therefore, the above steps ensured that the sanding machine was ready for operation.
Second operation: Preparation of Graphite Pads The frame to be inserted in the machine was thoroughly cleaned and the suitable felt cloth (4 to 8mm) was mounted into the frame with suitable adhesive. Graphite paper was attached on the felt cloth with suitable adhesive and the frame was allowed to stand for some time for proper setting. The frame with this attachment was properly put into the machine in the grove. 100/120 Grit belts were mounted in the drums and the graphite pads must be inside the belts. The remaining operation was continued like the first operation and the cutting of the board with the sanding belt was not more than 0.1mm at each motor. The ampere range was maintained by adjusting the speed of the machine such that ampere range was not more than 100 Amps. The thickness of the board was observed and the standard/required thickness for lamination with in the levels of less than 0.1 to 0.2 mm variation within the board was maintained.
C. Inspection and Segregation of the sanded boards
For selection of sanded board for preparing lamination board, each board was inspected for physical verification. The lab reports of the mechanical properties of the laminate board were studied. The following points were considered at the time of inspection: 1. The board were defect free (without any damages); 2. The boards were within the tolerance of length, width and thickness; 3. Surface was smooth without any defects; 4. No unsanded portion was accepted on either side

of the surface; 5. No Dents were accepted 6. Minor dents/holes were covered with cement filling. 7. No over size chips were allowed on the surface.
2. Preparation of Resins
Preparation of Phenol Formaldehyde (PF) Resin
The raw materials used for preparation of PF resin are: (a.) Phenol (Granules 100% Pure); (b.) Formalin (Colorless with 36-37%); and (c.) Methanol.
Batch Preparation: Phenol = 215 Kgs and Formalin =215 Kgs 1:1 Ratio
Methanol =185 Kgs Catalyst =10 Kgs
Formalin of 215 Kgs was charged in the Kettle Reactor and 215 Kgs of Phenol was added through vacuum suction and the mixture was stirred. Liquid ammonia was added for 10 Kgs to maintain the pH at 7.0. Steam heating was started to allow the temperature to go up to 75° C which was attained within 15 to 20 min. The steam heating was stopped and the exothermic reaction levels were allowed to advance further. The temperature of the above mixture was maintained at 100° C and the reaction was stopped. This reaction approximately continues for 3.0 hrs. The attainment of polymerization to requisite levels was confirmed by testing the set time and start time. Vacuum distillation was performed to remover the water quantity of 140 Kgs. The distillation was stopped followed by addition of 185 kgs of methanol after which cooling was started. The pH was adjusted and maintain at about 8.0. The liquid is in stringing form semi solid starts. To store it in drums, solvent was added to maintain the viscosity. Resin viscosity was maintained when it was checked with B4 Ford cup. The PF resin obtained from the above process had the following property: Viscosity 15 Sec with B-4 Ford cup, specific gravity-1.00 to 1.07, Geltime at 150°C - 90 to 100 Sec, pH 7.0 to 8.0.
Preparation of Melamine Formaldehyde (MF) Resin

Formalin = 150Kgs. NaOH:NBA = 5 Kgs.
Melamine = 125 Kgs. MEG : 12 Kgs.
Formalin was charged in the reactor and then melamine was added with continuous stirring. The ratio of melamine to formalin was maintained as 1:2.2. The pH was adjusted to 8.5 to 9.0 by the addition of 10% caustic solution. By continuous stirring heating was started. The temperature was maintained at 95° C by steam heating. The polymerization reaction was advanced further. The heating was continued till the required polymerization level was attained. A precipitation test water tolerance was measured when the ratio of 1:8 is obtained. The heating is stop and cooling started. All additives like Urea, MFG, NBA, modifier as mentioned above were added and the PH was maintained at around 9.0. The mixture was continued till the resin attained temperature of about 40° C. The final yield of the MF resin was 304 kg.
Similarly, Urea Formaldehyde (UF) resin can be prepared and by using the conventional processes.
3. Preparation of Laminate board
The inspected sanded boards obtained by the above mentioned process were selected as per requirement. The surface of the sanded boards was observed and the dents if any on the surface were covered with semisolid cement. The phenol resin (180 gm - 200 gm) was coated uniformly on both the surface of the sanded board with the help of spray gun and allowed it to rest in the stand for air drying.
Impregnation
Impregnation is the process of deposition of MF Resin on the base paper in dry condition. The base paper in the present disclosure is exemplified by Kraft paper and decor paper.
The decorative paper required for lamination was loaded on a metal stand in front of the resin tray. The paper was arranged such that it passed through the ok

rollers and into the turf and lead to parallel rod which passed through hot air zone. MF resin was loaded into the tray and the above decor paper was passed through the resin and the squeezing rollers. The speed of the machine was adjusted such that the base paper was allowed to absorb the required quantity of resin and the squeezing rollers were adjusted such that to squeezed the excess quantity of resin. MF resin absorbed paper was made to travel in the hot air dryer and cooling rollers. The MF resin absorbed paper was cut to the required sizes through the cutter. The paper was made to travel in the hot air zone I & II at temperature of 135° C to 140° C by floating media without touching to any sides. The speed of the machine was adjusted to maintain the volatile content of the paper at 6.0 to 7.0. The stack of the treated papers, namely, decor layer impregnated with MF resin was stored in A.C room. The decor layer impregnated with MF resin is referred to as abrasive resistant layer.
Similarly, barrier layer was prepared by impregnating one or more kraft sheets with MF resin by the process mentioned above.
Assembling of Book System in forming station
A Book system was assembled on a carrier plate in the forming station. The Book system contains 6 layers of padding paper (200 gsm), S.S plate of mat mould followed by MF coated Decorative paper, MF coated Tissue paper, PF coated Board and MF coated tissue paper and coated Decorative paper or coated back up white paper, S.S.Mould and Padding paper. Finally place a balancing 3mm S.S plate over the padding paper. The total formed book system was taken into loader. The same process was continued for eight day lights. The eight day book system which was ready in loader was pushed into Hydraulic press for further processing.
Hydraulic Press
Hydraulic press having eight day lights was thoroughly cleaned with air before taking the book system into press. The temperature was raised to 100° C by steam

heating maintained the pressure of steam at 2.0 to 2.5 Kg. The book system was taken into the press. The press was closed and hydraulic pressure was maintained at 105 Kg/CM^ to 115 Kg/CM^ which is app. equivalent to 30 Kg/cm^ (specific pressure). Heating was needed to raise the temperature to 125°C ± 2°C. Heating cycle was continued for 20 min for curing of impregnated material (I.M) such as barrier and decor layers. The heating and cooling cycle was started for 15 min. When the plates reached 40°- 45°C, the press was opened. All the light book systems were taken into un-loader. One by one book system was taken into forming station and the boards were deputed from the moulds. The boards are stacked properly. The edges of the book system was cleaned and inspected for physical defects on the surface. The laminate boards so obtained were properly packed by pasting stickers and kept ready for dispatch.
EXAMPLE 2
Properties of the laminate board
From the laminate board obtained above, portions of 150mm were cut from the edges. The processed laminate boards were tested as per conditions specified in l.S 2380. l.S 2380 refers to standard methods of test for wood particle boards and boards from other lignocellulosic materials. l.S 14276 refers to Cement Bonded Wood Particle Board specification (Plain). The laminate board obtained was tested to determine the density, moisture content, water absorption property, swelling in water, modulus of rupture, tensile strength PPler to surface, tensile strength PPler to the surface after ageing test, screw withdrawal strength, modulus of elasticity and pH value.
Density of laminate boards
There were three laminate boards of dimension 75mm wide and 150mm long in full thickness taken as test samples. The density of the boards determined for each test specimen was not less than 1250 Kg/m\ The laminate boards obtained

from the above mentioned process can have density variation that is permissible to meet 1S2380 requirements
Moisture content of the laminate board
There were three laminate boards of dimension 75mm wide and 150mm long in full thickness taken as test samples. The laminate boards of all other possible dimensions are also a subject matter encompassed by the present disclosure. The laminate boards exhibited average moisture content in the range of 6 to 12 percent by weight of the laminate and complies with IS: 14276.
Water absorption property of the laminate board
There were three laminate boards of 300mm X 300mm dimension taken as test samples. The laminate boards of other dimensions are also a subject matter encompassed by the present disclosure. The water absorption was determined for each test specimen and the average value was not to exceed the prescribed limits as per IS: 14276, Maximum 7% after 2 Hrs, and Maximum 15% after 24 Hrs immersion in water.
Laminate boards water swelling property
There were three laminate boards of size 200mm X 100mm in full thickness taken as test samples. The swelling in thickness shall be determined for each test specimen for 2 hrs soaking in water and the average value shall not exceed the specified limits specified as per IS: 14276, maximum 5% after 2 hrs.
Modulus of rupture of the laminate board
There were three laminate boards of size 200mm X 100mm in full thickness taken as test samples. The modulus of rupture was determined for each test specimen and the average value was not less than 11 N/mm^ complying with IS: 14276.
Tensile strength PPler to surface of the laminate board

There were three laminate boards of size 50mm X 50mm in full thickness taken as test samples. The tensile strength perpendicular to surface was determined for each test specimen and the average value was not less than 0.3 N/mm^ complying with IS: 14276.
Tensile strength PPIer to the surface after ageing test of the laminate board
There were three laminate boards of size 50mm X 50mm in full thickness taken as test samples. The tensile strength PPler to surface was determined for test specimen after subjecting the test specimens in accordance with the method prescribed in I.S 2380. The test specimens were immersed in water at 27 ± 2° C and water is brought to boiling and kept at boiling temperature for two hours. The test specimens were then cooled in water to 27 ± 2° C and tested for tensile strength PPler to the surface. The tensile strength PPler to surface was determined for each test specimen and the average value was not less than 0.2 N/mm^ complying with IS: 14276.
Screw withdrawal strength of the laminate board
There were three laminate boards of size 150mm X 75mm in full thickness taken as test samples. The screw withdrawal strength of the laminate board was in concordance with IS: 14276. The screw withdrawal strength was determined for each test specimen and the average value at face was not less than 1250 N and at edges was not less than 850 N.
Modulus of Elasticity of the laminate board
There were three laminate boards of size 50mm X 50 mm in full thickness taken as test samples. The three test specimens exhibited modulus of elasticity conforming to the requirement specified in I.S 2380. The modulus of elasticity of the laminate board was determined for each test specimen and the average value was not less than 3000 N/mm^ complying with IS: 14276.
pH value of the laminate board

There were three laminate boards of size 150mm X 75mm in full thickness taken as test samples. The laminate boards of other dimensions are also encompassed by the present disclosure. The pH of the laminate boards was found to range from 11 to 13.
Abrasion Resistance of the laminate boards
The abrasion resistance of the laminate boards was determined by IS2380and was found to be 450 Revolutions complying with IS: 12823.
Steam resistance of the laminate boards
The resistance of the laminate boards to steam was determined for each test specimen in accordance with the method prescribed by IS2380. There were laminate boards of size 100mm X 100mm taken as test samples. The laminate boards were place on conical flask filled with water up to 100 C.C on the hot plate. The mouth of the conical flask was covered with the specimen such that the surface of the laminate board to be tested faced the conical flask. A clamp was used to secure laminate board from falling down. The water in the conical flask was heated using an electric heater. The water was heated for a period of 2 hours after the water start boiling. The steam cones contact the board surface and escape into atmosphere. The surface of the laminate board facing the conical flask was observed. The laminate boards did not show any sign of blaster. The laminate boards were tested for determination of change in surface finish. There laminate boards exhibited slight change in color after a long duration, after about 2 hrs as per IS: 12823.
Crack resistance of the laminate boards
Crack resistance of the laminate board was determined for each test specimen. The test specimen of size 100mm X 100mm was subjected to a temperature of 70 ± 2° C. The specimens after 24 hours duration were observed for cracks on the

lamination surface of the boards. The laminate boards did not exhibit any sign of cracks or de-lamination as per IS: 12823.
Cigarette resistance of the laminate boards
Resistance to cigarette burn was determined by placing a slowing cigarette horizontally on the laminate boards of size 200mm X 200mm for 60 seconds. The area where the cigarette was contacted with the laminate board was cleaned with water or a suitable solvent. The color change in the cigarette contacted area was observed. The laminate boards did not leave any mark or stain on the specimen after cleaning with water or solvent complying with IS: 12823.
Stain resistance of the laminate boards
Resistance to stain was determined for the laminate boards. The stains on the laminate board were easily removed by cleaning with water, solvent or detergent thereby complying with IS: 12823.

claim
1. A laminate board that is resistant to water absorption, rupture, abrasion,
steam, cracks, cigarette burns and stains, said laminate board comprising
a core board impregnated within a phenol formaldehyde resin;
at least two barrier layers, wherein at least one barrier layer is positioned above said core board and at least one barrier layer positioned below said core board, wherein each of said barrier layers are impregnated with a melamine formaldehyde resin or a urea formaldehyde resin; and
at least two abrasion resistant layer, wherein at least one abrasion resistant layer is positioned over outer surface of said barrier layers, wherein each of said abrasion resistant layers is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin.
2. The laminate board as claimed in claim 1, where said laminate board has density not less than 1250 Kg/m3. The laminate board as claimed in claim 1, where said laminate board has moisture content in the range of 6 to 12 percent by weight of the board.
4. The laminate board as claimed in claim 1, wherein said core board is selected from a group comprising saw board, fiber board, particle board, cement bonded particle board and cement bonded fiber board.
5. A process of preparation said laminate board of claim 1, said method comprising;
sanding said core board, filling dents if any of the core board with cement paste and coating the core board with a phenol-formaldehyde resin;
placing at least one barrier layer above said core board and at least one

barrier layer below said core board, wherein said barrier layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde . resin; and placing at least one abrasion resistant layer over outer surface of said barrier layers, wherein said abrasion resistant layer is impregnated with a melamine formaldehyde resin or a urea formaldehyde resin;
assembling said core board, said barrier layers and said abrasion resistant layers;
subjecting the above assembly to a suitable specific pressure and suitable temperate for suitable time followed by cooling and optionally trimming undesired edges to obtain said laminate board.
6. The process as claimed in claim 5, wherein said sanding is carried out at
air pressure in the range of 2 to 5 kg/cm'‘.
7. The process as claimed in claim 5, wherein said suitable specific pressure
is in the range of 30-40 Kg/cm’.
8. The process as claimed in claim 5, wherein said suitable temperate is in
the range of 125°C-140°C.
9. The process as claimed in claim 5, wherein said suitable time is in the
range of 20-25 min.

Documents:

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Patent Number

259490

Indian Patent Application Number

168/CHE/2007

PG Journal Number

12/2014

Publication Date

21-Mar-2014

Grant Date

14-Mar-2014

Date of Filing

25-Jan-2007

Name of Patentee

NCL INDUSTRIES LTD

Applicant Address

H. O RAGHAVA RATNA TOWERS, 7TH FLOOR, ABIDS, HYDERABAD - 500001

Inventors:

#	Inventor's Name	Inventor's Address
1	S.S. RAJU	H. O RAGHAVA RATNA TOWERS, 7TH FLOOR, ABIDS, HYDERABAD - 500001
2	K.RAVI	H. O RAGHAVA RATNA TOWERS, 7TH FLOOR, ABIDS, HYDERABAD - 500001

PCT International Classification Number

B28B1/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA