JPS581671B2 - Decorative board manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to (1) a method for producing a decorative board that can be cut or bent.

Decorative laminates using thermosetting resins made of diallyl phthalate monomers and/or prepolymers and unsaturated polyesters have been well known.

These were manufactured by dissolving resin in a solvent and impregnating or coating it on ordinary patterned paper, overlapping this with a base material and using a hot pressure molding method.

This method uses a heat press to laminate the impregnated paper and the base material, so the resin penetrates the entire paper, and the resulting decorative laminate has excellent performance, but the surface decorative layer is flexible. Due to its poor properties, the processing methods used to further process it into various boxes and furniture have been severely limited.

For example, when treating the corners of cabinets, that is, the joints and wood edges between the top and side panels, or the wood edges and wood ends of shelves,
Conventionally, it was possible to make a so-called U-cut with a large radius, but it was not possible to make a V-cut with a more acute angle.

At present, decorative boards using soft polyvinyl chloride are available.
It is considered to be the only practical material that can be cut.

However, polyvinyl chloride has poor heat resistance and solvent resistance, and generates harmful gases when burned, so it is not suitable for use in electrical appliances, kitchen appliance cabinets, cosmetics, furniture, and the like.

On the other hand, printed plywood, which is made by applying a small amount of amino alkyd resin to thin paper and curing it, is laminated to plywood of about 2.5 mm thickness.The surface of printed plywood can be produced endlessly, and the amount of resin applied is small, making it economical. It is produced in large quantities because it is inexpensive.

However, this printed plywood usually has a surface layer of thin paper with a basis weight of about 23 g/m2 and a resin coating amount of 15 g.
/ m2, and as a result, the design quality, which is the original purpose of decorative plywood, is inferior, and it is also inferior in water resistance, heat resistance, hardness, and abrasion resistance, and cannot withstand advanced workability. It is.

Furthermore, this decorative hardened paper had a defect in that the concealing power of the base was low, and the unevenness of the base appeared as it was, resulting in a so-called thinning of the eyes, lowering the cosmetic properties, and giving the paper the image of a low-quality product.

In view of the above drawbacks, the present inventors manufactured printed plywood with a flexible surface layer and excellent economic efficiency using diallyl phthalate resin, which has excellent performance such as design and heat resistance. As a result of various studies on methods to do this, we decided to use decorative hardened paper, which is made by applying and hardening a composition containing diallyl phthalate and air-curable unsaturated polyester to thin paper, as the surface layer, and to use soft polyvinyl chloride between the surface layer and the base material. Alternatively, the present inventors have discovered that a decorative board bonded together via a nonwoven fabric can be obtained without the above-mentioned drawbacks and meets the intended purpose.

That is, the present invention uses a cured paper in which a solvent-free resin composition containing diallyl phthalates and an air-curable unsaturated polyester is applied to thin paper in an amount of 90 to 170% by weight as a resin content and then cured as a surface layer. (2) A method for producing a decorative board that can be cut or bent, which is characterized in that it is attached to a base material using an adhesive through a soft polyvinyl chloride sheet or nonwoven fabric.

The thin paper used in the present invention has a basis weight of 15 to 3
A material with a weight of 5 g/m2 is suitable, and may be printed or untreated.

Further, the thin paper may be subjected to a treatment such as applying a urethane resin or the like to adjust the permeability of the resin or to increase the strength between the sheets.

Thin paper having a basis weight of less than 15 g/m2 is undesirable because the strength of the paper is low, resulting in poor workability and poor hiding power.

If the amount exceeds 35 g/m2, the permeability of the resin into the paper increases, and therefore, with the amount of resin specified in the present invention, sufficient performance as a surface layer cannot be obtained and the flexibility is poor.

It is also disadvantageous in terms of economic efficiency of decorative paper.

The diallyl phthalates used in the present invention refer to diallyl orthophthalate, diallyl isophthalate, and diallyl terephthalate alone or as a mixture thereof.

The air-curable unsaturated polyester (hereinafter simply referred to as unsaturated polyester) is produced by using the following components and using a method commonly used in producing general unsaturated polyesters.

That is, (a) from 0.6 to 0.8 mol of α,β-unsaturated dibasic acid or its acid anhydride and 0.4 to 0.2 mol of aliphatic cyclic unsaturated dibasic acid or its acid anhydride. and an alcohol component having an ether bond such as diethylene glycol or triethylene glycol at a ratio of 0.0% alcohol component to 1 mole of acid component. (b) 0.3 to 0.8 mol of an α,β-unsaturated dibasic acid or its acid anhydride and a saturated An acid component consisting of 0.2 to 0.7 moles of a basic acid or its acid anhydride, an aliphatic polyhydric alcohol such as ethylene glycol, diethylene glycol, and propylene glycol, and allyl glycidyl ether or trimethylol propane diallyl ether,
Allyl ethers of polyhydric alcohols such as glycerin monoallyl ether and glycerin diallyl ether, and 0.01 aliphatic polyhydric alcohol per mole of acid component.
Heating in an inert gas at a ratio of ~0.2 mol and 0.8 to 1.1 mol of allyl ethers of polyhydric alcohols such as allyl glycidyl ether or trimethylolpropane diallyl ether, glycerin monoallyl ether, and glycerin diallyl ether. Refers to what is obtained by condensation.

These unsaturated polyesters (a) and (b) may be used alone or as a mixture in any proportion.

Examples of the α,β-unsaturated dibasic acid or its acid anhydride in the unsaturated polyester (a) include maleic acid, fumaric acid, itaconic acid, citraconic acid, etc., or acid anhydrides thereof. .

Aliphatic cyclic unsaturated dibasic acids or their acid anhydrides include tetrahydrophthalic acid, 3,6-endomethylenetetrahydrophthalic acid, methyl-3,6-endomethylenetetrahydrophthalic acid, and acid anhydrides thereof. .

In addition to the above-mentioned alcohols having an ether bond, there are dipropylene glycol, polyethylene glycol, and the like.

In addition, (b) α,β-unsaturated dibasic acids or their acid anhydrides in the unsaturated polyester include maleic acid, fumaric acid, itaconic acid, citraconic acid, etc., and acid anhydrides thereof; Examples of the acid or its acid anhydride include phthalic acid, phthalic anhydride, succinic acid, succinic anhydride, isophthalic acid, and adipic acid.

In addition to the above, examples of aliphatic polyhydric alcohols include dipropylene glycol, 1,3-butanediol, neopentyl glycol, and hydrogenated bisphenol A.

The ratio of diallyl phthalate and unsaturated polyester in the resin composition of the present invention is 20 to 60% by weight, preferably 3% by weight of diallyl phthalate based on the total amount thereof.
5 to 50% by weight is suitable.

If the amount of diallyl phthalate is less than this range, the desired physical properties of the cured paper cannot be obtained, and if it is too much, the time required for curing becomes longer and it is difficult to prevent wrinkles in the cured paper due to resin shrinkage. Can not.

In addition, the curing time can be adjusted and the decorative surface has a particularly high degree of heat resistance.
When weather resistance, solvent resistance, and abrasion resistance are required, an appropriate amount of diallyl phthalate prepolymer may be added.

At this time, a diallyl phthalate polymer solution containing 10 to 50% by weight of diallyl phthalate polymer can be used instead of diallyl phthalate.

The resin composition of the present invention contains 0.1 to 10% by weight of a curing catalyst.
Added.

Examples of the curing catalyst include organic peroxides such as penzoyl peroxide, methyl ethyl ketone peroxide, and lauroyl peroxide, and nitriles capable of generating radicals such as azobisisobutyronitrile.

Further, a curing accelerator can be added if necessary.

Such curing accelerators include organic metal salts such as cobalt naphthenate and cobalt octenoate, aliphatic amines, aromatic amines, and mercaptans.

The resin composition of the present invention may further contain additives commonly used in the technical field, such as anti-shrinkage agents, leveling agents, internal lubricants, polymerization inhibitors, and thickening agents.

The soft polyvinyl chloride sheet used in the present invention preferably has a thickness of 0.01 to 0.15 mm, and is particularly suitable for use as a decorative board for cutting or bending with a small radius.
Preferably, the diameter is 8 to 0.12 mm.

In addition, non-woven fabrics may be used without any particular restrictions as long as they are made by adding a binder to fibers such as rayon, vinylon, polypropylene, polyester, corderan, or synthetic pulp.
~20 g/m2 is preferred.

In general, thin paper itself lacks strength, so if a large amount of resin as in the present invention is applied and cured by a conventional method, numerous wrinkles of various sizes will occur, making it impossible to use it as surface decorative paper.

In order to eliminate the occurrence of such wrinkles, the present inventors proposed a method of applying tension to thin paper during the heat curing process to produce cured paper with no wrinkles, in a patent application filed on the same day. A decorative hardened paper obtained by a similar method is used as the surface layer.

That is, a solvent-free resin composition containing diallyl phthalates and an air-curable unsaturated polyester is applied to thin paper using a comma coater, a reverse roll coater, etc. so that the resin content is 90 to 170% by weight. , when curing, use methods such as hot air, infrared lamps, and ultraviolet irradiation.
Heating to 0-150℃, total curing time 7 from the start of heating.
5-15k per meter width for tissue paper up to 0%
g, preferably 7 to 10 kg, and the remaining 30 kg.
%, it is possible to obtain a cured paper completely free of wrinkles by curing it under substantially no tension.

If the amount of resin applied to the thin paper is less than 90% by weight, satisfactory performance in terms of physical properties cannot be obtained due to insufficient resin.

Moreover, if it exceeds 170% by weight, the balance between shrinkage and hardening between the thin paper and the resin cannot be maintained, and the occurrence of wrinkles and cracks cannot be prevented.

The cured paper thus obtained has excellent physical properties such as design, heat resistance, weather resistance, and abrasion resistance, as well as flexibility.

A decorative board with a flexible surface layer can be obtained by bonding this to various base materials, such as various types of plywood, particle board, aluminum plate, iron plate, etc. using an appropriate adhesive. When using a base material that is as thick as 20 mm or heavy, this may cause damage to ■ If an abnormal load is applied between the V-cutting process and the bending process when cutting and bending, ■ Cured paper may break.

If such breakage occurs frequently, the work efficiency will be significantly reduced, making it unsuitable as a material for products.

In order to prevent such breakage of the cured paper, it is effective to interpose a reinforcing material between the base material and the cured paper, and in the present invention, a soft polyvinyl chloride sheet or a nonwoven fabric is used as such a reinforcing material. It is something.

In carrying out the present invention, adhesives such as vinyl acetate, vinyl acetate-urea, acrylic, or chloroprene may be used to bond the cured paper, soft polyvinyl chloride sheet or nonwoven fabric, and base material, such as roll press, etc. It is manufactured by bonding them together in a heated or non-heated state.

In this case, a method may be used in which only the cured paper and the soft polyvinyl chloride sheet or nonwoven fabric are first bonded together, and then this is bonded to the base material.

The decorative laminate thus obtained has a hard surface and does not cause any visual fading, and even when laminated to a thin plywood for printed plywood, a smooth decorative surface can be obtained without being affected by the base material at all.

It also has good workability during processing, and the surface layer and base material do not peel off even during high-speed cutting and drilling.

In addition, since the decorative surface layer has good flexibility, it can be bent directly when metal is used as the base material, and when plywood or particle board is used, it can be bent not only on the surface of the board but also on the edges and ends of the wood. It is also possible to bond them together continuously, so-called wood end wrapping.

Therefore, it eliminates the need to separately adhere ribbon-shaped decorative paper or decorative board to the wood edges and edges of shelf boards, and the joints between top and side panels of cabinets, and then chamfer them, as in the past. By simply pasting the hardened paper of the invention through a soft polyvinyl chloride sheet or non-woven fabric, it is possible to bend and adhere it to the end of the wood or the end of the wood.

In addition, the cutting process that was previously possible only for decorative laminates with soft polyvinyl chloride as the surface layer is also possible with the decorative laminate of the present invention, and in terms of performance, it is better than conventional decorative laminates using soft polyvinyl chloride. It has superior heat resistance, solvent resistance, hardness, and abrasion resistance, and does not generate toxic gas when burned.

The present invention will be explained below with reference to Examples.

In each example, parts indicate parts by weight.

Example 1 Air-curing unsaturated polyester ("Epolack NW-2")
001 (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), 40 parts of diallyl orthophthalate, 3 parts of white carbon, and 0.02 part of hydroquinone were mixed, and the well-kneaded composition was mixed with 1 part of penzoyl peroxide, 1 part of methyl ethyl ketone peroxide, 0.45 part of cobalt octenoate was added and mixed well to prepare a resin liquid for coating.

The above resin liquid was applied to a thin paper having a basis weight of 28 g/m2 with a wood grain pattern printed thereon using a roll coater so as to have a weight of 40 g/m2, and the paper was introduced as a long sheet into a heating furnace at a temperature of 105°C.

In this heating furnace, the rolls are installed in an arch shape at intervals of 50 cm with an angle difference of 5 degrees from the entrance of the heating furnace to 70% of the length.

9 per meter of width of the thin paper from the entrance of the heating furnace to the part corresponding to 70% of the length of the thin paper in the heating furnace.
．． A tension of 5 kg was applied.

The thin paper was passed through the heating oven for a time corresponding to the curing time at the heating oven temperature, ie, 4 minutes, and the cured paper with no wrinkles was wound up into a roll.

An ethylene-vinyl acetate adhesive was applied to the back side of the obtained cured paper, and a 0.12 mm thick soft polyvinyl chloride sheet was bonded thereto using a roll press to obtain a laminated cured paper.

The decorative surface of the laminated hardened paper was not immersed in chloroform, acetone, or benzene, and the pencil hardness was H.

Further, no cracks or cracks occurred even when bent 120 degrees.

Next, this laminated hardened paper was coated with the above adhesive to a thickness of 5 mm.
A decorative board was obtained by bonding the veneer plywood with a roll press.

This decorative board had excellent solvent resistance, abrasion resistance, and heat resistance, and could be easily cut at high speeds.

Furthermore, since the decorative board could be bent at right angles and made into U-cuts, it could be used to make cabinets, wooden boxes, furniture, etc.

Example 2 After thoroughly kneading 6.5 parts of the unsaturated polyester used in Example 1, 35 parts of diallyl isophthalate, 3 parts of white carbon, and 0.02 part of hydroquinone, 2 parts of benzoyl peroxide and 0.0 parts of cobalt octenoate were mixed. 45 parts were added and mixed to prepare a resin liquid for coating.

Using a roll coater, the above resin liquid was continuously applied to thin paper with a basis weight of 35 g/m2 printed with a wood grain pattern at a thickness of 35 g/m2, and the same heating as in Example 1 was carried out, in which the temperature was set at 100°C while the paper was being kept long. The sample was introduced into a furnace, tension was applied under the same conditions as in Example 1, and the sample was passed through the heating furnace for a residence time of 4 minutes.

The resulting cured paper had no wrinkles and a smooth surface.

This cured paper was coated with an ethylene-vinyl acetate adhesive on one side and immediately bonded to a soft polyvinyl chloride sheet having a thickness of 0.15 mm to obtain a laminated cured paper, which was then wound into a roll.

The decorative surface of the above-mentioned laminated hardened paper was not affected by solvents such as chloroform, tetrahydrofuran, and acetone, and there was no change in the decorative surface when immersed in ethyl alcohol or whiskey, but the soft polyvinyl chloride sheet on the back surface became white. did.

Even when boiling water was dropped on the cosmetic surface, it did not soften, and the pencil hardness of the cosmetic surface was H.

This laminated cured paper was attached to a 10 mm thick particle board using an ethylene-vinyl acetate adhesive using a press to obtain a decorative board.

This decorative board was cut into a standard shape using a high-speed cutting tool, and the bent portion was cut to produce a cabinet.

There were no cracks or cracks on the surface of the bent part, and the cut part was beautifully finished.

The surface of this cabinet will not deform or whiten even if hot water or whiskey is spilled on it, and the surface hardness is higher than that of conventional cabinets whose surface layer is made of soft polyvinyl chloride, so it is less likely to get scratched.

Example 3 After thoroughly kneading 55 parts of the unsaturated polyester used in Example 1, 45 parts of diallyl orthophthalate, 3 parts of white carbon, and 0.02 part of hydroquinone, 2 parts of penzoyl peroxide, 1 part of methyl ethyl ketone peroxide, and octene were mixed. 0.45 part of cobalt acid was added and mixed to prepare a resin liquid for coating.

Using a roll coater, the above resin liquid was continuously coated to 40 g/m2 on thin paper with a basis weight of 28 g/m2 printed with a wood grain pattern, and the same heating as in Example 1 was carried out, in which the temperature was set at 105°C while the paper was being kept long. The paper was cured in an oven under the same conditions as in Example 1 to obtain a cured paper with a smooth surface without wrinkles, which was wound into a roll.

The back side of the obtained cured paper was coated with an ethylene-vinyl acetate adhesive and a polyester nonwoven fabric having a thickness of 0.13 mm and a basis weight of 16 g/m2 was bonded using a roll press to obtain a laminated cured paper.

The decorative surface of the laminated hardened paper was not affected by solvents such as chloroform, acetone, and benzene, and the pencil hardness was H.

Further, even when bent 180 degrees, no cracks or cracks occurred.

This laminated cured paper was attached to a 5 mm thick veneer plywood using the above adhesive using a roll press to obtain a decorative board.

The obtained decorative board has excellent solvent resistance, abrasion resistance, and heat resistance.
It was able to withstand high-speed cutting.

In addition, it is possible to bend the decorative board at right angles (■-cut and U-cut processing), and it is used as a material for cabinets, furniture, etc.

Example 4 A resin liquid for coating was prepared in the same manner as in Example 3, except that 60 parts of unsaturated polyester and 40 parts of diallyl orthophthalate were used.

Using a roll coater, the above resin liquid was continuously coated to 45 g/m2 on thin paper with a basis weight of 30 g/m2 printed with a wood grain pattern, and cured under the same conditions as Example 1 to obtain a cured paper with no surface wrinkles. Obtained.

An ethylene-vinyl acetate adhesive was applied to the back side of the obtained cured paper, and a vinylon nonwoven fabric having a thickness of 0.15 mm and a basis weight of 18 g/m2 was bonded using a roll press to obtain a laminated cured paper.

This laminated cured paper was attached to a 5 mm thick veneer plywood using the above adhesive using a roll press to obtain a decorative board.

This decorative board had excellent solvent resistance, abrasion resistance, and heat resistance, and could withstand high-speed cutting.

It was also possible to perform V-cut and U-cut processing by bending the decorative board at right angles.

Comparative Example 1 The cured paper prepared in Example 1 was directly bonded to a 5 mm thick veneer plywood coated with an ethylene-vinyl acetate adhesive using a roll press to obtain a decorative board.

This decorative board has excellent solvent resistance, abrasion resistance, and heat resistance, and can be easily cut at high speed. It broke.

Examples 1 to 4 and Comparative Example 1, as well as printed plywood A manufactured by a commercially available amino alkyd resin precoating method,
Using Type B2, tests were conducted on the FW type of special plywood according to the Japanese Agricultural Standards and the cut bending workability. The results are shown in Table 1.

Claims (1)

[Claims] 1. A hardened paper is used as a surface layer, which is obtained by applying a solvent-free resin composition containing diallyl phthalates and an air-curing unsaturated polyester to thin paper in an amount of 90 to 170% by weight as a resin content. ■ A method for producing a decorative board that can be cut or bent, characterized by adhering it to a base material using an adhesive through a vinyl chloride sheet or nonwoven fabric.