JP2000218735A - Decorative laminated sheet having outstanding surface hardness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a low-priced decorative laminated sheet suited for a top plate which is free from deformation or surface scratch and has an outstanding surface hardness by bonding a high-density base paper which is processed by a supercalender to a high-density wooden board with a hard adhesive to form a hard top coat layer. SOLUTION: This decorative laminated sheet is formed of a wooden board whose density is set at least to 0.6 g/cm3 and a printed decorative paper laminated on the surface thereof with an adhesive with a top coat applied on the surface. A high-density base paper whose density is set at least to 0.80 g/cm3 with an appropriate decorative pattern printed, is applied with a hard adhesive, and a hard top coat is also applied thereon. Further, the high-density base paper is processed by a supercalender. In the hard adhesive 20-60 pts.wt. hard thermoplastic emulsion resin is mixed to 100 pts.wt. urea resin. In the hard top coat, 5-20 pts.wt. glass bead or alumina is mixed to 100 pts.wt. coating. Thus the wear resistance and scratch hardness of the decorative laminated sheet can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative plate having excellent surface hardness, which can be used for furniture, dwelling machines and dwelling tops.

[0002]

2. Description of the Related Art Conventionally, a decorative surface is smooth and excellent in flexibility.
For the purpose of obtaining a decorative board excellent in durability such as impact resistance and heat crack resistance, a phenolic resin and a diallyl phthalate resin are used between the wooden base material and the pattern paper arranged on both front and back surfaces. It is known that a core paper impregnated with at least one selected resin is interposed, and these are integrally molded and thermoset (Japanese Patent Publication No. 6-67607).

[0003] However, the decorative board has a smooth surface,
Uses resin-impregnated patterned paper to obtain excellent durability such as crack resistance and thermal shock resistance. It is used not only for vertical surfaces such as furniture and walls, but also for tabletops and table surfaces. Can be used also for the top plate of the present invention, and can be used for the same purpose as the present invention. However, the decorative plate is used between the wood-based base material and the pattern paper arranged on both front and back surfaces. In this case, a core paper impregnated with at least one resin selected from a phenol resin and a diallyl phthalate resin is interposed, so that the material is expensive. That is, the core paper is impregnated with a prepreg of a phenol resin or a diallyl phthalate resin and then dried to increase the number of steps and increase the cost.

[0004]

DISCLOSURE OF THE INVENTION The present invention has the same low cost and excellent productivity as conventional printed decorative boards used for vertical decorative surfaces such as furniture and building walls.
In addition, the present invention provides an inexpensive decorative board suitable for a top board having excellent surface hardness, which does not cause deformation of the decorative board or damage to the surface even when concentrated stress is applied or a sharp substance is applied. It is intended for.

[0005]

The present inventors have conducted intensive studies in view of the above-mentioned problems of the prior art, and as a result, bonded a high-density base paper subjected to super calender treatment to a high-density wooden board using a hard adhesive. The present inventors have found that the above problems can be solved by forming a hard top coat layer, and have reached the present invention.

That is, the present invention relates to a decorative board obtained by laminating a printed decorative paper on the surface of a wooden board having a density of 0.6 g / cm ³ or more via an adhesive and applying a top coat on the surface. A decorative board with excellent surface hardness, characterized by sticking a high-density base paper having a density of 0.80 g / cm ³ or more on which a pattern is printed as appropriate using the adhesive described above and applying a hard top coat. A decorative board excellent in surface hardness, characterized in that high-density base paper has been subjected to a super calender treatment. A decorative board excellent in surface hardness, characterized in that the hard adhesive is an adhesive obtained by mixing 20 to 60 parts by weight of a hard thermoplastic emulsion resin with respect to 100 parts by weight of a urea resin. A decorative board having excellent surface hardness, wherein a hard top coat is mixed with 5 to 20 parts by weight of glass beads or alumina based on 100 parts by weight of a paint. It is the gist.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below. According to the Japanese Agriculture and Forestry Standards for special plywood, various physical property values are defined according to the intended use and classified into Class 1, Class 2, Class 3, F type, FW type, W type and the like. Special plywood classified as type F in the above provisions is used for table tops, counters, etc., and is separately provided for Class 1 peeling test or Class 2 dipping peeling test, plane tensile test, moisture content Test, cold repetition A test, water resistance A test, wet heat test, abrasion A test, scratch hardness A test, impact A test, fading A test, contamination A
It is stipulated to pass the test, alkali resistance test, acid resistance test, and thinner resistance test.Special plywood classified as FW type is mainly used for durable walls of buildings and also for furniture. It is stipulated that it shall pass the above-specified tests excluding the internal moisture heat test, and special plywood classified as W type is mainly used for general wall surfaces etc. of buildings Class 1 peel test, Class 2 immersion test or Class 3 immersion test, Plane tensile test, Moisture content test, Cold and heat repetition C test, Water resistance C test, Wear C test, Discoloration B test It is prescribed to pass.

[0008] In order to be classified into the above-mentioned F type, a resin-impregnated base material such as paper, cloth and nonwoven fabric impregnated with a phenol resin, a melamine resin, an unsaturated polyester resin, a diallyl phthalate resin, a guanamine resin, an epoxy resin or the like is usually used. It covers the surface of a substrate such as a plywood or a particle board and heat-clamps to simultaneously bond the surface coating by curing of the resin and the base plate substrate. Therefore, one cycle of processing required 60 seconds or more because of the steps of heating and pressing and curing of the resin, resulting in poor productivity.

The above-mentioned special plywood classified into the FW type or the W type has a lower standard than that classified into the F type, so that a printed decorative paper is attached to the substrate via an adhesive, and the surface of the plywood is optionally used. To form a top coat. Therefore, the above-mentioned special plywood can be continuously produced without requiring a long press, and has excellent productivity and can be obtained at low cost.

According to the present invention, continuous production is possible.
The purpose is to obtain a decorative board having the performance of a special plywood classified into types.

That is, after the surface of a wooden board having a density of 0.6 g / cm ³ or more is polished and smoothed, the density of the base paper appropriately patterned is 0.80 g / cm ³ or more. Are bonded via a hard adhesive to form a hard top coat. The density of the wooden board as the base material is 0.6 g
If it is less than / cm ³ , even if the hardness of the surface is increased, the decorative sheet is likely to be deformed by a slight external force, which is not preferable. The wood board has a density of 0.6 g / cm ³
The above particle board, fiber board, and plywood are preferably used. When the density of the base paper is less than 0.80 g / cm ³ , the required surface hardness cannot be obtained, which is not preferable. The base paper preferably has a range of 20 to 60 g / m ² in terms of handling.

The high-density base paper has a density of 0.80 g / cm ³
Although it is not particularly limited as long as it is the above, those subjected to a super calendar process are preferably used. Super calendering is performed to impart a higher gloss to paper than machine finishing, in which chilled rolls and cotton rolls or paper rolls are alternately stacked. This process improves the appearance of the paper and improves printability. As described above, this processing is for imparting gloss to the paper.
Alternatively, the density is increased by passing through a pressure roll, and a high-density base paper that can be suitably used in the present invention is obtained.

The base paper may be impregnated with an acrylic resin, an epoxy resin or an amino resin in order to increase the hardness. A method for appropriately forming a pattern on the base paper is not particularly limited, but a method using ordinary gravure printing is preferable in terms of cost and the like.

As the hard adhesive used in the present invention, a urea resin, a urea melamine copolymer resin, or a phenol resin is used, and a urea resin or a resin mainly containing the urea resin is most preferable. A thermoplastic resin emulsion is mixed with 20 to 60 parts by weight, preferably 20 to 40 parts by weight, based on 100 parts by weight of the mixture. Parts by weight).

As the above-mentioned thermoplastic resin emulsion, those having a high softening temperature (50 ° C. or higher), for example, unplasticized vinyl acetate emulsion and SBR emulsion, preferably styrene-rich (styrene content of 50 to 80% by weight) SBR emulsion are suitable. Used. By adding the thermoplastic resin emulsion to the adhesive, it is possible to prevent the adhesive from bleeding from the high-density base paper.
If the amount of the thermoplastic resin emulsion is less than 20 parts by weight, the effect of preventing stains cannot be obtained, and if it exceeds 60 parts by weight, the hardness is undesirably reduced.

As a method of bonding the high-density base paper to the surface of the particle board by using a hard adhesive, it can be used without changing a commonly used laminator machine. By pressing a high-density base paper for a short time (5 to 10 seconds) with a press machine for short time (5 to 10 seconds), the surface is finished smoothly and the adhesive penetrates the base paper to increase the hardness, which is preferable.

Next, a hard top coat layer is formed on the surface of the decorative plate on which the high-density base paper is bonded. As the resin for forming the top coat layer, a urethane-based resin, an amino-based resin, or an acrylic-based resin is used, but a resin having high crosslinking reactivity is preferable. In addition to the above resins, ultraviolet-curable polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligomer acrylate, alkyd acrylate,
Acrylic paints and unsaturated polyester paints using a polyol acrylate as a prepolymer can be used, and these are preferable because of excellent workability.

Glass beads or alumina can be mixed into the top coat layer formed of each of the above-mentioned resins and paints in order to further impart abrasion resistance. Glass beads and alumina are preferably powders or granules having a diameter of 10 to 100 μm. If it is less than 10 μm, sufficient abrasion resistance cannot be obtained, and if it exceeds 100 μm, the surface smoothness is impaired, which is not preferable. The amount of these additives is preferably 5 to 20 parts by weight based on 100 parts by weight of the resin. If the amount is less than 5 parts by weight, no improvement in abrasion resistance is observed, and if it exceeds 20 parts by weight, the horizontal tensile strength, impact strength and the like are undesirably reduced.

[0019]

The present invention will be specifically described below with reference to examples. In the following examples, the reason that it was judged that the results of only the abrasion resistance A test and the scratch hardness test A passed the standard of the F type was that the above two tests were the most important items for the present invention, This is because the correlation between the test items other than the above two items and the configuration requirements of the present invention is not as large as the relationship between the above two items. In Table 1, "parts" represents parts by weight. The test was performed as follows. <Abrasion resistance A test> After measuring the weight of the test side, fix it horizontally on a turntable and polish paper (thermosetting decorative board test method (JIS
K6902 (1963)), two rubber disks (thermosetting decorative plate test method (JIS K6902 (1963))) around which two rubber discs are wound, and a test is performed. Is read, the weight of the test piece is measured, and the wear value and the wear amount are determined. <Scratch hardness test A> A test piece is fixed horizontally on a mounting table, a weight of 200 g is applied using a diamond needle, and three linear scratches having a length of 50 mm are formed on the surface of the test piece.

Examples 1 to 3 Comparative Examples 1 to 5
A decorative board was produced on the surface of a particle board having a specific gravity of 0.7 g / cm ^{3 according to} the specifications shown in Table 1. The pressing conditions were 130 ° C., 5 seconds, 15 kg / m ² when the adhesive was urea resin, and 80 ° C., 5 seconds, 15 kg / m ² when the adhesive was vinyl acetate resin. The ultraviolet irradiation condition was an 80 W / cm lamp for 5 seconds. In the evaluation, those that passed the criteria of the F type were evaluated as unsatisfactory. That is, in the wear resistance A test, the wear value is 100 or more and the wear amount is 0.1 g or less, and in the scratch hardness A test, the depth of the flaw applied to the test piece is 10 μm or less. Those that satisfied were judged to be acceptable.

[0021]

[Table 1] Abbreviations and samples in the table are as follows. In the column of printed decorative paper, 30 g / m ² SC treatment d: 0.85 g / cm ³ means that the weight per square meter of decorative paper is 30 g,
It means that the decorative paper has been super calendered and its density is 0.85 g / cm ³ . In the column of top coat, UA / Gl ₁₀ (Al ₅ ) 80 g / m ² means that 80 g of a mixture of 100 parts by weight of urethane acrylate resin mixed with 10 parts by weight of glass beads (5 parts by weight of alumina) is applied per square meter. Means you did. SC treatment: Super calender treatment UA: Urethane acrylate (Dainippon Ink part number KBB
-07) Gl: Glass beads (Toshiba barotini part number GB-73
1) Urethane: Dainippon Ink UV Clear Urea Resin Adhesive: Oshika Shinko Part No. LS-12A Vinegar: Vinyl acetate resin emulsion (Konishi Part No. CH-
7) SBR impregnated paper: Kojin GF sheet

[0022]

As described above, the decorative board of the present invention has a density of 0.80 g / cm ³ or more on the surface of a wooden board having a density of 0.6 g / cm ³ or more via a hard adhesive. The top plate used for table tops, counters, etc. that meets the F-type standards can be continuously produced at low cost. In particular, a high-density base paper with a density of 0.80 g / cm ³ or more super-calendered is bonded to the surface of a particle board with a density of 0.6 g / cm ³ or more through a hard adhesive mixed with a hard thermoplastic emulsion,
When a top coat mixed with glass beads or alumina is applied, a top plate having excellent wear resistance and high scratch hardness can be obtained at low cost.

Continued on the front page (72) Inventor Kimitaka Takubo 1515 Nakatsu-cho, Marugame-shi, Kagawa Prefecture F-term in Okura Industrial Co., Ltd. (reference) 4D075 CA02 CA03 CA04 DB21 DC02 DC32 DC38 EA13 EA17 EA35 EC02 EC03 EC24 4F100 AA19H AG00H AK01C AK22GAK25 AK36G AK51 AL01 AL05G AP03A BA03 BA07 BA10A BA10C DE01H DG10B EH46C EJ19 EJ192 EJ54 EJ542 GB08 HB00B JA13A JA14B JB16G JK12 JK12C JK12G JM01G YY00A YY00B

Claims (4)

[Claims] 1. A decorative board obtained by attaching a printed decorative paper to a surface of a wooden board having a density of 0.6 g / cm ³ or more through an adhesive and applying a top coat to the surface. A decorative board with excellent surface hardness, characterized by sticking a high-density base paper having a density of 0.80 g / cm ³ or more on which a pattern is appropriately printed by using, and applying a hard top coat. 2. The decorative plate having excellent surface hardness according to claim 1, wherein the high-density base paper is subjected to a super calender treatment. 3. The surface hardness according to claim 1 or 2, wherein the hard adhesive is an adhesive obtained by mixing 20 to 60 parts by weight of a hard thermoplastic emulsion resin with respect to 100 parts by weight of a urea resin. Excellent veneer. 4. A hard top coat according to claim 1, wherein 5 to 20 parts by weight of glass beads or alumina is mixed with 100 parts by weight of the coating material. Excellent veneer.