JP2011136510A - Thermosetting resin decorative sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin decorative sheet having excellent adhesion, heat resistance and chemical resistance, besides adaptability to contamination resistance, scratch resistance, water resistance, and weatherability. <P>SOLUTION: The thermosetting resin decorative sheet 1 is formed by laminating a thermosetting resin-impregnated core layer 21, a design layer 22, a primer layer 3 and a surface protective layer 4 in this order, and by heating and pressure molding. The surface protective layer 4 is formed by crosslinking and curing an ionizing radiation curable resin. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a thermosetting resin decorative board.

  Thermosetting resin decorative boards have excellent properties in impact resistance, stain resistance, pencil hardness, and the like. Specifically, high-pressure melamine resin decorative boards, low-pressure melamine resin decorative boards, diallyl phthalate (DAP) ) Resin decorative board, polyester decorative board, guanamine resin decorative board, phenolic resin decorative board, and the like. Among these, the high-pressure melamine resin decorative board has a hard surface, excellent heat resistance, stain resistance, chemical resistance, and a variety of design patterns, so it can be selected from table tops, sinks, and desk tops. Widely used for boards.

  A thermosetting resin decorative board generally impregnates a decorative paper having a pattern printed on the surface of the paper with a thermosetting resin, arranges an overlay paper impregnated with the thermosetting resin on the surface of the decorative paper, and heats the back side. It is manufactured by stacking core paper impregnated with a paper base material such as kraft paper with a curable resin, sandwiching it between metal plates, and laminating at high temperature and high pressure. For example, high-pressure melamine resin decorative boards generally impregnate melamine resin on decorative paper with a pattern printed on the surface of the paper, arrange overlay paper impregnated with melamine resin on the surface of the decorative paper, and phenolic resin or the like on the back surface. It is manufactured by stacking core paper impregnated with a paper base material such as kraft paper with thermosetting resin, and sandwiching it between metal plates at high temperature and high pressure.

By the way, since the high-pressure melamine resin decorative board is particularly excellent in chemical resistance, there is a high demand for a desk top board among desks. However, in order to improve the surface characteristics such as chemical resistance, the resin decorative board is used. There has been proposed a decorative board provided with a coating film cured by active energy rays by a technique such as transfer on the surface of the board (for example, Patent Documents 1 and 2).
However, these decorative boards have insufficient adhesion between the coating film cured by active energy rays and the resin decorative board, and the coating film peels off or the coating film swells when heated. However, it was not satisfactory in terms of adhesion and heat resistance.

Japanese Patent Laid-Open No. 1-119347 JP 2002-264288 A

  Under such circumstances, the present invention provides a thermosetting resin cosmetic that is excellent in adhesion, heat resistance, and chemical resistance in addition to suitability for use such as stain resistance, scratch resistance, water resistance, and weather resistance. The purpose is to provide a board.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above problems can be solved by the following invention. That is, this invention provides the following thermosetting resin decorative board and its manufacturing method.

1. A thermosetting resin decorative board obtained by laminating a thermosetting resin-impregnated core layer, a design layer, a primer layer, and a surface protective layer in this order, and obtained by heating and pressing.
2. 2. The thermosetting resin decorative board according to 1 above, wherein the primer layer is obtained by subjecting the surface on the surface protective layer side to an easy adhesion treatment.
3. After providing the primer layer and the surface protective layer by transfer so that the primer layer is on the design layer side on the design layer of the laminate formed by sequentially laminating the thermosetting resin-impregnated core layer and the design layer A method for producing a thermosetting resin decorative board, characterized by heat-molding.
4). Thermosetting, characterized by heat-molding after providing a surface protective layer on a primer layer of a laminate comprising a thermosetting resin-impregnated core layer, a design layer and a primer layer in order. Manufacturing method of resin decorative board.
5. 6. The method for producing a thermosetting resin decorative board according to 4 or 5 above, wherein the primer layer is obtained by subjecting the surface on the surface protective layer side to an easy adhesion treatment.

  According to the present invention, it is possible to provide a thermosetting resin decorative board having excellent adhesion, heat resistance, and chemical resistance in addition to suitability for use such as stain resistance, scratch resistance, water resistance, and weather resistance. it can.

It is a schematic diagram which shows the cross section of the thermosetting resin decorative board of this invention. It is a schematic diagram which shows the layer structure at the time of transcription | transfer in the manufacturing method of the thermosetting resin decorative board of this invention.

[Thermosetting resin decorative board]
The thermosetting resin decorative board of the present invention is obtained by laminating a thermosetting resin-impregnated core layer, a design layer, a primer layer, and a surface protective layer in this order, and is obtained by heating and pressing. Hereinafter, the thermosetting resin decorative board of the present invention will be described in detail with reference to FIG.

<< Thermosetting resin-impregnated core layer 21 >>
The thermosetting resin-impregnated core layer 21 gives the necessary thickness and strength to the thermosetting decorative board 1 of the present invention, and is thermoset on unbleached kraft paper having a basis weight of about 100 to 200 g / m ^2. A core paper impregnated with a conductive resin is preferably used. Although there is no restriction | limiting in particular as the amount of impregnation of this thermosetting resin, Usually, it is about 20-50 mass%. The number of core papers is appropriately selected according to the thickness of the thermosetting resin decorative board. Furthermore, the core paper can be heated and pressurized in advance to melt and solidify the resin, thereby smoothing the surface of the core paper.

  In the present invention, the thermosetting resin is preferably a phenol resin, a melamine resin, a diallyl phthalate (DAP) resin, a polyester resin, a guanamine resin, etc., from the viewpoint of heat resistance, chemical resistance, etc. A melamine resin is more preferable.

  In addition, as the core layer 21, for example, veneer of various materials such as cedar, firewood, firewood, pine, lawan, teak, melapy, etc., wood material such as wood veneer, wood plywood, particle board, medium density fiberboard (MDF), etc. Can also be used. These can be used alone or in a laminated manner.

  A backer layer made of a fibrous base material or a wooden base material impregnated with a thermosetting resin may be provided on the back surface of the core layer 21 for warpage prevention. For warping prevention, a method of bonding a synthetic resin film such as vinyl chloride, polyethylene, or polypropylene, a method of bonding a sheet composed of two layers of paper and a synthetic resin, and a paper substrate such as two thin papers And a method of laminating a paper-based sheet formed by adhesion through an extrusion coating layer of a polyolefin resin such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer. In addition, there is a method in which a moisture-proof sheet composed of a synthetic resin base material layer and a vapor deposition layer is attached to the back surface of the core layer 21.

<< Design layer 22 >>
The design layer 22 is not particularly limited as long as the melamine resin impregnated with the thermosetting resin-impregnated core layer 21 permeates in the manufacturing process of the thermosetting resin decorative board of the present invention. Titanium paper, coated paper, art paper, sulfate paper, glassine paper, parchment paper, paraffin paper, Japanese paper, and the like can be used, and those with high concealment properties such as titanium paper are particularly preferably used.
Moreover, these materials are (i) what is printed with a pattern, (ii) what is printed uniformly (solid print) over the entire surface, and (iii) pre-colored according to the use. You may select suitably from what is used (colored titanium paper etc.). For example, when the thermosetting resin decorative board of the present invention is used as an experimental table, it is preferable to employ one that is uniformly and uniformly printed in black over the entire surface, or colored titanium paper that has been colored in advance in black. it can.

The thickness of the design layer 22, the range from the viewpoint of permeability and concealment of 30 to 120 g / m ² of melamine resin is preferable, more preferably in the range of 60~80g / m ^2.

  Moreover, the material which forms the design layer 22 may be impregnated with a thermosetting resin in advance from the viewpoint of improving chemical resistance. Examples of the thermosetting resin include the same resins as those used in the core layer 21 described above. When the decorative board of the present invention is used as an experimental table, it is a melamine resin particularly from the viewpoint of chemical resistance. Is preferred.

<< Thermosetting resin-impregnated overlay layer 23 >>
The thermosetting resin-impregnated overlay layer 23 is a layer provided on the design layer 22 as desired for the purpose of improving the strength of the decorative board of the present invention. As the overlay layer 23, an overlay base paper that is usually used for a thermosetting resin decorative board is preferably impregnated with a thermosetting resin.
Examples of the thermosetting resin include the same resins as those used in the core layer 21 described above. When the decorative board of the present invention is used as an experimental table, it is a melamine resin particularly from the viewpoint of chemical resistance. Is preferred.

  Although there is no restriction | limiting in particular as the amount of impregnation of this thermosetting resin, Usually, it is about 20-50 mass%. If it is within the range, sufficient chemical resistance can be obtained.

<< Primer layer 3 >>
The decorative board of the present invention has the primer layer 3 from the viewpoint of improving the adhesion between the design layer 22 or the thermosetting resin-impregnated overlay layer 23 provided as desired and the surface protective layer 4.
Preferable examples of the binder resin for forming the primer layer include polyester-based, polyether-based, acrylic-based, and polycarbonate-based thermoplastic urethane resins, and these are preferably used alone or in combination. In particular, from the viewpoint of adhesion, polyester and acrylic are preferable, and polyester is particularly preferable.

As a specific example of such a thermoplastic urethane resin, a urethane resin composed of a linear polymer obtained by reacting a polyol having a hydroxyl group at a terminal and a polyisocyanate can be exemplified.
As a polyol, polyester polyol, polyether polyol, polycarbonate polyol, etc. are mentioned preferably, for example, More preferably, it is a polyester polyol. More specifically, the polyester polyol includes poly (ethylene adipate), poly (butylene adipate), poly (neopentyl adipate), poly (hexamethylene adipate), poly (butylene azelate), poly (butylene sebacate). ) And polyester diols such as polycaprolactone. In addition, acrylic polyol, urethane polyol and the like are also preferable. These are used alone or in combination of two or more.

  Examples of the diisocyanate component include various aliphatic (or alicyclic) or aromatic diisocyanates conventionally known in the polyurethane field. For example, aliphatic (or alicyclic) systems include aliphatic isocyanates such as 1,6-hexamethylene diisocyanate, alicyclic isocyanates such as isophorone diisocyanate and hydrogenated tolylene diisocyanate, 2,4-tolylene diisocyanate, Aromatic isocyanates such as 2,6-tolylene diisocyanate, xylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, and the like. These can be used alone or in combination of two or more.

The glass transition temperature of the urethane-based resin is preferably in the range of −70 to −15 ° C., more preferably −60 to −20 ° C. from the viewpoint of improving adhesion.
The number average molecular weight of the urethane-based resin is preferably 10,000 to 70,000, more preferably 20,000 to 70,000, and further preferably 25,000 to 65,000, from the viewpoint of improving adhesion.

  50 mass% or more is preferable, as for content of the urethane-type resin in the binder resin which forms the primer layer 3, 80 mass% or more is more preferable, and 90 mass% or more is further more preferable. When the content of the urethane-based resin is within the above range, the adhesion can be improved.

  In addition, as a resin that can be used in combination with the urethane resin as the binder resin for forming the primer layer 3, acrylic resin, polyester resin, polycarbonate resin, polyolefin resin, polyvinyl alcohol resin, polyvinyl acetal resin, etc. Thermosetting resins, such as a thermoplastic resin and a melamine resin, are mentioned. Among these, considering the reactivity with the thermosetting resin, a polyvinyl alcohol resin or a polyvinyl acetal resin can be used. Of these, polyvinyl butyral resin is preferable.

  The thickness of the primer layer 3 is preferably 5 to 50 μm, more preferably 25 to 50 μm, and still more preferably 30 to 40 μm. When the thickness of the primer layer 3 is within the above range, the effect of improving adhesion can be sufficiently obtained. Moreover, the easy adhesion process 5 described later is also facilitated.

(Easy adhesion treatment 5)
The decorative board of the present invention is preferably subjected to an easy adhesion treatment 5 on the surface protective layer 4 side of the primer layer 3 in order to improve the adhesion.
Examples of the easy adhesion treatment include physical or chemical surface treatments such as an oxidation method and an unevenness method, and chemical surface treatment is preferred. As the chemical surface treatment, corona discharge treatment, ozone treatment, chromium oxidation treatment and the like are preferably mentioned, and corona discharge treatment is preferred from the viewpoint of improving adhesion and operability.

<< Surface protective layer 4 >>
The surface protective layer 4 is preferably one obtained by crosslinking and curing the ionizing radiation curable resin composition from the viewpoint of obtaining excellent chemical resistance. Here, the ionizing radiation curable resin composition is one having an energy quantum capable of crosslinking and polymerizing molecules in an electromagnetic wave or a charged particle beam, that is, crosslinking or curing by irradiating ultraviolet rays or electron beams. Refers to a resin composition.

(Ionizing radiation curable resin composition)
As the ionizing radiation curable resin used for the surface protective layer 4, a conventionally known compound may be appropriately used. Specifically, it can be appropriately selected from polymerizable monomers, polymerizable oligomers or prepolymers conventionally used as ionizing radiation curable resins, but from the viewpoint of obtaining good curing characteristics, Those that are difficult to out, have a coating property even as a solid content standard of about 95 to 100%, and are less likely to cause shrinkage during curing. Representative examples of such ionizing radiation curable resins are described below. “(Meth) acrylate” means “acrylate or methacrylate”.

  As the polymerizable monomer, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is suitable, and in particular, a polyfunctionality having two or more ethylenically unsaturated bonds in the molecule ( (Meth) acrylate is preferred, and one kind may be used alone, or two or more kinds may be used in combination. As a functional group number, 2-8 are preferable, 2-6 are more preferable, and 3-4 are more preferable.

  In the present invention, together with the polyfunctional (meth) acrylate, for the purpose of adjusting the viscosity, monofunctional (meth) acrylates such as methyl (meth) acrylate are within a range that does not impair the purpose of the present invention. It can be used together as appropriate. A monofunctional (meth) acrylate may be used individually by 1 type, and may be used in combination of 2 or more type.

  Next, as the polymerizable oligomer, an oligomer having a radically polymerizable unsaturated group in the molecule, for example, epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) Preferred examples include acrylate oligomers. Among these oligomers, polyfunctional polymerizable oligomers are preferable, and the number of functional groups is preferably 2 to 16, more preferably 2 to 8, and still more preferably 2 to 6.

  Furthermore, other polymerizable oligomers include polybutadiene (meth) acrylate oligomers with high hydrophobicity that have (meth) acrylate groups in the side chain of polybutadiene oligomers, and silicone (meth) acrylate oligomers that have polysiloxane bonds in the main chain. In a molecule such as an aminoplast resin (meth) acrylate oligomer modified with an aminoplast resin having many reactive groups in a small molecule, or a novolak type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc. There are oligomers having a cationic polymerizable functional group. These polymerizable oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  When an ultraviolet curable resin is used as the ionizing radiation curable resin, it is desirable to add about 0.1 to 5 parts by mass of a photopolymerization initiator with respect to 100 parts by mass of the ultraviolet curable resin. The initiator for photopolymerization can be appropriately selected from those conventionally used and is not particularly limited.

In the present invention, it is preferable to use an electron beam curable resin as the ionizing radiation curable resin. This is because the ionizing radiation curable resin composition in the present invention contains an ultraviolet absorber, and in the case of irradiation with ultraviolet rays, the ultraviolet irradiation amount may be insufficient. Although preparation may be required, in the case of electron beam irradiation, such preparation is unnecessary, and stable curing characteristics can be obtained efficiently.

<Various additives>
Various additives are blended in the curable resin composition used in the present invention according to the desired physical properties of the surface protective layer 4 to be obtained. Examples of the additive include a polymerization inhibitor, a crosslinking agent, an antistatic agent, an adhesion improver, an antioxidant, a leveling agent, a thixotropic agent, a coupling agent, a plasticizer, an antifoaming agent, a filler, and a solvent. Is mentioned. Moreover, antiblocking agents, such as a silica, can also be added in order to prevent blocking of the transfer sheet described later.

[Method for producing thermosetting resin decorative board]
The manufacturing method of the thermosetting resin decorative board of the present invention is characterized by manufacturing by transfer. More specifically, (i) a primer layer and a surface protective layer are formed on the design layer of the laminate obtained by sequentially laminating a thermosetting resin-impregnated core layer and a design layer, and the primer layer is on the design layer side. Or (ii) a surface protective layer on the primer layer of the laminate formed by sequentially laminating a thermosetting resin-impregnated core layer, a design layer, and a primer layer. Is provided by transfer and then heat-processed, and the thermosetting resin decorative board of the present invention is preferably produced by these production methods.

<Transfer sheet 11>
In the production method of the present invention, as shown in FIG. 2, the transfer sheet 11 is preferably formed by laminating the surface protective layer 4 or the surface protective layer 4 and the primer layer 3 in this order on the transfer sheet substrate 12. Used.

(Transfer sheet substrate 12)
As the substrate 12 of the transfer sheet preferably used in the production method of the present invention, a general plastic film or plastic sheet is used.
Examples of the plastic film or plastic sheet include those made of various synthetic resins. Synthetic resins include low density polyethylene resins (including linear low density polyethylene resins), medium density polyethylene resins, high density polyethylene resins, ethylene-α olefin copolymers, polypropylene resins, polymethylpentene resins, polybutene resins, ethylene. -Polyolefin resins such as propylene copolymer, propylene-butene copolymer, olefinic thermoplastic elastomer or a mixture thereof; polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate-isophthalate copolymer resin, polyester heat Polyester resins such as plastic elastomers; Acrylic resins such as poly (meth) methyl acrylate resin, poly (meth) ethyl acrylate resin, poly (meth) butyl acrylate resin; nylon 6 or Polyamide resins represented by like nylon 66; polystyrene resins; polycarbonate resins; polyarylate resin; cellulose triacetate resins, cellulose resins such as cellophane and the like or a polyimide resin.

  The surface of the transfer sheet substrate 12 on which the surface protective layer 4 is provided can be subjected to embossing or matting for the purpose of improving the design of the decorative board. In addition, for the purpose of improving the adhesion between the transfer sheet substrate 12 and the surface protective layer 4, it is possible to perform the surface treatment adopted in the above-described easy adhesion treatment.

  The thickness of the transfer sheet substrate 12 is usually about 1 to 500 μm, and considering the strength and production efficiency of the substrate, 10 to 200 μm is preferable, and 10 to 100 μm is more preferable.

(Method for forming surface protective layer 4)
The transfer sheet 11 preferably used in the production method of the present invention has a surface protective layer 4, and the surface protective layer 4 is laminated on a thermosetting resin decorative board by transfer.
The surface protective layer 4 is formed on the transfer sheet substrate 12 as follows.
First, the above-mentioned ionizing radiation curable component, which is a polymerizable monomer, a polymerizable oligomer, and various additives, are uniformly mixed at predetermined ratios to prepare a coating liquid composed of an ionizing radiation curable resin composition. The viscosity of the coating solution is not particularly limited as long as it is a viscosity capable of forming an uncured resin layer on the coated surface by a coating method described later.
Thus, it is necessary to apply the coating solution prepared in a coating amount larger than 5 g / m ² , and the coating amount is preferably larger than 6 g / m ² . Moreover, the upper limit of the coating amount is usually about 45 g / m ² , preferably 35 g / m ² . The coating liquid is applied by a known method such as gravure coating, bar coating, roll coating, reverse roll coating, or comma coating, preferably by gravure coating, to form an uncured resin layer.

The uncured resin layer thus formed is irradiated with ionizing radiation such as an electron beam and ultraviolet rays to cure the uncured resin layer. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin used and the thickness of the layer, but the uncured resin layer is usually cured at an acceleration voltage of about 70 to 300 kV. preferable.
In electron beam irradiation, the transmission capability increases as the acceleration voltage increases. Therefore, when using a base material that deteriorates due to the electron beam as the base material, the transmission depth of the electron beam and the thickness of the resin layer are substantially equal. By selecting the accelerating voltage so as to be equal to each other, it is possible to suppress the irradiation of the electron beam to the base material, and to minimize the deterioration of the base material due to the excessive electron beam.
The irradiation dose is preferably such that the crosslinking density of the resin layer is saturated, and is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 70 kGy (1 to 7 Mrad).

The electron beam source is not particularly limited, and for example, various electron beam accelerators such as a Cockloft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type are used. be able to.
When ultraviolet rays are used as the ionizing radiation, those containing ultraviolet rays having a wavelength of 190 to 380 nm are emitted. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a carbon arc lamp, etc. are used.

  The cured resin layer thus formed has various functions by adding various additives, for example, a so-called hard coat function, anti-fogging coat function, and anti-fouling coat having high hardness and scratch resistance. A function, an antiglare coating function, an antireflection coating function, an ultraviolet shielding coating function, an infrared shielding coating function and the like can also be imparted.

(Method for forming primer layer 3)
After forming the surface protective layer 4 as described above, the primer layer 3 is formed. Specifically, the coating liquid containing the binder resin for forming the primer layer 3 is applied and formed by a known coating method. At that time, the primer layer 3 is coated so that the thickness thereof is preferably in the range of 5 to 50 μm, more preferably 25 to 50 μm, and still more preferably 30 to 40 μm, as described above.
Furthermore, after forming the primer layer 3, it is preferable to perform the above easy adhesion treatment for the purpose of obtaining better adhesion.

<Heat processing molding>
In the production method of the present invention, the heat forming is performed by laminating a thermosetting resin-impregnated core layer 21, a design layer 22, and a thermosetting resin-impregnated overlay layer 23 preferably provided in this order, and further laminating the transfer sheet 11. Use a heating and pressurizing machine. Here, when the transfer sheet 11 has the surface protective layer 4, the surface protective layer 4 and the design layer 22 (or the thermosetting resin-impregnated overlay layer 23) are overlapped. When the transfer sheet 11 has the surface protective layer 4 and the primer layer 3, the primer layer 3 and the design layer 22 (or the thermosetting resin-impregnated overlay layer 23) are overlapped with each other.

As the heating and pressurizing machine used for the heat forming, a flat plate press machine using a multi-stage hot press is used. Conditions such as pressure, temperature, and time for heating and pressurization can be appropriately selected according to the material to be used, but the normal pressure is 0.1 to 9.8 MPa (1 to 100 kg / cm ² ), and the temperature is 100 to 200 ° C. The time is about 10 seconds to 120 minutes. When manufacturing a so-called high-pressure melamine resin decorative board using melamine as a thermosetting resin and using the curable resin-impregnated core layer 21, the design layer 22, and the thermosetting resin-impregnated overlay layer 23, 9.9 to 9.8 MPa (60 to 100 kg / cm ² ), preferably 5.9 to 7.8 MPa (60 to 80 kg / cm ² ), the temperature is 110 to 160 ° C., preferably 130 to 150 ° C., and the time is 10 -60 minutes, preferably about 30-40 minutes.

A thermosetting resin decorative board can be obtained by peeling the transfer sheet substrate 12 after the heat processing molding.
The thermosetting resin decorative board produced in this way is arbitrarily cut, and the surface and the mouth end are subjected to optional decoration such as grooving and chamfering using a cutting machine such as a router or cutter. Can do. And it can use widely for various uses, for example, a table top, a sink, a top plate of a desk.
In addition to the suitability for use such as contamination resistance, scratch resistance, water resistance, weather resistance, etc., it also has excellent adhesion, heat resistance, and chemical resistance. It can be suitably used for the top plate.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example.
(Evaluation methods)
The decorative sheet obtained in each example was evaluated by the following methods.
(1) Evaluation of chemical resistance In accordance with JIS K 7114, test pieces (2 cm long x 4 cm wide) of the resulting decorative plate were treated with various chemicals (sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, formic acid, acetic acid, citric acid, shu (Acid, sodium hydroxide) was added dropwise and allowed to stand at room temperature (23 ° C.) for 24 hours, and the appearance change of the test piece was measured and observed, and evaluated according to the following evaluation criteria.
A: The state of the surface does not change. B: A part of the surface is discolored or roughened, but it is minor and has no practical problem. C: The surface is remarkably discolored or roughened. (2) Evaluation of stain resistance Contaminant ( Acidic detergent: Saint Paul, alkaline detergent: domestic, diethyl ether, hexane, tetrahydrofuran, ethyl acetate, xylene, chloroform, benzene, aniline, acetone, methanol, formalin, carbon disulfide, carbon tetrachloride, ammonia water) It was applied to the surface of a test piece (length 2 cm × width 4 cm), and the remaining state of contaminants was observed visually when wiped off after 24 hours. Judgment criteria were evaluated as follows.
A: No contaminant remains B: Contaminant remains minor but no problem in practical use C: Contaminant remains remarkably (3) Adhesion evaluation (cellophane tape resistance)
After cutting a part of the surface of the decorative board test piece (length 2 cm x width 4 cm) into an X shape with a knife, cellophane tape (cellophane adhesive tape manufactured by Nichiban Co., Ltd., “ Cellophane tape (registered trademark) “25 mm width) was strongly adhered, and the cellophane tape was forcibly peeled in the direction of 90 degrees from the decorative plate surface. The surface state when this was repeated 10 times was observed.
(4) Evaluation of boiling test The surface of the test piece after performing a boiling test on a decorative board test piece (2 cm long x 4 cm wide) in accordance with JIS K6902 is visually observed, and the following criteria are determined: It was evaluated by.
A: No swelling / whitening was confirmed. B: Swelling / whitening was confirmed to some extent, but there was no problem in practical use. C: Significant swelling / whitening was confirmed.

Example 1
An electron beam made of a mixture of urethane acrylate and a polyfunctional monomer, using a PET film (thickness 100 μm, “U4 (trade name)” (Matte easy-to-slip type), manufactured by Teijin DuPont Films Ltd.) as the transfer sheet substrate 12. A curable resin composition was applied at a coating amount of 30 g / m ² by a gravure offset coater method, and a urethane acrylic resin (number average molecular weight: 60,000) as a binder resin was silica, average particle size: 0.1 μm ) Is added to a composition containing 2.5% by mass of a curing agent (XDI isocyanate, manufactured by Showa Ink Industries, Ltd.) with respect to 100 parts by mass of the binder resin, a coating amount of 20 g / Coating was performed by gravure printing at m ² . Next, an electron beam with an acceleration voltage of 125 kV and an irradiation dose of 50 kGy (5 Mrad) is irradiated to cure the electron beam curable resin composition, and the surface protective layer 4 and the primer layer 3 are sequentially formed on the transfer sheet substrate 12. A laminated transfer sheet 11 was obtained.

Apart from the production of the transfer sheet 11, the thermosetting resin-impregnated core layer 21 is obtained by impregnating 30% by mass of phenol resin with phenol-impregnated kraft paper (Ota Sangyo Co., Ltd., weighing 200 g / m ² kraft paper). ), Black titanium paper (weighing 80 g / m ² ) as the design layer 22, 300 mass% melamine resin on the overlay paper (weighing 22 g / m ² paper (made by Mead)) as the thermosetting resin-impregnated overlay layer 23 (Obtained by impregnation with Cymel)).

The above phenol impregnated kraft paper, black titanium paper and overlay paper are stacked in this order, and the transfer sheet 11 is stacked so that the overlay paper and the primer layer 3 are in contact with each other, and then sandwiched between the end plates, and the pressure is 7.8 MPa ( 80 kg / cm ² ) at a temperature of 145 ° C. for 30 minutes, and the resin was permeated, cured and integrated to obtain a thermosetting resin decorative board (high-pressure melamine decorative board). The obtained decorative board was allowed to stand for one day, and then cut into a test piece measuring 2 cm long × 4 cm wide, and each of the above evaluations was performed. The results of evaluation are shown in Table 1.

Example 2
In Example 1, a decorative board was produced in the same manner as in Example 1 except that the corona discharge treatment was performed after the primer layer 3 was formed. Each evaluation mentioned above was performed about the obtained test piece. The results of evaluation are shown in Table 1.

Examples 3 and 4
In Example 2, a decorative board was produced in the same manner as in Example 2, except that the binder resin used for forming the primer layer 3 was changed to that shown in Table 1. Each evaluation mentioned above was performed about the obtained test piece. The results of evaluation are shown in Table 1.

Comparative Example 1
In Example 1, a decorative board was produced in the same manner as in Example 1 except that the primer layer 3 was not formed. Each evaluation mentioned above was performed about the obtained test piece. The results of evaluation are shown in Table 1.

  According to the present invention, it is possible to obtain a thermosetting resin decorative board having excellent adhesion, heat resistance, and chemical resistance in addition to suitability for use such as contamination resistance, scratch resistance, water resistance, and weather resistance. .

1. Thermosetting resin decorative board 21. Thermosetting resin impregnated core layer 22. Design layer 23. 2. Thermosetting resin impregnated overlay layer Primer layer 4. 4. Surface protective layer Easy adhesion treatment11. Transfer sheet 12. Transfer sheet base material

Claims (16)

  A thermosetting resin decorative board obtained by laminating a thermosetting resin-impregnated core layer, a design layer, a primer layer, and a surface protective layer in this order, and obtained by heating and pressing.   The thermosetting resin decorative board according to claim 1, wherein the primer layer is obtained by subjecting the surface on the surface protective layer side to an easy adhesion treatment.   The thermosetting resin decorative board according to claim 1 or 2, wherein the surface protective layer is formed by crosslinking and curing an ionizing radiation curable resin.   The thermosetting resin decorative board according to any one of claims 1 to 3, wherein the binder resin forming the primer layer contains a urethane resin.   The thermosetting resin decorative board according to claim 4, wherein the content of the urethane-based resin in the binder resin is 50% by mass or more.   The thermosetting resin decorative board according to claim 4 or 5, wherein the urethane resin has a glass transition temperature of -70 to -15 ° C.   The thermosetting resin decorative board according to any one of claims 4 to 6, wherein the urethane resin is polyester urethane.   The thermosetting resin decorative board according to any one of claims 1 to 7, which is used for an experimental table.   After providing the primer layer and the surface protective layer by transfer so that the primer layer is on the design layer side on the design layer of the laminate formed by sequentially laminating the thermosetting resin-impregnated core layer and the design layer A method for producing a thermosetting resin decorative board, characterized by heat-molding.   Thermosetting, characterized by heat-molding after providing a surface protective layer on a primer layer of a laminate comprising a thermosetting resin-impregnated core layer, a design layer and a primer layer in order. Manufacturing method of resin decorative board.   The method for producing a thermosetting resin decorative board according to claim 9 or 10, wherein the primer layer is obtained by subjecting the surface on the surface protective layer side to an easy adhesion treatment.   The method for producing a thermosetting resin decorative board according to any one of claims 9 to 11, wherein the surface protective layer is formed by crosslinking and curing an ionizing radiation curable resin.   The method for producing a thermosetting resin decorative board according to any one of claims 9 to 12, wherein the binder resin forming the primer layer contains a urethane resin.   The method for producing a thermosetting resin decorative board according to claim 13, wherein the content of the urethane-based resin in the binder resin is 50% by mass or more.   The method for producing a thermosetting resin decorative board according to claim 13 or 14, wherein the urethane resin has a glass transition temperature of -70 to -15 ° C.   The method for producing a thermosetting resin decorative board according to any one of claims 13 to 15, wherein the urethane resin is polyester urethane.

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