Resin composition for decorative board, decorative sheet, and decorative board

Abstract

To provide a resin composition for a decorative plate capable of providing an incombustible decorative plate that achieves at least one of excellent releasability from a mirror plane after hot press molding and excellent tunability in emboss processing.SOLUTION: A resin composition for a decorative plate contains a diallyl phthalate resin, an unsaturated polyester resin, and aluminum hydroxide. The unsaturated polyester resin has a number average molecular weight of 500-2,800. The aluminum hydroxide has an average particle diameter of 3 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resin composition for decorative boards, a decorative sheet, and a decorative board. More specifically, the present invention relates to a resin composition for decorative boards, a decorative sheet using the resin composition for decorative boards, and a decorative board including the decorative sheet. [Background technology]

[0002] Conventionally, decorative boards have been used on the surfaces of tables, counters, walls, floors, etc., by laminating a resin-impregnated layer, such as impregnated paper obtained by impregnating a paper base material such as titanium paper with a thermosetting resin such as diallyl phthalate resin, on a base material, and then superimposing a mirror plate on the resin-impregnated layer and thermo-pressing the resin to harden the thermosetting resin. The surface of the decorative board may be subjected to high gloss treatment, low gloss treatment (matte treatment), embossing, etc., for the purpose of imparting a sense of luxury or a desired pattern. Among them, decorative boards using diallyl phthalate resins are known as decorative boards having weather resistance, natural texture, heat resistance, chemical resistance, and dimensional stability.

[0003] By overlapping a substrate having an uneven surface on the surface of the decorative plate, an uneven surface is formed on the surface of the resin-impregnated layer, and embossing can be performed. If the resin-impregnated layer contains a coloring pigment, the convex parts of the resin-impregnated layer become dark in color when embossed, and the concave parts become light in color, and the color depth (harmonicity) according to the thickness of the resin-impregnated layer is expressed (for example, see Patent Document 1).

[0004] In addition, from the viewpoint of disaster prevention, decorative boards are sometimes required to be flame retardant or non-combustible. For the purpose of imparting flame retardancy or non-combustible properties to decorative boards, decorative boards are known in which a flame retardant such as aluminum hydroxide is blended into the resin impregnated layer (see, for example, Patent Documents 2 to 4). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 5-147050 [Patent Document 2] JP 2011-79870 A [Patent Document 3] JP 2009-234200 A [Patent Document 4] JP 2006-35839 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, if aluminum hydroxide is blended into the resin-impregnated layer in an amount sufficient to render it non-flammable, there is a problem in that the mirror plate that is overlaid on the resin-impregnated layer will stick to the resin-impregnated layer during thermocompression molding to form the decorative board, making it difficult to release the mirror plate.

[0007] Furthermore, when aluminum hydroxide was added to a resin-impregnated layer containing a coloring pigment and embossed, the color depth (harmonicity) corresponding to the thickness of the resin-impregnated layer was not always achieved.

[0008] Therefore, the object of the present invention is to provide a resin composition for decorative panels which can be used to obtain a decorative panel having non-flammable properties, which satisfies at least one of the following: excellent release properties from a mirror-finished panel after thermo-compression molding, and excellent synchronization when embossed. [Means for solving the problem]

[0009] As a result of intensive research to achieve the above object, the present inventors have found that by using an unsaturated polyester resin having a number average molecular weight within a specific range in a resin composition for decorative boards containing a diallyl phthalate resin and an unsaturated polyester resin, and blending aluminum hydroxide having an average particle size within a specific range, a decorative board having non-combustibility and at least one of excellent releasability from a mirror plate after thermo-compression molding and excellent synchronization when embossed can be obtained. The present invention was completed based on these findings.

[0010] That is, the present invention provides a resin composition for decorative panels, comprising a diallyl phthalate resin, an unsaturated polyester resin, and aluminum hydroxide, wherein the unsaturated polyester resin has a number average molecular weight of 500 to 2800, and the aluminum hydroxide has an average particle size of 3 μm or less.

[0011] The mass ratio of the diallyl phthalate resin to the unsaturated polyester resin (the former:the latter) is preferably 20:80 to 90:10.

[0012] The resin composition for decorative boards preferably has a viscosity of 100 to 800 mPa·s in an acetone solution having a solid content of 50% by mass at 20° C. (rotation speed: 6 rpm).

[0013] The resin composition for decorative plates may contain a coloring pigment.

[0014] The resin composition for decorative boards may contain magnesium hydroxide.

[0015] The content of aluminum hydroxide is preferably 5 to 90 parts by mass per 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin.

[0016] The present invention also provides a decorative sheet comprising an impregnated base material and a resin-impregnated layer containing a thermosetting resin composition impregnated into the impregnated base material, wherein the thermosetting resin composition is the resin composition for decorative panels according to any one of claims 1 to 6 or a cured product thereof.

[0017] The resin-impregnated layer preferably has the resin composition for decorative panels on the surface that will become the mirror plate side during thermo-compression molding.

[0018] The decorative sheet may have an embossed shape on the surface of the resin-impregnated layer.

[0019] The present invention provides a decorative board comprising a substrate and the decorative sheet described above provided on at least one surface of the substrate.

[0020] The resin-impregnated layer may have an embossed shape on the surface opposite to the substrate. Effect of the Invention

[0021] According to the resin composition for decorative panels of the present invention, it is possible to obtain a decorative panel having non-flammability, which satisfies at least one of the following: excellent release properties from a mirror-finished panel after thermocompression molding, and excellent synchronization when embossed. [Brief description of the drawings]

[0022] [Figure 1] 1 is a cross-sectional view showing one embodiment of a decorative board using the decorative board resin composition of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing another embodiment of a decorative board using the decorative board resin composition of the present invention. [Diagram 3] 3A to 3C are diagrams showing an embodiment of a method for manufacturing the decorative board shown in FIG. 2. [Figure 4] 1A to 1C are diagrams showing an embodiment of a method for producing a decorative board having an embossed shape on the surface of a resin-impregnated layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [Resin composition for decorative panels] The resin composition for decorative boards of the present invention contains at least a diallyl phthalate resin, an unsaturated polyester resin, and aluminum hydroxide.

[0024] The diallyl phthalate resin is a prepolymer having an allyl group in the molecule, and is a resin having thermosetting properties (thermosetting resin).

[0025] The diallyl phthalate resin contains at least a constituent unit derived from a diallyl phthalate monomer. Examples of the diallyl phthalate monomer include diallyl orthophthalate, diallyl isophthalate, and diallyl terephthalate. The diallyl phthalate monomer may be used alone or in combination of two or more. The diallyl phthalate resin may be used alone or in combination of two or more. The weight average molecular weight of the diallyl phthalate resin measured by GPC method is preferably 10,000 to 50,000.

[0026] The unsaturated polyester resin may be in a liquid state or a solid state at room temperature. Only one type of unsaturated polyester resin may be used, or two or more types of unsaturated polyester resins may be used.

[0027] The unsaturated polyester resin may be a compound containing a structural unit derived from a polybasic unsaturated acid and a structural unit derived from a polyhydric alcohol.The unsaturated polyester resin may further contain a structural unit derived from a polybasic saturated acid.The unsaturated acid, the saturated acid, and the polyhydric alcohol may each be used in one kind or in two or more kinds.

[0028] Examples of the polybasic unsaturated acid include maleic acid, fumaric acid, itaconic acid, and phthalic acid monomers (orthophthalic acid, isophthalic acid, and terephthalic acid). The unsaturated acid preferably contains a phthalic acid monomer. It is also preferable to contain maleic acid.

[0029] Examples of the polyhydric alcohol component include ethylene glycol, propylene glycol, neopentyl glycol, diethylene glycol, and hydrogenated bisphenol A. The polyhydric alcohol component preferably contains propylene glycol. From the viewpoint of achieving superior releasability from the mirror plate, the polyhydric alcohol component preferably contains ethylene glycol and / or hydrogenated bisphenol A.

[0030] In addition, the unsaturated polyester resin may be an air-curable unsaturated polyester resin, for example, a polyester resin containing a structural unit derived from an aliphatic cyclic unsaturated acid such as tetrahydrophthalic acid, 3,6-endomethylenetetrahydrophthalic acid, or methyl-3,6-endomethylenetetrahydrophthalic acid as the unsaturated acid, and a structural unit derived from allyl glycidyl ether as the polyhydric alcohol.

[0031] The number average molecular weight (Mn) of the unsaturated polyester resin is 500 to 2800, preferably 800 to 2200. When the number average molecular weight is 500 or more, the fluidity of the resin composition can be maintained, and the impregnation into the impregnated substrate is excellent. When the number average molecular weight is 2800 or less, it is presumed that the number of bonds with the diallyl phthalate resin increases after thermal curing, and the releasability, clearness, and glossiness of the mirror plate are good. In addition, the fluidity of the resin composition is high when a pressing plate having an uneven shape is superimposed on the resin impregnated layer, and the curing speed is relatively slow, which promotes the movement of the color pigment and provides excellent synchronization. The number average molecular weight is more preferably 800 to 1500 from the viewpoint of more excellent releasability, clearness, and glossiness of the mirror plate. In addition, the number average molecular weight is more preferably 1600 to 2200 from the viewpoint of more promoting the flow of the color pigment when embossing is performed, and providing excellent synchronization. The number average molecular weight is a value obtained by GPC measurement.

[0032] The weight average molecular weight (Mw) of the unsaturated polyester resin is not particularly limited, but is preferably 2500 to 7000, more preferably 3500 to 5500. When the weight average molecular weight is 2500 or more, the fluidity of the resin composition can be maintained, and the impregnation into the impregnated substrate is more excellent. When the weight average molecular weight is 7000 or less, it is presumed that the number of bonds with the diallyl phthalate resin increases after thermal curing, and the releasability, clarity of image, and glossiness with respect to the mirror plate are better. In addition, the fluidity of the resin composition when a pressing plate having an uneven shape is high when the resin impregnated layer is superimposed, and the curing speed is relatively slow, which promotes the movement of the color pigment and tends to improve the synchronization. The weight average molecular weight is a value obtained by GPC measurement.

[0033] The molecular weight dispersity (Mw / Mn) of the unsaturated polyester resin is not particularly limited, but is preferably from 1.5 to 4.5, and more preferably from 2.0 to 4.0.

[0034] The acid value of the unsaturated polyester resin is not particularly limited, but is preferably 5 to 30 KOH mg / g, and more preferably 10 to 25 KOH mg / g.

[0035] The mass ratio (former:latter) of the diallyl phthalate resin to the unsaturated polyester resin in the resin composition for decorative board is preferably 20:80 to 90:10, more preferably 30:70 to 70:30. When the mass ratio is 30:70 or more, the gloss, alkali resistance, and releasability from a mirror plate of the decorative board tend to be more excellent. From the viewpoint of more excellent releasability from a mirror plate, sharpness, and gloss, the mass ratio is more preferably 51:49 to 70:30, particularly preferably 52:48 to 60:40. Moreover, from the viewpoint of more excellent non-flammability, the mass ratio is more preferably 30:70 to 40:60.

[0036] The total content of the diallyl phthalate resin and the unsaturated polyester resin in the resin composition for decorative board is preferably 20 to 90% by mass, more preferably 30 to 85% by mass, and even more preferably 40 to 80% by mass, based on the total amount (100% by mass) of the resin composition for decorative board. If the content is 20% by mass or more, a resin-impregnated layer having sufficient strength can be obtained by hot and pressure molding.

[0037] The resin composition for decorative board may contain a monomer constituting a diallyl phthalate resin or an unsaturated polyester resin, or an oligomer of the monomer (e.g., a polymer of two or three units). For example, the resin composition may contain the diallyl phthalate monomer, which is a constituent unit of the diallyl phthalate resin.

[0038] The resin composition for decorative boards contains aluminum hydroxide. By containing aluminum hydroxide, the decorative board has non-flammability. The shape of the aluminum hydroxide is not particularly limited, and examples thereof include cylindrical, needle-like, and spherical shapes. Only one type of aluminum hydroxide may be used, or two or more types may be used.

[0039] The average particle size of the aluminum hydroxide in the resin composition for decorative board is 3 μm or less, preferably 2 μm or less, more preferably 1.5 μm or less. By having the average particle size of 3 μm or less, the flow of the resin composition during thermocompression molding is suppressed, the resin film thickness can be ensured to be sufficiently thick, and the mold release property against the mirror plate is excellent, the transparency is high, and the appearance is excellent. In addition, when a pressing plate having an uneven shape is superimposed on the resin impregnated layer, it is presumed that the movement of the coloring pigment is not hindered in the part where the thickness of the resin composition is thin, and the synchronization is excellent. Furthermore, the transparency is also excellent. The average particle size is, for example, 0.2 μm or more, and may be 0.3 μm or more, or 0.5 μm or more. The average particle size can be measured by a laser diffraction / scattering particle size distribution measuring device, or can be measured from an electron microscope photograph, and can also be calculated from the electron microscope photograph using an image processing device. Usually, the average particle size is generally measured by a laser diffraction method.

[0040] The aluminum hydroxide may be surface-treated. By subjecting the aluminum hydroxide to surface treatment, the aluminum hydroxide can be better dispersed in the resin composition for decorative boards. Examples of the surface treatment compound include a silane coupling agent and a titanium coupling agent.

[0041] The above-mentioned silane coupling agent can be an organic silicon compound having two or three alkoxy groups in the molecule.The above-mentioned organic silicon compound can be, for example, vinyl silanes such as vinyl triethoxy silane, vinyl trimethoxy silane, vinyl tris (β-methoxy ethoxy) silane; epoxy silanes such as β- (3,4-epoxy cyclohexyl) ethyl trimethoxy silane, γ-glycidoxy propyl trimethoxy silane; amino silanes such as γ-amino propyl triethoxy silane, N-β- (amino ethyl) -γ-amino propyl methyl dimethoxy silane; γ-mercapto propyl trimethoxy silane; γ-chloro propyl trimethoxy silane.

[0042] The content of aluminum hydroxide is preferably 5 to 90 parts by mass per 100 parts by mass of the diallyl phthalate resin and the unsaturated polyester resin in total. 5 When the content is 100 parts by mass or more, the non-combustibility and the image clarity are excellent. From the viewpoint of obtaining better non-combustibility and image clarity while ensuring releasability from the mirror plate, the content is more preferably 20 to 80 parts by mass, and even more preferably 30 to 70 parts by mass. From the viewpoint of obtaining better synchronization when embossing is performed, the content is more preferably 7 to 50 parts by mass, and even more preferably 10 to 40 parts by mass.

[0043] The resin composition for decorative board may contain a crosslinking agent for crosslinking the diallyl phthalate resin or the unsaturated polyester resin. The use of the crosslinking agent can improve the hardness of the resin-impregnated layer after heat curing, and the releasability, image clarity, and glossiness are improved. Examples of the crosslinking agent include polyfunctional compounds such as polyfunctional monomers having at least two polymerizable functional groups having unsaturated carbon-carbon double bonds, such as (meth)acryloyl groups or vinyl groups, and polymers of the polyfunctional monomers. The crosslinking agents may be used alone or in combination.

[0044] Examples of the polyfunctional monomer include polyfunctional (meth)acrylates such as hexanediol di(meth)acrylate, dodecanediol di(meth)acrylate, butanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, allyl (meth)acrylate, vinyl (meth)acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di(meth)acrylate, and hexyl di(meth)acrylate. Of the polyfunctional compounds, poly(meth)acrylates of dipentaerythritol having three or more (meth)acryloyl groups in the molecule are preferred.

[0045] The content of the crosslinking agent is preferably 0.6 to 20 parts by mass, more preferably 1 to 16 parts by mass, based on 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin. When the content is within the above range, the hardness of the resin-impregnated layer after heat curing becomes more appropriate, and the releasability becomes more appropriate. In addition, the image sharpness and glossiness are further improved, resulting in a better appearance.

[0046] The above-mentioned resin composition for decorative boards preferably contains a polymerization initiator (curing agent). By using the above-mentioned polymerization initiator, the curing speed becomes faster than the polymerization of diallyl phthalate resin or unsaturated polyester resin alone, and a resin-impregnated layer having a sufficient degree of curing can be obtained in a short time by hot-press molding. Examples of the above-mentioned polymerization initiator include organic peroxide-based curing agents such as benzoyl peroxide, tertiary butyl perbenzoate, methyl ethyl ketone peroxide, and dicumyl peroxide.

[0047] The content of the polymerization initiator is preferably 0.1 to 10 parts by mass, and more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin.

[0048] The resin composition for decorative board may contain other components other than the above-mentioned components. The other components include thermosetting resins other than diallyl phthalate resins and unsaturated polyester resins, flame retardants other than aluminum hydroxide, curing catalysts, curing accelerators, polymerization inhibitors, release agents, fillers such as silica, plasticizers, dispersants, thickeners, viscosity adjusters, colorants (pigments, dyes, etc.), defoamers, preservatives, ultraviolet absorbers, depleting agents, antibacterial agents, leveling agents, silane coupling agents, etc. The other components may each be used alone or in combination of two or more.

[0049] In order to make the resin composition for decorative boards excellent in the synchronization when embossed, the resin composition for decorative boards preferably contains a coloring pigment. As the coloring pigment, known or conventional pigments can be used, among which pearl pigments are preferred. The content of the coloring pigment is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin.

[0050] Examples of flame retardants other than the aluminum hydroxide include metal oxides such as magnesium hydroxide. When the resin composition for decorative board is to have excellent synchronization when embossed, it is preferable to contain other flame retardants in addition to aluminum hydroxide in order to have excellent synchronization and sufficient non-flammability. On the other hand, when the release property from the mirror plate is to be improved or molding stability is important, it is preferable not to contain magnesium hydroxide (for example, 5 parts by mass or less per 100 parts by mass of the diallyl phthalate resin and the unsaturated polyester resin). The other flame retardants may be used alone or in combination of two or more.

[0051] The average particle size of the other flame retardants is preferably 4 μm or less, more preferably 3 μm or less, and more preferably 2 μm or less, from the viewpoint of improving synchronization without inhibiting the movement of the color pigment in the thin part of the resin composition when a pressing plate having an uneven shape is superimposed on the resin impregnated layer. The average particle size is, for example, 0.2 μm or more, and may be 0.3 μm or more, or 0.5 μm or more. The average particle size of the other flame retardants is determined by the same method as the average particle size of the aluminum hydroxide.

[0052] The content of the other flame retardants is appropriately set according to the content of all the flame retardants in the resin composition for decorative boards. The content of the flame retardants in the resin composition for decorative boards is preferably 10 to 90 parts by mass, more preferably 20 to 70 parts by mass, and even more preferably 30 to 60 parts by mass, based on 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin.

[0053] When the release agent is contained, the releasability from the mirror plate is improved. Examples of the release agent include a fluorine-based release agent, a silicone-based release agent, and a wax-based release agent. The release agent may be used alone or in combination of two or more kinds.

[0054] The content of the release agent is preferably 0.1 to 8 parts by mass, more preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin. When the content is 0.1 parts by mass or more, the release property from the mirror plate is improved. When the content is 8 parts by mass or less, the adhesion between the resin-impregnated layer and the substrate in the decorative board is improved.

[0055] When the polymerization inhibitor is included, the reaction rate of the diallyl phthalate resin and the unsaturated polyester resin can be adjusted, and molding stability can be improved. As the polymerization inhibitor, known or conventional ones can be used, for example, hydroquinones such as hydroquinone, methyl hydroquinone, p-tert-butyl catechol, and mono-tert-butyl hydroquinone; phenols such as hydroquinone monomethyl ether and di-tert-butyl-p-cresol; quinones such as benzoquinone, p-benzoquinone, naphthoquinone, and p-toluquinone; copper salts such as di-tert-butyl hydroxytoluene, 2,6-di-tert-butyl-4-methylphenol, and copper naphthenate; and phenothiazine. The polymerization inhibitor may be used alone or in combination of two or more kinds.

[0056] The content of the polymerization inhibitor is preferably 0.005 to 0.5 parts by mass, more preferably 0.05 to 0.3 parts by mass, and even more preferably 0.8 to 0.15 parts by mass, based on 100 parts by mass of the total of the diallyl phthalate resin and the unsaturated polyester resin. When the content is within the above range, the molding stability of the decorative board is more excellent.

[0057] The viscosity (rotation speed: 6 rpm) of the resin composition for decorative board in an acetone solution having a solid content of 50% by mass at 20°C is preferably 110 to 800 mPa·s, more preferably 150 to 700 mPa·s. The viscosity (rotation speed: 60 rpm) of the resin composition for decorative board in an acetone solution having a solid content of 50% by mass at 20°C is preferably 30 to 200 mPa·s, more preferably 40 to 120 mPa·s. The above viscosity is a value measured using a B-type viscometer for a solution obtained by adding acetone to the resin composition for decorative board until the solid content concentration becomes 50% by mass.

[0058] The thixotropic index (TI) of the resin composition for decorative board in an acetone solution having a solid content of 50% by mass at 20°C is preferably 3 to 8, more preferably 4 to 7. When the TI is 3 or more, the resin composition has high thixotropy and is more excellent in impregnation into the impregnated substrate. When the TI is 8 or less, the resin composition has appropriate fluidity when impregnated into the impregnated substrate, and is more excellent in impregnation into the impregnated substrate. The TI is a value calculated based on the viscosity of the acetone solution having a solid content of 50% by mass at 20°C, by [viscosity (6 rpm) / viscosity (60 rpm)].

[0059] [Decorative sheet] The resin composition for decorative boards can be used to produce decorative sheets and decorative boards. The decorative sheets include decorative sheets that have a resin-impregnated layer containing an impregnated base material and a thermosetting resin composition impregnated into the impregnated base material, and the thermosetting resin composition is the resin composition for decorative boards or a cured product thereof.

[0060] The decorative board resin composition is a thermosetting resin composition. The thermosetting resin composition includes both a resin composition having thermosetting properties (thermosetting resin composition) and a composition containing a resin obtained by curing a thermosetting resin (such as a diallyl phthalate resin or an unsaturated polyester resin, which is a prepolymer) in the thermosetting resin composition (thermosetting resin composition). That is, the resin-impregnated layer includes a layer in which the thermosetting resin composition is impregnated into an impregnated substrate (a layer before thermosetting, a prepreg) and a layer in which the thermosetting resin in the composition is cured (a layer after thermosetting).

[0061] The resin-impregnated layer is a layer in which the resin composition for decorative boards or the cured product of the resin composition is impregnated into an impregnated substrate. The resin-impregnated layer may be a single layer or a multi-layer (laminate). The resin-impregnated layer may have a single layer of the resin composition for decorative boards, or may have a plurality of different layers of the resin composition for decorative boards (multi-laminate). In particular, since the resin composition for decorative boards of the present invention has excellent releasability against mirror-finished boards, it is preferable that the resin-impregnated layer has the resin composition for decorative boards at least on the surface that becomes the mirror-finished board side during thermocompression molding.

[0062] The impregnated substrate is not particularly limited as long as it can be impregnated with the resin composition for decorative board, and examples thereof include impregnated paper cloth such as titanium paper, tissue paper, reinforced paper, kraft paper, and cellulose paper; woven or nonwoven fabric such as polyester, rayon, acrylic, and vinylon. The impregnated paper cloth may be printed. The impregnated substrate may be single-layered or multi-layered.

[0063] The amount of the thermosetting resin composition impregnated into the impregnated substrate is 10 to 500 g / m per area of ​​the impregnated substrate. 2 is preferable, and more preferably 100 to 300 g / m 2 The above impregnation amount is 10g / m 2 When the amount of impregnation is 500 g / m or more, the amount of impregnation is sufficient and the releasability from the mirror plate is excellent. 2 If it is less than this, the cost can be reduced.

[0064] The thickness of the resin-impregnated layer is not particularly limited, but is, for example, 10 to 200 μm, and preferably 20 to 100 μm. If the thickness is 10 μm or more, the occurrence of defects such as poor flow during thermocompression molding can be suppressed. If the thickness is 200 μm or less, warping of the molded product due to resin shrinkage can be suppressed.

[0065] The resin-impregnated layer can be produced by a known or conventional method, and can be produced, for example, as follows. First, a resin composition for decorative boards, which is a thermosetting composition, is prepared. The resin composition for decorative boards is obtained by mixing a diallyl phthalate resin, an unsaturated polyester resin, and aluminum hydroxide with the above-mentioned various components as necessary. When the resin composition for decorative boards is low in viscosity, the impregnated substrate can be immersed in the resin composition bath for decorative boards to be impregnated. When the resin composition for decorative boards is a high-viscosity liquid or solid, the resin composition for decorative boards is diluted or dissolved in an appropriate solvent, such as an organic solvent such as acetone, toluene, or methyl ethyl ketone, to obtain a resin liquid with a suitable viscosity, and the impregnated substrate is immersed in the resin liquid, and then dried to volatilize the solvent. The impregnation temperature is, for example, 10 to 35°C, and preferably 20 to 30°C. Although the method of immersing the impregnated substrate in the bath of the resin composition for decorative boards has been described, the impregnation may be performed by applying the resin composition for decorative boards to the surface of the impregnated substrate and leaving it to soak in. When the thermosetting resin composition is a cured product of the resin composition for decorative boards, the resin composition for decorative boards can be cured and produced by hot pressing using the method described in detail later in the method for producing decorative boards.

[0066] [Decorative board] The decorative sheet can be used to produce a decorative board. The decorative board includes, for example, a substrate and the decorative sheet provided on one side of the substrate. More specifically, the decorative board includes at least a laminated structure of a substrate and a decorative sheet including a resin-impregnated layer in which the resin composition for decorative board is impregnated into the substrate.

[0067] In the decorative board, the surface of the resin-impregnated layer (i.e., the surface opposite to the substrate) may have an embossed shape. A decorative board having a resin-impregnated layer produced using the resin composition for decorative boards of the present invention exhibits a harmonious property according to the thickness of the resin-impregnated layer when embossed.

[0068] The decorative board may have other layers in addition to the above-mentioned layers. Examples of the other layers include a primer layer for improving the adhesion between the resin-impregnated layer and the substrate, a core layer for imparting shape stability to the decorative board, and a protective film for protecting the surface of the resin-impregnated layer. It is preferable that the surface of the resin-impregnated layer that is the side that is overlapped with the mirror plate during thermo-compression molding does not have a release layer.

[0069] One embodiment of the decorative board is shown in Figures 1 and 2. The decorative board 10 shown in Figure 1 comprises a substrate 1, a resin-impregnated layer 2, and a protective film 3. The resin-impregnated layer 2 is a layer (prepreg) in which an impregnated substrate is impregnated with a resin composition for decorative boards, which is a thermosetting resin composition, and is formed on one surface of the substrate 1. The protective film 3 is formed on the surface of the resin-impregnated layer 2 opposite the substrate 1. The decorative board 10' shown in Figure 2 comprises a substrate 1, a resin-impregnated layer 2', and a protective film 3. The resin-impregnated layer 2' is a layer in which an impregnated substrate is impregnated with a cured product of the resin composition for decorative boards, and is obtained by thermally curing the resin-impregnated layer 2.

[0070] The substrate may be a known or conventional substrate used for decorative boards. The substrate may be an organic substrate or an inorganic substrate. The organic substrate may be, for example, a wood substrate such as a single board, a plywood, a laminated lumber, a particle board, a medium density fiberboard (MDF), a high moisture fiberboard, or a kenaf board; a fibrous substrate such as a paperboard, a woven fabric, a nonwoven fabric, a resin-impregnated paper, or a resin-impregnated cloth; or a synthetic resin substrate such as an acrylic resin board, a styrene resin board, an ABS resin board, a polycarbonate resin board, a nylon resin board, a polystyrene resin board, a polypropylene resin board, a polyester resin board, or a glass fiber reinforced plastic board. Examples of the inorganic substrate include metal substrates such as aluminum plates, stainless steel plates, duralumin plates, steel plates, and brass plates; inorganic substrates such as magnesium oxide plates, aluminum hydroxide plates, aluminum oxide plates, silicon oxide plates, titanium oxide plates, magnesium chloride plates, calcium silicate plates, volcanic glassy material plates, gypsum (calcium sulfate) plates, slag gypsum plates, limestone (calcium carbonate) plates, wood wool cement plates, slag cement plates, lightweight aerated concrete plates, and glass fiber reinforced concrete plates. The substrate may be a single layer or a laminate of the same or different layers. The substrate may be subjected to an easy-adhesion treatment such as a sealer treatment or a primer treatment to improve adhesion to the resin-impregnated layer.

[0071] The thickness of the substrate is not particularly limited, but is, for example, 2 to 50 mm, and preferably 3 to 30 mm. If the thickness is 2 mm or more, the substrate has sufficient strength and is less likely to break. If the thickness is 50 mm or less, the substrate is lightweight and easy to handle.

[0072] As the protective film, a known or conventional film used for decorative panels can be used, for example, a film obtained by subjecting a plastic film such as a polyethylene terephthalate film (PET film), a polypropylene film, or a polybutylene terephthalate film to a release treatment, a low-adhesion film, etc. The protective film is peeled off when the decorative panel is used.

[0073] The Gd value of the surface of the resin-impregnated layer (the surface opposite to the substrate) is not particularly limited, but is preferably 0.2 or more, more preferably 0.3 or more. When the Gd value is 0.2 or more, the decorative sheet has better image clarity.

[0074] The 20° gloss value (JIS Z8741) of the surface of the resin-impregnated layer (the surface opposite to the substrate) is not particularly limited, but is preferably at least 50, more preferably at least 60, and even more preferably at least 70. When the gloss value is at least 50, the decorative board has better gloss.

[0075] [Manufacturing method of decorative panels] An embodiment of the manufacturing method of the above-mentioned decorative board will be described with reference to FIG. 3. First, as described above, the thermosetting resin composition for decorative boards, which is prepared by diluting or dissolving with a solvent as necessary, is impregnated into an impregnated substrate, and then, as necessary, the solvent is evaporated by drying to prepare a resin-impregnated layer 2 in which the thermosetting resin composition for decorative boards is impregnated into the impregnated substrate. Next, as necessary, the resin-impregnated layer 2 and a releasable substrate such as a polyethylene film are laminated together to obtain a decorative sheet. The lamination can be performed, for example, by laminating using a pressure roll.

[0076] Next, the decorative sheet is placed on the substrate 1 so that the resin-impregnated layer 2 faces the substrate 1, and if a releasable substrate is present, the releasable substrate is peeled off, and the mirror plate 4 is superimposed on the resin-impregnated layer 2 to obtain a laminate in which the decorative sheet 10 and the mirror plate 4 are laminated. The surface of the mirror plate 4 facing the resin-impregnated layer 2 has a shape for transferring a design to the resin-impregnated layer as necessary.

[0077] Next, a press is used to apply heat and pressure from above and below the laminate including the decorative plate 10 to perform thermocompression molding, hardening the resin-impregnated layer 2 to form a thermoset resin-impregnated layer 2', and obtaining a laminate in which the decorative plate 10' and the mirror plate 4 are laminated. As described above, the thermocompression molding method is preferably a laminate thermocompression molding method, in which the resin-impregnated layer 2 and the substrate 1 are overlapped and placed in a mold, and then heated and pressurized for hardening. The thermocompression molding is preferably performed at a pressure of, for example, 10 to 25 kgf / cm.2 The heating can be preferably performed under conditions of a temperature of 120 to 190° C. and a time of 30 seconds to 15 minutes.

[0078] The laminate obtained after thermocompression molding includes a decorative board 10' in which a substrate 1 and a thermoset resin-impregnated layer 2' provided on the substrate 1 are laminated. The mirror plate 4 is then removed to obtain the decorative board 10'. In the decorative board, the resin-impregnated layer formed from the resin composition for decorative board has excellent releasability from the mirror plate, so that the mirror plate 4 can be easily removed.

[0079] When preparing a decorative board 10' having an embossed shape on the surface of the resin-impregnated layer 2', a pressing plate 5 having an uneven shape on the surface facing the resin-impregnated layer 2 is used instead of the mirror plate 4. Then, as shown in FIG. 4, when the pressing plate 5 is superimposed on the resin-impregnated layer 2, an uneven shape corresponding to the uneven shape is formed on the surface of the resin-impregnated layer 2. That is, the resin-impregnated layer 2 has a thick film portion 2a and a thin film portion 2b. When an uneven shape is formed on the surface of the resin-impregnated layer 2, a high pressure is applied to the area that becomes the thin film portion 2b compared to the area that becomes the thick film portion 2a. When the resin-impregnated layer 2 contains a color pigment, the color pigment flows from the area that becomes the thin film portion 2b to the area that becomes the thick film portion 2a when pressure is applied. At this time, the flow of the color pigment is not hindered due to the small average particle size of the aluminum hydroxide, and it can flow smoothly. As a result, in the resin-impregnated layer 2', the amount of the color pigment per unit area in the thick film portion 2a becomes greater than the amount in the thin film portion 2b, and synchronization is obtained. Thereafter, the laminate is subjected to heat and pressure molding using a press to obtain a decorative board 10' having an embossed pattern on the surface of the resin-impregnated layer 2'.

[0080] A protective film such as a PET film may then be laminated onto the surface of the resin-impregnated layer 2' of the decorative board 10'. In this manner, the above-mentioned decorative board can be manufactured.

[0081] As described above, the decorative board having a resin-impregnated layer obtained by using the resin composition for decorative boards of the present invention has excellent non-flammability and excellent releasability to the mirror plate after thermo-press molding because it contains aluminum hydroxide having an average particle size within a specific range. Therefore, there is no need to provide a separate release layer between the resin-impregnated layer and the mirror plate during thermo-press molding. And, because the average particle size of the aluminum hydroxide is within a specific range, the flow of the resin composition during thermo-press molding is suppressed, and the resin film thickness can be ensured to be sufficiently thick, and the obtained decorative board has excellent clarity and gloss, high transparency, and excellent appearance. In addition, when a resin-impregnated layer is prepared by blending a coloring pigment into the resin composition for decorative boards and the surface of the resin-impregnated layer is embossed, a synchronization according to the thickness of the resin-impregnated layer is expressed. EXAMPLES

[0082] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0083] <Decorative board with excellent release properties> Example 1 A resin composition solution was prepared by dissolving 56 parts by mass of diallyl orthophthalate prepolymer (viscosity (30°C) of 96.5 mPa·s in a 50% by mass solution in methyl ethyl ketone, manufactured by Osaka Soda Co., Ltd.), 43 parts by mass of unsaturated polyester (product name "TH-2510", number average molecular weight 1291, weight average molecular weight 4404, molecular weight dispersity 3.41, acid value 12.8 KOHmg / g, manufactured by DIC Material Co., Ltd.), 14 parts by mass of dipentaerythritol hexaacrylate, 50 parts by mass of aluminum hydroxide (product name "BF013STM", average particle size 1 μm, surface-treated, manufactured by Nippon Light Metal Co., Ltd.), 4 parts by mass of benzoyl peroxide, 3 parts by mass of an internal release agent (product name "Zereck UN", manufactured by DuPont), 0.2 parts by mass of hydroquinone (polymerization inhibitor), and 0.1 parts by mass of an antifoaming agent in 100 parts by mass of acetone. A resin composition solution was prepared by dissolving 60 g / m 2 After impregnating a printed pattern paper of 160 g / m with the resin composition, the paper was heated in a hot air circulating oven at 105° C. for 90 seconds to volatilize the solvent, and the resin composition was dried to a density of 160 g / m2 A decorative sheet made of impregnated paper (amount of impregnation per 100 parts by mass of printed pattern paper: 167 parts by mass) was obtained.

[0084] A base material (product name "Dailite", manufactured by Daiken Corporation, thickness 3 mm, non-combustible material) was placed on the circulating plate, and the decorative sheet was placed on the base material so that the impregnated paper was in contact with the base material. Then, using a press machine, pressure was applied so that the hot plate with the mirror plate set was on the impregnated paper side and the other hot plate was on the circulating plate side, and heat was applied to perform thermo-compression molding. The thermo-compression molding was performed at a temperature of 160°C and a pressure of 16 kgf / cm. 2 After that, the pressure was released, and the laminate of the transfer plate, the base material, and the decorative sheet was taken out of the press and cooled to room temperature to obtain a decorative plate.

[0085] Example 2 A decorative sheet and a decorative board were produced in the same manner as in Example 1, except that the amount of hydroquinone was changed to 0.1 parts by mass.

[0086] Comparative Example 1 A decorative sheet and a decorative board were produced in the same manner as in Example 1, except that 60 parts by mass of aluminum hydroxide (product name "BE043STM", average particle size 4 μm, surface-treated, manufactured by Nippon Light Metal Co., Ltd.) was used.

[0087] (evaluation) The decorative boards obtained in Examples 1 and 2 and Comparative Example 1 were evaluated as follows. The evaluation results are shown in Table 1.

[0088] (1) Mold releasability When producing each decorative panel obtained in the examples and comparative examples, the time it took for the molded product to fall from the mirror plate when the pressure was released after the molding time had elapsed was used as the basis for judging according to the following criteria. [Judgment criteria] ○ (Good): Peels off from the mirror plate when pressure is released, or falls off from the mirror plate shortly thereafter. × (Poor): It takes a long time for the mirror to fall off the plate.

[0089] (2) Molding stability The surface of the resin-impregnated layer of each of the decorative boards obtained in the Examples and Comparative Examples was visually observed and rated according to the following criteria. [Judgment criteria] ○ (Good): No flow problems such as pinholes occurred. △ (usable): slight flow problems such as pinholes have occurred. × (bad): A large amount of flow defects such as pinholes occurred.

[0090] (3) 20° gross The surface of the resin-impregnated layer of each of the decorative boards obtained in the Examples and Comparative Examples was measured using a gloss meter (product name "micro-TRI-gloss", manufactured by Gardner) according to the method specified in JIS Z8741.

[0091] (4) Gd value The surface of the resin-impregnated layer of each decorative panel obtained in the examples and comparative examples was measured for its distinctness measurement value (Gd value) using a portable clarity and gloss meter (product name "PGD-4", PGD meter, Japan Color Research Institute Foundation, manufactured by Tokyo Koden Co., Ltd.).

[0092] [Table 1]

[0093] As shown in Table 1, the decorative sheets obtained in Examples 1 and 2 were evaluated as having excellent releasability. Furthermore, since they contained a sufficient amount of aluminum hydroxide, they were evaluated as having noncombustibility, excellent molding stability, high 20° gloss and excellent luster, high Gd value and excellent image sharpness, and good appearance. On the other hand, when the average particle size of aluminum hydroxide was 4 μm (Comparative Example 1), the releasability was evaluated as being poor.

[0094] <Decorative board with embossed shape> Example 3 Diallyl orthophthalate prepolymer (50% by mass solution in methyl ethyl ketone, viscosity (30°C) 96.5 mPa·s, manufactured by Osaka Soda Co., Ltd.) 38 parts by mass, unsaturated polyester (product name "DH-2000B", number average molecular weight 1869, weight average molecular weight 4846, molecular weight dispersity 2.59, acid value 21.1 KOHmg / g, manufactured by DIC Material Co., Ltd.) 81 parts by mass, dipentaerythritol hexaacrylate 5 parts by mass, aluminum hydroxide (product name "BF013STM", average particle size 1 μm, surface treated, manufactured by Nippon Light Metal Co., Ltd.) A resin composition solution was prepared by dissolving 37.5 parts by mass of dimethylformamide (manufactured by DuPont), 12.5 parts by mass of magnesium hydroxide (trade name "Magseeds N-6", average particle size 1.3 μm), 3 parts by mass of benzoyl peroxide, 1 part by mass of an internal release agent (trade name "Zelec UN", manufactured by DuPont), 0.05 parts by mass of hydroquinone (polymerization inhibitor), 3 parts by mass of finely powdered silica (trade name "Carplex", manufactured by Shionogi & Co., Ltd.), 3 parts by mass of pearl pigment (trade name "Iriodin 520", manufactured by Merck) and 0.15 parts by mass of an antifoaming agent in 100 parts by mass of acetone. The resin composition solution at 25° C. was added to 60 g / m 2 of the impregnation substrate. 2 After impregnating a dark-colored printed pattern paper of 160 g / m with the resin composition, the paper was heated in a hot air circulating oven at 105° C. for 90 seconds to volatilize the solvent, and the resin composition was dried to a thickness of 160 g / m 2 A decorative sheet made of impregnated paper (amount of impregnation per 100 parts by mass of printed pattern paper: 167 parts by mass) was obtained.

[0095] A substrate (product name "Dailite", manufactured by Daiken Corporation, thickness 3 mm, non-combustible material) was placed on the moving plate, and the decorative sheet was placed on the substrate so that the impregnated paper was in contact with the substrate. Then, using a press machine, pressure was applied so that the hot plate with the pressure plate set faced the impregnated paper side and the other hot plate faced the moving plate side, and heat was applied to perform thermo-compression molding. The surface of the pressure plate facing the impregnated paper had an uneven shape formed to give an embossed shape. The thermo-compression molding was performed at a temperature of 150°C and a pressure of 16 kgf / cm. 2 The pressure was then released, and the laminate of the transfer plate, the base material, and the decorative sheet was removed from the press and cooled to room temperature to obtain a decorative plate.

[0096] Example 4 80g / m as impregnated substrate 2 A decorative sheet and a decorative board were produced in the same manner as in Example 3, except that white paper of the above was used.

[0097] Example 5 A decorative sheet and a decorative board were produced in the same manner as in Example 3, except that the aluminum hydroxide used was trade name "BF013" (average particle size 1 μm, no surface treatment, manufactured by Nippon Light Metal Co., Ltd.).

[0098] Example 6 80g / m as impregnated substrate 2 A decorative sheet and a decorative board were produced in the same manner as in Example 5, except that white paper of the above was used.

[0099] Comparative Example 2 A decorative sheet and a decorative board were produced in the same manner as in Example 3, except that the aluminum hydroxide used was "BE043STM" (average particle size 4 μm, surface-treated, manufactured by Nippon Light Metal Co., Ltd.).

[0100] Comparative Example 3 80g / m as impregnated substrate 2 A decorative sheet and a decorative board were produced in the same manner as in Comparative Example 2, except that white paper of the above was used.

[0101] (evaluation) The decorative boards obtained in Examples 3 to 6 and Comparative Examples 2 and 3 were evaluated as follows. The evaluation results are shown in Table 2.

[0102] (5) Synchrony The surface of the resin-impregnated layer of each of the decorative boards obtained in the Examples and Comparative Examples was visually observed and rated according to the following criteria. [Judgment criteria] ◯ (Good): There is a large difference in the shade of color between the recessed and protruding parts, and the color is clearly in harmony with the embossed shape. × (bad): The difference in color intensity between the recessed and protruding parts is small, and no harmony with the embossed shape is felt.

[0103] [Table 2]

[0104] As shown in Table 2, the decorative boards obtained in Examples 3 to 6 were evaluated as having excellent synchronization. On the other hand, when the average particle size of aluminum hydroxide was 4 μm (Comparative Examples 2 to 3), the synchronization was evaluated as being poor.

[0105] Example 7 A decorative sheet and a decorative board were produced in the same manner as in Example 3, except that the amount of impregnation was 183 parts by mass per 100 parts by mass of the printed pattern paper.

[0106] (6) Combustion test A combustion test was conducted on each of the decorative panels obtained in Examples 3 and 7 in accordance with ISO5660 "Cone Calorimeter Method." The combustion test was conducted twice for each decorative panel. As a result, the average value of the two combustion tests for the total heat generation amount 20 minutes after the start of heating was 6.5 MJ / m for Example 3. 2 , and Example 7 is 7.5 MJ / m 2 The total calorific value was 8MJ / m 2 From these results, it is recognized that the decorative boards of Examples 4 to 6, which have the same impregnation amount, also have non-combustibility.

[0107] The physical properties of the unsaturated polyester resins used in the examples and comparative examples and the viscosity of an acetone solution of each of the resulting resin compositions having a solid content of 50% by mass were evaluated as follows.

[0108] (7) Average molecular weight of unsaturated polyester resin The weight average molecular weight and number average molecular weight were measured by GPC using a standard polystyrene calibration curve under the following conditions. Equipment: Shimadzu Corporation Prominence-i, LC-2030 Column: Shodex LF-804 x 2, guard column S Shifting phase: THF Flow rate: 1.0ml / min Injection volume: 50μl Column temperature: 40℃

[0109] (8) Viscosity Acetone was added to the resin composition so that the solid content concentration became 50% by mass, and the resulting solution was measured at 20° C. using a Brookfield viscometer (product name "BM type viscometer", manufactured by Tokimec Co., Ltd.) with a No. 1 rotor at rotation speeds of 6 rpm and 60 rpm. The rotor was rotated for at least 30 seconds, and the value when the value stabilized was read and used as the viscosity. [Explanation of symbols]

[0110] 1 Base material 2 Resin-impregnated layer (before heat curing, prepreg) 2a Thick film part 2b Thin film part 2' Resin impregnated layer (heat cured) 3 Protective film 4 Mirror plate 5 Pressure plate 10,10' Veneer

Claims

1. A resin composition for decorative boards, comprising a diallyl phthalate-based resin, an unsaturated polyester-based resin, aluminum hydroxide, and a release agent; The unsaturated polyester resin has a number average molecular weight of 500 to 2800. The average particle size of the aluminum hydroxide is 0.2 μm to 3 μm. a mass ratio (the former:the latter) of the diallyl phthalate-based resin to the unsaturated polyester-based resin is 20:80 to 90:10; the content of the aluminum hydroxide is 30 to 70 parts by mass per 100 parts by mass of the diallyl phthalate resin and the unsaturated polyester resin in total, The resin composition for decorative boards is used for producing a decorative sheet, The decorative sheet includes a resin-impregnated layer including an impregnated base material and a thermosetting resin composition impregnated into the impregnated base material, the thermosetting resin composition being the resin composition for decorative panels or a cured product thereof; The resin-impregnated layer has the resin composition for decorative panels on a surface that will become a mirror plate side during thermo-compression molding.

2. The resin composition for decorative boards according to claim 1, wherein the viscosity of a 50% by mass solids solution of the resin composition for decorative boards at 20°C (rotation speed: 6 rpm) is 100 to 800 mPa·s.

3. 3. The resin composition for decorative panels according to claim 1, further comprising a coloring pigment.

4. The resin composition for decorative panels according to any one of claims 1 to 3, further comprising magnesium hydroxide.

5. The present invention provides a resin-impregnated layer comprising an impregnated base material and a thermosetting resin composition impregnated into the impregnated base material, The decorative sheet, wherein the thermosetting resin composition is the resin composition for decorative panels according to any one of claims 1 to 4 or a cured product thereof.

6. A decorative sheet comprising an impregnated base material and a resin-impregnated layer comprising a thermosetting resin composition impregnated into the impregnated base material, The thermosetting resin composition is a resin composition for decorative boards or a cured product thereof, The resin composition for decorative boards contains a diallyl phthalate-based resin, an unsaturated polyester-based resin, aluminum hydroxide, and a release agent, The unsaturated polyester resin has a number average molecular weight of 500 to 2800. The average particle size of the aluminum hydroxide is 0.2 μm to 3 μm. a mass ratio (the former:the latter) of the diallyl phthalate-based resin to the unsaturated polyester-based resin is 20:80 to 90:10; the content of the aluminum hydroxide is 30 to 70 parts by mass per 100 parts by mass of the diallyl phthalate resin and the unsaturated polyester resin in total, The resin-impregnated layer is a decorative sheet having the resin composition for decorative panels on a surface that will become a mirror plate during thermo-compression molding.

7. 7. The decorative sheet according to claim 5, wherein the surface of said resin-impregnated layer has an embossed pattern.

8. A decorative board comprising a substrate and the decorative sheet according to any one of claims 5 to 7 provided on at least one surface of the substrate.

9. The decorative board according to claim 8 , wherein the resin-impregnated layer has an embossed shape on a surface opposite to the substrate.

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