JP2019123193A - Decorative sheet having magnetic layer - Google Patents

Abstract

To provide a decorative sheet capable of easily being constructed on a metallic wall surface.SOLUTION: A decorative sheet has a decorative sheet (7) with an adhesive including a decorative sheet layer (6) and an adhesive layer (5), and magnetic layers (8, 9), the decorative sheet layer (6) includes a decorative layer (1) and a mixed paper layer (2), the decorative layer (1) consists of a thermosetting resin impregnated decorative paper containing a thermosetting resin in a decorative paper, the mixed paper layer (2) consists of an impregnated paper containing a nitrogen-based flame retardant or a phosphorus nitrogen-based flame retardant or a thermosetting resin with magnesium silicate mixed paper having binding water as a substrate, and the magnetic layers (8, 9) are adhesion processed in a back surface side of the adhesive layer (5).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a decorative board having a magnetic layer on the back surface.

Heretofore, a melamine decorative board using a melamine resin-impregnated decorative paper, a phenol resin-impregnated paper or the like as a laminated material has been used for desks, tables, counters and the like.
In recent years, non-combustible decorative boards which impart non-combustibility to melamine decorative boards are known, and further, by providing a magnetic layer on the back surface of the melamine decorative boards, attachment to metal wall surfaces such as elevators and removal is easy. There is also known a decorative sheet that can be used and can be easily installed.

JP, 2013-180429, A

However, they can not be easily adhered to metal wall surfaces, and if an adhesive layer is provided on the back side of the decorative sheet with adhesive, the noncombustibility test of the Building Standard Law can not be cleared (total calorific value of 8 MJ / m ² or less) However, there is a problem that the shape can not be maintained and fails.

  The present invention has been studied in view of such a situation, and an adhesive layer is provided on the back surface of the decorative plate, a magnetic layer is further provided under the adhesive layer, and a decorative plate having a magnetic layer which can be easily applied to metal wall surfaces is provided. In the invention intended to be provided, a decorative sheet with an adhesive comprising a decorative board layer and an adhesive layer, and a magnetic layer, the decorative board layer comprising a decorative layer and a mixed paper layer, The decorative layer is made of a thermosetting resin-impregnated decorative paper containing a thermosetting resin as a decorative paper, and the mixed paper layer is a nitrogen-based flame retardant, or a phosphorus / nitrogen-based flame retardant, using magnesium silicate mixed paper having bound water. The above problem can be solved by using a decorative board having a magnetic layer comprising a flame retardant mixed paper impregnated with a flame retardant and having a magnetic layer on the back surface side of the pressure-sensitive adhesive layer.

  The decorative plate having the magnetic layer of the present invention is easy to process even if the plate thickness is thin, and can be simply applied to a metal wall surface by providing the magnetic layer. The sheet is excellent in balance, small in warpage, and excellent in nonflammability.

  Furthermore, the decorative plate usually comprises a decorative layer, a core layer, and optionally a surface layer, an intermediate layer, a backing layer, etc., and all use a resin impregnated paper containing a thermosetting resin or a thermoplastic resin. The mixed paper layer used in the invention is a magnesium silicate mixed paper having bound water as a base without impregnating a resin with a nitrogen based flame retardant, or a flame retardant mixed paper containing phosphorus and nitrogen based flame retardant impregnated paper, and the coated layer and core layer There was an unexpected effect such as excellent interlayer adhesion.

In addition, thermosetting resins and thermoplastic resins have thermal shrinkage that is specific to resins, and the size of the decorative board layer is larger in the case of using a paper impregnated with a flame retardant mixed paper than in the case of not impregnating a resin or impregnating a resin. It has the effect of being excellent in stability.

  Furthermore, the decorative board having the magnetic layer of the present invention has the ability to pass the flameproof performance test according to the Fire Service Law Construction Regulations (Article 4-3 application).

BRIEF DESCRIPTION OF THE DRAWINGS The structure sectional view of the decorative sheet with an adhesive in connection with this invention. BRIEF DESCRIPTION OF THE DRAWINGS The structure sectional view of the decorative board which has a magnetic layer of this invention. (Anisotropic magnetic sheet) Sectional drawing of a structure of the decorative board which has the other magnetic layer of this invention. (Isotropic magnetic sheet) A photograph showing translucency of Example 4. The photograph which shows the translucent property of the comparative example 4.

In the decorative layer according to the present invention, a resin liquid composed mainly of a thermosetting resin such as amino-formaldehyde resin, diallyl phthalate resin, unsaturated polyester resin, or a mixed resin thereof is used for thermosetting resin decorative panel A resin-impregnated decorative paper is used, which is impregnated in a decorative paper of 30 to 140 g / m < ² > such that the impregnation ratio shown by Equation 1 is 80 to 300%, and dried. Among the resins, particularly preferred is an aminoamino-formaldehyde resin which is excellent in heat resistance, abrasion resistance and the like. The amino-formaldehyde resin can be obtained by condensation of an amino compound such as melamine, urea, acetoguanamine or benzoguanamine with formaldehyde.
Particularly preferred is a melamine-formaldehyde resin which is excellent in water resistance, heat resistance, abrasion resistance, chemical resistance, stain resistance and light resistance.

  In the mixed paper layer according to the present invention, a flame retardant-impregnated paper obtained by impregnating a flame retardant with a heat-resistant fibrous base material and drying it is used. By using the flame retardant-impregnated paper, it is possible to obtain a well-balanced, yet suppress the warp of the finished decorative board.

The content of nitrogen flame retardant, phosphorus / nitrogen flame retardant or thermosetting resin in mixed paper layer (weight of flame retardant or thermosetting resin contained in mixed paper layer of unit area) is 9 to 90 g / m It is good to set it as ² . If it is this range, the curvature of a decorative board can be suppressed and it is excellent in flexibility. The content is a solid content value.

As a heat-resistant fibrous base material, a slurry containing a pulp and a silicate compound having binding water as a main component and added with an aggregation binder, a drug, an organic fiber, an inorganic fiber, a fixing agent, etc. A mixed paper of 60 to 400 g / m ² is used which is made by a mesh multi-tube type paper machine, a long mesh-yen mesh combination paper machine, an inclined paper machine or the like, dewatered and dried. The mixed paper thus obtained has self-extinguishing properties and can suppress the spread of flames. The pulp may be natural pulp such as wood pulp, cotton pulp, vegetable fiber pulp etc. In particular, chemical pulp obtained by chemically treating wood pulp having a short fiber length such as hardwood bleached kraft pulp, softwood kraft pulp etc. It has strength and is excellent in impregnation suitability and is preferred. Hardwood bleached kraft pulp and softwood kraft pulp may be used in combination or may be either bleached or unbleached.

As a silicate compound having bound water, hydrous magnesium silicate [Mg ₈ Si ₁₂ O ₃₀ (OH ₂ ) ₄ (OH) ₄ 6 to 8 H ₂ O] (sepiolite), hydrous magnesium silicate [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ) (talc), hydrous magnesium aluminum silicate [Mg ₅ Si ₈ O ₂ 0 (OH) ₂ (H ₂ O) ₄ .4 H ₂ O] (attapulgite), hydrous aluminum silicate [(Mg, Ce, Al) ₃ Examples include hydrous magnesium silicate compounds such as (Al, Si) ₄ O ₁₀ (OH) ₂ .4H ₂ O] (vermiculite). In particular, sepiolite is preferred because of its excellent flame resistance and water resistance. The mixing ratio of the silicate compound having bound water and the pulp is preferably 40 to 95% by weight, more preferably 55 to 85% by weight, of the content ratio of the silicate compound. If the amount is less than 40% by weight, the non-combustible performance tends to be deteriorated, and if it exceeds 95% by weight, the paper strength tends to be reduced.

  As a flame retardant, a phosphorus flame retardant, a nitrogen flame retardant, and a phosphorus and nitrogen flame retardant are used suitably. Examples of phosphorus-based flame retardants include phosphate ester, phosphorus-containing polyol, phosphorus-containing amine, melamine cyanurate as nitrogen-based flame retardant, triazine compound, guanidine compound, guanidine phosphate and phosphorus guanyl urea as phosphorus and nitrogen-based flame retardant Be Phosphorus and nitrogen based flame retardants are compounds that combine the functions of phosphorus based flame retardants and nitrogen based flame retardants and have both phosphorus atoms and nitrogen atoms in one molecule, and when exposed to high temperatures, phosphorus has a strong dehydration effect In this case, oxygen is shut off, nitrogen generates ammonia gas, etc., and oxygen can be shut off, so the heat insulation and flame retarding effect is improved and the prepreg is made to be difficult to burn.

  Although the reason why the interlaminar adhesion between the decorative layer and the core layer is excellent despite the impregnation with the flame retardant is not clear, the flame retardant and the thermosetting resin contained in the cosmetic layer, and the thermoplastic resin contained in the core layer Amino-formaldehyde resin-impregnated paper which is reacted with resin and firmly bonded, or the decorative layer is impregnated with amino-formaldehyde resin, dried, mixed paper layer with nitrogen flame retardant, phosphorus and nitrogen based flame retardant In the case of a flame retardant, the amino group contained in the decorative layer and the nitrogen contained in the mixed paper layer are deeply combined with the thermoplastic resin or the silane coupling agent or the flame retardant contained in the core layer. I think there is. It is usual to carry out the boiling resistance test of JIS K 6902 in order to judge the interlaminar adhesion, but in Comparative Example 2 which is not impregnated with a flame retardant, it is easy to delaminate by hand after hot-press molding and boiling resistance It was not necessary to do a sex test.

  For the core layer, one or more prepregs obtained by impregnating and drying a slurry containing a thermoplastic resin as a binder component and an endothermic metal hydroxide as an essential component in a fibrous base material are used.

  Examples of fibrous substrates include organic fiber substrates and inorganic fiber substrates. Examples of organic fiber substrates include polyethylene, polypropylene, vinylon, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyamide and polyester. And polyurethanes, modified products thereof, fibers made of various copolymers represented by ethylene-vinyl acetate copolymer and the like, and mixtures thereof.

Examples of the inorganic fiber substrate include non-woven fabrics and woven fabrics made of inorganic fibers such as glass fibers, rock wool and carbon fibers, and the basis weight of the inorganic fiber substrate is in the range of 10 to ²⁰⁰ g / m ² preferable. When an inorganic fiber base is used, the nonflammability of the decorative board is further improved as compared with the case where an organic fiber base is used. Among the inorganic fiber substrates, particularly when a glass fiber non-woven fabric is used, the warp of the finished decorative plate without a fiber direction is suppressed, and the heat resistance, the flame resistance and the impregnation of the slurry are further improved.

  An acrylic resin emulsion is suitably used as the thermoplastic resin as a binder component. In particular, it is more preferable to use an acrylic resin emulsion having a glass transition temperature (Tg) of −20 ° C. or higher, because the adhesion and the formability are improved. Among them, the use of an acrylic resin emulsion having an average particle diameter of 150 to 300 nm is more preferable because the binding strength of the core layer and the bending processability and smoothness of the decorative plate can be further improved. It can be inferred that the reason why the smoothness is improved is that the acrylic resin emulsion is fine particles. The average particle size is a value calculated based on scattered light detected at the time of laser irradiation using a laser light diffraction / scattering type particle size measuring device (ELS-8000 manufactured by Otsuka Electronics Co., Ltd.).

  It is desirable that the mixing ratio of the thermoplastic resin is 3 to 17% by weight in the slurry in solid content, and by being below the upper limit, the nonflammability is further improved and the synthetic resin oozes out during hot pressure molding Things are less likely to happen. Moreover, while being more than a minimum, while the adhesiveness of prepregs improves further, control of the amount of impregnation of the slurry to a fibrous base material becomes much easier.

The amount of the thermoplastic resin contained in the core layer (the weight of the thermoplastic resin contained in the core layer per unit area) is 10 to 100 g / m ² . By being 100 g / m < ² > or less, the nonflammability of a decorative board improves further. Moreover, when it manufactures a decorative board by hot press molding because it is 100 g / m < ² > or less, it becomes difficult to occur that a thermoplastic resin oozes out.

Moreover, when the amount of the thermoplastic resin which a core layer contains is 10 g / m < ² > or more, when manufacturing a core layer from a prepreg, the adhesiveness of prepregs improves further. Moreover, when making a fibrous base material impregnate a slurry and manufacturing a core layer because it is 10 g / m < ² > or more, the amount of impregnations of a slurry can be controlled much more easily.

  Endothermic metal hydroxides contain water of crystallization and decompose at high temperatures to release water. Since the reaction is an endothermic reaction, it has the effect of suppressing a temperature rise at the time of combustion, and improves the nonflammability of the decorative board of the present invention. As the endothermic metal hydroxide, for example, as described above, aluminum hydroxide, magnesium hydroxide, calcium hydroxide and the like can be mentioned, and in particular, aluminum hydroxide and magnesium hydroxide are suitably used. When the blending ratio of the endothermic metal hydroxide in the slurry is 20 to 95% by weight, it becomes a decorative board having good adhesion and incombustibility.

  The average particle size of the endothermic metal hydroxide can be, for example, in the range of 1 to 50 μm. The average particle diameter is an arithmetic average diameter calculated from a particle size distribution (volume distribution) detected by a laser diffraction / scattering method (microtrack method). When the average particle diameter of the endothermic metal hydroxide is within the above range, the dispersibility of the endothermic metal hydroxide in the slurry is improved, and the impregnation of the slurry into the fibrous base material is improved. . Moreover, the surface of a decorative board becomes a smooth finish.

The amount of the endothermic metal hydroxide contained in the core layer (the weight of the endothermic hydroxide contained in the core layer per unit area) is preferably in the range of 50 to 600 g / m ² . By being in this range, when manufacturing a core layer from pregreg, the adhesiveness of prepregs can be improved and the non-combustible performance of a decorative board can be improved.

  The slurry may further contain an inorganic filler other than the endothermic metal hydroxide, a silane coupling agent, a flame retardant, and the like.

  Examples of the inorganic filler include carbonates such as calcium carbonate, magnesium carbonate and zinc carbonate, silica, talc, fly ash and the like. The average particle size of the inorganic filler (arithmetic mean diameter calculated from particle size distribution (volume distribution) detected by laser diffraction / scattering method (microtrack method)) is, for example, in the range of 0.05 to 20 μm. be able to. In this case, the ability to impregnate the fibrous base material with the slurry is further improved.

  Among the inorganic fillers, in particular, carbonates such as calcium carbonate can be selected. In this case, the workability and the cuttability in the manufacturing process of the decorative plate are further improved. As calcium carbonate, ground calcium carbonate, light calcium carbonate (precipitable calcium carbonate), etc. can be used. The average particle size of calcium carbonate can be, for example, 0.05 to 10 μm, and more preferably 0.1 to 5 μm. By setting it as 0.05 micrometer or more, aggregation of calcium carbonate becomes difficult to occur in a slurry, and the impregnatability to the fibrous base material of a slurry improves. In addition, by setting the thickness to 10 μm or less, the surface of the decorative plate becomes smoother, and the appearance is improved.

  In addition, light calcium carbonate means calcium carbonate produced by calcinating limestone chemically, and heavy calcium carbonate means fine calcium carbonate produced by dry or wet grinding of white crystalline limestone.

  The blending ratio of the endothermic metal hydroxide in the total inorganic filler contained in the prepreg can be set to 30 to 100% by weight. Within this range, the non-combustibility and the cuttability of the decorative board and the decorative sheet with adhesive are further improved.

  In the decorative board according to the present invention, the slurry may contain a silane coupling agent. In this case, the weight increase rate becomes smaller in boiling resistance according to JIS K-6902 “Thermosetting resin high-pressure decorative board test method” than when the silane coupling agent is not contained, and the prepreg and the intermediate layer Adhesion is further improved. The blending ratio of the silane coupling agent is in the range of 0.1 to 10% by weight in terms of solids content in all components of the slurry.

  Examples of silane coupling agents include (meth) acryloyloxy group-containing silanes such as 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltrimethoxysilane, and the like. Vinyl group-containing silanes such as ethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, epoxy-containing silanes such as 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxy Styryl group-containing silanes such as silane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, etc. Amino group-containing silane, 3-mercaptopropyl trimethoxysilane, 3-mercaptopropyl triethoxysilane, mercapto group-containing silane such as 3-mercaptopropyl methyl dimethoxy silane. In particular, when an epoxy group-containing silane or an amino group-containing silane is used, the crosslink density in the prepreg is further improved.

The amount of the silane coupling agent contained in the core layer (the weight of the silane coupling agent contained in the core layer per unit area) is preferably in the range of 1 to ²⁰ g / m ² . By being in this range, the effect by the above-mentioned silane coupling agent becomes more remarkable.

The core layer can contain the same flame retardant as described above. It is preferable that the total nitrogen content in the flame retardant be 1 to 50% by weight. The blending ratio of the flame retardant is in the range of 0.1 to 15% by weight in terms of solid content in all components of the slurry. The amount of the flame retardant contained in the core layer (the weight of the flame retardant contained in the core layer per unit area) is preferably in the range of 1 to 100 g / m ² . By being in these ranges, the effect by the flame retardant mentioned above becomes still more remarkable.

  When the fibrous base material is impregnated with the slurry, it is impregnated and dried in the range of 500 to 1200% by the calculation method shown in equation 1. By being 1200% or less, the falling off of the slurry solid content from the prepreg is prevented, and the prepreg can be handled easily. By being 500% or more, delamination of the prepreg becomes difficult to occur.

  The pressure-sensitive adhesive layer is composed of a pressure-sensitive adhesive and a release paper, and as the pressure-sensitive adhesive, for example, an acrylic pressure-sensitive adhesive containing an acrylic polymer and a tackifier, and a solvent rubber-based pressure-sensitive adhesive containing styrene-butadiene It can be mentioned. Here, as a monomer which comprises the acrylic polymer of acrylic adhesive, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylic acid is mentioned, for example And (meth) acrylic acid alkyl esters such as butyl. Here, (meth) acrylic acid means methacrylic acid or acrylic acid. Moreover, as a tackifier, tackifiers, such as rosin type, a terpene type, a phenol type, a coumarone type, are mentioned. As a release paper, a known release paper coated with a silicone release agent is used. When the thickness of the pressure-sensitive adhesive is 50 to 180 μm, the adhesive strength is exhibited.

(Description of magnetic layer)
The magnetic layer according to the present invention contains strontium ferrite (a composite oxide of strontium and iron) as a main component, and, for example, chlorinated polyethylene is mixed as a binder component, and is sheet-shaped and then magnetized to be magnetized to be magnetized. It becomes a sheet. Ferrite has two types of particles, anisotropic and isotropic. The former is hexagonal plate-like, and is magnetized in one direction only, and the latter is close to spherical shape and is equally magnetized from any direction. Have. In the present invention, an anisotropic magnetic sheet or an isotropic magnetic sheet is used. The former generates a magnetic force only in one direction, and thus exerts a strong adsorptive power, and the latter generates the same magnetic force in all directions, so the adsorptive power becomes weak. The excellent anisotropy is clearer than the comparison between Example 1 and Example 3 and Example 2 and Example 4 even with the same thickness. The thickness of the magnetic sheet is preferably in the range of 0.32 to 3.08 mm. Within this range, the adsorption power is excellent and the weight is light and easy to handle.

For magnetization, one side of the sheet is alternately magnetized with N and S poles on one side of the sheet, and only one side of the sheet is adsorbed. The N pole and S on both sides of the sheet. The poles are alternately magnetized, and both sides can be adsorbed on both sides Multi-pole magnetized type, N pole on the entire surface of one side of the sheet and S pole on the entire surface of the opposite side, with magnetic force in the width direction There is a double-sided magnetism type that emits, and in the present invention, a single-sided multipolar magnetism type is preferably used.

  The decorative board having the magnetic layer of the present invention is formed by laminating the decorative layer, the mixed paper layer, and the glass fiber cloth base material prepreg as the core layer as needed, and heat is applied by a press such as a flat plate press or a continuous press. The pressure-sensitive adhesive layer is pressure-bonded and laminated on the outside of the core layer or the mixed paper layer after pressure-molding to obtain a decorative board, and the magnetic layer can be obtained by adhesion processing.

  From the bottom of the laminate structure of the decorative board layer, (B) mixed paper layer, (A) cosmetic layer, (B) mixed paper layer, (C) core layer, (A) cosmetic layer may be used, but By forming the laminated structure in order from the bottom into (C) core layer, (B) mixed paper layer, and (A) decorative layer, the formation of (C) core layer is less likely to appear on the surface of decorative plate, that is, excellent in smoothness. It has the advantage of In addition, the laminated structure of the decorative board layer is, in order from the bottom, (B) mixed paper layer, (C) core layer, (B) mixed paper layer, (A) decorative layer, so that the thickness becomes thicker. However, the handling property is improved and it becomes difficult to be damaged during handling.

The thickness of the decorative layer is preferably 0.43 to 0.69 mm. When it is in this range, the curl of the decorative board having the magnetic layer can be further suppressed. In particular, when the thickness of the decorative plate having the magnetic layer is in this range, the bending workability at normal temperature is also excellent.
Hereinafter, the present invention will be described in detail by way of examples and comparative examples.

(A) Cosmetic layer (melamine resin impregnated paper)
A resin paper containing melamine-formaldehyde resin as a main component is impregnated into a decorative paper printed with a wood grain pattern having a basis weight of 100 g / m ^{2 so} that the impregnation rate is 130% by the calculation method defined by Equation 1. It dried and manufactured the melamine resin impregnated paper.

(B) Mixed paper layer Magnesium silicate mixed paper of 180 g / m ² (trade name: GP-18, manufactured by Taigalex, 80% by weight of hydrous magnesium silicate (sepiolite), 10% by weight of pulp, 5% by weight of glass fiber, And 5% by weight of an organic binder), and the impregnation rate is 20 by the calculation method defined by the equation 1, guanidine phosphate (Apinone 307, manufactured by Sanwa Chemical Co., Ltd., total nitrogen content 31%) as a flame retardant % was impregnated so that the (per unit area 36 g / m ^2), dried to produce a guanidine phosphate impregnation mixed paper.

(C) Production of core layer glass fiber cloth base material prepreg (parts by weight are in terms of solid content)
As a binder, an acrylic resin emulsion (Product No. RAX-208, manufactured by Aika Kogyo Co., Ltd.) having a glass transition temperature (Tg) of 60 ° C. and an average particle diameter of 200 nm containing 2-ethylhexyl acrylate and methyl methacrylate as main monomers 32 Parts by weight,
As an endothermic metal hydroxide, 300 parts by weight of aluminum hydroxide having an average particle diameter of 8 μm,
As a silane coupling agent, 2.7 parts by weight of 3-glycidoxypropyltrimethoxysilane,
As a flame retardant, 29 parts by weight of guanidine phosphate (Apinon 303, manufactured by Sanwa Chemical Co., Ltd., total nitrogen content 39%) is compounded, water is added to obtain a slurry, and 40 g / g as a fibrous base material A glass fiber non-woven fabric of m ² was used to impregnate so as to have an impregnation ratio of 850% according to a calculation method defined by equation 1 and dried to manufacture a glass fiber cloth base prepreg.

From bottom to top, (C) one glass fiber cloth base material prepreg as core layer, (B) one guanidine phosphate impregnated mixed paper as mixed paper layer, (A) melamine resin impregnated cosmetic as decorative layer One sheet of paper was laminated, and hot pressed at a temperature of 132 ° C. and a pressure of 70 kgf / cm ² for 64 minutes with a flat plate press to obtain a decorative board with a thickness of 0.48 mm.

  A 50 μm-thick pressure-sensitive adhesive sheet (manufactured by Niei Kako Co., Ltd.) was prepared, in which an acrylic pressure-sensitive adhesive containing an acrylic resin as a main component was coated on silicone release paper. A pressure-sensitive adhesive sheet was attached to the core layer side (rear surface) of the decorative plate to obtain a decorative sheet.

Next, the release sheet on the back surface side of the decorative sheet is peeled off, and an anisotropic magnetic sheet having a thickness of 0.4 mm (made by Nichirei Magnet Co., having an adsorption force of 25 gf / cm ² or more and 2 mainly composed of strontium ferrite as a magnetic sheet) A decorative plate having a magnetic layer was obtained by performing adhesion processing on a single-sided multipole magnetized type having a magnetic flux density of 300 kPa or more and a magnetic flux density of 45 kPa or more.
In addition, an adsorption | suction force is a measured value by Yamato upper plate automatic balance spread type SD-800g, and a magnetic flux density is a measured value by KENETEC GAUSS METER TM701.

In Example 1, an anisotropic magnetic sheet having a thickness of 0.6 mm mainly composed of strontium ferrite as a magnetic sheet (manufactured by Nichirei Magnet Co., Ltd., adsorption force 40 gf / cm ² or more, 3.92 kPa or more, magnetic flux density 360 Gauss or more) The single-sided, multipolar magnetized type is adhesively processed to obtain a decorative board having a magnetic layer.

In Example 1, an isotropic magnetic sheet having a thickness of 0.4 mm mainly composed of strontium ferrite as a magnetic sheet (manufactured by Nichirei Magnet Co., Ltd., adsorption force 20 gf / cm ² or more, 1.96 kPa or more, magnetic flux density 250 Gauss or more) The single-sided, multipolar magnetized type is adhesively processed to obtain a decorative board having a magnetic layer.

In Example 1, an isotropic magnetic sheet having a thickness of 0.6 mm mainly composed of strontium ferrite as a magnetic sheet (manufactured by Nichirei Magnet Co., Ltd., adsorption force 30 gf / cm ² or more, 2.94 kPa or more, magnetic flux density 310 Gauss or more) The single-sided, multipolar magnetized type is adhesively processed to obtain a decorative board having a magnetic layer.

  The same procedure as in Example 1 was repeated except that a vinyl ester resin was used instead of guanidine phosphate.

Comparative Example 1
In Example 1, 110 g / m ² of aluminum hydroxide mixed paper (trade name: Sanwall, manufactured by Sansei Paper Co., Ltd., hydroxylated) as a fibrous base material of the mixed paper layer instead of 180 g / m ² of magnesium silicate mixed paper The same procedure as in Example 1 was repeated except that an aluminum mixing ratio of 69% by weight was used and a vinyl ester resin was used instead of guanidine phosphate.

Comparative example 2
The same procedure as in Example 1 was repeated except that the mixed paper layer was not impregnated with the flame retardant guanidine phosphate, but it was easily peeled off by hand after hot-press molding, and a decorative board was not obtained.

Comparative example 3
In Example 1, instead of 180 g / m ² of hydrous magnesium silicate mixed paper, 110 g / m ² of aluminum hydroxide mixed paper (trade name: Sanwall, manufactured by Sansei Paper Co., Ltd., aluminum hydroxide mixed ratio 69 wt%) It implemented similarly except having used.

Comparative example 4
(D) Production of glass cloth base material prepreg As a binder, a glass transition temperature (Tg) of 60 ° C. as a binder and a glass transition temperature (Tg) of 115 g / m ² of glass cloth (made by Kurashiki Spinning Co., Ltd.) The acrylic resin emulsion (product number RAX-208, manufactured by Aika Kogyo Co., Ltd.) having an average particle diameter of 200 nm is impregnated so as to have an impregnation ratio of 30% according to the calculation method defined by Equation 1 and dried to obtain a glass cloth substrate A prepreg was manufactured.
It implemented similarly, except having laminated | stacked one sheet of (D) glass cloth base material prepreg from the bottom, and one sheet of melamine resin impregnated decorative paper as a (A) decorative layer used in Example 1

The contents of the mixed paper layer are shown in Table 1.

The slurry composition of the core layer is shown in Table 2.

The content [g / m ² ] of each component in the core layer is shown in Table 3.

The contents of the pressure-sensitive adhesive layer and the magnetic layer are shown in Table 4.

The layer configuration of the decorative board is shown in Table 5. In addition, the water balance paper in Table 5 means aluminum hydroxide mixed paper.

Table 6 shows the evaluation results of the decorative sheet and the decorative sheet with an adhesive.

Table 7 shows the evaluation results of the evaluation of the decorative plate having the magnetic layer.

The evaluation results of the decorative boards of Examples 4 and 5 and Comparative Example 4 are shown in Table 8.

The evaluation method was as follows.
(1) Interlayer Strength of Decorative Plate The presence or absence of delamination of the decorative plate after hot-pressing was confirmed, and no delamination after hot-pressing was evaluated as ○. Boiling resistance test (JIS K 6902: 2007 “Thermosetting resin high-pressure decorative board test method”) was conducted. In the boiling resistance test, no abnormality was rated as ○.

(2) Thickness The thickness of the decorative plate was measured by a micrometer.

Non-combustibility (3) Total calorific value The decorative plate and the decorative sheet with adhesive were subjected to a heat generation test of a 20-minute test with a corn calorimeter according to ISO 5660.
(4) Shape retention The total calorific value is 8 MJ / m ² or less, and the maximum heating rate is 200 kW / m ² continuously for 10 seconds or more in the heat generation test / evaluation method of the 20 minutes test with a corn calorie meter based on ISO5660. The case where there is no crack, crack, etc. which penetrates to the back surface in the test body after the test is not exceeded (○ does not exceed the shape) is regarded as × when there is a crack or crack (the shape is not maintained) .

(5) Adhesive force of decorative sheet with adhesive A fragment of 300 mm × 150 mm in size was cut out from the decorative sheet with adhesive. The silicone release paper was peeled off from the fragments, and the pressure-sensitive adhesive layer and an aluminum plate with a thickness of 2 mm were pasted together. Furthermore, on them, a hand roller weighing 2 kg was reciprocated twice. The product produced by the above steps is used as a test sample. Among the test bodies, the surface on the cosmetic layer side was bonded to a jig of 40 mm × 40 mm using an adhesive (cyanoacrylate).

  After curing for 1 day at a temperature of 23 ° C and a relative humidity of 50%, the force in the direction in which the aluminum plate and the adhesive layer separate from the test body is measured using a bond strength tester (manufactured by Oxjack Co., Ltd.). In addition, the tensile strength was measured. The value of tensile strength was taken as the measurement value of adhesive strength.

(6) Flame resistance test (front and back)
In the test method by the 45 ° Meckel burner method in accordance with Article 4 paragraphs 3 to 7 of the Fire Service Act enforcement regulations, the process from removing the burner after firing to raising the flame and stopping the burning state The time (afterflame time) was measured. The elapsed time (remaining time) until burning ceased without raising the flame after removing the burner after the flame was measured. The area to be carbonized (carbonized area) was measured within the time until the burning state ceases after the flame is applied.

(7) Adhesive strength plate A decorative plate having a magnetic layer of 40 mm square was attached to the base of the steel plate, and the number of sheets capable of holding A4 size plain paper was counted.
In Comparative Example 4, the curl of the decorative plate itself was strong, and the magnet was pulled to the side of the decorative layer, so the adsorptive power to hold the plain paper with the magnet was reduced.

(8) Appearance (Smoothness and Translucency)
The decorative board was observed visually. If there were no cracks or wrinkles in the cosmetic layer, or irregularities in the base, the smoothness was regarded as "o", and if there were slight irregularities, the smoothness was regarded as "Δ".
Further, a metal straight was attached to the back of the decorative plate of Example 4 and Comparative Example 4, and light of a fluorescent lamp was irradiated from the back, and the decorative plate was photographed in that state. The photograph of the decorative board of Example 4 is shown in FIG. 4, and the photograph of the decorative board of Comparative Example 4 is shown in FIG. In FIG. 5, the metal straight was seen through but in FIG. 4 it was not seen. That is, since the surface of the decorative plate of Example 4 had high concealability, it did not pick up the color of the base. On the other hand, since the decorative board of Comparative Example 4 has low concealability, the unevenness of the glass cloth and the color of the base were picked up.

(9) Evaluation of Warpage of Decorative Plate A 50 mm × 300 mm sample was cut out from the decorative plate. The fiber direction of the decorative board is parallel to the short direction of this sample. The sample was aged for 24 hours in a room temperature of 40 ° C. and a humidity of 30%. Thereafter, the sample was placed on a horizontal plane, and one end in the longitudinal direction of the sample was pressed against the horizontal plane. Then, the distance between the opposite end in the longitudinal direction of the sample and the horizontal plane was measured. This distance is taken as the warp height. The warpage height reflects the size of the sample curl.

(10) Dimension change rate It measured based on the dimensional stability test of JIS K 6902: 2007 "thermosetting resin high-pressure decorative board test method".

DESCRIPTION OF SYMBOLS 1 cosmetic layer 2 mixed paper layer 3 core layer 5 adhesive layer 6 decorative board layer 7 adhesive sheet decorative sheet 8 anisotropic magnetic layer 9 isotropic magnetic layer 21 decorative plate having a magnetic layer 22 decorative plate having a magnetic layer

Claims (14)

A decorative sheet with an adhesive comprising a decorative layer and an adhesive layer, and a magnetic layer,
The decorative board layer includes a decorative layer and a mixed paper layer, the decorative layer is made of a thermosetting resin-impregnated decorative paper containing a thermosetting resin in the decorative paper, and the mixed paper layer is a silica gel having bonding water. It consists of a thermosetting resin or nitrogen-based flame retardant or a flame retardant-impregnated mixed paper containing a phosphorus / nitrogen-based flame retardant using magnesium mixed paper as a base material, and a magnetic layer is included on the back side of the pressure-sensitive adhesive layer. Decorative plate having a magnetic layer to be   The decorative board having a magnetic layer according to claim 1, wherein the decorative board layer further includes a core layer made of a prepreg including a fibrous base material.   The decorative board having a magnetic layer according to claim 2, wherein the laminated structure of the decorative board layer is the core layer, the mixed paper layer, and the decorative layer in order from the back surface side. The decorative board according to claim 1, wherein the content of the nitrogen-based flame retardant or the phosphorus / nitrogen-based flame retardant in the mixed paper layer is 9 to 90 g / m ² .   5. The decorative board having a magnetic layer according to claim 4, wherein the phosphorus-nitrogen based flame retardant in the mixed paper is made of one or more selected from the group consisting of guanidine phosphate and guanyl urea phosphate.   The decorative plate having a magnetic layer according to claim 1, wherein the thermosetting resin is an amino-formaldehyde resin.   The decorative board having a magnetic layer according to claim 2, wherein the prepreg of the core layer contains an endothermic metal hydroxide and a binder component in the fibrous base material.   The decorative board having a magnetic layer according to claim 7, wherein the binder component comprises an acrylic resin emulsion.   The decorative board having a magnetic layer according to any one of claims 2, 3 or 7, wherein the core layer contains a flame retardant. Content of the said flame retardant is 1-100 g / m < ² >, The decorative board which has a magnetic layer of Claim 9 characterized by the above-mentioned.   The decorative plate having a magnetic layer according to claim 9 or 10, wherein the flame retardant is a nitrogen-based flame retardant or a phosphorus / nitrogen-based flame retardant.   The decorative board having a magnetic layer with a pressure-sensitive adhesive according to claim 11, wherein the nitrogen content in the phosphorus-nitrogen based flame retardant is 1 to 50% by mass.   The thickness of the said decorative board layer is 0.43-0.69 mm, The decorative board which has a magnetic layer with an adhesive in any one of the Claims 1-3 characterized by the above-mentioned.   The thickness of the said magnetic layer is 0.32 mm-3.08 mm, The decorative board which has a magnetic layer of Claim 1 characterized by the above-mentioned.