JP2007245548A - Decorative sheet made of thermosetting resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thick decorative sheet made of a thermosetting resin having low dimensional shrinkage. <P>SOLUTION: A prepreg as a core layer 2, which is obtained by impregnating a woven or non-woven fabric of an inorganic fiber with a slurry containing an organic resin component, calcium carbonate and a silane coupling agent and by drying, is subjected to heat press molding together with a dried, resin-impregnated decorative paper 1, which is obtained by impregnating a decorative paper with a resin liquid consisting mainly of a thermosetting resin and by drying. The combination ratio of the organic resin component and the calcium carbonate is 1:3-20 based on a weight ratio of the solids, and as the calcium carbonate there are used a plurality of kinds having an average particle size in the range of 1-5 μm. The combination ratio of the organic resin component and the silane coupling agent is 1:0.01-0.5 based on a weight ratio of the solids. The content of the slurry in the prepreg is set to 500-2,000%. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermosetting resin decorative board.

Conventionally, a melamine resin decorative board that is integrated with heat and pressure using a melamine resin impregnated paper as a decorative layer and a phenol resin impregnated paper in which a kraft paper is impregnated with a phenol resin is known as a core layer. This melamine resin decorative plate has a main thickness of 0.8 to 1.4 mm, and is used for vertical surfaces such as a horizontal surface, a wall surface, a pillar and the like such as a wash counter, a desk and a table because of its excellent physical properties. In recent years, a thick decorative board having a thickness of 3 to 10 mm is also known for the purpose of improving impact resistance. Usually, 15 to 50 phenol resin-impregnated papers are laminated with melamine resin-impregnated papers, It is pressure formed.
JP-A-5-318640 JP-A-9-164645 JP-A-9-254331

  However, since the core layer is thick, the balance with the decorative layer cannot be achieved, and there is a drawback that dimensional shrinkage due to the influence of temperature and humidity is large. Further, when an inorganic filler having poor reactivity is used for the core layer, there is a drawback that the adhesiveness to the decorative layer and the strength of the decorative plate are weak.

  The present invention has been studied to solve the above-described problems, and a woven or non-woven fabric of inorganic fibers is impregnated with a slurry containing an organic resin component and a non-hydrated inorganic substance such as calcium carbonate and a silane coupling agent, and dried. It is a thermosetting resin decorative board having a prepreg as a core layer.

  In the present invention, a woven fabric or a non-woven fabric of inorganic fibers is used as the base material of the core layer instead of the conventional kraft paper, so that the dimensional shrinkage caused by the base material can be suppressed, and the conventional heat is used as the resin impregnating the base material. In addition to organic resin and calcium carbonate from curable resin alone, slurry containing silane coupling agent is used, so dimensional shrinkage due to the effect of resin can be suppressed, and thermosetting resin decorative board integrated with decorative layer is also dimensioned Shrinkage is extremely small. In addition, the adhesion between the decorative layer and the core layer becomes strong. Hereinafter, the present invention will be described in detail.

The base material for the core layer used in the present invention is a woven or non-woven fabric of inorganic fibers. Examples of the inorganic fibers include glass fibers, rock wool, carbon fibers, and the basis weight of the base material is 10 to 200 g. The range of / m ² is preferable, and it is particularly preferable to use glass fibers that are excellent in the impregnation property of the slurry.

  The slurry impregnated in the base material is a slurry containing only an organic resin component and calcium carbonate which is a non-water-containing inorganic substance as a filler. A phenol-formaldehyde resin that can be suitably used because it is excellent in various physical properties such as heat resistance and dimensional change of the finished product, and particularly excellent in impact resistance is preferable.

  The amino-formaldehyde resin is obtained by reacting an amino compound such as melamine, urea, benzoguanamine, acetoguanamine and formaldehyde.

  Phenol-formaldehyde resin is composed of 1 to 3 moles of formaldehyde with respect to 1 mole of phenolic hydroxyl groups of phenols such as phenol, cresol, xylenol, octylphenol, phenylphenol, bisphenol A, bisphenol S, and bisphenol F. It can be obtained by reacting under a basic catalyst such as sodium oxide or triethylamine.

  There is no restriction | limiting in particular as calcium carbonate, Heavy calcium carbonate, light calcium carbonate (precipitation calcium carbonate), etc. can be used. Heavy calcium carbonate having an average particle size of 0.05 to 10 μm, more preferably 1 to 5 μm is preferable. If the lower limit is not reached, secondary aggregation tends to occur and agglomeration tends to occur, and impregnation suitability tends to deteriorate. The surface of the decorative resin decorative board is not smooth, resulting in poor appearance. Light calcium carbonate refers to calcium carbonate that is chemically produced by firing limestone, and heavy calcium carbonate refers to finely powdered calcium carbonate prepared by dry or wet pulverization of white crystalline limestone.

  The blending ratio of the organic resin and calcium carbonate is preferably 1: 3 to 20 in terms of the solid content ratio. If the calcium carbonate is less than the lower limit, the warp of the decorative board is large, and if the upper limit is exceeded, the water resistance of the decorative board is increased. Strength will fall. More preferably, a plurality of types having different average particle diameters are used for closest packing, for example, those having an average particle diameter of 1-2 μm and those having an average particle diameter of 4-5 μm are 80-50: 50- When used at a ratio of 20, the filling rate is improved, the core layer becomes strong, and the moisture-proof performance is improved. Except for this blending ratio, aggregation occurs between the calcium carbonate particles, and the impregnation property with respect to the inorganic fiber base material tends to decrease.

  The impregnation rate of the slurry to the base material is preferably 500 to 2000% by the calculation method represented by Equation 1, and if the impregnation rate exceeds the upper limit, the solid content is dropped off and is difficult to handle, and if the lower limit is not reached Delamination easily occurs.

  The content of the organic resin component in the prepreg is desirably 4 to 30% by the calculation method represented by Formula 2, and if the lower limit is not reached, the heat resistance deteriorates, and if the upper limit is exceeded, the strength and adhesion are poor. It becomes easy.

  In addition, a silane coupling agent is blended in the slurry to improve adhesion to the resin-impregnated decorative paper described below, and reacts with the methylol group of the amino-formaldehyde resin, the hydroxyl group of the phenol-formaldehyde resin, and the glass fiber. It is firmly bonded in three dimensions. The blend ratio of the organic resin component and the silane coupling agent is preferably 1: 0.01 to 0.5 in terms of solid content, and if the silane coupling agent is less than the lower limit, sufficient adhesion to the surface design layer is achieved. Cannot be obtained, and if it exceeds the upper limit, the viscosity is remarkably increased and impregnation becomes difficult.

  Among the silane coupling agents, epoxy silane coupling agents are particularly preferable from the viewpoint of adhesion. For example, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ- Examples thereof include glycidyloxypropylmethyldiethoxysilane and glycidoxypropyltrimethoxysilane.

The thermosetting resin decorative board of the present invention is formed by laminating a plurality of prepregs obtained by impregnating a slurry into a substrate and drying, a resin-impregnated decorative paper as a decorative layer, and a resin-impregnated surface paper as necessary In addition, it is obtained by hot pressing with a flat plate press, a continuous press or the like, and the warpage is greatly reduced. The hot pressure conditions may be a temperature of 120 to 140 ° C. and a pressure of 40 to 70 kgf / cm ² .

The resin-impregnated decorative paper is obtained by impregnating a decorative liquid for decorative board of 80 to 160 g / m ^{2 with} a resin liquid made of a thermosetting resin and drying it. As the thermosetting resin, the amino-formaldehyde described above is used. Resins are preferably used because of their excellent heat resistance and wear resistance.

The resin-impregnated surface paper is used for the purpose of improving the abrasion resistance when printing paper is used as decorative paper, and is made of a thermosetting resin on the surface paper that becomes transparent after impregnation of 20 to 40 g / m ^2. As the thermosetting resin, an amino-formaldehyde resin is preferably used as in the case of decorative paper.

  EXAMPLES Hereinafter, although an Example is given and demonstrated in detail, this invention is shown more concretely and is not specifically limited. In addition, the part in an Example and a comparative example shows solid content weight.

^On a glass fiber nonwoven fabric with a core layer of 100 g / m ² , 60 parts of calcium carbonate with an average particle diameter of 2 μm, 27.5 parts of calcium carbonate with an average particle diameter of 5 μm, and glycidoxypropyltrimethoxy with respect to 12 parts of phenol-formaldehyde resin A slurry containing 0.5 part of silane (SH-6040: manufactured by Toray Dow Corning Co., Ltd.) was impregnated so that the impregnation ratio shown in Formula 1 was 1000% to obtain a prepreg.

In this case, the weight of the solid content after slurry impregnation is 1100 g / m ² from Equation ¹ , and the slurry content is 1000 g / m ² by subtracting the weight of the glass fiber nonwoven fabric from 1100 g / m ² .

Furthermore, 1000 g / m ² contains 12 parts of phenol resin, 87.5 parts of calcium carbonate, and 0.5 parts of silane coupling agent, so that the organic resin component is 120 g / m ² and calcium carbonate is 875 g / m ^2. It is.

  Therefore, the content (%) of the organic resin component in the prepreg calculated from Equation 2 is 11.0% by 120 / (100 + 120 + 875) × 100.

A plain pattern decorative paper having a decorative layer basis weight of 120 g / m ² was impregnated with a melamine-formaldehyde resin so that the impregnation ratio represented by Equation 1 was 100% to obtain a melamine resin-impregnated decorative paper.

Laminate one sheet of melamine resin impregnated decorative paper, four sheets of prepreg, and one sheet of melamine resin impregnated decorative paper in order from the bottom of the thermosetting resin decorative board, and use a flat finish plate at 140 ° C., 100 kg / cm ² , The thermosetting resin decorative board of Example 1 was obtained by hot pressing under the condition of 90 minutes.

Comparative Example 1 (when the proportion of calcium carbonate is less than the lower limit)
In Example 1, it carried out similarly except having set it as 20 parts of calcium carbonate with an average particle diameter of 2 micrometers, and 8 parts of calcium carbonate with an average particle diameter of 5 micrometers.

Comparative Example 2 (when the proportion of calcium carbonate exceeds the upper limit)
In Example 1, it carried out similarly except having used 190 parts of calcium carbonate with an average particle diameter of 2 micrometers and 80 parts of calcium carbonate with an average particle diameter of 5 micrometers.

Comparative Example 3 (when the blending ratio of the silane coupling agent is less than the lower limit)
In Example 1, it implemented similarly except having mix | blended 0.05 part of silane coupling agents.

Comparative example 4 (when the blending ratio of the silane coupling agent exceeds the upper limit)
In Example 1, it implemented similarly except having mix | blended 7 parts of silane coupling agents.

1 sheet of melamine resin-impregnated decorative paper, 4 sheets of phenol resin-impregnated paper, 1 sheet of melamine resin-impregnated decorative paper are laminated and heat-pressed using a flat finish plate at 140 ° C, 100 kg / cm ² for 90 minutes. The molded product was used as a decorative board of Comparative Example 5.

  The evaluation results are shown in Table 1.

The evaluation method was as follows.
Boiling resistance test: Measured based on JIS K 6902. Abnormality was marked with ◯ and swelling was marked with x.
Dimensional change rate: Measured based on JIS K 6902.
Impact resistance: Measured based on JIS K 6902, with cracks marked with x, without cracks marked with ◯.
Appropriate impregnation: A glass fiber base material that was impregnated with the slurry for a desired resin ratio was marked with “◯”, and a glass fiber base material that was agglomerated and the impregnation amount could not be controlled was marked with “x”.

The structure sectional view of the thermosetting resin decorative board of the present invention.

Explanation of symbols

1 resin impregnated decorative paper layer 2 core layer 3 thermosetting resin decorative board

Claims (3)

A thermosetting resin decorative board comprising a core layer made of a prepreg obtained by impregnating a woven fabric or nonwoven fabric of an inorganic fiber with a slurry using an organic resin component and calcium carbonate as an inorganic filler and drying the slurry. The thermosetting resin decorative board according to claim 1, wherein a blending ratio of the organic resin component and the calcium carbonate is 1: 3 to 20 in terms of a solid content weight ratio. The thermosetting resin makeup according to claim 1, wherein the slurry contains a silane coupling agent and has a weight ratio of 0.01 to 0.5 with respect to the solid content 1 of the organic tree component. Board.

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