JPS62152733A - Manufacture of panel - Google Patents

Abstract

PURPOSE:To reduce the number of steps in process and at the same time obtain a patterned panel with high decorativeness in design by a method wherein an impregnable sheet, onto which predetermined pattern is applied and which is treated with thermosetting resin, is put onto the surface of a molding compound so as to be formed by hot-pressing. CONSTITUTION:First, abstract pattern layers 2 are printed with cellulose acetate- based gravure printing ink on a titanous paper. Secondly, the resultant printed paper is immersed in melamine resin solution 1 and dried so as to prepare an impregnated sheet 3. On the other hand, a sheet molding compound (SMC) 4 containing 35% of glass is prepared. SMC 4 and the impregnated sheet 3 are piled up in the order named on a plywood 5 so as to seat them in a flat sheet press in order to press them at 150 deg.C under a pressure of 15kg/cm<2> for 20min and cooled down as the pressure is held. As a result, a FRP decorative panel with pattern layers with high decorativeness in design on its surface is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing panels, and more specifically, a method for manufacturing panels that can be used for furniture, architectural interior materials, surface materials for structures, etc. Regarding.

[Prior art and its problems]

Flat or curved plate-like structures, ie, panels used as building materials, are made of, for example, thermoplastic resin.

Thermosetting resin or fiber reinforced plastic (FRP)
It is a sheet of composite plastic such as, or a combination of this sheet and a supporting material, and the surface thereof is particularly designed with colors, patterns, shapes, etc.

The manufacturing method of the panel includes molding compounds (hereinafter referred to as MC) such as sheet molding compounds (SMC) and bulk molding compounds (BMC) made by thickening and bonding thermosetting unsaturated polyester resin compounds. There is a method in which reinforcing fibers are viscous, molded under heat and pressure in a mold and cured, and the resulting FRP panel is decorated with surface painting or plating. However, the decoration of this FRP panel requires a lot of effort and can only be applied in a single color without any pattern. There is also a method of manufacturing panels by mixing pigments into SMC and subjecting it to hot pressure molding. Panels with color and flow patterns can be produced by this method. However, the types of patterns are limited, and the patterns are not reproducible. Furthermore, a method has been proposed in which a panel is manufactured by stacking printed paper with a desired pattern on the surface of an SMC and molding it under heat and pressure. By this method, panels with various reproducible designs can be manufactured. However, the printing paper is not sufficiently impregnated with the resin in the SMC, the panel surface has poor abrasion resistance, and the printed pattern may easily disappear.

This invention was made in order to solve the problems of the conventional method described above, and its purpose is to reduce the labor involved in the manufacturing process and to produce panels with high design and reproducible patterns. The goal is to provide a method to do so.

[Means for solving problems]

The present inventors made printing paper impregnated with thermosetting resin into MC.
The present invention was completed based on the discovery that hot-press molding is effective in achieving the object of the present invention. That is, the method for manufacturing a panel of the present invention includes treating an impregnated sheet with a predetermined pattern with a thermosetting resin, and then hot-pressing it onto a molding compound (MC) surface. It's a method.

In the method of this invention, a desired pattern is applied to an impregnated sheet using a conventional ink composition.

The ink composition used in this invention includes a vehicle, a pigment or dye colorant, a plasticizer, a stabilizer,
A product obtained by kneading other additives, a solvent, or a diluent is used, and a slow-drying vehicle with a relatively low degree of polymerization is used as the vehicle. As the vehicle for this ink, thermosetting resins such as low polymerization degree melamine resins and alkyd resins are preferred, but drying oils,
Plasticizers, mineral oils, synthetic resins other than those mentioned above, cellulose and rubber derivative waxes can also be used.

Preferred solvents that can be used in this ink include cellosolve, glycol-ether, and water, but hydrocarbons, halogenated hydrocarbons, esters, nitrogen-containing compounds, sulfur compounds, etc. can also be used. . As the pigment used in this ink, for example, disazo-based, polyazo-based, quinacridone-based, and threne-based pigments are preferred, and organic and inorganic pigments such as phthalocyanine-based, batt-based, triphenylmethane-based, and metal complex salt-based pigments may also be used. can. The component composition of this ink varies depending on the types of components, but can be within the following range of amounts, for example.

In addition, hereinafter, "parts" indicating a ratio shall mean parts by weight.

Pigment: 1 to 5 parts Vehicle: 5 to 10 parts Solvent: 100 parts The impregnated sheet used in this invention includes paper made from wood bulb, straw bulb, linter pulp, etc., mixed paper, and nonwoven fabric. A preferred sheet is link paper with high α-cellulose purity from the viewpoint of ink permeability.

In addition, even if a coloring agent such as titanium oxide is added as necessary to impart concealing properties to this sheet, it is also possible to apply a highly pure α-cellulose bulb on top of ordinary decorative paper containing titanium oxide. A double-layered paper may be used, or a laminate of a paper made from a valve with a high α-cellulose purity and a paper imparted with concealment properties may be used.

The α-cellulose purity of the valve used for the seat is as follows:
95% or more is preferable, and the tsubom of the base material is 50 to 50%.
150g/cd is appropriate.

In this invention, the method of applying a desired pattern to the impregnated sheet with ink, that is, the printing method, is a conventional method such as gravure printing, letterpress printing, offset printing, silk screen printing, offset gravure printing, electrostatic printing, and jet printing. Any method is fine.

In the method of the invention, an impregnated sheet is treated with a thermosetting resin to impregnate the sheet with the thermosetting resin. This treatment of the thermosetting resin is carried out after the printing process of the impregnated sheet, but it may be carried out before or simultaneously with the printing process as long as it does not contradict the purpose of the present invention. The thermosetting resin used in this process is a low molecular weight intermediate or a low degree of polymerization, and is a liquid at room temperature or a solid that becomes fluid when heated, and is molded and hardened when heated further. .

The types include melamine resins, unsaturated polyester resins, diallyl phthalate resins, phenol resins, urea resins, benzoguanamine resins, acetoguanamine resins, and epoxy resins, and those that become transparent after heat curing are desirable.

In the method of this invention, a sheet treated with a thermosetting resin is superimposed on the MC surface and hot-pressed.

This MC is an unsaturated polyester resin containing colorants, fillers, thickeners, curing agents (catalysts), lubricants, reinforcing materials and other additives as necessary, and is itself used as a molding material. be.

Here, the term "unsaturated polyester resin" refers to unsaturated alkyd resins, i.e., unsaturated dibasic acids or their anhydrides alone or products obtained by adding saturated dibasic acids and esterifying them with glycol, diallyl phthalate, etc. A substantially uncrosslinked prepolymer (so-called β-polymer) of a saturated or unsaturated dibasic acid and an unsaturated alcohol, or a polyester selected from a mixture thereof, is converted into a reactive monomer having an ethylenically unsaturated bond. This includes those dissolved and, if necessary, a polymerization inhibitor added.

In the above, as the unsaturated dibasic acid or its anhydride, maleic acid or its anhydride having an ethylenic double bond, fumaric acid, mesaconic acid, itaconic acid or its anhydride, etc. are used.

Examples of saturated dibasic acids include phthalic acid, substituted phthalic acids, anhydrides thereof, adipic acid, and the like. Further, as glycols that react with these dibasic acids to form esters, ethylene glycol, diethylene glycol, 1-lyethylene glycol, propylene glycol, dipropylene glycol, butanediol, and the like are used. Moreover, allyl alcohol and the like are used as the unsaturated alcohol. The reaction conditions for obtaining the above-mentioned polyester from these acids and alcohols may be different, but in any case, the polyester can be prepared by a known method. In addition, the reactive seven polymers having ethylenically unsaturated bonds that dissolve these unsaturated polyesters include styrene, divinylbenzene, vinyltoluene,
Vinyl acetate, methyl methacrylate, α-methylstyrene, diacrylphthalate, etc. are used.

Unsaturated polyester is produced by mixing fillers, thickeners, curing agents, low shrinkage additives, colorants, and other additives with consideration to pot life into the resulting unsaturated polyester resin. A resin compound is obtained.

This filler consists of aluminum hydroxide, magnesium carbonate,
The material is selected from among barium sulfate, calcium sulfate, calcium carbonate, alumina, stone powder, FRP waste, silica sand, glass fiber, clay, kaolin, talc, etc., taking into consideration aesthetic appearance and strength. Various thermoplastic polymers such as polystyrene and polymethyl methacrylate are used as low shrinkage additives. Preferably, it is dispersible or soluble in the above-mentioned reactive monomer. As the thickener, oxides and hydroxides of metals, preferably alkaline earth metals, such as magnesium oxide, magnesium hydroxide, calcium oxide, and lithium oxide, can be used. The curing agent (catalyst) includes t-butyl perbenzoate, cumene hydroperoxide, etc. for high temperature molding (120°C or higher) so that an appropriate curing effect can be obtained at the molding temperature of MC.
(70℃ or higher), lauroyl peroxide, methyl isobutyl ketone peroxide, etc.
℃ or above), bis-(4-t-butylcyclohexyl)
Peroxycarbonate, t-butyl peroctoate + CO or Ca accelerator, etc. are used, and for room temperature curing, a combination of methyl ethyl ketone peroxide and an organometallic compound accelerator is used. The above-mentioned temperature ranges indicate general guidelines for use, and each curing agent may not be used at temperatures slightly outside the above-mentioned temperature ranges.

As the coloring agent, known dyes or pigments are used in types and amounts depending on the desired color tone. Acidic to neutral (oil-soluble, dispersible) dyes and pigments are preferred. If necessary, an internal mold release agent such as zinc stearate, a surface improving agent such as finely powdered polyethylene, etc. may be added to the above compound.

An unsaturated polyester resin compound can be obtained by mixing the above components using a conventional stirring tank mixer, kneader, or the like. Although the order of addition of each component is arbitrary, it is preferable to add the thickener last. It is preferable to carry out vacuum defoaming during mixing because a bubble-free compound can be easily obtained.

Preferred embodiments of S that can be used in this invention
As MC, there is SMC which is made as follows.

A resin powder is coated on one side of the first separator film and the second separator film in a desired layer thickness, and the glass is cut! A fiber-reinforced sheet (glass chopped stone land mat) in which He1l strands are bonded in a mat-like manner is prepared, and then the fiber sheet is sandwiched between each resin powder layer and pressurized from the outside, resulting in defoaming and compounding. After impregnating the fiber reinforced sheet, the compound is heated and aged to obtain the desired SM.
C can be obtained. Glass chopped strand mats that can be used here include 200~1,
000 g/l, preferably 450 to 900 g/l.

In the method of this invention, a MC and thermosetting resin impregnated sheet is hot pressed. Typically, thermoforming is carried out in an open plate press or in a mold;
This is for normal plastic thermopressing molding, taking into consideration the uniformity of temperature distribution, the method of cutting, demolding, desired surface condition, etc. This hot-press molding (compression molding) can be carried out in accordance with a normal plastic compression molding method, taking into consideration the curing conditions of the thermosetting resin absorbed into the MC and the sheet.

The conditions for hot press molding vary depending on the type of molding material, but
For example, the temperature is 100 to 150°C (preferably 1
20-130℃), pressure 20-300Kg/cd
(preferably 80-120Kg/d) 20 hours
~100 seconds/3m++.

When using an open plate press, molding can be carried out under the same conditions as those for molding ordinary thermosetting resin plates such as diacrylphthalate, melamine, and benzoguanamine.

In addition, it can be molded in an overlapping manner with a supporting material if necessary. Supporting materials that can be used in this invention include wood, plywood, wood grains such as verticle board, gypsum-based materials such as gypsum board and gypsum slag board, pulp cement board, asbestos cement, wood chip cement board, etc.
Iffl cement board, GRC and concrete, iron,
A metal plate such as aluminum or copper can be used.

Furthermore, an embossing plate can also be used to provide an uneven pattern on the surface.

Next, an example of a panel according to the present invention will be described with reference to the accompanying drawings.

The drawing is a schematic cross-sectional view showing an example of a panel according to the invention. This panel example consists of a sheet 3 on which a pattern layer 2 is printed and an SMG molded product 4 provided on a support material 5. The sheet 3 is impregnated with a thermosetting resin, and the sheet surface is coated with the resin layer 1. covered with. The SMG molding 4 is provided on a support material 5 (for example a board, metal plate, etc.), and the sheet 3 is provided on the SMC molding 4. This sheet 3 is obtained by hot-pressing a sheet impregnated with a thermosetting resin.

Hot-press molded products are used for various purposes after normal treatment and processing.

〔Effect of the invention〕

In this invention, since a printing sheet impregnated with a thermosetting resin is layered with MC and hot-press molded, unique effects not seen in the past can be obtained. In other words, since panel painting can be done at the same time as MC press molding,
The number of processes can be reduced compared to conventional manufacturing methods. Since a printed sheet is used, patterns with high design quality can be repeatedly produced, and deep drawing embossing can be easily performed. Since it is impregnated with a thermosetting resin in advance, the abrasion resistance and water resistance of the surface can be improved. Therefore, applications that take advantage of water resistance and abrasion resistance, such as pool aquarium walls, bathroom walls, etc.
It can be used on the surface of shipping containers, etc.

〔Example〕

The method for manufacturing the panel of the present invention will be explained using the following specific examples.

Example 1 An abstract pattern layer was printed on 80 g/Td titanium paper using cellulose acetate-based gravure ink, and a melamine resin liquid (composition: American Cyanamid Co., Ltd. Cymel 4) was printed on the printed paper.
12, 45 parts of water, and 5 parts of isopropanol) and dried to prepare an impregnated sheet.

Separately, SMC with a glass content of 35% was prepared as follows. 50μ thick polypropylene first and second
A resin compound having the composition shown below was coated on one side of each separator film in a predetermined layer thickness.

Polyester resin 100 parts Barium sulfate 60 parts t-butyl perbenzoate 1 part Zinc stearate 1
Part pigment
2 parts Mg0 2 parts Next, a fiber-reinforced sheet (Glass Chopped Strand Mat; manufactured by Unitika U-M Glass Co., Ltd., Chopped Strand Mat EM-300) in which cut glass LLN strands were adhered in a mat shape was prepared. A glass sheet prepared with each coated resin compound layer was sandwiched and pressurized from the outside to defoam and impregnate the compound into the glass sheet. Thereafter, the compound was heated and aged to obtain the desired SMC.

5.511II11 thick plywood, the above SMC, and the above impregnated sheet were stacked one on top of the other and placed in a flat plate press. 150℃, 15 parts g/ca! , and was pressed for 20 minutes, and cooled while the pressure was applied.

As a result, an FRP decorative panel having a highly designed pattern layer on the surface was obtained.

The panels obtained in Example 1 and panels prepared similarly to Example 1 except that they were not treated with a thermosetting resin were tested for the physical properties shown in the table below.

The results are shown in the table below.

[Brief explanation of drawings]

The accompanying drawing is a schematic cross-section showing an example of a panel according to the method of the invention. DESCRIPTION OF SYMBOLS 1... Resin layer, 2... Pattern layer, 3... Thermosetting resin impregnated sheet, 4... SMG molded product, 5... Supporting material.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a panel, which includes treating an impregnated sheet with a desired pattern with a thermosetting resin, and then overlaying the sheet on a molding compound surface and hot-pressing the sheet. 2. The manufacturing method according to claim 1, wherein the molding compound is reinforced with glass fiber strands. 3. The manufacturing method according to claim 2, wherein the reinforcing glass fiber is a glass chopped strand mat.