JP2000108149A - Manufacture of heat-curable resin molded product with surface pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a heat-curable resin molded product with a surface pattern which can visualize a pattern giving a feel of depth and transparency and is less costly for manufacture. SOLUTION: This method for manufacturing a heat-curable resin molded product is to load a molding material for a first surface layer material imparting a pattern to the surface of a molded product and a molding material for a second surface layer material composed mainly of a heat-curable resin, lapped over each other in a molding tool, and thermally compression-mold these lapped molding materials for the first surface layer material and molding material for the second surface layer material to obtain the molded product with a surface pattern. In this case, the molding material for the first surface layer material contains 3-30 pts.wt. pattern material, 1-15 pts.wt. polyfunctional isocyanate and 1-15 pts.wt. polyol for 100 pts.wt. heat-curable resin component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a thermosetting resin molded article having a pattern on a surface used for a house interior material, a house exterior material, a bathroom substrate, a washbasin substrate and the like.

[0002]

2. Description of the Related Art Interior and exterior materials for houses, base materials for bathrooms,
Alternatively, the appearance of a thermosetting resin molded product used for a wash basin base or the like is improved by patterning the surface with coloring or the like.

In the hand lay-up method of FRP, a transparent resin is first applied to the surface of a molding die and gelled, and then a crushed natural stone or aluminum is formed thereon. In general, a method of applying a resin mixed with a material (hereinafter, referred to as a pattern material) that gives a pattern to a molded product such as flakes, and further laminating and curing a resin containing a reinforcing material such as glass fiber thereon is performed. Have been done. However, the hand lay-up method has low productivity and is not suitable for mass production.

Various methods have been proposed as a patterning method in the FRP press method with good productivity. For example, JP-A-59-108036 discloses a method using an SMC in which a flaky pattern material of 400 to 16 mesh size is dispersed, and JP-A-63-4915 discloses an SMC containing a pattern material.
Method of sequentially charging and stacking MC, glass mat and SMC in a mold, and compressing and molding the same.
No. 5973, a pattern is printed on titanium paper having a large concealing property, a prepreg sheet is prepared by impregnating the printed titanium paper with a thermosetting resin, and the prepreg sheet is placed in a molding die where a pattern is to be provided. The methods used are each proposed.

However, in the method (1), the cost is increased because the SMC containing the expensive pattern material is used up to the back surface of the molded article. In the method (2), the SMC containing the pattern material is used only for the surface layer, and the glass mat is used. Insertion prevents intermingling with the back layer SMC, and a relatively beautiful pattern is developed, but the preparation and insertion of the glass mat requires time and labor, and the glass mat has a small basis weight. When used, the prevention of intermingling of the surface layer SMC and the back layer SMC becomes insufficient, and the use of a material having a large basis weight results in an increase in cost. However, there is a problem that the pattern to be formed is flat and lacks a sense of depth, and it is difficult to exhibit a transparent feeling. Further, since titanium paper is easily broken at the time of molding, there are problems such as limitations on molding conditions.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to solve such a problem, and an object of the present invention is to provide a thermosetting resin having a pattern on the surface capable of expressing a pattern with a sense of depth and transparency. An object of the present invention is to provide a method for producing a molded article made of a conductive resin.

[0007]

According to a first aspect of the present invention, there is provided a method for producing a thermosetting resin molded article having a pattern on a surface, the method comprising the steps of: A molding material and a molding material for a back layer material mainly composed of a thermosetting resin are charged on a molding die, and the stacked molding material for a surface layer material and the molding material for a back layer material are subjected to heat compression molding. A method for producing a thermosetting resin molded article having a pattern on its surface, wherein the molding material for a surface layer material is 3 to 30 parts by weight of a pattern material with respect to 100 parts by weight of a thermosetting resin component, and is polyfunctional. Isocyanate 1 to 15 parts by weight, and polyol 1 to 15
It is characterized by containing parts by weight.

The method for producing a thermosetting resin molded article having a pattern on its surface according to claim 2 (hereinafter referred to as the present invention 2) comprises:
The production method according to the first aspect of the present invention, wherein the surface layer molding material further contains 1 to 10 parts by weight of A-type zeolite or 1 to 30 parts by weight of silica gel based on 100 parts by weight of the thermosetting resin component. It is.

As the thermosetting resin used for the molding material for the surface layer material and the back layer material of the present invention, conventionally known BMC,
A thermosetting resin used for preparing SMC can be used, and examples thereof include an unsaturated polyester resin, an epoxy acrylate resin, and a urethane acrylate resin. In this thermosetting resin, BMC, a low-shrinkage agent, a filler, glass fiber as a reinforcing material according to a conventional method of preparation of SMC,
It is preferable to use the composition in the form of BMC or SMC by adding a curing agent, a release agent and the like.

[0010] In order to improve the transparency of the surface layer of the obtained molded article, a resin used for the molding material for the surface material,
It is preferable to use a filler or the like having a refractive index close to that of glass. In particular, it is preferable to use a filler having a refractive index close to that of glass, and glass powder and aluminum hydroxide are suitable.

[0011] In the present invention, the pattern material used by being mixed into the molding material for the surface layer material may be decomposed by heat or pressure during press molding.
The material, shape, size, etc. are not limited as long as they do not deteriorate, and, for example, as inorganic materials, calcium carbonate, silicon carbide, mica, opal, zirconia,
Examples include finely pulverized products of mineral and metal materials such as mullite and magnesium oxide.

The organic type includes cut or finely pulverized films of films such as polyester, polyethylene, acrylic resin, PVC, polyamide, polycarbonate and PET.

Further, it is optional to use a cut or crushed product such as the outer shell and shell of an aqueous arthropod such as crab and shrimp.

The pattern material may be used as it is in its natural color, or may be used after being colored. As the colorant, commonly used pigments and dyes can be used. This colorant may be mixed with the pattern material and used, or may be colored after being cut or pulverized. It is appropriately selected according to the surface pattern and color tone of the desired molded article.

The amount of the pattern material used is based on 100 parts by weight of the thermosetting resin component used for the surface layer molding material.
If the amount is less than 3 parts by weight, the pattern becomes sparse and inconspicuous. If the amount is less than 10 parts by weight, when forming into a product having reinforcing ribs, the pattern material is gathered at the rib portion and the pattern tends to be dense and dense. Dispersion in the material worsens and the resulting pattern also loses designability and costs increase,
It is limited to 3 to 30 parts by weight, more preferably 10 to 25 parts by weight.

When the size of the pattern material is less than 0.1 mm, the pattern of the obtained molded article is not conspicuous, and when the size is more than 2.5 mm, the dispersion in the BMC becomes poor. The thickness is preferably from 0.1 mm to 2.5 mm because the resulting pattern becomes poor in transparency. In particular, it is more preferable to use a mixture of several different sizes in the range of 0.2 mm to 2.0 mm than to use only a single size for expressing a stone-grained pattern.

The polyfunctional isocyanate and polyol used in the molding material for the surface layer in the present invention are compounded as a thickener for the molding material. It suppresses the mixing, prevents mixing of the molding material for the back layer, and plays a role in uniforming the thickness of the surface layer of the obtained molded article. During the compression molding, the molding material for the back layer mainly flows to form the shape of the molded product.

The above-mentioned polyfunctional isocyanate is a compound having a plurality of isocyanate groups in the molecule, for example, tolylene diisocyanate, polymethylene polyphenyl isocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, Aromatic isocyanates such as (-2-isocyanate-2-propyl) benzene, isophorone diisocyanate,
1,3-bis (isocyanatomethyl) cyclohexane,
Examples include alicyclic isocyanates such as tetramethylxylylene diisocyanate, and linear aliphatic isocyanates such as hexamethylene diisocyanate.

Of the above, aromatic isocyanates are preferred because of their excellent price and reactivity, but for applications where discoloration is not desirable, linear aliphatic isocyanates or alicyclic isocyanates, and heat resistance is important. Alicyclic isocyanates are preferred for applications.

When the amount of the polyfunctional isocyanate is less than 1 part by weight per 100 parts by weight of the thermosetting resin component, the effect of suppressing the fluidity during compression molding of the molding material is insufficient, and exceeds 15 parts by weight. Since pinholes easily occur on the surface of the obtained molded product, the amount is limited to 1 to 15 parts by weight. Among them, 2 to 8 parts by weight is more preferable.

The thermosetting resin component refers to a thermosetting resin used for a molding material, a thermoplastic resin, and a vinyl monomer (usually a styrene monomer) usually used in combination with a thermosetting resin.

The above-mentioned polyol is a compound having a plurality of hydroxyl groups in a molecule, for example, 1,4-butanediol, 2,3-butanediol, 1,1,1-trimethylolpropane, polyoxypropylene glycol , Polyoxyalkylene glycol, hydroquinone hydroxy ether and the like, and polyether polyol, polyester polyol, acrylic polyol, epoxy polyol and the like.

Thermosetting resin component 100 of the above polyol
When the amount is less than 1 part by weight, the thickening effect is not obtained, and when the amount is more than 15 parts by weight, the quality such as hot water is reduced, so that the amount is limited to 1 to 15 parts by weight. Among them, 3 to 10 parts by weight is more preferable.

In order to promote the reaction of the above polyfunctional isocyanate and polyol as a thickener, if necessary,
It is also optional to use a reaction accelerator such as an acid, a base, and various metal compounds. Examples of the reaction accelerator include triethylamine, triethylenediamine, tin octoate, dibutyltin dilaurate, potassium oleate, tin chloride, antimony trichloride, and the like.

As a thickener for the surface layer molding material, in addition to the above polyfunctional isocyanate and polyol, if necessary, magnesium oxide, magnesium hydroxide, and oxide generally used in ordinary thermosetting resin molding materials may be used. It is also optional to appropriately use a thickener such as calcium in combination.

The A-type zeolite or silica gel used for the surface layer molding material of the present invention 2 is blended to remove moisture in the surface layer molding material. If moisture is present in the surface layer molding material, it reacts with the polyfunctional isocyanate, impairing the stability of the surface layer molding material during preparation and storage, and may cause pinholes in the molded product during compression molding. The A-type zeolite or silica gel has an effect of removing water.

The A type zeolite is M ₁₂ (Al
It has a molecular structure of O ₂ ) ₁₂ (SiO ₂ ) ₁₂ (M is a basic cation), and the structure is composed of tetrahedrons of SiO ₄ and AlO ₄ , and is bonded to each other to form a three-dimensional network. Crystal cavities are formed in the crystal lattice, and the pores of the crystal cavities have a performance of absorbing moisture.

As the silica gel, those generally used as drying agents can be used as they are.

Thermosetting resin component 1 of type A zeolite
When the amount is less than 1 part by weight, the effect of removing water is small, and when the amount exceeds 10 parts by weight, the viscosity of the compound increases and kneading tends to be insufficient.
Limited to parts by weight. Among them, 3 to 7 parts by weight is more preferable.

In the present invention 2, when the silica gel is used, the compounding amount per 100 parts by weight of the thermosetting resin component is less than 1 part by weight, the effect of removing water is small, and when it exceeds 30 parts by weight, the viscosity of the compound increases. The amount is limited to 1 to 30 parts by weight because kneading tends to be insufficient. Above all, 5 to 20 parts by weight is more preferable.

As the apparatus used for the heat compression molding of the present invention, a press machine conventionally used for the heat compression molding of FRP can be used as it is. As the molding die, an upper and lower die is preferable. Usually, the upper die is a movable die and the lower die is a fixed die.

As an example of the production method of the present invention, the above-mentioned mold is heated to 80 to 180 ° C., and a molding material for a surface material and a molding material for a back layer are charged on the heated mold and charged. To 30 kg at a pressure of 10 to 120 kg / cm ^2.
After compression molding for seconds to 20 minutes, the mold is opened and the molded product is taken out.

Here, the charge rate of the surface layer molding material to the mold (the ratio of the material area to the area of the mold) is as large as possible when the pattern of the molded article to be obtained is a complete pattern. It is preferred that If the pattern is partial, it is partially charged at the position of the mold corresponding to the site where the pattern is developed.

[0034]

According to the first aspect of the present invention, there is provided a method for producing a thermosetting resin molded article having a pattern on its surface, comprising: a molding material for a surface material which gives a pattern to the surface of the molded article; A method for producing a thermosetting resin molded article having a pattern on its surface, wherein the molding material for the surface layer and the molding material for the back layer material are heated and compression-molded. Wherein the molding material for a surface layer material has a pattern material of 3 to 30 parts by weight, a polyfunctional isocyanate of 1 to 15 parts by weight, and a polyol of 1 to 1 part by weight based on 100 parts by weight of a thermosetting resin component.
Since it is a method characterized by containing 5 parts by weight,
Since the fluidity during compression molding of the surface layer molding material is suppressed, the back layer molding material does not flow to the surface side, and the use of expensive surface layer molding material containing expensive pattern material is small. A uniform thickness of the surface layer is ensured, the molding time can be shortened, and the production cost can be reduced. In addition, since a surface layer having a uniform thickness is secured, a high-design surface pattern having a sense of depth and transparency is exhibited.

The method for producing a thermosetting resin molded article having a pattern on its surface according to the second aspect of the present invention is characterized in that the molding material for a surface material is prepared by further adding A type zeolite 1 to 10 to 100 parts by weight of the thermosetting resin component. Parts by weight, or a method characterized by containing 1 to 30 parts by weight of silica gel, so that the action of the present invention 1 is exhibited and moisture in the molding material is removed by A-type zeolite or silica gel. The stability during storage and storage of the surface layer molding material is improved, and pinholes do not occur on the surface of the obtained molded article.

[0036]

Embodiments of the present invention will be described below. (Examples 1 to 4, Comparative Examples 1 and 2) This example is an example in which a FRP kitchen counter is patterned. The molds and materials used in each example and each comparative example are shown below.

(Molding die) The molding die has a long side of 1600 mm,
A rectangular mold with a short side of 400 mm (the patterned surface was molded with a lower mold) was used.

(Thermosetting Resin Component Used in the Molding Material) The molding materials for the surface layer material and the backing layer material had the following compositions. 70 parts by weight of an unsaturated polyester resin styrene solution (isophthalic acid-based unsaturated polyester resin having a number average molecular weight of about 20,000 dissolved in a styrene monomer concentration of 40% by weight) and a polystyrene resin solution (polystyrene having a weight average molecular weight of about 95,000) 30 parts by weight of a resin dissolved in a styrene monomer concentration of 65% by weight).

(Curing Agent, Filler and Reinforcing Agent Used in Molding Material) Tertiary butyl peroxybenzoate (TBP) was used as a curing agent for 100 parts by weight of the above resin component.
B) 1 part by weight, 200 parts by weight of aluminum hydroxide having an average particle diameter of 10 μm as a filler, and 20 parts by weight of short glass fiber having a length of 3 mm as a reinforcing material

(Other Compounding Agents) The types and amounts shown in Table 1 were used for the thickener, the release agent, the water absorbent and the like.

(Pattern Material) The molding material for the surface layer material has a thickness of 12
A colored PET film of μm was cut into the following size and made into a flake. The colors, sizes, and amounts used are as follows. White: 0.2 mm, 4 parts by weight; 1.5 mm, 4 parts by weight;
2.0 mm, 2 parts by weight. Black: 0.2 mm, 3 parts by weight; 1.0 mm, 3 parts by weight. Gray: 0.5 mm, 2 parts by weight; 1.5 mm, 2 parts by weight.
20 parts by weight in total.

[0042]

[Table 1]

(Preparation of molding material) The compounding ingredients shown in Table 1 were kneaded with a conventionally known BMC production apparatus, and then compressed at room temperature to prepare a molding material having a thickness of 4 mm. It was thickened by holding for a time.

(Molding) In each of Examples and Comparative Examples, a molding material for a surface layer and a molding material for a back layer shown in Table 2 were used.
Heat compression molding was performed under the following conditions, and molded. The upper mold is heated to 145 ° C and the lower mold is heated to 125 ° C. The lower layer is charged with the surface layer molding material (charge rate 100%) and the backing layer molding material (charge rate 80%). The mold is clamped at a final mold clamping speed of 0.8 mm / sec, and 65 kg / cm
After compression molding at ^{2 for} 10 minutes, the mold was opened to obtain a molded product.
In each of Examples and Comparative Examples, molding was performed 10 times, and the surface of the obtained molded article was visually observed. The results are shown in Table 2.

[0045]

[Table 2]

[0046]

The method for producing a thermosetting resin molded article having a pattern on its surface according to the present invention 1 has the above-mentioned structure.
According to the method, the use of a molding material for a surface material containing an expensive pattern material can be used in a small amount, a surface layer having a uniform thickness can be secured, the molding time can be shortened, and the production cost can be reduced. In addition, since a surface layer having a uniform thickness is ensured, a high-design surface pattern having a sense of depth and transparency that cannot be obtained by the conventional technology is exhibited.

The method for producing a thermosetting resin molded article having a pattern on its surface according to the second aspect of the present invention has the above-described structure. According to the second aspect, the effects of the first aspect of the present invention are exhibited and the molding material for the surface layer is produced. Has good stability during storage and storage, and pinholes do not occur on the surface of the resulting molded article.

Claims (2)

[Claims] 1. A molding material for a surface layer material that gives a pattern to the surface of a molded article, and a molding material for a back layer material containing a thermosetting resin as a main component are charged in a molding die, and the superimposed surface layer is charged. A method for producing a thermosetting resin molded product having a pattern on its surface, wherein the molding material for a material and the molding material for a back layer material are subjected to heat compression molding, wherein the molding material for a surface material comprises a thermosetting resin component 100 3 to 30 parts by weight of a pattern material, 1 to 15 parts by weight of a polyfunctional isocyanate, and 1 to 15 parts by weight based on parts by weight
A method for producing a thermosetting resin molded article having a pattern on its surface, characterized by containing a weight part. 2. The molding material for a surface layer material further comprises an A-type zeolite 1 to 100 parts by weight of a thermosetting resin component.
The method for producing a thermosetting resin molded article having a pattern on its surface according to claim 1, characterized in that it contains 10 parts by weight or 1 to 30 parts by weight of silica gel.