JPH0238351A - Granitic molded thermoplastic resin product - Google Patents

Abstract

PURPOSE:To improve workability, such as cutting, and appearance of worked products by containing a dispersed inorganic filler and heat-resistant colored synthetic resin particulate substance in polymethyl methacrylate resin. CONSTITUTION:About 100-300 pts.wt. inorganic filler, such as aluminum hydroxide, and about 0.5-40 pts.wt. heat resistant colored synthetic resin particulate substance (having 0.1-3.0mm particle diameter), such as polyester, are homogeneously mixed with 100 pts.wt. polymethyl methacrylate resin and the resultant mixture is press formed by heating at about 180-200 deg.C temperature under about 10-100kg/cm<2> pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a granite-like thermoplastic resin molded product, which is used, for example, as a top plate of a bathroom vanity, a countertop of a system kitchen, and the like.

Conventional technology Conventionally, granite-like resin artificial stones have been manufactured using unsaturated polyester resin or acrylic resin with excellent weather resistance and beautiful appearance as a matrix, and inorganic substances such as aluminum hydroxide and magnesium hydroxide are used in the matrix. A molded article containing a filler and thin crushed stone particles of natural stone such as black stone, red stone, curb stone, etc., uniformly dispersed therein is known (for example, JP-A-59-111969).

Problems to be Solved by the Invention However, since conventional artificial stone molded products such as those described above use crushed natural stone particles with high hardness as elements for imparting granite-like patterns, cutting and machining are not required in the resulting molded product. There were problems in terms of properties and poor processability. Furthermore, in manufacturing, since the specific gravity of the crushed stone particles is considerably larger than that of the matrix, the crushed stone particles tend to settle during the mixing stage, making it difficult to manufacture molded products with a uniform granite-like external pattern. There was a problem that. Furthermore, if the surface of the molded product is scratched during use, it should be repaired (if surface abrasive treatment such as sanding is applied, the difference in hardness between the matrix resin and the crushed stone particles will cause the crushed stone particles to scratch the surface). There was also the problem that the surface protruded and it was difficult to finish it to a smooth surface.

An object of the present invention is to provide a thermoplastic resin molded article as an artificial stone having a beautiful granite-like appearance that can solve the above-mentioned problems.

Means for Solving the Problems The main purpose of the present invention is to use heat-resistant colored resin granules instead of conventional natural stone as an element for imparting a granite-like pattern.

That is, the present invention uses a polymethyl methacrylate resin as a matrix, and for 100 parts by weight of the resin, 100 to 300 parts by weight of an inorganic filler and 0.00 parts by weight of heat-resistant colored synthetic resin particles. The gist is a granite-like thermoplastic resin molded product characterized by containing 5 to 40 parts by weight dispersed therein.

In the resin molded article according to the present invention, the polymethyl methacrylate-1 resin used as the matrix is a homopolymer of methyl methacrylate, or a methyl methacrylate with 70 or more doubles, and acrylic ester, methacrylic ester, One or two other vinyl polymers copolymerizable with methyl methacrylate
Examples include polymers in which more than one species is copolymerized.

Inorganic fillers added to the resin component include inorganic powders such as aluminum hydroxide, magnesium hydroxide, calcium carbonate, and silica. In particular, aluminum hydroxide has a refractive index close to that of acrylic resin. Therefore, it can be suitably used because it has both transparency and concealability, and can give a deep appearance. The amount of the inorganic filler added is determined in order to obtain the characteristic transparency of natural stone.
It is necessary to set the amount in the range of 100 to 300 parts by weight per 100 parts by weight of the resin component. This addition amount is 10
If it is less than 0 parts by weight, the hiding power will be poor and the transparency will be too strong, making it impossible to express a profound feeling.

On the other hand, when it is added in a large amount exceeding 300 parts by weight, the transparency is lost and a deep appearance cannot be obtained. A particularly suitable range of addition amount is 150 to 2
The amount is about 50 parts by weight.

Furthermore, the synthetic resin used for the colored resin granules must have heat resistance to the extent that it will not melt unnecessarily during heating (approximately 180 to 200°C) during molding. That is, if excessive melting occurs during molding, flow will occur in the patterned portions, impairing the granite-like appearance. Therefore,
As the resin, it is preferable to use one having a heat deformation temperature of 180° C. or higher. Preferred examples of specific resin types include thermoplastic resins such as polyester, polyimide, and polysulfone, and thermosetting resins such as melamine and phenol.

The amount of the colored resin granules added as a pattern imparting element is as follows:
0.5 to 4 per 100 parts by weight of matrix resin component
It should be in the range of 0 parts by weight. If it is less than 0.5 part by weight, the desired shading pattern will appear in a sparse and scattered pattern, and a natural granite-like appearance cannot be obtained. Also, 4
If it is contained in an excessive amount exceeding 0 parts by weight, the appearance of the molded product will lose its transparency and become dark-colored, resulting in a decrease in beauty. The most suitable dispersion content is approximately 1 to 20 parts by weight per 100 parts by weight of the matrix resin component.
Parts by weight range.

Furthermore, the size of the colored resin granules used also has an important effect on the appearance and strength characteristics of the molded product.

A suitable particle size range is about 0.1 to 3.0 m.

That is, if the particle size is less than 0.1#, the pattern of shading becomes unclear. On the other hand, if the length exceeds 360 m, there will be areas where the proportion of the volume occupied by colored resin particles per unit area becomes extremely large, resulting in defects such as decreased rigidity and strength of the molded product or non-uniformity. do. Particularly preferably, particles having a particle size of about 0.5 to 2.0 mm are used.

The production of granite-like thermoplastic resin molded products according to this invention includes:
Similar to the conventional product, the above materials are uniformly mixed in a predetermined blending range, and heated at 180 to 200°C.
This is done by press molding at a pressure of 0 to 100 kg/cd to form a plate or other shape.

Incidentally, the granite-like resin molded article according to the present invention may contain, in addition to the above-mentioned compounded materials, an appropriate coloring material, if necessary. Depending on the tone of the coloring material used,
For example, it can be given the appearance of a red formation, a blue formation, a black formation, or the like.

Example Examples 1-6, Comparative Examples 1-2 The following materials were used as compounding materials.

[Matrix resin]

Polymethyl methacrylate resin (product name "Sumipex B" manufactured by Sumitomo Chemical Co., Ltd.) [Inorganic filler] Aluminum hydroxide (product name "Hisilite Hloo")
"manufactured by Showa Denko Co., Ltd.) Average particle size 20 to 70 μm [Heat-resistant color resin granules] A: Black polyester resin particle size 1.0 mm B: Black polyester resin particle size 2. Omm C: Brown phenolic resin particle size 1.5m [Coloring material] Red coloring material (product name: "Diamond Resin Red H3J, manufactured by Mitsubishi Chemical Industries, Ltd.") The proportions of the above compounding materials were varied as shown in Table 1. , and added a small amount of lubricant (dioctyl phthalate) to the Henschel mixer and mixed for 7 minutes.Then, the resulting mixture was mixed in L 400 m x W 4
It was filled into a press molding flat mold of 00 m x H12 m.

In this flat molding mold, a lower board made of a mirror plate is placed within the frame of a framed board having a raised stopper frame on the periphery, with a lower cushion material interposed therebetween, and a raised plate is placed on the periphery of the lower board. After arranging a 12# enclosure frame, it was filled with the above mixture, and an upper glazing board and an upper cushion material were placed on top of it.

Then, the flat mold filled with the above mixture was inserted between the hot discs of a multi-stage press machine, and the temperature was gradually raised while applying pressure from above and below at a pressure of 10 kg/cd. After heating at a temperature of 180 ° C. for 40 minutes, Further, the molded product was cooled while continuing to be pressurized at a pressure of 80KFI10r to obtain samples of various molded products.

Comparative example 3 Instead of the colored resin granules described above, A stone-like molded product was obtained.

The appearance of the various samples obtained in Examples 1 to 6 and Comparative Examples 1 to 3 was observed, and the similarity in transparency and shading pattern was evaluated in comparison with natural granite. The ease of machining was investigated by cutting with. In Table 1, those with good approximation to natural granite and good machinability are marked O, and those with poor approximation and poor machinability are marked X.

After the same table, the observational impressions of the appearance of each sample were explained.

[Margin below]

The procedure was the same as in Example 1, except that black colored angar stone, dark green colored angar stone, particle size 1#, and particle size lInIn were used (exterior impression). It had an appearance similar to a white formation stone.

Example 2 It had an appearance extremely similar to natural granite in terms of transparency, depth, and shading pattern.

Example 3...Although the transparency was poor, it had an appearance similar to black granite.

Example 4 It had an appearance extremely similar to red formation stone in terms of transparency and shading pattern.

Example 5 It had an appearance extremely similar to natural granite in terms of transparency, depth, and shading pattern.

Example 6 It had an appearance extremely similar to natural red granite in terms of transparency, depth, and shading pattern.

Comparative Example 1 The transparency was too strong, the shading patterns were sparsely scattered, and the sample did not have a granite-like appearance.

Comparative Example 2... The transparency was extremely poor, the shading pattern was too strong, and it did not have a granite-like appearance.

Comparative Example 3 It had an appearance similar to black granite in terms of transparency and shading pattern.

Effects of the Invention By using acrylic resin as the matrix resin, the granite-like thermoplastic resin molded product according to the present invention not only realizes the inherent weather resistance and material transparency, but also has a predetermined amount of inorganic filler. The combination of the concealing effect created by the blending of , and the effect of imparting a mottled pattern created by blending a predetermined amount of colored resin granules as a pattern-forming element creates a beautiful stone with depth, surface transparency, and shading patterns similar to those of natural granite. It can be made into something. In addition, the use of colored resin granules as pattern-imparting elements makes cutting and cutting easier, compared to conventional crushed natural stone particles.
It has good machinability such as cutting, and even if the surface is scratched, it can be easily restored to a smooth surface by polishing such as sanding. Furthermore, by using the heat-resistant colored resin granules, the beautiful natural granite-like pattern can be produced using ordinary molding methods, and the material can be uniformly dispersed in the matrix resin when mixing the materials. Since it has good properties and does not settle and become unevenly distributed during molding, it is possible to easily produce a molded product having a uniform external pattern with little disturbance of the pattern throughout.

that's all Procedural amendment Mr. Kunio Kogawa, Commissioner of the Patent Office 1. Display of incident 1988 Patent Application No. 103671 2, Title of Invention Granite-like thermoplastic resin molded product 3. Person who makes corrections Relationship with the incident address name

Claims (2)

[Claims] (1) Polymethyl methacrylate resin is used as a matrix, and 100 to 100 parts by weight of inorganic filler are added to 100 parts by weight of the resin.
300 parts by weight, and 0.5 parts of heat-resistant colored synthetic resin granules
A granite-like thermoplastic resin molded article, characterized in that it contains ~40 parts by weight dispersed therein. (2) The colored synthetic resin granules have an average particle size of 0.1 to 3.0.
The granite-like thermoplastic resin molded article according to claim 1, which is mm.