JPS6083985A - Clay - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to clay that is less likely to crack when made into a molded product.

The main ingredients are clay, kaolin clay, talc, calcium carbonate, cold water powder, and other inorganic natural minerals, which are used for crafts, etc., and fiber powder, film-forming agents, thickeners,
It is obtained by adding water with mineral oil etc. and kneading it.
It is molded into a desired shape, such as an ornament, dried at room temperature or heated in an oven, and then finished with paint, lacquer, etc., to form a molded product.

However, in molded articles molded using conventional clay, there has been a problem that cracks occur as the molded product dries during or after molding.

There are various causes for the occurrence of such cracks, and some causes can be removed by taking care when manufacturing or molding the clay, but there are also causes such as a decrease in volume due to evaporation of water during drying (of the molded object). It has been extremely difficult to prevent cracks from occurring due to shrinkage.

An object of the present invention is to provide clay that can prevent cracks that occur due to volume reduction (shrinkage of molded bodies) due to water evaporation during drying, which is difficult to prevent with conventional clay as described above. That is.

As a result of various studies to achieve the above object, the inventor of the present invention thought that the above object could be achieved by mixing an additive that satisfies the following conditions into the clay.

■Since clay comes into direct contact with your hands and skin, for safety reasons,
For hygienic reasons, it does not contain solvents, is 10% harmful and has no Hg properties.

■If mixed into clay, it should not be too sticky to facilitate molding, and should not become sticky as it dries.

■If mixed with clay, when overcoating the molded product with paint, lacquer, etc. after molding and drying, it has good adhesion with paint, lacquer, etc., making it easy to apply, and at this time, it is easy to change the base color. It should be a hot color after curing so that it can be hidden.

■Since clay contains a large amount of water, it is water-soluble (including emulsion state) due to its compatibility.

■It has flexibility or elasticity before drying, hardens into a solid after drying, and has good physical and mechanical strength.

■Things that do not react in a way that would cause problems with other clay constituents.

■Those whose pH value is neutral or around it.

■When mixed with clay, it must have good storage stability as a product before molding (storage stability for one year in a sealed state after kneading).

■When mixed with clay, it should reduce yellowing of the molded product after drying and provide good weather resistance.

[Phase] When mixed with clay, it should promote bonding between the clays.

Therefore, as a result of further various studies based on the above considerations, the present inventor found that acrylic resin emulsion is an additive that satisfies the above conditions, and that clay mixed with acrylic resin emulsion causes cracks to occur. It was discovered that molded products that are difficult to mold can be obtained.

The clay of the present invention was made based on the above knowledge,
This clay is made of a mixture of inorganic natural minerals as a main component and mixed with water together with fiber powder, etc., and is characterized by being mixed with an acrylic resin emulsion.

The clay of the present invention will be described below.

The clay of the present invention is characterized in that it is made by adding and mixing acrylic 43 (fat emulsion), and the other components are not particularly different from conventional clay.

That is, the clay of the present invention is mainly composed of inorganic natural minerals, and the inorganic natural minerals - ζ are kaolin clay, talc, calcium carbonate, cold water powder, sericite, etc.
The same material used for conventional clay is used. In addition, additives other than the acrylic resin emulsion added to the inorganic natural mineral include pulp, which is added for the purpose of preventing cracks from forming during the stretching of the clay during molding. Fiber powder such as powder, petrolatum, polybutene, mineral oil such as linseed oil, which is added as LI to prevent the clay from sticking to the skin during molding.
Thickeners such as sodium cellulose glycolate, which are added for the purpose of appropriately adjusting the plasticity of clay during molding, and building agents and dispersants such as vinyl acetate, are added to conventional clay. The following can be selected and used as appropriate.

Therefore, the clay of the present invention is obtained by adding and mixing an acrylic resin emulsion into a mixture containing the above-mentioned inorganic natural mineral as a main component and kneading the above-mentioned various additives with water. Examples of emulsions include emulsions whose main component is an acrylic/styrene copolymer containing styrene, acrylic acid ester, and methacrylic acid in approximately the same weight ratio.
It is commercially available as X-, 533L' (manufactured by Nippon Karhide Kogyo Co., Ltd.). In addition, as the acrylic resin emulsion used for the clay of the present invention, Poncoat EC-
890 (manufactured by Dainippon Ink@), Polysol AP-265
Commercially available products include 0 (manufactured by Showa Kobunshi ■) and Movinyl 860 (manufactured by Hoechst Japan).

The concentration of the acrylic resin solid content in the acrylic resin emulsion is usually about 35 to 55% by weight, and the preferred amount of the acrylic resin emulsion with such a concentration is 7 to 20% by weight in the clay of the present invention. %. If the amount of acrylic resin emulsion used is less than 7% by weight, the effect of its addition will not be sufficient, and
If it is more than % by weight, the texture of the clay will lack the inorganic feel (stone texture).

The preferred amount of the acrylic resin emulsion is such that the solid content of the acrylic resin is 6 to 20 parts by weight based on 100 parts by weight of the inorganic natural mineral that is the main component of the dog.

In addition, in the clay of the present invention, by adding mineral n11 together with the acrylic resin emulsion, it is possible to prevent the acrylic resin emulsion from sticking to the skin of the hands during the molding of the clay, and also to prevent the clay from slipping and stretching. At the same time as drying 11.1, it is possible to prevent dust, dirt, etc. from adhering to the surface.

The clay of the present invention, like conventional clay, can be produced by kneading the raw materials described in -5 with water at a predetermined ratio, and the preferable ratio of the usage of the raw materials is as follows. It is usually manufactured completely sealed in a plastic bag.

Part by weight Inorganic natural mineral 100 Acrylic resin solid content 6-20 Fiber powder 0.5-1 Mineral oil 0.3-3 Film forming agent 0.5-1 Thickener 1-5 Dispersant 0.5-2 Water 50 to 150 In the clay of the present invention, among the above raw materials, the film forming agent, thickener, mineral oil, and dispersant can be omitted as necessary.

As mentioned above, the clay of the present invention is one in which an acrylic resin emulsion is added and mixed as a component, and when it is dried after being molded into a desired shape, the resulting molded product does not crack or cracks do not occur. Moreover, this molded product has little yellowing and good weather resistance, has good separation during molding, has appropriate adhesiveness and plasticity, and has good bonding properties between clays. It is easy to mold with
In addition, it has good adhesion with paints, lacquers, etc., is easy to finish with a top coat, and has excellent storage stability in a sealed state as a molded product. be.

Examples of the present invention and test examples demonstrating the effects of the present invention are shown below.

Practical Examples 1 to 3 Nikabul RX-533L manufactured by L1 Karhide Kogyo@ was used as an acrylic resin emulsion, and each component was thoroughly kneaded according to the formulation shown in the table below, and clay (products of the present invention 1 to 3) was prepared. was manufactured.

Incidentally, Nikazol RX-533L contains acrylic/styrene in approximately the same weight ratio of 11! It is a white emulsion with a solid content of 45% and a pH of 8 to 9. In addition, as an inorganic natural mineral, a mixture of takuru and kaolin glyceryl-1-clay, etc., as a film-forming agent, hinyl acetate-based powder, as a thickener, cellulose glycol-1-thorium, White vaseline (Lantco "fi, M) was used as the mineral oil.

Test Examples Clay of the present invention manufactured in Examples 1 to 3 (Invention products 1 to 3)
3) were thoroughly kneaded and then stretched onto a wooden board (10 cm x 20 cm) coated with epoxy resin to a thickness of 2 ff 1 m using a round bar. After drying this by leaving it in a room at room temperature for 3 days, the presence or absence of cracks and the stone texture were evaluated.

In addition, in order to clarify the effect of adding the acrylic resin emulsion, the same procedure as in Examples 1 to 3 was carried out except that the acrylic resin emulsion was not added and the amount of mineral oil added was changed to 0.5 parts by weight. A tennendo (comparative product) was manufactured and tested in the same manner as inventive products 1 to 3.

The results are summarized in the table below (not shown).

In addition, the reason why we used a wooden board coated with epoxy resin in this test example was to prevent cracks from forming when forming the bowl because the inner surface of the core material is sealed like a beer bottle and the outer surface is in direct contact with the outside air. This is because it is assumed that it will be used under harsh conditions where it is easy to break.

The results of the above tests show that the clay of the present invention to which an acrylic resin emulsion is added has a remarkable effect on preventing the occurrence of cracks due to drying after molding.

Patent Applicant Tamio Yamane Kagaku Kogyo Co., Ltd. Procedural Amendment 21 1. Indication of the case Patent Application No. 1982-192012 2. Title of the invention 3. Person making the amendment Relationship with the case Patent Applicant Tamio Yamane Kagaku Kogyo Co., Ltd. Kagaku Kogyo Co., Ltd. 4, Agent No. 29 Akasaka 9-chome, Minato-ku, Tokyo [) Pacific Nogizaka 601 January voluntary amendment (amendment of application 19J1 request for examination 11.5) 6, 0° of the invention of the specification subject to amendment F type explanation Q month I drama.

7. Contents of correction

Claims (2)

[Claims] (1) In clay made of a mixture of inorganic natural minerals as the main component and water added together with fiber powder, etc.
A clay characterized by adding and mixing an acrylic resin emulsion. (2) The clay according to claim (1), wherein the acrylic resin emulsion is mixed in an amount of 6 to 20 parts by weight as acrylic resin solid content based on 100M of inorganic natural mineral.