JPS5884718A - Manufacture of silicone resin matrix - Google Patents

Abstract

PURPOSE:To improve the durability of silicone resin and to increase times of molding by using the silicone resin mixed with unsaturated polyester resin polymerization inhibitor. CONSTITUTION:Silicone resin 3 where unsaturated polyester resin polymerization inhibitor (0.1-0.3%) (such as hydroquinone) is added is injected into the frame 2 providing a master mold 1 composed of wood, plaster, clay, etc. and cured by room temperature or heating, then released from the mold to obtain a silicone resin matrix 4. Styrene monomer, prepolymer and organic peroxide comprising unsaturated polyester resin is prevented from penetrating into a silicone resin matrix and polymerized. It is possible to restrict deterioration of the silicone resin matrix and increase remarkably molding times of silicone resin matrix.

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to improve the resistance of a silicone resin, which is a component of a matrix for molding unsaturated polyester resin products, and to increase the number of times the mold is made.

Generally, a mold made of silicone resin is used as a matrix when molding unsaturated polyester resin into a desired shape. This silicone resin gradually deteriorates as the unsaturated polyester resin is repeatedly molded, typically 50 times, in the case of a silicone resin matrix held by a backing film for making polyester decorative laminates. Although it depends on the backing film used, the limit is 10 to 20 times.

In order to increase the number of times the silicone resin matrix lasts, methods such as applying a barrier coat with a 7-layer resin, etc., and allowing the silicone resin to rest at intervals between uses of the silicone resin matrix are used. Despite the problems of workability and high cost, it has not been very effective. In particular, when a barrier coat is used, the fine glossy state of the surface is damaged, making it unsuitable in terms of reproducibility.

The biggest cause of silicone resin deterioration is that during unsaturated polyester resin molding, unsaturated polyester components such as alstyrene monomer, prepolymer, and organic peroxide, which is a reaction catalyst, are mixed into the silicone resin, which is a component of the matrix. This is because the polymer penetrates into the silicone resin, polymerizes inside the silicone resin, and the polymer accumulates in the silicone resin. Due to the accumulation of this polymer, the silicone resin itself loses its rubber-like elasticity and becomes hard and brittle, making it difficult to release it from the unsaturated polyester resin.

The inventors of the present invention have conducted intensive research to solve this problem, and have found that it is possible to prevent the styrene monomer and prepolymer, which are components of unsaturated polyester resin, from penetrating into silicone resin from polymerizing. They came to the conclusion that this is the most efficient method, and completed the present invention.

To explain the present invention in detail below, the present invention involves kneading a polymerization inhibitor for the unsaturated polyester resin into the silicone resin when creating a matrix made of silicone resin for molding the unsaturated polyester resin. Heat and harden silicone m fat,
Or, it is cured at room temperature to form a matrix, and the polymerization inhibitor inhibits the polymerization of the styrene monomer and prepolymer in the unsaturated polyester resin that have penetrated into the silicone resin during molding of the unsaturated polyester resin. do.

This method of manufacturing a silicone resin matrix is characterized by increasing the resistance of the silicone resin.

The present invention will be explained in more detail with reference to the drawings.

First, the case of a silicone resin matrix for molding unsaturated polyester resin by ordinary casting will be explained. First of all
As shown in the figure, a prototype (1) made of wood, plaster, clay, plastic, metal, etc. is used as a formwork (1) made of a wooden frame, metal frame, etc.
Place it in 2 (.Next, place it in the mold-making silicone resin (31).
After kneading a polymerization inhibitor for unsaturated polyester resin into the mold and removing air bubbles and volatile matter from the silicone resin by vacuum degassing, the silicone resin is poured into the mold and cured at room temperature or by heating. By releasing the mold from the original mold, a silicone resin matrix (4) to which a polymerization inhibitor of unsaturated polyester resin has been added is obtained.

The mold-making silicone resin used here is room temperature curing type RTV, which is generally used for mold-making, or 60'~
LTV, which rapidly undergoes a crosslinking reaction and cures when heated at about 15°C, can be used as a two- or three-component type.

In addition, quinones, hydroquinones (
There are many polyhydric phenols), phenols, etc., but the most representative ones are hydroquinone, mono-1-butylhydroquinone, benzoquinone, and 2.5-diphenyl-
Para-benzoquinone, 2.5-di-t-butylhydroquinone, methylhydroquinone, 2.5-diacetoxy-para-benzoquinone and the like are excellent.

The amount added is 01-03% based on silicone resin.
It can be added up to a certain extent, and the effect is better as the amount is increased, but from the viewpoint of inhibiting the curing of the unsaturated polyester resin that becomes the product, it is desirable that it be at most 0.3% or less. Furthermore, these polymerization inhibitors may be dissolved in a solvent and then kneaded into the silicone resin if necessary, but the solvent must be volatilized before the silicone resin is cured.

Next, to explain the silicone resin film for making polyester cosmetics, first, as shown in Figure 2, a manuscript (5) made of wood or plastic is placed, and then unsaturated polyester resin is applied to it in the same manner as in Figure 1. A silicone resin (6) mixed with a polymerization inhibitor is applied to the document, and a transparent plastic film (8) is placed thereon. The polymerization inhibitor for the silicone resin and unsaturated polyester resin used here may be the same as the polymerization inhibitor for the silicone resin and unsaturated polyester resin described above, but the silicone resin is used for the unsaturated polyester resin when making the polyester decorative board. It is desirable that it be transparent so that the presence of air bubbles can be confirmed from above when removing air bubbles inside or at the interface of the resin layer. The transparent plastic film may be any polyester film, vinylon film, polyolefin film, etc., but as described above, it must be transparent like the silicone resin. This film is preferably coated with an alkyl-modified silicone resin-based or alkyl titanate-modified silicone resin-based primer (7) that strengthens the adhesive force with the silicone resin.

Next, the silicone resin is cured at room temperature or by heating, the silicone resin is integrated with the film, and the mold is released from the original, thereby creating a silicone resin matrix (9) for producing a polyester decorative board.

What both production methods have in common is that a polymerization inhibitor for unsaturated polyester resin is added to the silicone resin, and the method may be exactly the same.

1 of unsaturated polyester resin produced as above
The effects of the silicone resin matrix for molding unsaturated polyester resin products to which a co-inhibitor has been added are as follows.

Since a polymerization inhibitor for unsaturated polyester resin is added to the silicone resin, it prevents monomers and prepolymers that penetrate into the silicone resin matrix during unsaturated polyester resin molding from polymerizing inside the silicone resin. This can prevent deterioration of the silicone resin matrix. This makes it possible to significantly increase the number of times the silicone resin matrix is used, and to reduce product costs.

Next, examples of the present invention will be shown.

[Example 1] Transparent silicone resin KE-106L cured by addition polymerization after sandering natural wood veneer and finishing painting.
After stirring and defoaming to remove the solvent, a 10% acetic acid ethyl ester solution of t-butylhydroquinone (manufactured by Kanto Kagaku ■) was added to a TV (manufactured by Shin-Etsu Chemical Co., Ltd.) at 2%. Pour Primer A (Shin-Etsu Chemical Co., Ltd.
Stretched polyamide films treated with the above-mentioned polyamide film (manufactured by Nippon Steel & Co., Ltd.) were stacked together, and the film was evenly smoothed using a roller, and then placed in an open atmosphere at 60°C (7'"l) for 4 hours to harden the silicone resin, and then separated. A matrix film was obtained by molding.

For comparison, a matrix film to which no t-butylhydroquinone solution was added and a matrix film to which 5% t-butylhydroquinone solution was added were also prepared in the same manner. Polyester decorative boards were prepared using these three types of matrix films and their shape retention properties were compared. (
Each mold was repeated 100 times. ) The uneven luster of the product occurs because the silicone resin surface becomes rough due to deterioration.

This is due to the addition of too much uncured &X t-butylnohydroquinone.

As is clear from the above results, the addition of a polymerization inhibitor to the polyester resin greatly improved the shape retention performance.

[Example 2] Silicone resin K B-160OR, T is cured by addition polymerization after using a wooden carved animal as a prototype and setting it in a mold.
V (manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed with 3% methylhydroquinone (manufactured by Kanto Kagaku Co., Ltd.), defoamed, poured into the mold, and cured at room temperature to obtain a silicone resin matrix. .

For comparison, a silicone resin matrix to which no methylhydroquinone was added was also created at the same time.

Polyester resin molded products were repeatedly molded using these two types of molds, and their temperature and mold retention performance were compared.

(Results) For the silicone resin master mold to which methylhydroquinone was not added, smearing began to become noticeable from about the 30th test, and at about the 50th test, breaks occurred in the silicone resin film at sharp edges and the like.

On the other hand, with the silicone resin matrix to which methylhydroquinone was added, no abnormality occurred even after 100 baths, and 200 baths were easily carried out.

[Brief explanation of the drawing]

The drawings are explanatory drawings showing an example of the method of the present invention. Fig. 1 is an explanatory drawing showing the manufacturing process of a silicone resin matrix for casting, and Fig. 2 is an explanatory diagram showing the manufacturing process of a silicone resin matrix for manufacturing a polyester decorative board. It is an explanatory diagram showing a process. (1)... Prototype (2)... Formwork (32
... Silicone resin (4) ... Silicone resin matrix (5) ... Manuscript (6) ... Silicone resin (7) ... Primer (8) ... Plastic film (9) ...・Silicone resin matrix patent applicant Toppan Printing Co., Ltd. Representative Kazuo Suzuki 11-72

Claims (1)

[Claims] (1) A silicone resin matrix characterized by increasing the resistance of the silicone resin by adding an unsaturated polyester polymerization inhibitor to the silicone resin when manufacturing the silicone resin matrix for unsaturated polyester resin molding. Mold manufacturing method.