JPS613714A - Manufacture of silicone rubber molded article - Google Patents

Abstract

PURPOSE:To obtain simply and freely an excellent molded article, by a method wherein a silicone rubber material having plasticity at a normal temperature and containing a vulcanizing agent is molded and the molded article is dipped into the high-temperature water heated at a specific temperature. CONSTITUTION:A silicone rubber material having plasticity at a normal temperature is obtained by kneading a silicone rubber base by adding a vulcanizer and a filler and an additive for reinforcement which are added according to necessity, which is molded into a desirous shape and the silicone rubber material forming a milded article is made to cure by vulcanizing the same by loading the obtained molded article into the high-temperature water heated up to the temperature of 90-100 deg.C. With this construction, a silicone rubber molded article in a desired shape can be manufactured simply at low cost, and is extremely profitable for manufacturing a component and parts making use of excellent properties and the other characteristics which are possessed by the silicone rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a 7-licon rubber molded product.

Conventionally, in molded products made of silicone rubber, room temperature curing liquid silicone rubber or heat vulcanization type silicone rubber has been used as a raw material. A molding material made of heat-vulcanized silicone rubber is generally referred to as silicone rubber #v77p and is usually reinforced with methyl vinyl polysiloxane.

It is made by blending silica, quartz powder, pigment, vulcanizing agent, etc., and it varies depending on the type of polysiloxane and the type of vulcanizing agent, but when a molded product with a thickness of, for example, zO is put in a press machine, Vulcanization is carried out by heating under a pressure of 8 to 5 H7 cm2 to a high temperature, for example, at a temperature of 120 to I Fr QC degrees or higher.

This makes it possible to obtain a silicone/vim molded product.

However, with this method, equipment such as a press machine is required for vulcanization.As the thickness of the 1g shape increases, the heating temperature must be lowered to fully vulcanize the entire material. I can't do it.

Furthermore, since the heating temperature is high and the pressure is applied, the shape of the molded product may change during the vulcanization process, making it difficult to obtain a molded product of the desired shape.

There is also a known method of heating in an oven, but
With this method, there is a strong tendency for the molded product to become sticky due to lack of ℃ vulcanization due to six-sided defects, and as a result, post-processing such as powdering is required. .

On the other hand, when used as a liquid silicone rubber material that cures at room temperature, the curing time is very long, 10 to 24 hours, and the mixing and defoaming of the rubber liquid is required, and the reprocessing time for the mixed material is short. It has disadvantages such as not being able to be stored in a vacuum.

The present invention has been made in view of the above circumstances, and its object is to provide a method for manufacturing silicone rubber molded products that allows excellent molded products to be obtained extremely easily and freely.

A feature of the present invention is that a silicone rubber material that is plastic at room temperature and contains a vulcanizing agent is molded, and the molded product is immersed in high-temperature water heated to a temperature of 90 to 100°C. The point is to vulcanize the silicone rubber material of the molded product.

The present invention will be specifically explained below.

In the present invention, for example, a vulcanizing agent and optionally a vulcanizing agent are added to a silicone rubber base made of a polysiloxane polymer containing vinyl groups in an o, oi-i weight percent, preferably O01 to 0.7 weight percent. By adding and kneading reinforcing quartz powder, fillers such as atomized concrete, pigments, and other additives, a silicone rubber material that is plastic at room temperature is obtained, which is then molded into the desired shape. The obtained molded product is placed in high-temperature water heated to a temperature of 90 to 100°C, for example, boiling water, and boiled for several minutes to 10 minutes to vulcanize the silicone rubber material forming the molded product. The silicone rubber molded product is thereby manufactured.

In the above, the silicone rubber material is a silicone rubber base that is usually called low temperature curing silicone and is vulcanized at a temperature of about 115 to 150°C when a standard amount of vulcanizing agent is added. A larger amount of vulcanizing agent, such as 2,4-dichlorpenzoyl peroxide, is added than the standard amount. The amount of the vulcanizing agent added here is preferably at or close to the effective limit amount.

"Effective limit amount" refers to the amount at which the actual vulcanization start time will not be shortened even if a larger amount of the vulcanizing agent is added. It means the time until the saturation torque reaches the value of 10 inches in the vulcanization curve of Zam, as measured by ``Type ``.

〃The amount of curing agent added is determined in relation to the vulcanization temperature, vulcanization time, etc. Since vulcanizing agents are relatively expensive, it is generally the minimum amount that will result in sufficient vulcanization. Alternatively, an amount slightly higher than this is considered to be the standard addition amount. If you add more vulcanizing agent than this standard system, the amount added will be below a certain limit! Then, the vulcanization start time becomes shorter as the amount added increases. However, if the amount added exceeds this limit amount, even if more vulcanizing agent is added, the vulcanization start time will not be shortened as much as before. This limit amount is referred to as the "effective limit amount" in the present invention.
It is called. This amount is usually 1.3 times or more the standard addition amount.

By setting the amount of the vulcanizing agent added to the above effective limit amount or a value close to this, sufficient vulcanization can be achieved at a significantly lower temperature than when the vulcanizing agent is added at the standard amount. is possible, and the time required for vulcanization does not need to be so extended. Therefore, the vulcanization temperature is usually 1
By using the effective limit amount of vulcanizing agent or an amount close to this, sufficient vulcanization can be performed in a few minutes at a temperature of 90 to 100°C for solicon vim paste, which is said to be at a temperature of about 15 to 150°C. You can get something.

Since the method of the present invention produces a soricone rubber molded article as described above, the following effects can be obtained.

In other words, since the silicone rubber material used has plasticity at room temperature, it can be used as is for molding operations without requiring special consideration, and molded products can be easily formed by hand. Therefore, molded products with extremely free shapes can be obtained.Furthermore, since vulcanization does not occur even if left at room temperature, it is possible to mold the molded product again even after a long period of time has elapsed. .

In addition, since vulcanization is performed by immersion in high-temperature water, there is no need for special equipment or instruments as in the past.
Extremely simple and without dangerously high temperatures or pressures,
Sufficient vulcanization can be achieved in a relatively short time. Moreover, the surface of the molded product obtained after vulcanization does not become sticky.

In this way, while the temperature is lower than normal,
Sufficient vulcanization can be achieved without applying a lot of pressure because the vulcanization is heated thoroughly by immersing water in high-temperature heat medium, which has a large specific heat. Therefore, the main requirements are that the thermal capacity of the heating medium to the molded object to be vulcanized is sufficiently large, and that the heating medium is liquid so that it can sufficiently contact the entire surface of the molded object, regardless of its shape. It is thought that it is broken for a reason.

Therefore, according to the present invention, a silicone rubber molded product of a desired shape can be manufactured extremely easily and at low cost, and silicone rubber has excellent rL, such as heat resistance, cold resistance, and temperature resistance. It is extremely advantageous for manufacturing members, parts, etc. that utilize the properties of elasticity, electrical insulation, chemical resistance, water resistance, and other properties that are not available at low cost. In addition, it is tasteless and odorless and harmless to humans and animals, and as mentioned above, no special equipment is required, making it easy to manufacture appliances, toys, and other parts of desired shapes at home, school, and other places. is possible.

Preferred embodiments of the present invention will be described below, but the present invention is not limited thereto.

Example 1 Silico-y-! made of a polysilicon polymer having a vinyl group content of 0.8% by weight! Mujes l"8H41J
(Manufactured by Tomu Silicone Co., Ltd., standard addition amount of vulcanizing agent 1.5
50 parts by weight of quartz powder was added to 100 parts by weight (% by weight), and further 2. ．． A silicone rubber material was obtained by adding 2.5 parts by weight of a vulcanizing agent (50% proprietary silicone is -st) consisting of 4-, 'chlor-4-zoylpero-chloride, and mixing the mixture.

The silicone rubber material has a groove-like shape and has enough plasticity to be easily deformed by a person's hands and fingers, and can be molded into any desired shape.

About 11 pieces of this silicone rubber material are removed by hand.
“I made a molded product, immersed it in hot water boiling at a temperature of 100C, boiled it for 5 minutes, and vulcanized it. There was no lumps on the surface and it was fully vulcanized. A silicone rubber molded article with good properties could be obtained.

When the physical properties of the rubber of the molded product obtained here were measured,
Hardness 39. The tensile strength was 4 fi 117 cm2 and the elongation was 550 inches.

Example 2 A silicone rubber material was obtained in exactly the same manner as in Example 1, except that the amount of the vulcanizing agent added was 2 parts by weight. This silicone rubber material was putty-like and easy to mold. Further, when the same vulcanization treatment as in Example 1 was performed, sufficient vulcanization was achieved and an excellent silicone rubber molded product was obtained. The physical properties of the rubber of this molded product are hardness of 37, tensile strength of 40 and 9/9.
Crn2. The elongation rate was 600%.

Example 8 The content ratio of vinyl groups is 0.1! Quantity of polysilicone/silicone rubber base made of polymer rsH-55UJ
(Manufactured by Tou Silicone Co., Ltd., standard addition of vulcanizing agent,
100 parts by weight (1.8% by weight) and 2.5 parts by weight of the same vulcanizing agent as in Example 1 were added and kneaded to obtain a silicone rubber powder. This silicone rubber molding had a groove shape and was easy to mold. Further, when the same vulcanization treatment as in Example 1 was performed, sufficient vulcanization was achieved and an excellent silicone rubber molded product was obtained. The physical properties of the rubber of this molded product are hardness 40. Tensile strength 107 kg/cm2. Growth rate 700
%Met.

Example 4 A silicone rubber material was obtained in exactly the same manner as in Example 3, except that the amount of the vulcanizing agent added was 8 parts by weight. This silicone rubber material was putty-like and easy to mold. Further, when the same vulcanization treatment as in Example 1 was carried out, sufficient vulcanization was achieved and an excellent silicone rubber molded article was obtained. What are the physical properties of the rubber in this molded product?

Hardness 87. Tensile strength'il! 105 Ay/cm2. The elongation rate was 800%.

-I' Continuation Supplement iF, Book (method) Showa 5q (r
1 o month 2 II Mr. Manabu Shiga, Commissioner of the Patent Office ('1 Indication 1981 Patent Application No. 123805 2 Name of the invention, . . . Process for manufacturing lean rubber molded products (, 1ili tl 17, relationship with sweat Ino 1. 1.1F license applicant.

I Place: Aichi prefecture name book 14 cities, Naka-ku, T-dai IT, +1.
+', 'I' No. 1121 II Name: Secret plan item - R1 business stock association 5, Sodeichi order [4-I (issued iX 11) 1985!
I J] 25 B, the light of Supplement 11 Contents of the full text of the specification 7゜Extraction As attached to the application for the first time; As shown in the engraving appendix of the J specification (no change in content) Procedural amendment (voluntary) Showa November 13, 1959 Commissioner of the Japan Patent Office Manabu Shiga 1, Indication of the case Patent Application No. 123805/1982 2, Name of the invention Method for manufacturing silicone rubber molded products 3, Person making the amendment Relationship to the case Patent applicant Address: 5-21-11 V Chiyoda, Nagoya, Aichi Prefecture
Title: Tossun Kobunshi E Nigyo Co., Ltd. 4, Agent 5, Detailed explanation of the invention column 6 of the specification subject to amendment, Line 11 of page 8 of the specification of the contents of the amendment amended as follows: do.

Claims (1)

[Scope of Claims] 1) A silicone rubber material that is plastic at room temperature and contains a vulcanizing agent is molded, and the molded product is immersed in high-temperature water heated to a temperature of 90 to 100°C. A method for producing a silicone rubber molded article, which comprises vulcanizing a silicone rubber material. 2) The method for producing a silicone rubber molded article according to claim 1, wherein the silicone rubber material is a low-temperature-curing silicone rubber base with a vulcanizing agent added in an amount of 1.3 times or more the standard amount.