JPS60190440A - Filler for rubber or resin - Google Patents

Abstract

PURPOSE:To obtain a filler composed of calcium carbonate, calcium oxide, and alumina potassium silicate clay each having fine particle size, and capable of giving a molded article having low void content without lowering the original strength when compounded to a rubber or resin and kneading and molding the compound. CONSTITUTION:The objective filler is produced by mixing (A) 20-90pts.(wt.) of calcium oxide having an average particle diameter of <=1mum (prepared by finely pulverizing calcined calcium carbonate), (B) 10-50pts. of calcium carbonate (preferably having an average particle diameter of <=0.02mum and prepared by passing carbon dioxide gas to the above calcium oxide) and (C) 10-30pts. of alumina potassium silicate clay (preferably having an average particle diameter of <=1mum and prepared by finely pulverizing celicite, etc.). A molded article having low void content, free from blooming, and having the original strength can be produced by kneading the filler in a rubber or resin, and molding the compound.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a filler, and more particularly to a filler for rubber and resin. Air bubbles form in the body, reducing the properties characterized by strength of the molded body. The dust generated during the smelting of extremely fine calcium legate, iron silicon, or silicon metal has been added and kneaded during the molding of rubber or resin.

However, even when such a strong filler is used, many air bubbles are observed in the molded product obtained, and the strength is accordingly reduced.

In addition, the surface of the molded article had a drawback that a bloom phenomenon was likely to occur.

The present inventor conducted research on rubber or resin fillers that do not have such drawbacks, and as a result, a mixed composition of calcium carbonate, calcium oxide, and potassium alumina silicate clay having fine particle sizes was found to be the filler. This led to the completion of the present invention based on the knowledge that this method imparts excellent properties to rubber molded articles or resin molded articles.

That is, the gist of the present invention is a filler whose main component is a mixed composition of calcium carbonate, calcium oxide, and potassium alumina silicate clay having a fine particle size.

Calcium carbonate having a fine particle size can be obtained by pulverizing calcium carbonate (limestone) and sieving it in a conventional manner. Furthermore, if carbon dioxide gas is passed through calcium oxide obtained by calcining lime carbonate, the average particle size will be 0.0
One with a diameter of 2 μm or less can be obtained. When this material is used, the rubber or resin molded product will not have bubbles and will have even better properties.

If the particle size of calcium carbonate is 1 μm or more, the filler will not be wetted by 11I & or rubber, which is not preferable.

Calcium oxide can be obtained by calcining lime carbonate in a conventional manner and pulverizing the resulting calcium oxide.

alumina potassium silicate clay) (ga)
, ox, o.3Al, 0.・6H, O) is exemplified, and it is preferable that it is finely pulverized to have an average particle size of 1 μm or less when used.

The composition of the filler of the present invention is preferably 20 to 90 parts by weight of the 0°0 component, 10 to 50 parts by weight of calcium carbonate, and 10 to 30 parts by weight of potassium alumina silicate clay.

In order to produce a molded article of rubber or #'i resistance using the filler of the present invention, stearic acid is added to the rubber or resin base material.
It is obtained by adding additives such as zinc white, sulfur, and carbon and the filler of the present invention and kneading and molding.

If rubber or resin is kneaded and molded using the filler of the present invention, the resulting molded product will have a small bubble content and will not have a decrease in strength.

Further, no bloom phenomenon is observed even if left for a long time.

Although it is theoretically unclear how this blooming phenomenon is prevented, the crystal shapes of the fractured surfaces of calcium oxide, calcium carbonate, and potassium aluminosilicate clay are different, and when mixed, they intersect without any gaps, forming rubber and 1illllW molding. It is thought that it fills up the body and prevents substances that cause the bloom phenomenon from migrating from the inside of the rubber or resin molded product to the surface.

Next, the present invention will be explained with reference to Examples, but the present invention is not limited thereto.

Example 1 Calcium carbonate obtained by pulverizing common quicklime to an average particle size of 1 μm, 50 parts by weight, calcining calcium carbonate to obtain calcium oxide, and carbonating the obtained calcium oxide. The average particle diameter is 0.02 μm]
A composition obtained by mixing 0 parts by weight and 20 parts by weight of sericite clay (finely pulverized to an average size of 1 μm) was used as a filler (6) for a rubber material.

These fillers were mixed in the proportions shown below, and each of the resulting mixed compositions was mixed with 10 x 10 x 1 OcIn.
It was placed in a metal box and heated and molded at 120°C under normal pressure.

The expansion coefficient, apparent specific gravity, and
Table 2 shows the results of determining the true specific gravity. The expansion rate is fC according to the formula below.

Further, each of Examples 1 to 3, Comparative Examples 1 to 3, and the blank product was vulcanized at 150°C for the time shown in Table 3, and the resulting vulcanized products had 300% tensile stress, elongation, tensile strength, and hardness. Table 3 shows the results obtained using JIBK6301.

Table 2 Expansion rate C%) Blank 0 27.2 0.889 1.131 Comparative example 1 5 8.8 1.0?9 1.154 Comparative example 2
10 4.4 1.124 1.1'73 Comparative Example 3 1
5 B, 4 1.150 1.189 Example 1 5 7
．． 8 1.078 1.153 Example 2 10 B, 7
1.141 1.183 Meiji Example 3 15 2.3 1
．． 167 1.194 True specific gravity Apparent specific gravity of nibbles rubber plate; Oven rubber plate No. 3 Table Vulcanized rubber - Film physical property test (press vulcanization) Based on JIB K 6301 Furthermore, blank, Comparative Examples 1 to 3 and Examples 1 to 3
Each of the compositions 1 was vulcanized in an oven at 150°C for 60 minutes (normal pressure), and each of the obtained vulcanized products was subjected to a hot air vulcanization shrinkage test, and the results are shown in Table 4. .

Further, a vulcanization degree test was conducted on each of the samples, and the results are shown in Table 5.

Table 4 Hot air vulcanization shrinkage test Oven vulcanization at 150°C for 60 minutes (normal pressure) Shrinkage rate (%) Parallel grain Perpendicular direction As is clear from Table 2, the example products are the comparative example products with the same filler added. It was found that the expansion rate was smaller when compared to the comparison example product.The true specific gravity of the example product was also larger than that of the comparative example product, indicating that the example product contained more air bubbles than the comparative example product. This was consistent with the results of visual observation.

Also, from Table 3, the example products have the same filler, and
When compared with the comparative example products with the same vulcanization time, it was found that the 300% tensile stress, elongation, and tensile strength were greater in all cases.

Furthermore, as is clear from Table 4, it was found that the change in the shrinkage rate of the product was smaller δ in the Example product than in the Comparative Example product even when the amount of filler added was increased.

Also, leave one of each product in the blade chamber,
Plume phenomena were observed for each product. As a result of observation, a bloom phenomenon was observed in the comparative example product and the blank product, but almost no bloom phenomenon was observed in the example product.

Examples 4 to 6 Calcium carbonate used in Example 1 (average particle size 0.0
A filler was prepared according to Example 1, except that particles with an average particle size of 1 μm were used instead of 2 μm.
) Example 4 5 8. Ol, 075 1.153 Example 5
to 4.0 1.133 1.184 Example 6 1
5 2.9 1.159 1.193 Table 6 Vulcanized rubber - Membrane physical property test (press vulcanization) Based on JI8 K 6301 Table 7 Hot air vulcanization shrinkage test Open vulcanization 150°C x 60 minutes (normal FE) Shrinkage factor(%)
Parallel grain, perpendicular direction This filler, the base material and additive B used in Example 1 were mixed and molded according to Example 1, and the physical properties of the obtained molded body were evaluated according to Example 1. I measured it. Further, the molded body was vulcanized according to Example 1, and various properties of the obtained product were measured. The results obtained are shown in Table 5-7.

From these results, it can be seen that Example products 4 to 6 have different filler types, but Comparative Example products 1 to 6 have the same content.
3, the example product was superior to the corresponding comparative example product, but was seen to be slightly lower than the example products 1 to 3.

Patent applicant: Sankeikaru Co., Ltd. Representative Patent Attorney Tsukasa Manno

Claims (1)

[Scope of Claims] (1) Calcium oxide having an average particle diameter of 1 μm or less;
Rubber or W fat filler containing calcium carbonate and potassium alumina silicate clay (2. In claim 1, calcium carbonate is made by calcining carbonated lime to form calcium oxide, Next, carbon dioxide gas is passed through this to make calcium carbonate, and the average particle size is reduced to 0.
．． Rubber or Ti1 fat filler having a particle size of 0.02 μm or less
0 to 50 parts by weight and 10 to 30 parts by weight of alumina-silicate clay
(4) Rubber or resin filler characterized in that the amount is parts by weight (4) A filler for rubber or resin according to any one of claims 1 to 3, in which the potassium alumina silicate clay is sericite.