JPS5839436A - Rubber plug - Google Patents

Abstract

PURPOSE:To obtain a rubber plug contg. only small amt. of soluble substance and having excellent oil resistance and is suitable as a plug for a vessel for containing injection medicines, chemicals, etc., by crosslinking a mixture of a nitrile rubber and a halogenated butyl rubber using an organic peroxide. CONSTITUTION:As a crosslinking agent an organic peroxide (e.g. ''Perhexa- 2.5B '' manufactured by Nippon Yushi Co.) is added to the mixture containing 70-90wt% nitrile rubber and 30-10wt% halogenated butyl rubber, and the mixture is molded and crosslinked to obtain a rubber plug.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oil-resistant composition with a small dissolution rate, which is used in injection drugs, reagents, and pharmaceutical crystals.

Conventionally, the compositions used in the above chemicals have oil as the main component or dispersant, and nitrile comb (hereinafter referred to as NBI) is the main component, and sulfur and vulcanization accelerators are generally used as crosslinking agents. However, as the oil sews, the crosslinking agent elutes over time, reducing the purity of the drug and making it unsafe.Furthermore, high-quality drugs with few foreign substances are required, and as a result, containers are As it has become a requirement that no foreign matter be generated, it is natural that materials with even fewer eluable materials than conventional ones are required.

The generation of eluates from combustible materials is mainly due to sulfur and vulcanization accelerators, but if the cause of the increase in eluables is due to the additives in reinforcing agents, this can be reduced. In the case of sulfur and vulcanization accelerators, if they are reduced, vulcanization will not occur and the physical properties will also decrease, making it easier to mix and elute the mixture. Although the elution of the compounding ingredients disappears, excess sulfur and vulcanization accelerator are eluted, and the hardness is too high, resulting in poor needle stickiness, which is a characteristic of combs.

In other words, determining the suitability of the crosslinking agent is a factor that determines the superiority or inferiority of the composition.

Usually, sulfur and organic accelerators are added to 3 to 6 tumor areas for each mass component ioo * pars compacta. As an example, the formulation and performance of conventional comzen are shown in Table 1.

Table 1 (Formulation) Part by weight NBR (JARN 2308 Nippon Gosei Jmu■com
1 o.

Silica (made by Nlpsil VN-3 Memoto Silica ■) 20
Process oil (Comolex No. 2 manufactured by Nippon Oil Co., Ltd.)
5 Pigments (Carposis 5-) manufactured by Showa Denko)
0.2 zinc oxide (zinc oxide No. 1 manufactured by Sakai Chemical Co., Ltd.)
3 Sulfur (fine sulfur manufactured by Hosoi Chemical)
2 Vulcanization accelerator (Tsukusera DN Ouchi Shinko Chemical)
) 1.5 vulcanization accelerator (Noxe 5-TT Ouchi Shinko Chemical)
(manufactured by) 0.5 total 132.2 parts by weight (physical properties) Hardness 50% hydrium acid reducing substance 8.5
-Visible transmittance 430μ
93.0% olein ethyl immersion hardness change
6. On the other hand, when a modified peroxide is used as a crosslinking agent, the amount used is small and the effect can be sufficiently exerted with less than double placement, so that the eluate is also reduced. An example is shown in Table 2.

Table 2 (composition) Part by weight NBR (same as Table 1)
to.

Silica (same as in Table 1) 20% Sesoil (same as in Table 1)
5 organic overgrowth compound (bar medium+j2.5B Nippon Oil & Fats ■
(manufactured by) 1 total 126 parts by weight (physical properties) Hardness 53%:
J Potassium Ganate Reducing Substance 6
．． 5-Visible transmittance
99.2%, that is, cross-linking with organic peroxide has less eluate than cross-linking with sulfur.If the composition shown in Table 2 is used to produce combs, the hardness will be low and comb pieces will be generated when punctured. Generally, modified peroxides as crosslinking agents have lower tear resistance than sulfur and are unfavorable for the needle stickiness of the composition.The present inventors should improve this point (, NB
We focused on precipitating halogenated butylcomb to R. The crosslinking efficiency of NBH is 1.
0, and 0.5 is 0.5. That is, it is more difficult to crosslink than NBRFi halogenated butylcomb, and therefore exhibits a smaller hardness value. In other words, we found that the hardness changes by changing the ratio of NBR and butyl comb.We thought that if we applied this to a comb base, we could obtain a material with a little less eluate, so we investigated the precipitate ratio. and obtained the following results. In other words, it was found that when using Precitocom, which was composed of 70 to 90 weight percent NBR and 10 to 300 to 30 parts by weight, the crosslinked product had less eluate and was superior in shopping properties. .

When the butyl comb is placed under 10 parts by weight, no decrease in hardness is observed, and above 300 parts by weight, the hardness decreases significantly and the physical properties deteriorate. At this time, even if the amount of organic peroxide is increased, almost no effect is observed, and on the contrary, the amount of eluate increases.

Furthermore, if the amount of nitrile in NBFt is less than 25 times, the oil resistance of the product will decrease and it will not be compatible with commercially available oil-based pharmaceuticals.

Examples Table 3 shows the formulations shown in Table 3, which were cross-linked with organic peroxide, and the physical properties of the products were measured, which are shown in Table 3.
80 65 Silica (same as Table 1) 10
10 10 10 Hardness 5
2 44 45 32 Potassium permasiganate (g) 6.5 6.5 6.3
9.0 visible part transmittance 430p%%) 99
．． 0 99.8 99.8 90 Olay” ethyl immersion (
Hardness)"'4"6'10
Needle stickability: Good ” Excellent Good A1
In the comparative example, there was little eluate, but the gorge was hard and
Worst needle stickiness. In addition, in the comparative example of A4, there were many eluted substances,
The branching is low, and the needle stickability is inferior to that of the present invention. Inventions A2 and 3 have little eluate, appropriate hardness, and excellent needle stickability.

As mentioned above, rubber foam made by mixing NBR with halogenated comb and cross-linking the 716-component mixture with organic peroxide has few eluates and has excellent physical properties of needle stickiness and contact with oil. Useful as rubber for injection drugs, reagents, and chemicals〇193-

Claims (1)

[Claims] A composition characterized in that a rubber component is a mixture of 0 to 90 % of Nitsil 16F and 1 % of butyl halogenide 1O to 301iJ, which is crosslinked with an organic peroxide.