Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Cellular products or processes of preparing a cellular...
Patent
1995-08-11
1997-09-23
Foelak, Morton
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Cellular products or processes of preparing a cellular...
521 94, 521142, 521143, 521145, C08J 910
Patent
active
056705514
DESCRIPTION:
BRIEF SUMMARY
TECHNOLOGICAL FIELD
This invention relates to a crosslinked foamed body and a process for its production. More specifically, it relates to a crosslinked foamed body best suited for use as a wet suit which can be colored in a brilliant color and has excellent weatherability, pliability and shape retention, and to a process for its production.
BACKGROUND TECHNOLOGY
A crosslinked foamed body of chloroprene rubber has been conventionally used as a material for wet suits. Since the crosslinked foamed body of chloroprene rubber is soft and has excellent shape retention, it is suitable as a material for wet suits. However, in recent years, needs for fashionability of wet suits have increased, there has been a strong need for bright colors instead of a conventional black color. When products having bright colors are produced from the crosslinked foamed body of chloroprene rubber, there is a problem in that a crush occurs under sunlight because of the lack of weatherability.
On the other hand, a crosslinked foamed body of chlorosulfonated polyethylene is known as a crosslinked foamed body having excellent weatherability. But since this crosslinked foamed body is like a resin and lacks suppleness, it has inferior shape retention and cannot be used in uses which require suppleness and shape retention.
Japanese Laid-Open Patent Publication No. 266151/1989 describes a foamed body prepared by vulcanizing and foaming an ethylene chloride and .alpha.-olefin copolymer rubber. This foamed body has a good skin and holds suppleness and strength even after the lapse of time and does not show a large swelling even when it makes contact with a machine oil. But these characteristics are not entirely sufficient in utilities of wet suits which require both fashionability and functionality. Sometimes, the foaming is not uniform, the foamed body contracts after vulcanization and foaming, poor appearances such as fine creases may form on the surface, and foaming does not take place sufficiently.
DISCLOSURE OF THE INVENTION
An object of this invention is to provide a crosslinked foamed body which can be colored brilliantly and has excellent weatherability, suppleness and shape retention and good outer appearance, and a method of its production.
The present invention provides such crosslinked foamed body and a method of its production as follows:
(1) A crosslinking and foaming composition comprising (A) a chlorinated ethylene/.alpha.-olefin copolymer rubber having a chlorine content of 20 10 to 190, (B) a triazine thiol represented by the following formula (1) ##STR1## wherein R.sup.1 is --NR.sup.2 R.sup.3, --OR.sup.2, or --SR.sup.2, in which each of R.sup.2 and R.sup.3 represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group, (C) an alkyl ammonium halide, and (D) a hydrazide-type blowing agent, said crosslinking and foaming body being vulcanized and foamed in two stages at an expansion ratio of 3 to 10 times at a first step vulcanization temperature of 120.degree. to 140.degree. C. for a vulcanization time of 5 to 10 minutes and at a second step vulcanization temperature of 125.degree. to 160.degree. C. which is higher than the first step vulcanization temperature by at least 5.degree. C. for a vulcanization time of 5 to 20 minutes.
(2) A method of producing a crosslinked foamed body which comprises vulcanizing and blowing a crosslinking and foaming composition at a first step vulcanization temperature of 120.degree. to 140.degree. C. for a vulcanization time of 5 to 10 minutes and a second step vulcanization temperature of 125.degree. to 160.degree. C. which is higher than the first step vulcanization temperature by at least 5.degree. C. for a vulcanization time of 5 to 20 minutes in two stages so that the expansion factor becomes 3 to 10 times, said crosslinking and foaming composition comprising (A) a chlorinated ethylene/.alpha.-olefin copoymer having a chlorine content of 20 to 40% by weight and a Mooney viscosity of blowing agent.
PREFERRED EMBODIMENTS OF THE
REFERENCES:
patent: 5004787 (1991-04-01), Tojo et al.
patent: 5310818 (1994-05-01), Tojo et al.
patent: 5470919 (1995-11-01), Tojo et al.
Matsumoto Muneyuki
Matsuo Yoshihisa
Okada Keiji
Uchimi Akemi
Foelak Morton
Mitsui Petrochemical Industries Ltd.
LandOfFree
Crosslinked foamed body and a process for its production does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Crosslinked foamed body and a process for its production, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Crosslinked foamed body and a process for its production will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1938859