Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Reexamination Certificate
2000-07-07
2002-12-31
Szekely, Peter (Department: 1714)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
C174S1100SR, C174S1100PM, C524S436000, C524S437000
Reexamination Certificate
active
06500882
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a flame-retardant, a flame-retardant resin composition and its use, particularly its use as a cable. More specifically, it relates to a flame-retardant which is obtained by surface-treating a metal hydroxide with an emulsion of a copolymer or polymer and can provide a flame-retardant resin composition excellent in processability and acid resistance, a flame-retardant resin composition containing said flame-retardant, a molded article of said flame-retardant resin composition and use of said molded article, particularly use as a flame-retardant cable.
PRIOR ART OF THE INVENTION
A halogen-containing flame-retardant which is obtained from an organic halogen compound, antimony trioxide or a combination of an organic halogen compound and antimony trioxide, has caused a problem socially, since it generates a great deal of smoke and poisonous gases in fire. Therefore, there have been vigorously made development works for a flame-retardant with the smallest amount of the halogen-containing flame-retardant. Consequently, there have been obtained estimation that an inorganic compound, particularly a metal hydroxide typified by magnesium hydroxide or aluminum hydroxide, is an effective flame-retardant. A resin composition containing a metal hydroxide causes little smoke in fire and it is nonpoisonous. Further, when aluminum hydroxide is used, there is found a phenomenon that part of the aluminum hydroxide itself is dehydrated and decomposed at a processing temperature of a resin to cause bubbles in a resin molded article. However, magnesium hydroxide is free from such a phenomenon so that many resins are suitable for use.
A synthetic resin containing a flame-retardant composed of magnesium hydroxide or aluminum hydroxide in a high concentration is broadly used for electric wires in nuclear plants, ships, vehicles, subways and communications lines, parts of home electric appliances and electronic devices, construction materials and so on.
However, when a product containing magnesium hydroxide is subjected to an acid rain or a highly humid condition a for a long time, the problem is that the magnesium hydroxide reacted with carbonic acid, etc., is precipitated in the form of magnesium carbonate or basic magnesium carbonate to whiten a surface and impair the appearance of a molded article. Further, the magnesium hydroxide in a resin gradually moves to the surface of a product, which decreases inherent flame retardancy. Products containing magnesium hydroxide which is a polarity material in a large amount are poor in water-resistance. When these products are subjected to water for a long period of time, the volume resistivity thereof which shows electric properties is decreased. Therefore, the kind of a usable electric wire is limited. When attempts to give sufficient flame-retardancy to a resin with a metal hydroxide are carried out, it is required to incorporate the metal hydroxide into the resin in a high concentration. Consequently, the problem is that processability (productivity) becomes poor. That is, when the metal hydroxide is incorporated into the resin, the problem is that the processability, water-resistance and acid resistance of a resin composition and a molded article thereof deteriorate. There are proposed flame-retardants surface-treated with higher fatty acids, alkaline metal salts thereof, or various coupling agents such as a silane-containing coupling agent and a titanium-containing coupling agent. The water-resistance and acid-resistance are improved to some extent depending upon the kind of a surface-treating agent. However, the flow of a resin composition in an extruder is impaired. That is, the processability becomes poor. Further, depending upon the kind of a surface-treating agent, processability is improved but water-resistance and acid-resistance are decreased. On this account, the use of the surface-treating agent has not overcome the above problems.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a flame-retardant which overcomes the above problems and can give a flame-retardant resin composition excellent in acid resistance, water resistance and processability, a flame-retardant synthetic resin composition containing said flame-retardant and a molded article of said resin composition.
According to the present invention, there is provided a flame-retardant for a synthetic resin, which is obtained by surface-treating a magnesium hydroxide with an emulsion of a copolymer or polymer of the formula (1),
wherein X is any one of hydrogen, a phenyl group and an alkyl phenyl group, Y is hydrogen, an alkyl group or an organic group having a functional group, each of R
1
and R
2
is hydrogen or an alkyl group, m is 0 or a positive integer, n is a positive integer, and “~” shows that each monomer is copolymerized at random in a main chain, the formula (2),
wherein X is any one of hydrogen, a phenyl group and an alkyl phenyl group, Y is hydrogen, an alkyl group or an organic group having a functional group, each of R
1
and R
2
is hydrogen or an alkyl group, m is 0 or a positive integer, n is a positive integer, and “~” shows that each monomer is copolymerized at random in a main chain, or the formula (3),
wherein X is any one of hydrogen, a phenyl group and an alkyl phenyl group, each of Y
1
and Y
2
is hydrogen, an alkyl group or an organic group having a functional group, each of R
1
, R
2
and R
3
is hydrogen or an alkyl group, each of a, b and c is a positive integer, and “~” shows that each monomer is copolymerized at random in a main chain.
The present invention relates to a flame-retardant, a flame-retardant resin composition and its use, particularly its use as a cable. More specifically, it relates to a flame-retardant which is obtained by surface-treating a magnesium hydroxide with an emulsion of a copolymer or polymer and can provide a flame-retardant resin composition excellent in processability and acid resistance, a flame-retardant resin composition containing said flame-retardant, a molded article of said flame-retardant resin composition and use of said molded article, particularly use as a flame-retardant cable.
According to the present invention, there is further provided a molded article obtained from the above flame-retardant resin composition.
According to the present invention, there is further provided a flame-retardant cable in which an electrical conductor is covered with an insulation layer directly or through another layer or in which the circumference of the above insulation layer is covered with a sheath layer through further another layer or through no layer, wherein at least one layer of the insulation layer or the sheath layer is composed of the above molded article.
The flame-retardant of the present invention is obtained by surface-treating a magnesium hydroxide with an emulsion of a copolymer or a polymer of the formula (1),
wherein X is any one of hydrogen, a phenyl group, and an alkyl phenyl group, Y is hydrogen, an alkyl group or an organic group having a functional group such as a vinyl group or an epoxy group, each of R, and R, is hydrogen or an alkyl group, m is 0 or a positive integer, n is a positive integer, and “~” shows that each monomer is copolymerized at random in a main chain, the formula (2),
wherein X, Y, R
1
, R
2
, m, n, and “~” are as defined in the formula (1),
or the formula (3),
wherein X, R
1
, R
2
, and “~” are as defined in the formula (1), each of Y
1
and Y
2
is hydrogen, an alkyl group or an organic group having a functional group such as a vinyl group or an epoxy group, R
3
is hydrogen or an alkyl group, and each of a, b and c is a positive integer.
DETAILED DESCRIPTION OF THE INVENTION
The copolymer or polymer used in the present invention is those copolymers and polymers of the formulae (1) to (3). Examples of the copolymers and polymers of the formula (1) or the formula (2) include polymers or copolymers of acrylic acid ester, ethylene.acrylic acid ester, styrene.acrylic acid ester, methacrylic acid ester, eth
Hiraishi Wataru
Sawa Yoshiharu
Tachifuji Tomoko
Yoshii Makoto
Kyowa Chemical Industry Co. Ltd.
Szekely Peter
LandOfFree
Flame-retardant, flame-retardant resin composition and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Flame-retardant, flame-retardant resin composition and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flame-retardant, flame-retardant resin composition and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2942846