JP2003123550A - Cable and resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cable prevented from discoloration of coating by an antioxidant in a sheath in regard to a cable used in a state applied with coating containing carboxylic acid metallic salt. SOLUTION: In the cable used in the state applied with the coating containing the carboxylic acid metallic salt, since 0.05 pts.wt. or more of the antioxidant other than that of a phenol group, for example, a polymer type antioxidant which is a hindered amine base antioxidant is added in 100 pts.wt. of base resin of a sheath material, even when there is an effect of a solvent or the like of a coating side, the hindered amine base antioxidant hardly migrates to the coating side, and even if it does migrate, it is not oxidized by the carboxylic acid metallic salt which is a hardener in the coating, and discoloration of the coating is effectively prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable and a resin composition for preventing discoloration of the paint due to a cable or resin composition used under application of a specific paint.

[0002]

2. Description of the Related Art In the case of a cable such as an electric cable or a communication cable, a sheath is usually coated on the cable core as a protective layer in order to protect the core portion from external damage. As the sheath material, polyolefins such as polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and ethylene-ethyl acetate copolymer (EEA) are mainly used from the viewpoint of its properties and cost. ing. A phenolic antioxidant is usually added to the base resin of the sheath material so that the sheath portion will not be thermally deteriorated by heat stress during extrusion or during use.

On the other hand, depending on the environment in which the cable having such a structure is used, a certain partition (room, etc.) including the cable may be coated with resin paint. For example, in the case of a ship or the like, an alkyd resin paint (varnish) may be applied to a room as an oxidative hardening type paint.

In this alkyd resin coating, a metal carboxylate (eg cobalt naphthenate, manganese naphthenate) or the like is used as a curing agent in order to accelerate the curing reaction at room temperature.

[0005]

However, a cable having an alkyd resin paint containing the curing agent and a sheath containing the phenolic antioxidant is
There was a problem that the paint would turn yellow when it came into contact.

The details of this discoloration are unclear, but it is presumed to be due to the following mechanism. First, the phenolic antioxidant in the sheath is extracted due to the influence of the solvent in the paint, and this antioxidant migrates into the paint. Next, it is considered that the migrated antioxidant is oxidized by the carboxylic acid metal salt as the curing agent contained in the paint, and the phenol group in the antioxidant is changed to a quinone structure which develops yellow or the like. .

From the mechanism of such discoloration, the present inventors first of all, as the antioxidant in the sheath, the substance which is difficult to migrate into the paint, and even if it migrates, is oxidized by the curing agent of the paint. I thought that discoloration could be prevented if the structure of the inhibitor changed and it was difficult to develop color.

The inventors of the present invention have made extensive studies from this viewpoint, and as antioxidants for the sheath, antioxidants other than phenol-based ones, such as hindered amine-based antioxidants of high molecular weight type, are used. In this case, it has been found that even if it comes into contact with an alkyd resin-based paint which is a paint containing a carboxylic acid metal salt (curing agent), it is difficult to discolor. Further, the addition amount is 0.0 with respect to 100 parts by weight of the base resin.
It has also been found to be good if it is 5 parts by weight or more. The present invention has been made from this point of view.

[0009]

The present invention according to claim 1 is a cable used under the application of a coating material containing a metal carboxylate, wherein 100 parts by weight of the base resin and an antioxidant other than phenol are used. A cable is characterized in that a sheath is made of a resin composition containing 0.05 parts by weight or more.

The present invention according to claim 2 is the cable according to claim 1, characterized in that the antioxidant is an antioxidant other than a high molecular weight phenol type.

The present invention according to claim 3 is a resin composition used under application of a coating material containing a carboxylic acid metal salt, wherein 100 parts by weight of a base resin and 0.05 parts by weight of a non-phenolic antioxidant are used. The resin composition is characterized by comprising at least one part.

The present invention according to claim 4 is the resin composition according to claim 3, wherein the antioxidant is a high molecular weight type antioxidant other than a phenol type antioxidant.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION As the base resin of the sheath material used in the present invention, various grades of polyethylene (HDPE, MDPE, LDPE, LLDPE, VLD) are used.
PE, etc.) and ethylene-based copolymers such as EVA and EEA. A thermoplastic elastomer such as styrene-butadiene-ethylene-styrene copolymer (SEBS) or the like may be added to the base resin for the purpose of improving heat resistance.

In order to impart flame retardancy to the above base resin, a metal hydroxide (magnesium hydroxide, aluminum hydroxide, etc.) or a flame retardant auxiliary agent is added, and if necessary, as a colorant, Carbon black and pigments can also be added.

The high molecular weight type antioxidant added to the base resin may be any antioxidant other than phenol type (including hindered phenol type), for example, hindered amine type antioxidant, Examples thereof include phosphorus-based antioxidants and lactone-based antioxidants. In particular, specific examples of the hindered amine-based antioxidant include
Dimethyl succinate and 4-hydroxy-2,2,6,6-
Polymer of tetramethyl-1-piperidine ethanol (molecular weight = about 3100 to 4000), dibutylamine-1,
3,5-triamine N, N'-bis (2,2,6,6
-Tetramethyl-4-piperidyl) -1,6-hexamethylenediamine.N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine (molecular weight = about 2600
~ 3400).

Since this antioxidant, for example, a hindered amine type antioxidant, is of a high molecular weight type, even if it is contacted with the alkyd resin type paint and is acted by the solvent in the paint, it migrates to the paint side. It is difficult and even if it is transferred, it is not oxidized by the metal salt of carboxylic acid, which is a curing agent in the paint, so that discoloration of the paint is effectively prevented.

Then, this addition amount is set to the base resin 100.
The amount of 0.05 parts by weight or more with respect to parts by weight means that 0.
This is because if the amount is less than 05 parts by weight, the amount is too small to obtain a desired antioxidant function, that is, sufficient heat aging characteristics. However, the upper limit is preferably about 3.0 parts by weight. The reason is that if the amount of addition is about 3.0 parts by weight, sufficient heat aging characteristics can be obtained, and if the amount is further increased, the cost will increase.

By covering the cable core with the thus-formed sheath material by extrusion or the like, the cable for electricity or communication which is the object of the present invention can be obtained. Then, after laying this cable in a room such as a ship, apply paint such as alkyd resin paint (varnish) containing carboxylic acid metal salt as a curing agent, or apply alkyd resin paint first. I laid this cable on the
Even if it comes into contact with the paint, the discoloration of the paint is effectively prevented because the above-mentioned high molecular weight hindered amine antioxidant is added to the base resin of the sheath material.

Further, not limited to the cable, in the case of the resin composition of the present invention, since the above-mentioned high molecular weight type hindered amine antioxidant is also added to the base resin, the curing agent The discoloration of the paint is effectively prevented even when the paint is used in contact with the paint side such as an alkyd resin system containing a metal carboxylate.

[Example] In the cable of the present invention, the effect of preventing discoloration of the sheath material and the function of preventing oxidation (heat aging characteristics)
In order to confirm that, sheets satisfying the conditions of the present invention consisting of various formulation examples shown in Tables 1 and 2 (Examples 1 to 7)
And sheets lacking the conditions of the present invention (Comparative Examples 1 to 7),
Each was manufactured as a sample. Then, each of these sheets was subjected to the following discoloration test and heat aging property test, and the discoloration of paint, heat aging property and its comprehensive judgment are also shown in the same table.

[Discoloration Test] Materials having the above-mentioned respective compositions were kneaded by a roll and then 170 ° C. × 10 10 by using a hot press.
Each sheet with a thickness of 3 mm is manufactured under the condition of minutes, and a white oxidative curing type alkyd resin coating is applied on each sheet for easy confirmation of discoloration, and it is left in the dark for 6 months. It was left to stand and the discolored state of the paint was observed with the naked eye. In determining discoloration, a glass plate coated with an alkyd resin paint was used for comparison, and a product that did not change much from white was passed (○). The test was rejected (x). In addition, the number of marks with large yellow discoloration was increased.

[Heat Aging Characteristic Test] After kneading the materials having the above-mentioned respective blends with a roll, a hot press is used to obtain 170 ° C.
Each sheet having a thickness of 1 mm was manufactured under the condition of × 10 minutes, and each sheet was further punched into a JIS No. 3 dumbbell piece shape to obtain a test sample piece. Then, first, the tensile strength and the elongation of these were determined. Next, each of the test sample pieces was placed in a hot air circulation type oven specified by JIS at 100 ° C. for 240 hours. afterwards,
The tensile strength and the residual rate of elongation were determined for each of the test sample pieces taken out from the oven. In determining the heat aging characteristics, when both the tensile strength and the residual rate of elongation after heating with respect to before heating are 80% or more, it is judged as pass (○), and when either one is less than 80%, it is rejected (×). ).

[0023]

[Table 1]

[0024]

[Table 2]

In each of the above Tables 1 and 2, the numerical value of the compounded material indicates the number of parts by weight. Note 1 in each table is EEA (E
A% = 9%, MI = 5), Note 2 is styrene-butadiene-ethylene-styrene copolymer (SEBS, MI = 2)
2), Note 3 phenolic antioxidant A is Irganox 1010 (trade name, manufactured by Ciba Specialty Chemicals), and Note 4 phenolic antioxidant B is Irganox 1076 (trade name, manufactured by Ciba Specialty Chemicals) The colorant in Note 5 is carbon black.

From the above Tables 1 and 2, it can be seen that the sheets (Examples 1 to 7) made of the compounded material according to the present invention are good in both the discoloration preventing effect and the heat aging property. . On the other hand, it can be seen that the sheets (Comparative Examples 1 to 7) made of the compounded material lacking the conditions of the present invention are defective in any of the discoloration preventing effect and the heat aging property.

[0027]

As is apparent from the above description, according to the cable of the present invention, a resin composition obtained by adding an antioxidant other than a phenol-based antioxidant, such as a hindered amine-based antioxidant, to a base resin is used. Because it is as a sheath,
The discoloration of the paint is effectively prevented even when the paint containing a metal salt of a carboxylic acid as a curing agent is used under the application of a paint such as an alkyd resin-based paint.

According to the resin composition of the present invention,
Since the base resin is a resin composition in which an antioxidant other than a phenol-based one, such as a hindered amine-based antioxidant, is added, a coating containing a metal carboxylate as a curing agent, for example, an alkyd resin-based coating Even when used under application, discoloration of the paint is effectively prevented.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4J002 AA001 BB031 BB061 BB071                       BC041 CM022 EU086 FD072                       FD076 FD090 FD130 FD202                       GQ01                 5G313 AA03 AB10 AC07 AD03 AE02

Claims (4)

[Claims] 1. A cable used under application of a coating material containing a carboxylic acid metal salt, the sheath comprising a resin composition comprising 100 parts by weight of a base resin and 0.05 parts by weight or more of a non-phenolic antioxidant. A cable characterized by: 2. The cable according to claim 1, wherein the antioxidant is a non-phenolic antioxidant in a high molecular weight form. 3. A resin composition used under application of a coating material containing a carboxylic acid metal salt, comprising 100 parts by weight of a base resin and 0.05 parts by weight or more of a non-phenolic antioxidant. And a resin composition. 4. The resin composition according to claim 3, wherein the antioxidant is a high molecular weight non-phenolic antioxidant.