JPH0570243B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an insulated wire, particularly an insulated wire coated with a polyvinyl chloride composition having excellent damage resistance. [Prior art] Insulated wires used for internal wiring in devices, etc. have excellent mechanical and electrical properties that can withstand long-term practical use, as well as toughness, damage resistance, and terminal resistance that can withstand harsh wiring or repair work. Various properties such as peelability of the insulator are required. Various insulating materials are used for these, but among them, polyvinyl chloride has a good balance of properties, is flame retardant, can be colored freely, is inexpensive, and has good processability. It is the most commonly used material because it has several characteristics that other materials do not have. Insulated wires for internal wiring in devices using polyvinyl chloride include vinyl-nylon class 2 insulated wires made of polyvinyl chloride coated with nylon, or semi-rigid vinyl wires coated with a semi-rigid polyvinyl chloride composition alone. is being put into practice. [Problems to be solved by the invention] Of these, the vinyl-nylon type 2 insulated wire has nylon applied to the outside, so it has excellent mechanical strength, especially abrasion resistance, and cut-through resistance. Because of this, manufacturing processes such as double extrusion are necessary, which naturally increases the price. In addition, there is a natural limit to the recent demand for thinner wires as equipment becomes smaller and lighter. On the other hand, although semi-rigid vinyl wire eliminates the drawbacks of these two types of insulated wire, it has inferior mechanical and thermal properties compared to nylon, so it is necessary to pull out one or several wires from a harnessed wire for wiring, etc. In many cases, the friction between the wires caused damage to the insulation, and in some cases, the conductor broke. The present invention has been made based on the above, and by providing a coating made of a polyvinyl chloride composition with extremely low frictional force, conductor breakage will not occur even when one or several wires are pulled out from a bundle. Of course, the present invention provides a novel insulated wire that can significantly reduce damage to the insulator and has excellent mechanical strength. [Means for Solving the Problems] The insulated wire of the present invention is produced by adding a plasticizer to 100 parts by weight of a partially crosslinked polyvinyl chloride resin having a tetrahydrofuran-insoluble gel content of 10 to 70% by weight and the remainder being a tetrahydrofuran-soluble content. It is characterized in that the conductor is coated with a resin composition containing 20 to 40 parts by weight and 0.5 to 5 parts by weight of silicone rubber. In the present invention, the partially crosslinked polyvinyl chloride resin having a gel content insoluble in tetrahydrofuran includes diallyl phthalate, diallyl maleate, triallyl cyanurate, triallyl trimellitate, trimethylolpropane trimethacrylate, and divinylbenzene in the vinyl chloride polymerization system. It is manufactured by a method in which a polyfunctional monomer such as the following is added and polymerized to produce an arbitrary amount of gel content. In the present invention, it is necessary to use a gel with a gel content of 10 to 70% by weight; if it is less than 10% by weight, the desired properties such as the surface friction coefficient cannot be obtained, and if it exceeds 70% by weight, it will be difficult to process. Sexual problems will arise. This processability is naturally related to the degree of polymerization of the remaining tetrahydrofuran soluble portion, but the degree of polymerization of the remaining portion is not particularly limited unless there is a problem with processability, but it is generally preferred that the average degree of polymerization is 3000 or less. In the present invention, a crosslinked polyvinyl chloride resin with a gel content of 100% is prepared and mixed with a general polyvinyl chloride resin soluble in tetrahydrofuran so that the gel content insoluble in tetrahydrofuran is in the range of 10 to 70% by weight. It is also possible to In addition, the tetrahydrofuran-insoluble gel content is 10 to 70.
Vinyl chloride and ethylene, within the weight% range.
It may be a copolymer with propylene, vinylidene chloride, vinyl acetate, etc., or a strong graft polymer with ethylene-vinyl acetate, chlorinated polyethylene, etc. Furthermore, polyvinyl chloride and ethylene-vinyl acetate, nitrile rubber, Blends with chlorinated polyethylene, acrylonitrile-butadiene-styrene, etc. are also included. Examples of plasticizers include phthalic acid esters such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, diisodecyl phthalate, and ditridecyl phthalate, fatty acid esters such as dioctyl adipate, dioctyl mazerate, and dioctyl sebacate, and tricresyl phosphate. ate, phosphoric acid esters such as trioctyl phosphate, epoxidized soybean oil, epoxidized substances such as epoxy resin, polyesters of adipic acid and sebastic acid, trioctyl trimellitate, tri-n-octyl trimellitate, etc. Examples include trimellitic acid ester, which can be used alone or in combination. The content of plasticizer must be between 20 and 40 parts by weight; if it exceeds 40 parts by weight, the mechanical properties will deteriorate and sufficient damage resistance cannot be achieved, and if it does not reach 20 parts by weight, extrusion processing will not be possible. Sexuality decreases. In the present invention, silicone rubber reduces frictional resistance without substantially impairing the excellent properties of polyvinyl chloride. This is because a thin film is formed on the surface of the polyvinyl chloride coating by exudation of silicone rubber, and since silicone rubber has low volatility, it can continue to maintain this performance for a long time. The reason why the amount of silicone rubber added is set at 0.5 to 5 parts by weight is that if it is less than 0.5 parts by weight, it has almost no effect in reducing frictional resistance, and if it exceeds 5 parts by weight, there is no compatibility, and it is extremely difficult to use polyvinyl chloride. This is to reduce the physical strength of the material. In the present invention, in addition to the above ingredients, various stabilizers such as lead salts and organotin stabilizers, various metal soaps such as stearic acid metal salts, various antioxidants such as phenolic antioxidants, halogens, phosphorus, etc. Various flame retardants such as compounds, flame retardant aids such as antimony trioxide and zinc borate, fillers such as clay, calcium carbon, and aluminum hydroxide, colorants, ultraviolet absorbers,
Various other compounding agents used in ordinary vinyl chloride compositions can also be added. [Example] Various properties of molded articles made from compositions based on the formulations shown in each example in Table 1 were measured.
The results are shown in the lower column of Table 1. The characteristics were measured as follows. (1) Static friction coefficient, dynamic friction coefficient: Press molded 1
Two sheets of mm x 30 mm x 100 mm are stacked together and a load of 1850 g is placed at 20℃ as shown in Figure 1.
The static and dynamic friction coefficients when moving at a speed of mm/min were determined from equations (1) and (2). In Fig. 1, 1 is a rail, 2 is a sliding block, 31 and 32 are sample sheets,
4 is a load, 5 is a motor, 6 is a load cell, and 7 is a recorder such as a chart. Static friction coefficient (μs) = static friction force (Fs) / load (w)...
…(1) Coefficient of kinetic friction (μk) = Dynamic friction force (Fk) / Load (w)……(2
) (2) Damage resistance: An insulated wire with an outer diameter of 1.1 mm coated with a tin plated annealed copper wire with a conductor diameter of 0.5 mm and a thickness of 0.3 mm was used. The test was conducted using a sample wire with a diameter of 20cm as shown in Figure 2.
A loop was made, one of the same sample wires was inserted into the loop, and a load of 1100 g was applied and the sliding operation was repeated to determine the number of times until the core conductor was exposed. In Fig. 2, 10 is a sample wire, and 11 is a ring.
is the sample electric wire passed through it, and 12 is the load. (3) Fusion property: The diameter of the electric wire made in the same manner as (2)
The wires were wound around a 20 mmφ metal rod so that they were in contact with each other, and after heating at 150°C for 1 hour, the fusion between the insulators was observed. Incidentally, those that were not fused were rated as ○, and those that were fused were rated as ×.

【table】

[Table] As is clear from Table 1, Examples 1 to 5 within the scope of the present invention are well-balanced in each characteristic. On the other hand, in Comparative Example 1, the content of silicone rubber was less than the specified value, and the damage resistance was poor. In Comparative Example 3, the content of gel insoluble in tetrahydrofuran was less than the specified value, and the fusion properties were poor. In Comparative Example 4, the content of gel insoluble in tetrahydrofuran exceeded the specified value, and the processability was poor, making it impossible to prepare a sample. In Comparative Example 5, the content of plasticizer was higher than the specified value, and the damage resistance was poor. [Effects of the Invention] As is clear from the above invention, the present invention achieves the advantages of polyvinyl chloride compositions that are inexpensive, have good processability, are flame retardant, can be freely colored, and do not impair their various properties. A new well-balanced insulated wire that can eliminate accidents such as damage to the insulation and disconnection of the conductor can be obtained.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams showing methods for measuring frictional resistance and testing damage resistance for samples of the present invention. 31, 32...sample sheet, 10...sample wire loop, 11...sample wire.

Claims (1)

[Claims] 1 Tetrahydrofuran insoluble gel content 10-70% by weight
Add a plasticizer to 100 parts by weight of partially crosslinked polyvinyl chloride resin, the remainder of which is tetrahydrofuran soluble content.
1. An insulated wire comprising a conductor coated with a resin composition containing 20 to 40 parts by weight and 0.5 to 5 parts by weight of silicone rubber.