JP2942308B2 - Polyester fiber with high friction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a polyester fiber having a high frictional property suitable for preventing slippage of a sock sole, the inside of a glove, a hanger or the like.

<Prior Art> Polyester is widely used as a raw material for producing fibers, films and the like because of its excellent mechanical, electrical and thermal properties.

However, studies on the composition and shape of polyester fibers that give high friction have been shallow, and polyester fibers having a sufficiently high coefficient of friction have not been developed.

<Problems to be Solved by the Invention> An object of the present invention is to obtain a polyester fiber having a high frictional property suitable for preventing slippage of, for example, the bottom of socks, the inside of gloves, a hanger, etc., which cannot be obtained with conventional synthetic fibers. It is to provide.

<Means for Solving the Problems> That is, according to the present invention, the melt index (MI) is 20 or more.
10-60% by weight of polyester elastomer which is 50 or less
It is a polyester fiber characterized by having a metal dynamic friction coefficient of 0.7 or more, preferably a polyester elastomer, from a hard segment mainly composed of butylene terephthalate units and a soft segment mainly composed of polybutylene glycol units. Polyester fiber.

The polyester elastomer used in the present invention is not particularly limited as long as the melt index (MI) is from 20 to 50. Basically, a hard segment mainly composed of an alkylene terephthalate unit, an aliphatic polyether and And / or a block copolymer comprising a soft segment comprising an aliphatic polyester.

Examples of the polyester mainly comprising an alkylene terephthalate unit as a hard segment include those mainly composed of terephthalic acid and an alkylene glycol such as ethylene glycol, propylene glycol, butylene glycol, and hexamethylene glycol. And butylene glycol are preferred.

Examples of the aliphatic polyether and / or aliphatic polyester as the soft segment include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polybutylene glycol, mixtures and copolymers thereof, and polyethylene adipate and polyethylene. It may be an aliphatic polyester such as sebacate or polybutylene adipate, or a copolymer of the above aliphatic polyether and aliphatic polyester. As the soft segment, polybutylene glycol is preferable, the molecular weight is 400 to 4000, and it is desirable that the soft segment is present in the polyester elastomer at a ratio of 10 to 60% by weight.

Such a polyester elastomer can be obtained by a conventionally known polycondensation method.For example, terephthalic acid or its dimethyl ester, butylene glycol and polybutylene glycol can be obtained in the presence of a catalyst in the range of about 150 to 250.
A polyetherester block copolymer by heating to ℃ and performing an esterification or transesterification reaction, and then performing polycondensation while removing excess glycol under vacuum, or a hard segment prepared in advance. There is a method obtained by reacting a prepolymer and a soft segment prepolymer with an organic diisocyanate compound which reacts with a terminal functional group of the prepolymer.

The melt index (MI) of the polyester elastomer is from 20 to 50 as described above, and preferably 30 ≦
MI ≦ 40 is better. If the melt index is less than 20, the rigidity of the polyester fiber containing the elastomer is lost, and the spinnability during spinning is poor, and there is a problem in operability.

When the melt index is larger than 50, there is a problem in terms of high friction properties, and the spinning condition tends to be poor in spinnability.

The content of the polyester elastomer with respect to the fiber is
It should be 10-60% by weight, preferably 20-50% by weight, more preferably 30-45% by weight. If it is less than 10% by weight, a metal having a coefficient of dynamic friction resistance of 0.7 or more cannot be obtained, and if it exceeds 60% by weight, it is difficult to form a fiber.

In the present invention, as the polyester to be mixed with the polyester elastomer, for example, polyethylene terephthalate composed of ordinary terephthalic acid and ethylene glycol can be mentioned, but other copolymer components, for example, sulfoisophthalate as a representative acid for modification. Sodium acid, isophthalic acid, adipic acid, sebacic acid, etc.
It may be a copolymerized polyester used in an amount of at most mol%.
Further, a small amount of other polyester may be mixed.

Next, the coefficient of metal kinetic friction of the polyester fiber of the present invention containing a polyester elastomer must be 0.7 or more, preferably 0.9 or more. (However, when measuring the friction coefficient, it is assumed that no oil agent adheres to the fiber surface.) If the metal dynamic friction coefficient is smaller than 0.7, sufficient stopper effect cannot be obtained and processed into products requiring high friction In such a case, the performance cannot be exhibited.

The spinning method of the polyester fiber of the present invention is not particularly limited, and, for example, a normal polyester chip and a polyester elastomer are blended and extruded using a melt extruder,
The fibers can be formed into fibers through a die having an arbitrary shape.

<Examples> Next, the present invention will be described with reference to specific examples, but the present invention is not limited thereto.

In addition, the measured value in an Example is measured by the following method.

Measurement of metal dynamic friction coefficient: The measurement was performed in the following manner according to JIS L1015-19817.13.

The sample is thoroughly defibrated with a hand card to form an even sliver. A sample fiber with an initial load (100mg) attached to one end is applied to the center of a chrome-puffed cylinder with an outer diameter of 8mm of a radar-type friction coefficient tester. Connect the end to the hook of the torsion balance. To measure the dynamic friction coefficient (μd), the cylinder is rotated at a circular velocity of 1800 cm / min, the load at which both ends of the fiber are balanced is determined by torsion balance, and the friction coefficient is calculated by the following equation.

 The number of tests is 30 times in total, and the average value is shown.

W: Load applied to fiber (mgf) {N} m: Torsion balance reading (mgf) {N} Measurement of melt index (MI): According to ASTM D-1238.

That is, the MI value is defined as the weight at which a melt at 230 ° C. is extruded through a specific orifice in 10 minutes when a load of 2160 g is applied on the piston.

Examples 1-4, Comparative Example 1 Polyethylene terephthalate having an intrinsic viscosity [η] of 0.65 was blended with polyester elastomers having different melt indices in various ratios as shown in Table 1, and spinning and drawing was carried out by a usual method. A polyester fiber having a fineness of 2 denier was obtained.

In Comparative Example 1, sufficient high friction performance could not be obtained because the elastomer content was 5%.

Reference Example 1 The polyethylene terephthalate used in Example 1 alone was spun without blending a polyester elastomer.
It is stretched to obtain a fiber having a denier of 2 fibers and a denier of 2 deniers. A fiber having no oil agent and lauryl phosphate Ka salt / PEG (10
00) The metal kinetic friction coefficient was measured for a dilaurate (60/40) oil solution to which 0.15% by weight was adhered. As a result, it was found that the friction property was 0.287 in the case where the oil agent was attached and 0.375 in the case where the oil agent was not attached, which was much lower than the fiber of the present invention.

<Effects of the Invention> According to the present invention, a polyester fiber having extremely excellent high frictional properties can be obtained, which is suitable as a material for socks, work gloves, slippers on hangers, and the like.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-90877 (JP, A) JP-A-63-227813 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D01F 6/92 D01F 6/86 D01F 6/62 302

Claims (2)

(57) [Claims] 1. A polyester characterized in that an ethylene terephthalate-based polyester contains 30 to 60% by weight of a polyester elastomer having a melt index (MI) of 20 or more and 50 or less and a metal dynamic friction coefficient of 0.7 or more. fiber. 2. The polyester fiber according to claim 1, wherein the polyester elastomer comprises a hard segment mainly composed of butylene terephthalate units and a soft segment mainly composed of polybutylene glycol units.