JPS6018401B2 - footwear - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to footwear having superior non-slip properties.

Traditionally, footwear has been divided into high-quality handmade types and inexpensive injection molded types.

Injection molded types are often used for children's shoes, sandals, etc.
The bottom is made of soft polyvinyl chloride (P) to reduce costs.
VC) resins have been used. However, just PVC
When chisels were used, they were slippery and easily abraded, and the soles of the shoes became hard in the winter. Therefore, footwear with soles made of PVC with inorganic granules dispersed therein was manufactured, but the machine was subject to severe wear and tear, which was undesirable. In order to overcome these drawbacks, high-quality materials such as polyurethane have been used for the soles of injection molded shoes, but this inevitably results in high costs. The present invention provides low-cost footwear with excellent non-slip properties, and is a polyvinyl chloride resin made of a synthetic resin having a softening point higher than the processing temperature of the polyvinyl chloride composition and a particle size of 100 to 1. Footwear characterized by having a bottom made of a resin layer in which granules are dispersed in 3% or more of the total amount of polyvinyl chloride, and a part of the granules are exposed on the ground-contact side surface of the resin layer. , is the gist. PV used in the present invention
The C layer is prepared by mixing a vinyl chloride homopolymer or a copolymer of vinyl chloride and vinyl acetate, ethylene, or acrylic monomer with appropriate plasticizers, fillers, heat stabilizers, etc., and using a known method, usually at about 150 to 250 minutes. For example, by injection molding, it is integrally molded with the upper part to form the final product of footwear.

The PVC resin raw material is blended with synthetic resin particles. The synthetic resin granules must have a softening point higher than the processing temperature of the PVC layer, and it is desirable that the granules have better wear resistance than the PVC layer. These synthetic resins include polyurethane, nylon 6, nylon 6-6, linear polyesters such as polyethylene terephthalate, acrylic resins such as methyl methacrylate, etc.
BS resin and styrene-butadiene rubber (SBR),
Examples include synthetic rubbers such as isoprene rubber (IR) and butene rubber (BR), and at least one of these synthetic resin particles
seeds are used. Processing conditions are set such that the synthetic resin particles are dispersed in a PVC layer while retaining their original shape by a known method such as injection molding, and are molded with a portion exposed on the surface. The particle size of the granules is 100 to 1
Willow, preferably granules of 140 to 500 Buddhas are used.

Particles with a size of less than 100 mm are too fine for the footwear to exhibit non-slip properties when walking, and are not preferred.

Moreover, if the grain size is more than one grain, it will stay inside the injection machine, and the grains will not be uniformly dispersed in the PVC layer, causing product defects and making it impossible to effectively obtain a good product. The granules are added in an amount of 3% by weight or more, but if the amount is 3% by weight, hardly any non-slip property is exhibited.

Although there is no upper limit, for example, if it is added in an amount of 3% by weight or more, there is almost no difference in the effect. The synthetic resin granules are the PV
Even if it is kneaded with PVC at processing temperature C, the softening point is higher than the processing temperature, so only the surface of the granules softens slightly during processing, and they are not homogeneously miscible, but are dispersed throughout the PVC layer, and a portion of the particles are mixed with PVC. Exposed on the ground surface. Synthetic resin granules with a suitable particle size can be obtained not only by crushing new materials but also by crushing waste tires and plastic waste.

Next, the obtained footwear will be described.

FIG. 1 is a side view of the footwear of the present invention in use.

1 is the upper part, 2 is the PVC layer, 3 is the synthetic resin granules dispersed in the PVC layer, 3' is the synthetic resin granules exposed on both surfaces of the sole of the footwear, 4 is the bottom, and 5 is the ground surface. .

The bottom part 4 is integrally molded with the bottom part 1. The resulting bottom 4
The synthetic resin particles 3 are dispersed in the PVC layer 2, and the synthetic resin particles 3' are exposed on the surface on the ground side. The surface of the granules is then softened and adheres closely to the PVC layer, improving the non-slip properties of the sole of the footwear. Synthetic resin granules 3 exposed on the surface of the sole 4 when actually walking while wearing the footwear of the present invention
The coefficient of friction between ' and the ground contact surface 5 increases significantly, preventing continuous slipping and exhibiting non-slip properties.

An uneven surface may be provided on the ground surface side of the bottom portion 4.

The granules 3 are dispersed throughout the PVC layer 2,
Even if the PVC layer 2 gradually wears out, the particles 3 dispersed within the PVC layer are exposed one after another, and the non-slip properties do not change at all even if the footwear is used for a long time.

In addition, since it is a synthetic resin granule, it blends well with the PVC layer during processing, and the exposed portion does not peel off when walking. In particular, when the granules have better abrasion resistance than the PVC layer 2, the exposed granules 3' do not wear out faster than the PVC layer, which improves durability, which is preferable. The footwear of the present invention exhibits excellent non-slip properties not only when dry but also when leaking water, and its performance does not deteriorate at all even when worn. It also does not cause any wear and tear on the machine. Examples are shown below. Parts are parts by weight. Example
1 Polyvinyl chloride resin (degree of polymerization 1100) 10 Partial plasticizer (DOP) 80 Fatty acid-treated light calcium carbonate 5 Calcium stearate 2 Dibutyltin mercapto polymer 1.5 Higher alcohol-based lubricant
0.5 / Charafe in wax
0.5 Epoxidized soybean oil
2 Processing aid 2 Pigment thermoplastic polyurethane granules 12 The polyurethane granules used in this example have a particle size of 200 to 500 μm and a softening point of 200 q0.

Dry blend the above formulation in a super mixer,
The cylinder temperature is 185qo and the injection pressure is 11500P. S. i. It was injected and integrated with the upper part to manufacture children's shoes. In the resulting shoe sole, polyurethane particles were dispersed throughout the entire thickness of the PVC layer and exposed on the ground surface. Example 2 Vinyl chloride-vinyl acetate copolymer (degree of polymerization 800, vinyl acetate content 5%) 100 parts Plasticizer (DOP) 70 Tribasic lead sulfate 8 Calcium stearate 2 Dibutyltin maleate
15″ high melting point paraffin
0.5 Olefin solvent
0.5 Epoxidized soybean oil
2. Processing aid 2. Face
Appropriate amount of SBR granules
15 parts The SBR granules used in this example are pulverized waste tires and have a softening point of 20 pm and a particle size of 100 to 300 pm.

The above compounded composition was kneaded with a 140qC mixing roll to obtain a 4-leg thick sheet, and then this sheet was made into pellets with a pelletizer and fed to an injection molding machine, and the cylinder temperature was 165°C and the injection pressure was 1000mS. It was injected and integrated with the instep part to manufacture sandals. The resulting sandal sole is P
The SBR particles were dispersed throughout the entire VC thickness and exposed on the ground surface. Example 1 and Example 2
Comparative Examples 1 and 2 were obtained by removing polyurethane granules and SBR granules from the above, and actual walking sliding tests were conducted on wooden floors, PVC sheets, and ceramic tile flooring materials when dry and when water leaked.

We also investigated the actual walking slipperiness when the bottom was sufficiently worn. The results are shown in Table 1.・A Smooth B Slightly slippery.

C. Slips well.

Compared to Comparative Examples 1 and 2, the footwear of the present invention has a wooden floor, a PVC sheet,
In all cases, the ceramic tiles exhibited particularly excellent non-slip performance not only when dry but also when wet.

Furthermore, even when using worn items that have been used for a long time, the synthetic resin granules of the present invention have better wear resistance than PVC, and the granules are always exposed at the bottom. A remarkable difference appeared between 2 and 2.

[Brief explanation of the drawing]

FIG. 1 is a side view of the footwear of the present invention in use. 6 is footwear, 4 is a bottom, and 3, 3 are synthetic resin particles.

Claims (1)

[Scope of Claims] 1. Synthetic resin granules having a softening point higher than the processing temperature of the polyvinyl chloride composition and a particle size of 100 μ to 1 mm are added to the polyvinyl chloride resin in an amount of 3% of the total weight of the polyvinyl chloride.
Footwear characterized by having a bottom made of a resin layer having the above dispersed particles, and a part of the granules being exposed only on the ground-contact side surface of the resin layer. 2. Footwear according to claim 1, wherein the resin granules have better abrasion resistance than polyvinyl chloride.