JPH0420601B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method of forming a non-slip shoe sole. (Prior art) Conventionally, according to Utility Model Application Publication No. 62-21904, glass fibers are mixed with unvulcanized rubber and rolled, so that the glass fibers are oriented in the rolling direction. A shoe sole has been proposed in which anti-slip pieces are layered several times and then cut in a direction perpendicular to the rolling direction, and then embedded and molded into the ground contact surface of the sole, with the cut surface serving as the ground contact surface. In this sole, the glass fibers interposed in the anti-slip piece are arranged perpendicularly to the ground surface, resulting in a sole with excellent anti-slip properties, but the forming of the anti-slip piece is complicated. It had to be molded into the sole of the shoe, which had the disadvantage of increasing costs. The applicant has investigated various methods of injection molding shoe soles using a shoe sole molding material that is a mixture of vinyl chloride resin and glass fiber, but the soles obtained in this way quickly harden at low temperatures below 0°C. It has the disadvantage of losing flexibility and becoming slippery. (Problems to be Solved by the Invention) The present invention aims to provide a shoe sole that exhibits excellent anti-slip properties even at low temperatures of 0° C. or lower, by an extremely simple method and at a low cost. (Means for solving the problem) This invention will be explained below with reference to the drawings.
This invention consists of 100 parts by weight of vinyl chloride resin and a plasticizer.
70 to 150 parts by weight and hard fibers with a length of 0.1 mm to 10 mm 5
A shoe sole molding material consisting of ~50 parts by weight and ² to 20 parts by weight of acrylic resin and having a melt index of 20 to 50 g/10 minutes is injected into a shoe sole molding cavity at an injection pressure of 600 to 1000 kg/cm2. The gist of the invention is a method for molding a characteristic anti-slip shoe sole. In this invention, the vinyl chloride resin includes vinyl chloride resin, vinylidene chloride resin, vinyl chloride/vinylidene chloride copolymer resin, vinyl chloride/vinyl acetate copolymer resin, vinyl chloride/ethylene copolymer resin, and vinyl chloride resin. - One or a mixture of two or more of maleic anhydride copolymer resin, vinyl chloride propylene copolymer resin, etc. is used. The plasticizers used in this invention are those normally used in vinyl chloride resins, such as dioctyl phthalate, dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, dinonyl phthalate, and diisodecyl phthalate. Phthalate ester plasticizers such as phthalate, ditridecyl phthalate, and dicyclohexyl phthalate; linear hydrochloric acid esters such as dioctyl adipate, dioctyl azelate, and dioctyl sebacate;
Phosphate esters such as tricresyl phosphate and tricylenyl phosphate, plasticizers such as castor oil derivatives, epoxidized vegetable oils, and polyester plasticizers may be used alone or in combination of two or more. The amount of plasticizer added was limited to 70 to 150 parts by weight per 100 parts by weight of the vinyl chloride resin. Not only does the mechanical strength decrease, but it becomes even softer at high temperatures and the surface becomes viscous, making it unsuitable for shoe soles.Additionally, if the amount added is less than that, it becomes hard, lacks flexibility, and has impact resistance. This is because the properties of the material are significantly reduced, making it unsuitable for use as shoe soles. In this invention, as the hard fiber, one or a mixture of two or more of inorganic fibers such as glass fiber, rock wool, rock wool, quartz fiber, silica fiber, crustonite fiber, and ceramic fiber, metal fiber, and carbonaceous fiber is used. Ru. If these hard fibers are surface-treated with a titanium-based coupling agent, a silane-based coupling agent, a fatty acid, a fatty acid metal salt, a fatty acid ester, etc., their adhesion and dispersibility with vinyl chloride resin can be improved. . In this invention, the length of hard fibers is limited to 0.1 mm to 10 mm, and the amount of hard fibers is
The reason for limiting it to 5 to 50 parts by weight per 100 parts by weight is that if the fiber length and blending amount are less than this, the fluidity of the sole molding material in the sole molding cavity during injection molding will be better. If the length and amount of fibers are too long, the hard fibers will be oriented parallel to the contact surface of the sole, reducing the slip resistance of the resulting shoe sole. At times, the fluidity of the sole molding material in the sole molding cavity is significantly reduced, causing insufficient filling of the sole molding material into the sole molding cavity, and the soles molded in this way lack a design. This is because sink marks and flow marks are formed on the surface of the material, which significantly deteriorates its appearance. In this invention, acrylic resins are used as modifiers and processability improvers for vinyl chloride resins, and examples of acrylic resins include methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, and hydroxyl methacrylate. Methacrylic acid esters such as ethyl methacrylate, acrylic acid esters such as methyl acrylate, 2-ethylhexyl acrylate, n-butyl acrylate and hydroxyethyl acrylate, methacrylic acid or acrylic acid, acrylamide or methacrylamide derivatives such as n-butoxymethylmethacrylamide Polymers or copolymers made from monomers such as In addition to the above monomers, copolymerization components include maleic dimethacrylate, itaconic acid, α-methylene glutaric acid, aconitic acid, or ester derivatives or amides of these acids.
Styrene, styrene derivatives such as α-methylstyrene, acrylonitrile, methacrylonitrile,
Or a combination of two or more of these may be used. In this invention, the amount of acrylic resin to be blended is based on 100 parts by weight of vinyl chloride resin.
The reason for limiting the amount to 2 to 20 parts by weight is that if the amount is less than that, hard fibers will be included in the sole molding material, and the sole molding material will not be used in the sole molding cavity during injection molding. The fluidity of the molding material decreases significantly, causing insufficient filling of the sole molding material into the sole molding cavity, and the soles molded in this way may lack design or have sink marks or flow marks on the surface. formed and its appearance deteriorates significantly,
Moreover, there is no improvement effect on cold resistance in terms of physical properties, and it becomes hard at temperatures below 0°C, loses flexibility, reduces flexibility, becomes uncomfortable, and becomes slippery. If the temperature is higher than that, the cold resistance of the sole will be improved, but the dispersibility of the acrylic resin in the vinyl chloride resin will be poor, resulting in poor moldability, and the hardening of the molded sole will vary widely, resulting in a uniform This is because there is a drawback that it is not possible to obtain a suitable product. A foaming aid, a stabilizer, a filler, a lubricant, a coloring agent, etc. may be added to the shoe sole molding material of the present invention, if necessary. Each ingredient prepared in this way is
Mix uniformly using a Banbury mixer, Henschel mixer, mixing roll, kneader, etc. to bring the melt index of the shoe sole molding material to 20 to 50.
Prepare to adjust to g/10 minutes. The reason why the melt index of the sole molding material is limited to 20 to 50 g/10 minutes in this invention is that if the melt index is lower than this, the fluidity of the sole molding material in the sole molding cavity during injection molding will be reduced. This results in a significant decrease in the sole molding material, which causes insufficient filling of the sole molding material into the sole molding cavity, and the soles molded in this way may lack design or have sink marks or flow marks formed on the surface, resulting in a significant change in appearance. If the melt index is higher than that, the fluidity of the sole molding material in the sole molding cavity during injection molding will be too good, and the hard fibers will be oriented in parallel directions along the contact surface of the sole. This is because there is a drawback that the anti-slip properties of the resulting shoe sole are reduced. The sole molding material prepared in this way has an injection pressure of
The sole molding material is injected into the sole molding cavity at a pressure of 600 to 1000 kg/ ^cm2 , but if the injection pressure is lower than that, the fluidity of the sole molding material in the sole molding cavity during injection molding will be affected. This results in a significant decrease in the sole molding material, which causes insufficient filling of the sole molding material into the sole molding cavity, and the soles molded in this way may lack design or have sink marks or flow marks formed on the surface, resulting in a significant change in appearance. If the injection pressure is lowered or exceeded, the flow of the sole molding material in the sole molding cavity will become turbulent, the flow direction will not be fixed, and the orientation of the hard fibers mixed in the sole molding material will be affected. This is because the particles are not fixed and are scattered irregularly throughout the shoe sole, making it difficult to expect the sole to be anti-slip. (Operations and Effects of the Invention) The present invention is constructed as described above, and the sole formed in this manner has hard fibers oriented in a direction substantially perpendicular to the ground contact surface, and has excellent slip resistance. It was warm. Moreover, even at low temperatures of 0° C. or lower, the hardness changes are small and appropriate flexibility and flexibility are maintained, so the anti-slip properties are not reduced. Furthermore, injection molding allows the hard fibers to be oriented substantially perpendicularly to the contact surface of the sole at the same time as the sole is formed, making the sole molding extremely inexpensive. In this invention, the reason why the hard fibers are oriented almost perpendicularly to the contact surface of the sole during injection molding is due to the limited range of melt index of the sole molding material and the limited range of melt index during injection molding. Due to the interaction of the injection pressure, the sole molding material flows in the thickness direction of the sole molding cavity as shown in the drawing during injection molding, and is filled into the sole molding cavity. This is thought to be because the hard fibers blended into the sole molding material are oriented along the flow direction of the sole molding material. Example Shoe sole moldings having the formulations according to Examples 1 to 3 shown in the upper row of Table 1 were prepared, and formed by a bottom mold 1, side molds 2, 2, and a last 3 in which a shoe cover 5 was suspended. Shoe soles obtained by injecting into a molded shoe sole molding cavity 4 at an injection temperature of 195° C. and an injection pressure of 800 kg/cm ² and foaming the same, and soles obtained in the same manner according to Comparative Examples 1 and 2. Anti-slip property, 0℃~20℃
Hardness difference (JISK6301 Spring type hardness test A
A comparison of the differences in hardness depending on the mold and the appearance revealed that the soles molded according to the examples shown in the lower row of Table 1 exhibited the desired effects of the present invention.

【table】

【table】 [Brief explanation of drawings]

The drawing is a sectional view of a main part showing a state of molding a shoe sole according to the present invention. Explanation of the symbols: 1...Bottom mold, 2...Side mold, 3...Last, 4...Sole molding cavity, 5...Shoe cover.

Claims (1)

[Claims] 1 100 parts by weight of vinyl chloride resin and 70 to 150 parts of plasticizer
A shoe sole molding material consisting of 5 to 50 parts by weight of hard fibers with weight parts and lengths of 0.1 mm to 10 mm and 2 to 20 parts by weight of acrylic resin, and a melt index of 20 to 50 g/10 minutes, is injected at 600 to 600 parts. A method for molding anti-slip shoe soles characterized by injecting 1000 kg/cm ² into a shoe sole molding cavity.