JPS5851765Y2 - leather shoes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to leather shoes, and particularly to leather shoes in which a heel is sewn from leather with weak subcutaneous tightening tissue and is bonded to a sole material.

Various leathers such as cowhide, horseweed, ragweed, sheepskin, and goatskin are widely used for leather shoe coverings depending on the purpose.

Among these leathers, young cowhide, sheepskin, and goatskin have weak subcutaneous connective tissue, and therefore, the sewage made from these leathers is used to produce cement, sill welt, and vulcanized pressure bonding methods. As shown in FIG. 3, shoes obtained by adhering a sole material using an injection molding method or the like are manufactured by bonding a shoe cover 1 to a sole material 2 using an adhesive. There are many voids 5 in the cover 1 itself, which reduces its strength, and even if the adhesion 4 is sufficient, the cover 1 itself is damaged and its service life is significantly shortened.

In addition, 6 in the figure indicates an insole. Therefore, when making leather shoes with a cover made of young cowhide, sheepskin, or goatskin, the cover and the sole material are sewn into one piece using the bottom stitching methods such as the welt type, the welt type, and the matsukei type, even though they are less efficient. At present, we have been able to obtain durable leather shoes that last a long time.

This invention uses the cement method and Schilwelt method.

When producing leather shoes using the vulcanization bonding method, injection molding method, etc., it has a long service life even if the cover is sewn from leather with weak subcutaneous tightening tissue, such as young cowhide, sheepskin, or goatskin. The purpose is to provide durable leather shoes.

As shown in FIGS. 1 and 2, the leather shoes of the present invention have a shoe cover made of young cowhide, sheepskin, or goatskin with weak subcutaneous connective tissue.
In leather shoes made by pasting with an adhesive, a mixture of a polyurethane prepolymer solution and a crosslinking agent solution for the polymer is infiltrated into the part of the shoe cover 1 where it is attached to the sole material, thereby creating a bond between the fibers. The bridge uses a cover 1 that is connected to the state.

In this case, the mixed liquid 3 must not lose the original flexibility of the coat 1 while bonding the voids 5 between the fibers, and if it hardens to the point where it loses this flexibility, Ba,
Hardening must be avoided as much as possible, as this will halve the original purpose of this invention, which is to prevent the leather shoes from losing their flexibility, and will result in a loss of comfort.

Therefore, as shown by the dotted line in FIG. 2, the bridge is designed to be bonded to the state and leave a gap to ensure that flexibility is maintained.

In carrying out the present invention, a mixture of a polyurethane prepolymer solution and a crosslinking agent for the prepolymer is mixed at a certain ratio, and this is applied to the required areas by spraying, brushing, or other methods to create a coating. Penetrates into the subcutaneous tissue and reinforces the iron part.

The polyurethane prepolymer used here is made by reacting a mixture of polyether glycol or polyester glycol with a hydroxyl value of 50 to 120 and an average molecular weight of 950 to 2,250 and a relatively low molecular weight triol with a naphthalene-based or benzene-based isocyanate. Prepolymers with terminal isocyanate groups are preferred and are used dissolved in a solvent such as xylene or ethyl acetate, while the crosslinking agent is a compound having two or more active hydrogens such as ethylenediamine, tolylenediamine, 44-bis( 2
-chloroaniline) or polyols such as ethylene glycol, diethylene glycol, propylene glycol, etc., dissolved in ketones or other appropriate solvents.

In addition, when polyols are used as crosslinking agents, organic amines such as triethylenediamine, dimethylethanolamine, N-thylmorpholine, etc. or organic salts such as stannath octate, dibutyltin laelate, etc. are added as crosslinking accelerators. do.

For adhesion between the bottom material and the periphery of the undercoat reinforced by the polyurethane prepolymer solution and the crosslinking agent solution for the prepolymer, a material made of acrylnitrbutadiene copolymer rubber, polybutadiene rubber, polychloroprene rubber, etc. is used. Glue is used.

The leather shoes of the present invention obtained as described above are made of leather with a sole material sewn from a leather such as young cowhide, sheepskin, or goatskin, which has large gaps between fibers and has weak subcutaneous compaction tissue. Since the adhesive part is reinforced with polyurethane to the extent that flexibility is not lost, the leather shoes obtained by adhering this part to the sole material with an adhesive will hold up well to young cowhide, sheepskin, and sheepskin even after long-term wear. The original flexibility of leather and goat leather, that is, the feeling of wearing it as a shoe, is maintained, and at the same time, the subcutaneous connective tissue is not destroyed, and the product has a lifespan equal to or longer than that of shoes made using the sole stitching method. Moreover, it has excellent effects in manufacturing, such as not requiring the operator's skill unlike the bottom stitching method.

Example An example for obtaining the leather shoes of the present invention will be shown below.

Acrylic 1 renitrile 4 polymer rubber 10
θ Weight part image Yellow
4 Vulcanization accelerator DM I
t, n// DPG Og 〃// TT 03 t
t Zinc white stearate coumaron resin Anti-aging agent Carbon black Silica filler Activator Part by weight 〃 〃 0! 〃 θ 〃 20 〃 06 〃 Softener 〃 Acrylonitrile-butadiene copolymer rubber is Linac 803 manufactured by Polysar Corporation, Cumaron resin is Cumaron Resin NG manufactured by Mitsubishi Kasei, anti-aging agent is Antigel D manufactured by Ohmukai Shinko Chemical. (Phenyl-β-naphthylamine)
, carbon black is Tokai electrode type sheath) H (HAF
), the silica filler is Tokuyama Soda type Tokusil GU,
Diethylene glycol manufactured by Mitsui Petrochemical Co., Ltd. was used as the activator, and dibutyl phthalate manufactured by Block Chemical Co., Ltd. was used as the softening agent.The mixture was kneaded, aged for one day, rolled, and then cut into the shape of a shoe sole.

About 2,000 parts of a polyester glycol with a hydroxyl value of 50 to 64 and an average molecular weight of about 2,000 obtained by the reaction of adipic acid and diethylene glycol are mixed with about 268 parts of trimethylolpropane and about 1,220 parts of tolylene diisocyanate.
A prepolymer having an isocyanate group at the end is produced by reacting with the prepolymer, and this is dissolved in a mixed solvent of 2,000 parts of toluene and 1,500 parts of ethyl acetate.

Separately, triethylenediamine as a crosslinking agent is dissolved in diethylene glycol to make a 2% solution.

In use, 40 parts of the crosslinker solution are mixed with 1000 parts of the prepolymer solution.

The mixed solution was applied to the area where the lower periphery of the goatskin jacket suspended in the last together with the inner sole, inner core, etc. was attached to the bottom material, and an acrylonitrile butadiene copolymer rubber adhesive was further applied to the upper surface. Apply.

155 side mold for sole mold of vulcanization crimping machine
℃, maintain the pace mold at 165℃, insert an unvulcanized rubber mixture cut into the shape of a shoe sole into the sole mold, and immediately combine the last with a goat leather jacket suspended therein. Heat under pressure for 6 minutes to volatilize the solvent in the mixed solution applied to the area around the lower edge of the goatskin jacket that is attached to the bottom material, and cure the remaining polyurethane without cross-linking.At the same time, the rubber mixture is cured. Vulcanize and manufacture shoes.

A peel test between the sole and the shoe cover of the shoe manufactured in this example was conducted in accordance with JIS, S 5050.713, and the adhesive strength was 20 kg/25 mm.

For reference, only adhesive was applied without applying a mixture of a polyurethane prepolymer solution and a cross-linking agent for the prepolymer to the area where the bottom edge of the shoe was attached to the sole, and the shoes were then bonded using the same vulcanization and crimping machine. was manufactured, and a peel test between the sole and the shoe cover was conducted in accordance with JIS, S 5050.713 in the same way as in this example, but the shoe cover itself broke before the sole and the shoe cover separated. .

[Brief explanation of drawings]

Fig. 1 is a partially cutaway perspective view of the leather shoe of the present invention, Fig. 2 is an enlarged view of the main part A, and Fig. 3 is an enlarged view of the main part of the conventional leather shoe.
In the figure, 1 is a cover, 2 is a bottom material, 3 is a mixed solution of a polyurethane prepolymer solution and the polymer crosslinking agent, 4 is an adhesive, and 5
indicates a void, and 6 indicates an insole.

Claims (1)

[Scope of utility model registration request] In leather shoes which are made of young cowhide leather, sheepskin leather or goat leather with weak subcutaneous tightening tissue and are attached with an adhesive,
A leather shoe characterized by using a shoe cover 1 in which the fibers are bonded in a cross-linked state by infiltrating a mixed solution of a polyurethane prepolymer solution and a cross-linking agent solution for the polymer into the part where it is attached to the sole material. .