JPH0210191B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) This invention relates to a peripheral rubber tape for footwear. In the manufacture of footwear, especially shoes, a rubber circumferential tape is generally attached to the lower circumferential edge of the shoe cover.
This part is being reinforced. (Prior art) Conventionally, rubber compounding chemicals such as stearic acid, activated zinc white, vulcanization accelerator, sulfur, filler, etc. are added to the natural or synthetic rubber shown in Table 1 (a). An unvulcanized rubber footwear circumferential tape was prepared by sheeting and cutting to a certain width. Then, on one side of the footwear circumferential rubber tape prepared in this way, an ordinary rubber adhesive 4 shown in Table 1 (c) is applied and dried, and this is applied in advance in the footwear manufacturing process as shown in Figure 4. Adhesive similar to the above (called hanging glue 5)
is applied and dried by hand and crimped around the bottom of the cover, and then heated using a conventional method to create rubber tape and unvulcanized rubber that is separately adhered to the underside of the cover. The soles were vulcanized to complete the footwear. However, when adhering the rubber tape to the bottom of the footwear in the footwear manufacturing process, a rubber adhesive layer (suspension layer) is applied to a constant width around the bottom of the footwear, corresponding to the width of the rubber tape. However, it is difficult to completely cover this hanging glue layer and attach the rubber tape to the specified position around the bottom of the cover by hand, and the hanging glue layer is not placed above the rubber tape. exposed,
For this reason, during the rubber tape crimping operation, the hanging glue 51 exposed above the rubber tape contaminates the laces, resulting in a disadvantage that the appearance of the finished footwear is significantly degraded. (Problems to be Solved by the Invention) The present invention aims to eliminate these drawbacks, provide a peripheral rubber tape for footwear that has excellent adhesive strength with the shoe cover, and has a good appearance. (Means for Solving the Problems) In the present invention, on one side 11 of the unvulcanized rubber tape 1, 10 to 20 parts by weight of a blocking isocyanate compound and 10 to 20 parts by weight of liquid polyisoprene rubber are added to 100 parts by weight of ordinary rubber. The gist of the invention is a peripheral rubber tape for footwear, characterized in that an adhesive layer 2 is formed by adding a rubber compound and other compounded chemicals commonly used in rubber. In the present invention, the unvulcanized rubber tape 1 is formed mainly from one or a mixture of two or more synthetic natural rubbers such as IR, SBR, NBR, and CR. In the present invention, the adhesive layer 2
The normal rubbers that make up are natural rubber IR,
One or a mixture of two or more synthetic rubbers such as SBR, NBR, and CR are used. In this invention, as the blocked isocyanate compound, for example, the following diisocyanate compounds blocked with the following blocking agents are used. Examples of diisocyanate compounds include ethylene diisocyanate, propylene diisocyanate, tetromethylene diisocyanate, hexamethylene diisocyanate, decamethylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, naphthylene diisocyanate, 4-4' ethylene bis(phenyl isocyanate), ω. ω'-diisocyanate-1,3-dimethylbenzene, ω・ω'-diisocyanate-
1,4-dimethylbenzene, 1-methyl-2,4
―Diisocyanate cyclohexane, ω・ω′―
Diisocyanate diethylbenzene, ω・ω′-
Diisocyanate dimethyltoluene, ω・ω′-
Diisocyanate diethyltoluene, ω・ω′-
Diisocyanate dimethylxylene, ω・ω′-
Diisocyanate diethylxylene, ω・ω′-
Diisocyanate dimethylcyclohexane, 4,
Diisocyanate compounds such as 4'methylene-bis(cyclohexyl isocyanate), 4-4'-ethylene-bis(cyclohexyl isocyanate), isophorone diamine diisocyanate, lysine diisocyanate, an excess of the above diisocyanate compounds, ethylene glycol, propylene glycol, 1, Examples include diisocyanate compounds obtained by addition reaction with low molecular weight diols such as 3-butylene glycol and neopentyl glycol. Examples of blocking agents include alcohols such as methanol, ethanol, ethoxyethanol, and methoxyethanol, aromatic amines such as diphenylamine and xylidine, imides such as succinimide and phthalic acid imide, and activated methylene such as acetylacetone and diethyl malonate. Blocking agents include lactams such as ε-caprolactam and butyrolactam, phenols such as phenol, cresol and p-hydroxymethylbenzoate, oximes such as cyclohexane oxime and methyl ethyl ketone oxime, imines, and ureas. These blocked isocyanate compounds are heated to 120°C to 170°C,
The blocking agent is dissociated from the compound and activated into an isocyanate compound having an active isocyanate group. These blocked isocyanate compounds are appropriately selected and used depending on the vulcanization temperature of the rubber tape 1, and those whose isocyanate groups are reactivated at a temperature equal to or lower than the vulcanization temperature of the rubber tape 1. In this invention, the amount of blocking isocyanate compound is limited to 10 to 20 parts by weight per 100 parts by weight of rubber in the formulation constituting the adhesive layer 2. If the amount is less than that, the rubber tape 1 The adhesive strength with the cover 3 will decrease, and if the amount is more than that, the heating during vulcanization will cause
This is because the adhesive layer 2 is discolored and the blocking isocyanate compound itself is expensive, resulting in an increase in costs. In this invention, the liquid isoprene rubber is preferably an isoprene polymer, maleic anhydride, isoprene polymer modified with a functional group such as carboxyl, and has an average molecular weight of 10,000 to 60,000. If the average molecular weight is less than that, adhesive layer 2
The viscosity of the rubber tape 1 may become low, causing adhesion of the rubber tape 1 to slip when crimping the rubber tape 1.
There is a tendency for the adhesive strength between the and the cover 3 to decrease,
Moreover, if the average molecular weight is higher than that, the viscosity of the adhesive layer 2 becomes high, the anchoring ability of the adhesive layer 2 to the clasp 3 decreases, and the adhesive strength of the rubber tape 1 to the clasp 3 tends to decrease. In the present invention, the amount of liquid polyisoprene rubber in the formulation constituting the adhesive layer 2 is limited to 10 to 20 parts by weight per 100 parts by weight of ordinary rubber. For example, there are disadvantages in that the anchoring ability of the adhesive layer 2 to the cover 3 decreases, and the adhesive strength of the rubber tape 1 to the cover 3 decreases, and if the blending amount is more than that, the viscosity of the adhesive layer 2 becomes low. When rubber tape 1 is crimped, rubber tape 1
This is because there are disadvantages in that adhesive slippage occurs and the adhesive strength between the rubber tape 1 and the sleeve 3 decreases. The adhesive layer 2 may be formed on the unvulcanized rubber tape 1 by lamination molding at the time of sheeting the unvulcanized rubber tape 1, or by cutting and forming the unvulcanized rubber tape 1 in advance under the shoe cover 3 during the footwear manufacturing process. It may be applied and molded immediately before being attached to the periphery. The adhesive layer 2 formed on one side of the rubber tape 1 is reactivated with a solvent or the like immediately before being attached to the lower periphery of the tape cover 3, if necessary. Example An adhesive having a composition shown in Table 1(b) was applied to one side 11 of a rubber tape 1 formed according to a composition shown in Table 1(a).
One sheet of rubber tape was laminated to a thickness of 0.5 mm and cut to an appropriate width to prepare a peripheral rubber tape for footwear of the present invention. The peripheral rubber tape for footwear of the present invention prepared as described above was applied to the lower periphery of the shoe cover 3 without applying hanging glue and the side surface of the unvulcanized rubber sole by reactivating the adhesive layer 2 with toluene. , pasted by hand, and crimped with a pressure of 5 kg/cm ² using a crimping device.
After that, it is introduced into a vulcanization can by a conventional method,
The rubber tape 1 and the unvulcanized rubber sole were vulcanized by heating and pressurizing at 130° C. and 3.5 kg/cm ² for 60 minutes, and the peripheral rubber tape for footwear of the present invention was attached to complete footwear.

【table】

[Table] (Effects of the invention) Footwear completed by pasting the circumferential rubber tape for footwear of the present invention and footwear completed by pasting the conventional peripheral rubber tape for footwear by the conventional method, there was Table 2 shows a comparison of the adhesive strength between Rubber Tape No. 3 and Rubber Tape No. 1. As is clear from Table 2, in the present invention, a peripheral rubber tape for footwear was obtained which had superior adhesive strength between the sleeve 3 and the rubber tape 1 compared to the conventional example. The cause of this is that the liquid polyisoprene rubber blended into the adhesive layer 2 formed on one side of the rubber tape 1 has good fluidity, which makes the rubber tape 1 difficult to cover.
When pressure-bonding the adhesive layer 2, a part of the adhesive layer 2 is well anchored in the tissue gap of the cover 3, and the blocking isocyanate compound compounded in the adhesive layer 2 is blocked by heating during vulcanization. In combination with the reactivation of isocyanate groups, rubber tape 1
It is thought that the adhesion strength between the material and the cover 3 is enhanced. Furthermore, when the peripheral rubber tape for footwear of the present invention is attached to the lower periphery of the shoe cover 3, the hanging glue for the shoe cover 3 is omitted, so the footwear manufacturing process is simplified, and the shoe cover 3 is contaminated by the hanging glue. The appearance of the footwear is good.

【table】 [Brief explanation of drawings]

The drawings show examples, and FIG. 1 is a cross-sectional view of a main part of the peripheral rubber tape for footwear of the present invention, and FIG. 2 is a sectional view of the peripheral rubber tape for footwear of the present invention. It is a sectional view of the main part of the attached footwear,
FIG. 3 is a sectional view of a main part of a conventional peripheral rubber tape for footwear, and FIG. 4 is a sectional view of a main part of footwear to which the peripheral rubber tape for footwear of FIG. 3 is attached by a conventional method. Explanation of symbols, 1...Rubber tape, 11...Single side, 2
...Adhesive layer, 3...Cover, 4...Adhesive, 5...Hanging glue,
51...Exposed hanging glue.

Claims (1)

[Claims] 1 On one side 11 of unvulcanized rubber tape 1, 10 to 20 parts by weight of a blocking isocyanate compound and 10 parts by weight of liquid polyisoprene rubber are added to 100 parts by weight of ordinary rubber.
A peripheral rubber tape for footwear, characterized in that an adhesive layer 2 is formed by adding ~20 parts by weight and other compounded chemicals commonly used in rubber.