JPH0425585A - Decorative rubber tape for foot gear - Google Patents

Abstract

PURPOSE:To obtain the title rubber tape excellent in adhesion to the upper and appearance by forming a specific adhesive layer on one surface of an unvalcanized rubber tape. CONSTITUTION:An adhesive layer comprising a composition containing 100 pts.wt. rubber (e.g. isoprene rubber), 3-9 pts.wt. block isocyanate compound (e.g. Uroc Q900 made by Hirono Chemical Co.) and 25-50 pts.wt. liquid isoprene rubber is formed on one side of an unvalcanized rubber tape.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a decorative rubber tape for footwear used for reinforcing the lower periphery of a shoe flap.

(Prior Art) A conventional method for decorating the lower periphery of the footwear with a decorative rubber tape for footwear includes, for example, using natural or synthetic rubber as the main ingredient, and adding stearic acid, activated zinc white, a vulcanization accelerator, etc.
After adding rubber compounding chemicals such as sulfur and fillers and sheeting, an unvulcanized rubber tape is prepared by cutting this into a fixed width, and then a rubber adhesive is applied to one side of this unvulcanized rubber tape. After drying, an adhesive similar to this rubber adhesive (hereinafter referred to as upper glue) is applied, and it is pasted and pressed by hand to the lower periphery of the dried cover. This is heated by a heating means to vulcanize the unvulcanized rubber tape and the unvulcanized rubber sole, which is separately adhered to the lower surface of the shoelace, thereby reinforcing the lower peripheral edge of the shoelace.

However, in order to adhere the unvulcanized rubber tape to the lower periphery of the laces of footwear, upper glue is applied to the lower periphery of the laces in a constant width corresponding to the width of the unvulcanized rubber tape to form an upper glue layer. It is often difficult to form the upper glue layer, completely cover the upper glue layer, and apply unvulcanized rubber tape precisely by hand at specified positions on the lower edge of the upper cover. Since the glue layer is exposed above the rubber tape, the upper glue is contaminated by the glue exposed above the rubber tape during the rubber tape crimping process, which significantly deteriorates the appearance of the footwear, and furthermore, there is a problem in that the adhesive strength deteriorates. It had

As a method to solve these conventional problems, for example, on one side of an unvulcanized rubber tape, for every 100 parts by weight of rubber,
Decorative rubber tapes for footwear have been proposed in which an adhesive layer is formed from a composition containing 10 to 20 parts by weight of a blocked isocyanate compound and 10 to 20 parts by weight of liquid polyisoprene rubber.

[Problems to be Solved by the Invention] However, even in the above-mentioned decorative rubber tape for footwear, the high content of blocked isocyanate compounds speeds up the reaction and reduces adhesion, as well as the content of liquid polyisoprene rubber. At present, good adhesion cannot be obtained because the viscosity increases due to the small amount and the tackiness decreases.

The present invention was made against the background of such conventional technology, and makes it possible to improve the adhesion to the cover, and
To provide a decorative rubber tape for footwear with a good appearance.

[Failure to solve the problem]

The present invention provides an adhesive layer made of a composition containing 3 to 9 parts by weight of a blocked isocyanate compound and 25 to 50 parts by weight of liquid polyisoprene rubber, based on 100 parts by weight of rubber, on one side of an unvulcanized rubber tape. The present invention provides a decorative rubber tape for footwear characterized by the following:

Hereinafter, an example of the present invention will be described in detail based on the drawings.

Figures 1 and 2 show an example of the decorative rubber tape for footwear of the present invention, and the decorative rubber tape A for footwear includes a block on one side 11 of an unvulcanized rubber tape 100 with respect to 100 parts by weight of rubber. The adhesive layer 20 is formed of a composition containing 3 to 9 parts by weight of an isocyanate compound and 30 to 50 parts by weight of liquid polyisoprene rubber, and this decorative rubber tape A for footwear is applied to footwear such as shoes. It is attached to the lower periphery 31 of the cover 30 to reinforce it.

The unvulcanized rubber tape 10 referred to in the present invention refers to natural rubber, isoprene rubber (IR), styrene-butadiene rubber (S
BR), acrylonitrile-butadiene rubber (NBR)
, chloroprene rubber (CR), etc., or a mixture of two or more thereof as a main component.

In addition, the thickness of the unvulcanized rubber tape 10 is 1.0 to 2.0
Approximately mm is preferable.

The rubber constituting the adhesive layer 20 formed on one side 11 of the unvulcanized rubber tape 10 may be natural rubber (NR) or TR.
, SBR, NBR, CR, etc., or a mixture of two or more thereof can be used, but IR is most preferable from the viewpoint of adhesive properties.

Note that the thickness of the adhesive layer 20 is preferably about 0.1 to 0.5 mm.

The blocked isocyanate compound referred to in the present invention includes, for example, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, decamethylene diisocyanate,
Phenyl diisocyanate, tolylene diisocyanate, naphthylene diisocyanate, 4-4' ethylene bis(phenylisocyanate), ω・ω'-diisocyanate, 1.3-dimethylbenzene, 14-dimethylhensen, 1-methyl-24-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, 4,4′-methylene-bis(cyclohexyl isocyanate), 4,4-ethylene-bis(cyclohexyl isocyanate), isophorone diamine diisocyanate An isocyanate such as a diisocyanate obtained by the addition reaction of an excess of a diisocyanate compound such as lysine diisocyanate with a low molecular weight diol such as ethylene glycol, propylene glycol, 13-butylene glycol, or neopentyl glycol, in methanol, ethanol, or Alcohols such as I-xyethanol and methoxyethanol, aromatic amines such as diphenylamine and xylidine, imides such as succinimide and phthalic acid imide, active methylene compounds such as acetylacetone and diethyl malonate, ε-cafrolactam and butyrolactam. caprolactams such as phenol, cresol, P-
These blocked isocyanate compounds are blocked with blocking agents such as phenols such as hydroxymethyl benzoate, oximes such as cyclohexane oxime and methyl ethyl ketoxime, imines, and ureas. These blocked isocyanate compounds are heated to 120 to 170°C. The blocking agent is dissociated from the compound and activated into an isocyanate compound having an active isocyanate group.

Further, these blocked isocyanate compounds are appropriately selected and used, depending on the vulcanization temperature of the unvulcanized rubber tape 10, and those whose isocyanate groups are reactivated at a temperature equal to or lower than the vulcanization temperature of the unvulcanized rubber tape 10.

In the present invention, the amount of the blocked isocyanate compound constituting the adhesive layer 20 is 3 to 9 parts by weight, preferably 4 to 6 parts by weight, based on 100 parts by weight of the rubber constituting the adhesive layer 20. If the amount is less than 3 parts by weight, the reaction progresses slowly, while if it exceeds 9 parts by weight, the reaction is too fast to obtain the desired adhesiveness, and the blocked isocyanate compound itself is expensive, resulting in an increase in cost. .

On the other hand, liquid isoprene rubber is an isoprene polymer modified with functional groups such as maleic anhydride, carbosyl, etc., and has an average molecular weight of 10,000 to 10,000.
60,000 is preferable, and the average molecular weight is 10.0.
If the viscosity is less than 00, the viscosity of the adhesive layer 20 will be too low, and the adhesion of the decorative rubber tape A for footwear will occur when the decorative rubber tape A for footwear is pressed, or the adhesive strength between the decorative rubber tape A for footwear and the shoe cover 30 will be reduced. Moreover, if the average molecular weight exceeds 60,000, the viscosity of the adhesive layer 20 becomes high, and the anchoring effect of the adhesive layer 20 to the laces 30 decreases, and the laces 30 of the decorative rubber tape A for footwear tend to deteriorate. There is a tendency for the adhesive strength to decrease.

The amount of liquid polyisoprene rubber constituting the adhesive layer 20 is 25 to 50 parts by weight, preferably 30 to 40 parts by weight, based on 100 parts by weight of the rubber constituting the adhesive layer 20. If the adhesive layer 20 is less than 100%, the viscosity becomes high and the adhesiveness decreases, and the desired anchoring effect of the adhesive layer 20 to the laces 30 cannot be obtained.
On the other hand, if the amount exceeds 50 parts by weight, the compound becomes sticky and difficult to handle.

The adhesive layer 20 formed on one side 11 of the unvulcanized rubber tape 10 may be laminated during sheeting of the unvulcanized rubber tape 10, or the unvulcanized rubber tape 1O, which has been cut in advance, may be formed in a footwear manufacturing process. The lower periphery 3 of the cover 30
It may be attached immediately before attaching to 1.

Further, the adhesive layer 20 formed on one side 11 of the unvulcanized rubber tape 10 may be reactivated with a solvent or the like immediately before being attached to the lower peripheral edge 31 of the tape cover 30, if necessary.

[Effect]

As described above, the decorative rubber tape for footwear of the present invention contains a large amount of liquid polyisoprene rubber and a small amount of a blocked isocyanate compound in the adhesive layer formed on one side of the rubber tape.

For this reason, the amount of liquid polyisoprene rubber blended into the adhesive layer formed on one side of the rubber tape is large.
The viscosity decreases and the adhesiveness becomes stronger, increasing the anchoring effect, so when pressing the rubber tape onto the tape, a part of the adhesive layer is anchored well in the tissue gap of the tape, and during vulcanization. When heated, the blocked isocyanate groups of the blocked isocyanate compound blended into the adhesive layer are reactivated, and the reaction rate is reduced due to the small amount of blocked isocyanate compound blended. It becomes possible to improve adhesiveness.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 A rubber tape (thickness 1.
5 mm), an adhesive having the composition shown in Table 1 (a) D is laminated to a thickness of 0.2 nm during rubber tape sheeting to form an adhesive layer, and this is cut to an appropriate width to form a decorative rubber tape for footwear. I got it.

The thus obtained decorative rubber tape for footwear was reactivated with toluene and attached by hand to the lower periphery of the upper shoe, which omitted the application of glue, and to the side surface of the unvulcanized rubber sole. After crimping with a pressure bonding device at a pressure of 5 kg/cii, this was introduced into a vulcanization can using a conventional method.
The rubber tape and the unvulcanized rubber sole were cured by heating and pressurizing at 30°C and an air pressure of 3.0 kg/cj for 60 minutes to complete footwear equipped with the decorative rubber tape for footwear of the present invention.
The adhesive strength of the decorative tape for footwear was measured according to IS K2SO3. The results are shown in Table 2.

*1) Nylock Q-906, manufactured by Hirono Chemical Industry ■ (liquid polybutadiene is made into urethane prepolymer with TDI,
In addition, active isocyanate groups are blocked with phenols) *2) LIR-30 (manufactured by Clareisoprene Chemical ■,
Liquid polyisoprene rubber comparative example 1 Footwear equipped with a decorative rubber tape for footwear was completed in the same manner as in Example 1 except that the adhesive composition was changed to the one shown in Table 1 Φ). The adhesive strength of decorative tape for footwear was measured.

The results are shown in Table 2.

As is clear from Table 2, when the decorative rubber tape for footwear of this example was used, it was found that the adhesive strength between the shoe cover and the decorative rubber tape for footwear was excellent.

[Effects of the Invention] Since the present invention is configured as described above, it is possible to provide a decorative rubber tape for footwear that can improve adhesiveness to a shoe cover and has a good appearance.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the main parts of the decorative rubber tape for footwear of the present invention;
FIG. 2 is a cross-sectional view of a main part of a shoe in which a decorative rubber tape is attached to the lower circumferential edge of the heel of the footwear. A: Decorative rubber tape for H objects 10: Unvulcanized rubber tape 20: Adhesive layer 30: Patent applicant Achilles Co., Ltd. Agent Patent attorney Takashi Shirai Shige

Claims (1)

[Claims] (1) On one side of the unvulcanized rubber tape, form an adhesive layer made of a composition containing 3 to 9 parts by weight of a blocked isocyanate compound and 25 to 50 parts by weight of liquid polyisoprene rubber per 100 parts by weight of rubber. Decorative rubber tape for footwear characterized by: