JPH06145619A - Tacky adhesive tape and its production - Google Patents

Abstract

PURPOSE:To obtain a tacky adhesive tape unwindable from a roll without causing the breakage between the paper layers of the substrate or between the substrate and the polyethylene laminate layer and exhibiting sufficient tacky adhesive force when used in the packing with a corrugated box and provide a process for the production of the tape. CONSTITUTION:The objective tacky adhesive tape 1 has a peeling force of >=200g/15mm from own back surface. The tacky adhesive force of both edge parts 2a, 2b of the tacky adhesive layer 2 is made to be lower than that of the center part of the tacky adhesive layer 2. The lowering of the tacky adhesive force can be carried out by the application of a releasing agent or the crosslinking or degradation of the tacky adhesive agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive tape and a method for manufacturing the same, and more particularly to a kraft pressure-sensitive adhesive tape which has a large back surface peeling force and can be laminated.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for kraft pressure-sensitive adhesive tapes that can be laminated on each other. Such craft adhesive tape,
A special silicone-based release agent or organic release agent that increases the peeling force on the back surface so that it can be overlaid is applied on the polyethylene laminate layer of the base material. Further, as an adhesive tape that is easily peeled off, a method has been proposed in which the end portion of the tape is a non-adhesive surface (Actual Kaihei 1-830).
No. 43, Jitsukaihei 2-146141).

[0003]

However, in such a kraft pressure-sensitive adhesive tape that can be laminated, such a kraft pressure-sensitive adhesive tape can be used between the layers of the base paper or the base paper when the roll-shaped kraft pressure-sensitive adhesive tape is used. There is a problem that peeling occurs between the polyethylene laminate layer and the polyethylene laminate layer, and it cannot be used as an adhesive tape. This is because the peeling force on the back surface is increased so that the layers can be pasted together. In particular, the cause is that the adhesive strength between the polyethylene laminate layer and the base material is significantly reduced at both ends in the tape width direction. In order to solve such a problem, it is necessary to increase the peel strength of the entire paper more than necessary in order to maintain the strength of both ends in the tape width direction, or to increase the adhesive strength between the base material and the polyethylene laminate layer. There wasn't. Further, the method described in the above publication has the effect of preventing peeling between the paper base material or between the paper base material and the polyethylene laminate layer, but often causes peeling from the end surface after attachment. Further, in such a method, it is necessary to apply the adhesive in a streak shape, which is complicated in the manufacturing process. Further, it becomes necessary to align the position of the blade with the portion not coated with the adhesive when cutting or slitting.

The object of the present invention is to solve the above-mentioned conventional problems and develop a tape without the problem of delamination even if the interlaminar strength of the base paper and the adhesive strength with the polyethylene laminate layer are not particularly enhanced. An object of the present invention is to provide a pressure-sensitive adhesive tape and a manufacturing method thereof.

[0005]

The adhesive tape of the present invention has an adhesive layer provided on a kraft paper substrate and has a self-backside peeling force of 2
The adhesive tape is 00 g / 15 mm or more, and is characterized in that the adhesive force at both end portions of the adhesive layer in the tape width direction is made lower than the adhesive force at the central portion of the inside adhesive layer.

The method for producing the adhesive tape of the present invention is
After forming the pressure-sensitive adhesive layer on one surface of the substrate, by applying a release agent to both ends of the pressure-sensitive adhesive layer in the tape width direction, or by crosslinking or degrading the pressure-sensitive adhesive at both ends of the pressure-sensitive adhesive layer. , The adhesive strength of both ends of the adhesive layer in the tape width direction,
It is lower than the adhesiveness of the central part of the adhesive layer inside thereof.

In the present invention, it is preferable that the both ends in the tape width direction that reduce the adhesive strength are within 2 mm from both edges in the tape width direction. In the manufacturing method of the present invention, after the pressure-sensitive adhesive layer is formed on one surface of the base material, the treatment for lowering the pressure-sensitive adhesive strength is performed. One method of reducing the adhesive strength is to apply a release agent to both ends of the adhesive in the tape width direction. This can be performed by continuously applying a release agent to both ends of the adhesive layer in the tape width direction. Such a release agent can be applied, for example, at the time of slitting. Further, as another method of reducing the adhesive force, there is a method of crosslinking or degrading the adhesive in the adhesive layer at both ends in the tape width direction. Such crosslinking or deterioration can be performed by UV, EB (electron beam), heat or the like. Such treatment can be performed during slitting or after cutting.

[0008]

According to the present invention, the adhesive force at both ends of the adhesive layer in the tape width direction is made lower than the adhesive force at the central portion, so that the adhesive tape can be used in a developed state. It is possible to obtain a kraft pressure-sensitive adhesive tape that does not break between the paper layers of the material or between the base paper and the polyethylene laminate layer.

In the present invention, after the pressure-sensitive adhesive is applied over the entire surface of the substrate, the release agent is applied only to the portion where the adhesive strength is desired to be reduced, or the pressure-sensitive adhesive in that portion is crosslinked or deteriorated. According to the present invention, since the pressure-sensitive adhesive can be applied to the entire surface of the substrate in this manner, the thickness of the tape after applying the pressure-sensitive adhesive is uniform in the width direction, and the subsequent processing step is easy. There is no risk of wrinkles. According to the present invention, a kraft pressure-sensitive adhesive tape that can be overlaid and that does not cause damage when the tape is developed can be provided without complicating the manufacturing process.

[0010]

EXAMPLE According to the present invention, as shown in FIG. 1, both ends 2a and 2 of the adhesive layer 2 of the adhesive tape 1 in the tape width direction are shown.
The adhesive force of the portion b is made lower than the adhesive force of the central portion of the adhesive layer 2 inside thereof.

FIG. 2 is a sectional view of the pressure-sensitive adhesive tape shown in FIG. 1. The pressure-sensitive adhesive tape 1 is provided with an adhesive layer 2 on one side of a Clupak kraft paper base 5 and a polyethylene laminate layer 3 on the other side. The mold release agent layer 4 is formed on the polyethylene laminate layer 3. Such a release agent layer 4
Can be formed from an organic release agent, a modified silicone release agent, or the like. Hereinafter, the present invention will be described with reference to specific examples. Hereinafter, parts mean parts by weight.

Example 1 Polyethylene was laminated on one surface of a 73 g / m ² Kurupack kraft paper substrate to a thickness of 18 μm to form a polyethylene laminate layer. On this polyethylene laminate layer, a release agent (trade name; Peeloyl 1010, manufactured by Yushisha Kogyo Co., Ltd.) was applied at 0.02 g / m ² to form a release agent layer. 100% natural rubber adhesive (natural rubber TPCIX: 100 parts, resin Alcon P-70: 80 parts, solvent toluene: 500 parts) on the opposite side
It is coated and dried so that it becomes g / m ^2, and then 50
A piece of silicone emulsion (trade name: K), which is a release agent, is cut into a size of 2 mm × 40 cm, and 2 mm from both ends in the width direction of the adhesive layer of the kraft adhesive tape.
M-740, manufactured by Shin-Etsu Chemical Co., Ltd.) was applied. In this way, the obtained adhesive tape was used to seal a cardboard (length × width × height: 300 × 250 × 500) on the I-stick. In addition, a sample was prepared in which the pressure-sensitive adhesive coated surface was attached to the release surface.

Comparative Example 1 In the kraft pressure-sensitive adhesive tape having the structure of Example 1, the pressure-sensitive adhesive tape not coated with the pressure-sensitive adhesive was applied to both ends of the widthwise direction of 10 mm.
I sealed the sticker. In addition, a sample was prepared in which the release surface was attached to the pressure-sensitive adhesive application surface.

Comparative Example 2 An adhesive tape was produced in the same manner as in Example 1 except that the Kraft adhesive tape having the structure of Example 1 was prepared by applying no release agent to both ends in the width direction. did.

Using the pressure-sensitive adhesive tape obtained, in the same manner as in Example 1, a corrugated cardboard was I-sealed and sealed. In addition, a sample was prepared in which the pressure-sensitive adhesive coated surface was attached to the release surface.
As described above, the corrugated cardboard sealed with the adhesive tapes of Example 1 and Comparative Examples 1 and 2 was left in a room at 30 ° C. for 1 week, and the peeled state was observed. The number of samples was set to 20, and the percentage of the corrugated cardboard that had peeled off the sealed part after 1 week was shown in Table 1 as the cardboard peeling rate (%).

The 180 ° peel force is 30 g /
After applying a load of cm ² and leaving it in an oven at 60 ° C. for 1 week, it was peeled off at a speed of 60 m / min and measured. The results are shown in Table 1. In addition, the state of breakage occurring at both ends of the substrate when the adhesive tape was unrolled from the roll was observed. With the number of samples being 50, Table 1 shows the rate of occurrence of breakage at the edges of the substrate.

[0017]

[Table 1]

As is clear from Table 1, the adhesive tape of Example 1 according to the present invention had a high peeling force of 180 ° peel, and did not cause breakage at the end of the base material during deployment, and sealed the cardboard. The peeling rate was also low.

[Brief description of drawings]

FIG. 1 is a perspective view showing an adhesive tape according to the present invention.

FIG. 2 is a sectional view of the adhesive tape shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Adhesive tape 2 ... Adhesive layer 3 ... Polyethylene laminate layer 4 ... Release agent layer 5 ... Curupack kraft paper substrate

Claims (2)

[Claims] 1. An adhesive layer is provided on a kraft paper substrate,
In a pressure-sensitive adhesive tape having a self-back peeling force of 200 g / 15 mm or more, the pressure-sensitive adhesive force at both ends of the pressure-sensitive adhesive layer in the tape width direction is lower than the pressure-sensitive adhesive force at the central portion of the pressure-sensitive adhesive layer inside thereof. Yes, adhesive tape. 2. A method for producing a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed on one surface of a kraft paper substrate and a release agent layer formed on the other surface, the self-backside peeling force being 200 g / 15 mm or more. After forming the pressure-sensitive adhesive layer on one surface of the base material, a release agent is applied to both ends of the pressure-sensitive adhesive layer in the tape width direction, or the pressure-sensitive adhesive at both ends of the pressure-sensitive adhesive layer is crosslinked or deteriorated. The pressure-sensitive adhesive tape manufacturing method is characterized in that the pressure-sensitive adhesive force at both ends of the pressure-sensitive adhesive layer in the tape width direction is made lower than the pressure-sensitive adhesive force at the central portion of the pressure-sensitive adhesive layer inside thereof.