JPH06228513A - Double-coated pressure-sensitive adhesive tape and its production - Google Patents

Abstract

PURPOSE:To provide a tape protected from fluffing in punching by using a nonwoven fabric which is mainly made of synthetic resin fibers and in which the fibers are partially fused to each other as a substrate and forming adhesive layers on both surfaces of this substrate. CONSTITUTION:The apparatus used consists of a winding 1 of a substrate, lead-on rolls 2 and 4, a pair of laminating rolls 3, and a pair of transfer rolls 6. An example of the nonwoven fabric (a) to be used as a substrate is a nonwoven fabric of polyethylene terephthalate. By the transfer coating process comprising the steps of: applying a pressure-sensitive adhesive (e.g. acrylic one) solution to a release sheet (b) prepared by laminating polyethylene films on both surfaces of kraft paper, forming silicone release layers on both surfaces and drying the applied solution to form a pressure-sensitive adhesive layer (c) on the release sheet b, and laying the release sheet (b) on which the pressure-sensitive adhesive layer (c) is formed on one surface of the substrate, while laying another release sheet (b) on which a pressure- sensitive adhesive layer (c) is formed on the other surface of the substrate, forming pressure- sensitive adhesive layers of a thickness of 60mum on both surfaces of the nonwoven fabric (a), and winding the double-coated nonwoven fabric into a roll in which the pressure-sensitive adhesive face is situated inside each turn while the release sheet (b) is removed from the back surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided pressure-sensitive adhesive tape having a non-woven fabric containing synthetic resin fibers as a main component as a base material and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, various non-woven fabrics have been used as a base material.
It is well known that a double-sided pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is formed on both sides of the base material is used ("Adhesive Handbook, First Edition": edited by the Japan Adhesive Tape Industry Association, March 1985).
Issued March 2, 380-385).

Further, we have reported a method for producing a double-sided pressure-sensitive adhesive tape by a transfer method, which has good punching workability and prevents wrinkles from being formed on the wound body, using a non-woven fabric containing hemp as a main component as a base material ( Japanese Patent Application No. 3-304734).

[0004]

A double-sided adhesive tape having a non-woven fabric as a base material is used when a name plate is fixed to an OA equipment body or the like. As a usage method, a double-sided pressure-sensitive adhesive tape is once attached to a sheet material to be a nameplate, and then punched into a desired shape to form a nameplate in which the double-sided pressure-sensitive adhesive tape is laminated, and the nameplate is attached to an OA device body. Take the process of.

However, when the main body of the OA device to be pasted is colored, especially in a dark color such as black, the cut portion of the punched non-woven fabric is fluffed.

[0006] If the fluff of the above-mentioned non-woven fabric protrudes from between the name plate and the adherend, the non-woven fabric becomes conspicuous because it is white, and there is a problem that the appearance quality is significantly impaired.
As a method for solving such a problem, a means for making the non-woven fabric black is also conceivable, but using a non-woven fabric having a color matching the color of the adherend main body has a special specification, resulting in high cost and Since the lot size must be manufactured above a certain level, there is a problem that waste is increased.

Japanese Patent Application No. 3-304734 also has an effect as a manufacturing method in which wrinkling does not occur, but the rigidity of hemp fibers suppresses the basis weight of the hemp base material and the tension of the nonwoven fabric. There was a constraint on the manufacturing conditions that the adhesive on the release sheet had to be transferred in a stretched state, and there was a point that it was not sufficient yet.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a double-sided pressure-sensitive adhesive tape based on a non-woven fabric, which does not cause fuzz at all during punching. It is to be. Furthermore, wrinkles do not occur even if the manufacturing conditions are not particularly limited,
It is an object of the present invention to provide a method for producing a double-sided pressure-sensitive adhesive tape based on a non-woven fabric, which satisfies the above characteristics.

[0009]

As a result of earnest observation and examination, the present inventor has found that the cause of the above problems is as follows.

That is, in a non-woven fabric which is usually used, fibers are bonded to each other by a certain kind of binder, and the bonding between fibers by such means is unavoidably weak, and the fibers come off due to some external stress. For this reason, when punched out, the fiber cut portion comes off and floats, which causes fluffing.

The cause of wrinkling is due to the lack of stretchability of the nonwoven fabric substrate. For example, in the case of a non-woven fabric containing hemp as a main component, when it is wound around a paper core or the like to form a wound body, the inner base material layer follows the release sheet on the outer side of the wound body. Because it does not, wrinkling occurs.

The present invention has been made as a result of intensive research to solve the above problems. That is, claim 1 is characterized by comprising a synthetic resin fiber as a main component, a non-woven fabric formed by partially heat-bonding fibers of each other as a base material, and forming an adhesive layer on both surfaces of the base material. It is a double-sided adhesive tape.

According to a second aspect of the present invention, there is provided a step of laminating a release sheet having a pressure-sensitive adhesive layer formed on one surface of a base material, and a step of forming a pressure-sensitive adhesive layer on the other surface side of the base material. A double-sided pressure-sensitive adhesive tape manufacturing method comprising a step of winding a layer inside, wherein the base material is a nonwoven fabric in which synthetic resin fibers are a main component, and fibers are partially heat-sealed. Is a method for producing a double-sided adhesive tape.

As the base material of the double-sided pressure-sensitive adhesive tape used in the present invention, a synthetic resin fiber is used as a main component, and a non-woven fabric in which fibers are partially heat-sealed is used. The non-woven fabric is usually a sheet-like member made by treating various fiber pieces mechanically, chemically, thermally or a combination thereof and bonding the constituent fibers to each other by an adhesive or the fusion force of the fibers themselves. The non-woven fabric used in the present invention is obtained by partially fusing the fibers of the synthetic resin by the thermal means in the above manufacturing method.

As the synthetic resin fiber that can be used, a synthetic resin having thermoplasticity or thermosetting property can be used as a raw material, but it is preferable to use a thermoplastic resin which is convenient for heat fusion. As the thermoplastic resin, for example, polyolefin, polyamide, polystyrene, polyester, polyvinyl chloride, etc. can be mentioned, but they have toughness and flexibility as fibers, low hygroscopicity, and excellent wrinkle resistance. Therefore, polyester can be preferably used.

A non-woven fabric can be obtained by heating and fusing together the short pieces of the synthetic fiber. The thickness of the non-woven fabric is not particularly limited depending on the application, but is 3
0 to 200 μm, preferably 50 to 150 μm. The basis weight is 10 to 100 g, preferably 2
0-50g is mentioned.

Further, in terms of product quality, the strength of the base material is at least 0.5 in both the longitudinal and transverse directions.
A width of at least 15 kg / 15 mm, preferably a width of at least 1 kg / 15 mm can be mentioned.

The pressure-sensitive adhesive used in the present invention is not particularly limited, and examples thereof include acrylic-based, urethane-based, rubber-based, and styrene-based pressure-sensitive adhesives depending on the application. The thickness of these pressure-sensitive adhesive layers is not particularly limited, but is 20 to 20 as the thickness on one side.
0 μm can be mentioned.

Further, examples of the method of applying the pressure-sensitive adhesive include a method of directly applying the pressure-sensitive adhesive to the base material and a transfer method in which the pressure-sensitive adhesive is once formed on the release sheet and then applied to the base material. However, according to the method of the invention of claim 2,
After the step of laminating a release sheet having a pressure-sensitive adhesive layer formed on one surface of a substrate and the pressure-sensitive adhesive layer formed on the other surface of the substrate, the pressure-sensitive adhesive is wound inside.

That is, the pressure-sensitive adhesive layer on the other side of the substrate is formed by a transfer method in which the pressure-sensitive adhesive is formed on the release sheet as in the case of the one side of the substrate, and then applied to the substrate. Then, the pressure-sensitive adhesive layer is formed by a method of directly coating the base material.

The release sheet is not particularly limited as long as it is a support sheet having releasability, depending on the application. For example, a commonly used release sheet is kraft paper with polyethylene on both sides. An example is a laminated type in which a silicone release layer is provided on one or both sides.

The double-sided pressure-sensitive adhesive tape prepared by the above method is usually formed into a laminated body having a release sheet attached to one side or both sides, and wound around a paper core and stored as a wound body.

[0023]

In the base material of the double-sided pressure-sensitive adhesive tape of the present invention, since the synthetic resin fibers are fused by heat, the fibers do not easily come loose even when an external force is applied.

Further, since the synthetic resin fibers are heat-sealed to each other and the gap is not filled with the binder, the synthetic resin fibers have many gaps and the degree of impregnation with the adhesive is high. Further, since the synthetic resin fibers are not adhered to each other by the binder, they are not affected by the solvent and other substances from the adhesive.

Further, the non-woven fabric base material whose main component is the heat-sealed synthetic resin fiber has elasticity and can follow the release sheet and the pressure-sensitive adhesive layer located outside.

[0026]

EXAMPLES Examples of the present invention will be described below. FIG. 1 shows a method for producing a double-sided pressure-sensitive adhesive tape in an example and a structure of a double-sided pressure-sensitive adhesive tape produced by the method. Reference numeral 1 is a base material roll, 2 and 4 are feed rolls, 3 is a laminating roll, 6 is a transfer roll, 5 is a laminate, and 7 is a double-sided pressure-sensitive adhesive tape on which a single-sided release sheet is laminated.

A non-woven fabric composed of polyethylene terephthalate (a product of Hirose Paper Co .: 05TH24, 05TH3 as a non-woven fabric a whose main component is a synthetic resin fiber which is heat-sealed.
On a release sheet b (San A Chemical Co., Inc., WHT-80A) in which the acrylic adhesive solution (SKDINE 1717 manufactured by Soken Chemical Co., Ltd.) is laminated on both sides of kraft paper with polyethylene using the base material of 6). Then, a step of applying and drying to form the pressure-sensitive adhesive layer c, and superimposing the release sheet b on which the pressure-sensitive adhesive layer c is formed, and the pressure-sensitive adhesive layer c was formed again on the other surface of the non-woven fabric a substrate. 60 μm by a transfer-type coating method including a step of overlapping release sheets b
After forming a thick pressure-sensitive adhesive layer on both surfaces of the nonwoven fabric a, the release sheet b was peeled off and wound with the pressure-sensitive adhesive surface facing inward. In the manufacturing process, the release sheet b on which the pressure-sensitive adhesive layer c was formed was not overlapped in the stretched state of the nonwoven fabric a, but was bonded in a normal state.

As a comparative example, a nonwoven fabric made of pulp / rayon (SPC manufactured by Nippon Paper Industry Co., Ltd., # 80 manufactured by Miki Paper Co., Ltd.)
1), Washi paper (manufactured by Daifuku Paper Co., Ltd .: DP base paper), and a non-woven fabric made of Manila hemp (manufactured by Nippon Paper Industries Co., Ltd .: F base paper),
A pressure-sensitive adhesive layer having a thickness of 60 μm was formed on both surfaces of the above nonwoven fabric by the same method as in the example, and then the release sheet b was peeled off and wound with the pressure-sensitive adhesive surface inside.

(Evaluation of the degree of wrinkling) By the above method,
The obtained double-sided pressure-sensitive adhesive tape was wound around a 3-inch paper core for 20 m with the pressure-sensitive adhesive side inside, and left at room temperature for 24 hours,
The following evaluations were made by visually evaluating the presence or absence of creases in the pressure-sensitive adhesive layer c near the paper core.

◯: No crease was observed. Δ: A few creases were observed. X: A large number of wrinkles were observed.

(Evaluation of Occurrence of Fluffing) The double-sided pressure-sensitive adhesive tape obtained by the above method was attached to a hard vinyl chloride resin plate, the release sheet was peeled off, and another hard vinyl chloride was attached to the other pressure-sensitive adhesive surface. A sandwich structure in which resin plates were stuck together was punched out with a press machine, and the following evaluation was performed by visually evaluating the presence or absence of fuzz formation from the cut surface.

◯: No fuzz was observed at all. Δ: Some fuzz was observed. X: Fuzz was considerably observed.

(Evaluation of interlaminar strength between base material layer and pressure-sensitive adhesive layer) The double-sided pressure-sensitive adhesive tape obtained by the above method was attached to a steel plate, the release sheet was peeled off, and a polyester film was attached to the other pressure-sensitive adhesive surface. After pasting and pressure bonding with a 2 kg roller, aging at 60 ° C for 1 hour, then at room temperature for 1 hour
After leaving for a week, the tape was forcibly peeled off, and the state of the peeled surface was visually evaluated to perform the following evaluations.

◯: The entire surface of the adhesive layer was peeled off from the steel plate interface. Δ: A part of the pressure-sensitive adhesive layer caused interlaminar failure, resulting in adhesive residue phenomenon. X: Interlaminar failure occurred on the entire surface of the pressure-sensitive adhesive layer, and the adhesive residue phenomenon occurred.

Table 1 shows the constitution of each of the obtained double-sided pressure-sensitive adhesive tapes and the evaluation results thereof.

[0036]

[Table 1]

As is clear from the examples of Table 1, synthetic resin fibers (polyester) which are heat-sealed as a non-woven fabric.
It is clear that the product using is excellent in both the degree of wrinkling, the occurrence of fuzz and the interlaminar strength of the adhesive.

As a comparative example, the one using a non-woven fabric (pulp / rayon, Japanese paper, Manila hemp) produced by using an ordinary binder or the like is inferior in both the occurrence of fuzz and the interlaminar strength of the adhesive.

Regarding those using Manila hemp,
In the manufacturing method that does not use particularly limited manufacturing conditions, wrinkling has occurred. Further, also in the adhesive residue phenomenon, a non-woven fabric (pulp / rayon, Japanese paper, Manila hemp) produced by using an ordinary binder or the like.
Those that use are inferior.

[0040]

As described above in detail, according to the double-sided pressure-sensitive adhesive tape of the present invention, the non-woven fabric used as the base material contains the synthetic resin as the main component, and the fibers are partially heat-sealed. Therefore, even if an external force is applied, the fibers do not easily loosen, so that no fluff occurs during punching.

Further, since the non-woven fabric is composed of synthetic resin fibers as a main component and the fibers are partially heat-sealed together, it is flexible and can relieve the strain applied from the outside.

As a result, in a manufacturing method including a step of laminating a release sheet having a pressure-sensitive adhesive layer formed on at least one surface of a substrate, and winding the pressure-sensitive adhesive layer formed on the other surface of the substrate inside. Without the need for particularly limited conditions,
It is possible to obtain a double-sided pressure-sensitive adhesive tape in which the base material and the pressure-sensitive adhesive layer do not wrinkle.

Furthermore, since there are many gaps between the synthetic resin fibers and the degree of impregnation of the pressure-sensitive adhesive is high, the interlayer adhesion between the non-woven fabric substrate layer and the pressure-sensitive adhesive layer is high, and as a result, the interlaminar failure phenomenon is eliminated.

[Brief description of drawings]

FIG. 1 is an explanatory view of an example used in the method for producing a double-sided adhesive tape of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material roll 2, 4 Feed roll 3 Laminating roll 5 Laminating body 6 Transfer roll 7 Double-sided adhesive tape a Nonwoven fabric b Release sheet c Adhesive layer

Claims (2)

[Claims] 1. A non-woven fabric comprising synthetic resin fibers as a main component, and fibers of which are partially heat-sealed together as a base material, and an adhesive layer is formed on both sides of the base material. Double-sided adhesive tape. 2. A step of laminating a release sheet having a pressure-sensitive adhesive layer formed on one surface of a base material, and forming a pressure-sensitive adhesive layer also on the other surface side of the base material, and then making the pressure-sensitive adhesive layer inside. A double-sided pressure-sensitive adhesive tape manufacturing method comprising a step of winding and winding, wherein the base material is a non-woven fabric in which synthetic resin fibers are a main component and fibers are partially heat-sealed. Manufacturing method.