JP2002235051A - Method for producing double-sided pressure-sensitive adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a double-sided pressure sensitive adhesive tape having excellent operating efficiency and capable of reducing the cost with stabilized quality. SOLUTION: This method for producing the double-sided pressure-sensitive adhesive tape comprises simultaneously carrying out inline a step A of forming release agent layers on both surfaces of a substrate for a release liner and preparing the release liner, a step B of forming adhesive mass layers on both surfaces of the substrate for the double-side pressure-sensitive adhesive tape and preparing a double-sided pressure-sensitive adhesive layer and a step C of laminating the release liner to the double-sided pressure-sensitive adhesive tape layer and preparing the double-sided pressure-sensitive adhesive tape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a double-sided pressure-sensitive adhesive tape capable of improving workability and stabilizing quality.

[0002]

2. Description of the Related Art In general, a double-sided adhesive tape is formed by applying an adhesive to both sides of a base material such as paper, plastic, or metal.
A release liner in which a release agent is applied to both surfaces of a sheet of paper, plastic, metal, or the like is attached to this. Conventionally, as shown in FIGS. 5 to 8, such a double-sided pressure-sensitive adhesive tape has been coated with a pressure-sensitive adhesive using a release liner previously manufactured in a separate process to produce a double-sided pressure-sensitive adhesive tape. . Specifically, in FIG. 5, an adhesive (18) is applied to a release liner (17) prepared in advance by a coater (21) (first adhesive application), and a drying oven (22) is applied. After passing
Intermediate product (20) in which a bonding machine (23) is bonded to a substrate (19), an adhesive is applied to one surface of the substrate (19), and a release liner layer is provided on the adhesive layer.
Has been produced. Next, as shown in FIG. 6, a process paper (having the same release function as a release liner, and a release liner is usually used) (24) prepared in advance is coated with a coater (27). , An adhesive (25) is applied (the second application of the adhesive),
After passing through the drying oven (28), the adhesive layer (25)
Side and the surface of the intermediate product (20) on the substrate (19) side are bonded by a bonding machine (29), and the process paper (24a) is wound up to form a double-sided adhesive tape. (26) is manufactured. Further, the intermediate product (20) produced according to FIG. 5 can also be used by a method as shown in FIG. In FIG. 7, the adhesive (3) is directly applied to the intermediate product (20) by the coater (32).
(0) (the second application of the adhesive), and a drying oven (33) to produce a double-sided adhesive tape (31).

In the method shown in FIGS. 5 to 7, the first pressure-sensitive adhesive and the second pressure-sensitive adhesive are applied and the first pressure-sensitive adhesive is applied even though a release liner prepared in advance is used. Two steps of forming a layer and a second pressure-sensitive adhesive layer are required. That is, this method requires two steps of applying a pressure-sensitive adhesive on both sides.

As shown in FIG. 8, an adhesive (36) is applied to one surface of a substrate (35) by a coater (39), and an adhesive (36) is applied to the other surface by a coater (40). 37) in the same process and drying oven (4
After 1), there is also a method of producing a double-sided pressure-sensitive adhesive tape (38) by laminating with a release liner (34) by a laminating machine (42). However, even in this method, in any case, the step of preparing the release liner and the step of applying the pressure-sensitive adhesive are separate steps.

Therefore, in the manufacturing method shown in FIGS. 5 to 8, the workability is low and the manufacturing cost is high. In particular, the manufacturing method requiring the process paper (24) shown in FIG. 6 further increases the cost.

[0006] In general, the release force of the release liner is liable to change depending on humidity and temperature over time from the time it is manufactured to the time it is used, and in some cases, the release liner may cause abnormal release. Sometimes. Therefore, when preparing a double-sided pressure-sensitive adhesive tape using a release liner that has been prepared in advance, it is difficult to control the release liner from the time it is manufactured to the time it is used. For example, a heavy peeling phenomenon due to exposure to the atmosphere, a change in peeling property due to a aging reaction of silicone, and the like are likely to occur.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for producing a double-sided pressure-sensitive adhesive tape which is excellent in workability and can reduce the production cost. Another object of the present invention is to provide a manufacturing method capable of easily manufacturing a double-sided pressure-sensitive adhesive tape having a stable quality.

[0008]

Means for Solving the Problems The present inventor has made intensive studies to achieve the above object, and as a result, by combining specific steps and performing them in-line at the same time, excellent workability and low cost have been achieved. It has been found that a double-sided pressure-sensitive adhesive tape can be easily produced with stable quality, and the present invention has been completed.

That is, the present invention comprises a step A of forming a release liner by forming a release agent layer on both sides of a release liner substrate, and forming an adhesive layer on both sides of a double-sided pressure-sensitive adhesive tape substrate The step B of preparing a pressure-sensitive adhesive tape layer and the step C of bonding the release liner and the double-sided pressure-sensitive adhesive tape layer to prepare a double-sided pressure-sensitive adhesive tape are a method for producing a double-sided pressure-sensitive adhesive tape, which is simultaneously performed in-line.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings as needed. FIG. 1 is a schematic view showing an example of the method for producing a double-sided pressure-sensitive adhesive tape of the present invention. In FIG. 1, 1 is a base material for a release liner, 2 is a release agent (first release agent), 3 is a release agent (second release agent), 4 is a release liner, 5 is a base material for a double-sided adhesive tape, 6 is An adhesive (first adhesive), 7 is an adhesive (second adhesive), 8 is a double-sided adhesive tape layer, and 9 is a double-sided adhesive tape. 10 is a coater (coater for a first release agent), 11 is a coater (coater for a second release agent), 12 is a drying oven (dry oven for a release liner), 13 is a coater (coater for a first adhesive), 14 is a coater (coater for the second adhesive), 15
Is a drying oven (drying oven for double-sided adhesive tape), 1
6 is a bonding machine.

In the manufacturing method according to FIG. 1, [Step A] a first release agent (2) is applied to one surface of a release liner substrate (1).
Is applied with a first release agent coater (10) to form a first release agent layer, and the other surface is coated with a second release agent (3) using a second release agent coater (11). Step A of forming a release liner having a release agent layer formed on both sides of a release liner substrate (1) by drying in a drying oven for release liner (12) after forming a release agent layer.
And [Step B] a first pressure-sensitive adhesive (6) on one surface of the base material (5) for a double-sided pressure-sensitive adhesive tape (13).
To form a first pressure-sensitive adhesive layer, and apply a second
The pressure-sensitive adhesive (7) is applied by a coater for a second pressure-sensitive adhesive (14) to form a second pressure-sensitive adhesive layer, and then dried by a drying oven for a double-sided pressure-sensitive adhesive tape (15) to form a substrate for a double-sided pressure-sensitive adhesive tape ( 5) Step B of preparing a double-sided pressure-sensitive adhesive tape layer (8) having a pressure-sensitive adhesive layer formed on both sides thereof, and [Step C] a surface of the release liner (4) on the first release agent (2) side; The surface of the double-sided pressure-sensitive adhesive tape layer (8) on the side of the first pressure-sensitive adhesive (6) is bonded to prepare a double-sided pressure-sensitive adhesive tape (9) in which a release liner (4) and a double-sided pressure-sensitive adhesive tape layer (8) are bonded. Step C is simultaneously performed in-line to produce a double-sided pressure-sensitive adhesive tape.

(Step A) In step A, a release liner (4) composed of three layers as shown in FIG. 2 is produced. In FIG. 2, 1a is a base material for a release liner (1).
2a is a first release agent layer composed of the first release agent (2), and 3a is a second release agent layer composed of the first release agent (2).
It is a second release agent layer composed of a release agent (3).

(Base layer for release liner (1a)) Step A
Then, as the release liner substrate (1) of the release liner substrate layer (1a), a long strip-shaped sheet or film (particularly, a long strip-shaped sheet or film wound into a roll) is used. Can be used. By using the base material (1) for a release liner in such a form, the base material (1) for a release liner can be continuously supplied, and the release liner (4) can be manufactured continuously.

In the present invention, the width and length of the release liner substrate (1) are not particularly limited, and are appropriately selected according to the production machine, the intended width and length of the release liner (4), and the like. be able to. Also, the thickness of the release liner substrate (1),
That is, the thickness of the release liner substrate layer (1a) is not particularly limited, either, but can be selected, for example, from the range of about 10 to 200 μm. For example, when the material of the release liner substrate (1) is a plastic film shown below, the thickness of the release liner substrate (1) is 1
It can be selected from a range of about 2 to 100 μm (preferably 25 to 75 μm). When the material of the release liner substrate (1) is paper, the thickness of the release liner substrate (1) is 30 to 200 μm (preferably 70 to 200 μm).
150 μm).

The material for the release liner substrate (1) is not particularly limited, and a known release liner substrate material can be used. Examples of the material of the release liner substrate (1) include papers (for example, paper such as high-quality paper, glassine paper, kraft paper, and a laminate in which one or both sides of paper are laminated with a polymer material such as polyethylene. Paper, etc., metal foil (for example, aluminum foil, copper foil, stainless steel foil, iron foil, etc.), plastic film (for example, olefinic resin such as polyethylene and polypropylene, and thermoplastic resin such as polyvinyl chloride, polyester and polyamide) And the like). The material for the release liner substrate (1) can be used alone or in combination of two or more. The release liner substrate layer (1a) may be a single layer or a multiple layer.

(Release Agent Layers (2a, 3a)) First Release Agent Layer (2a) and Second Release Agent Layer (3a) (These release agent layers are collectively referred to simply as “release agent layers (2a, 3a)”). May be applied to another surface of the release liner base material layer (1a) by the first release agent coater (10) or the second release agent coater (11). 2) or second
The release agent (3) is applied and formed. Coater for first release agent (10) and coater for second release agent (11)
(These coaters may be collectively referred to simply as “coaters for release agent”) as a first release agent (2) or a second release agent.
The coater is not particularly limited as long as it can apply the release agent (3) to the release liner substrate (1), and a known coater can be used. As the release agent coater, a coater capable of continuously applying the release agent to the release liner substrate (1) is preferable. Specifically, as a coater for a release agent, for example, gravure reverse, wire bar, kiss reverse and the like can be suitably used. The first coater for release agent (10) and the coater for second release agent (11) may be of the same type or different types.

A first release agent (2) and a second release agent (3)
(These release agents may be simply referred to as “release agents (2, 3)” in some cases.) There is no particular limitation, and known release liner release agents can be used. Release agent (2
As 3), for example, a polymer having a long-chain alkyl group,
Release agents such as silicone polymers (silicone-based release agents) and fluorine-based polymers (fluorine-based release agents) are exemplified. These release agents can be used alone or in combination of two or more. The first release agent (2) and the second release agent (3) may be the same release agent or different release agents.

In the present invention, the release liner (4) preferably has different release forces on both surfaces. That is, there is a difference in the peeling force with respect to the double-sided pressure-sensitive adhesive tape layer (8) between the surface on the first release agent layer (2a) side and the surface on the second release agent layer (3a) side of the release liner (4). Is preferred. Therefore, it is preferable that the first release agent (2) and the second release agent (3) are a combination of release agents that exhibit at least different release forces. The first release agent (2) of the first release agent layer (2a) to be bonded to the double-sided pressure-sensitive adhesive tape layer (8) in step C generally has a release force larger than that of the second release agent (3). A release agent that can be developed is used.

It is preferable that the release liner (4) can be easily released from the double-sided pressure-sensitive adhesive tape layer (8). Therefore, as the release agent (2, 3),
Silicone release agents are preferred.

Therefore, it is preferable that the first release agent (2) and the second release agent (3) each use a silicone release agent capable of expressing different release forces.
Examples of the silicone-based release agent include a thermosetting silicone-based release agent (for example, a condensation-reaction-type thermosetting silicone-based release agent, an addition-reaction-type thermosetting silicone-based release agent, etc.), and a radiation-curable silicone-based release agent. A release agent (for example, an electron beam-curable silicone-based release agent, an ultraviolet-curable silicone-based release agent, etc.) is exemplified. Each of these silicone-based release agents includes those having a releasability capable of exhibiting various release forces, from those having a large release force and heavy release properties to those having a small release force. In.

The amount of the release agent (2, 3) applied, that is, the thickness of the release agent layer (2a, 3a) is not particularly limited, and the type of the release agent (2, 3) and the intended release liner It can be appropriately selected according to (4) and the like. As the thickness of the release agent layer (2a, 3a), for example,
It can be selected from the range of 0.01 to 5 μm (preferably 0.03 to 3 μm). The first release agent layer (2
The thickness of a) and the thickness of the second release agent layer (3a) may be the same or different.

A known drying oven can be used as the drying oven (12) for the release liner used for drying the release liner substrate (1) coated with the release agent (2, 3). Drying oven for release liner (12)
Can be appropriately selected according to the type of the release agent (2, 3) and the like. In the drying by the release liner drying oven (12), if necessary, for example, when a thermosetting silicone-based release agent is used as the release agent, a curing reaction relating to the release agent may be performed. .

When an electron beam-curable silicone-based release agent or an ultraviolet-curable silicone-based release agent is used as the release agent, the drying oven (12) for the release liner is changed to an electron beam irradiation system or an ultraviolet irradiation system. can do.

(Step B) In step B, a double-sided pressure-sensitive adhesive tape layer (8) composed of three layers as shown in FIG. 3 is prepared. In FIG. 3, 5a is a double-sided pressure-sensitive adhesive tape base layer composed of a double-sided pressure-sensitive adhesive tape base (5), 6a.
Is a first pressure-sensitive adhesive layer composed of the first pressure-sensitive adhesive (6), 7
a is a second pressure-sensitive adhesive layer composed of the second pressure-sensitive adhesive (7).

(Substrate layer for double-sided pressure-sensitive adhesive tape (5a)) In step B, the base material for double-sided pressure-sensitive adhesive tape (5) of the substrate layer for double-sided pressure-sensitive adhesive tape (5a) is a long strip-shaped sheet or A film (especially, a long strip-shaped sheet or film wound into a roll) can be used. By using the double-sided pressure-sensitive adhesive tape base material (5) in such a form, the double-sided pressure-sensitive adhesive tape base material (5) is continuously supplied,
The layer for double-sided pressure-sensitive adhesive tape (8) can be continuously produced.

In the present invention, the substrate for double-sided pressure-sensitive adhesive tape (5)
Is not particularly limited, and can be appropriately selected according to the production machine, the width and length of the target double-sided pressure-sensitive adhesive tape layer (8), and the like. In addition, base material for double-sided adhesive tape (5)
The thickness of the substrate layer for double-sided pressure-sensitive adhesive tape (5a) is not particularly limited, either.
(Preferably 12 to 50 μm).

The material for the base material (5) for a double-sided pressure-sensitive adhesive tape is not particularly limited, and a known base material for a double-sided pressure-sensitive adhesive tape can be used. Examples of the material of the base material (5) for a double-sided pressure-sensitive adhesive tape include papers such as Japanese paper and Western paper, nonwoven fabrics, metal foils such as aluminum foil, plastic films such as polyester films, and foam sheets. The material for the substrate (5) for a double-sided pressure-sensitive adhesive tape can be used alone or in combination of two or more.
Further, the base layer (5a) for a double-sided pressure-sensitive adhesive tape may be a single layer or a multilayer.

(Pressure-sensitive adhesive layers (6a, 7a)) First pressure-sensitive adhesive layer (6a) and second pressure-sensitive adhesive layer (7a) (these pressure-sensitive adhesive layers are collectively referred to simply as "pressure-sensitive adhesive layers (6a, 7a)"). May be applied to the other surface of the double-sided pressure-sensitive adhesive tape base layer (5a) by using a first pressure-sensitive adhesive coater (13) or a second pressure-sensitive adhesive coater (14). (6) Or the second adhesive (7) is applied and formed. Coater for first adhesive (13), coater for second adhesive (14)
(These coaters are sometimes simply referred to as “coaters for pressure-sensitive adhesives”) as the first pressure-sensitive adhesive (6) or the second pressure-sensitive adhesive.
The coater is not particularly limited as long as the adhesive (7) can be applied to the base material (5) for a double-sided adhesive tape, and a known coater can be used. As the pressure-sensitive adhesive coater, those capable of continuously applying the pressure-sensitive adhesive to the base material (5) for a double-sided pressure-sensitive adhesive tape are preferable. Specifically, as a coater for the adhesive, for example, a gravure coater,
A roll knife coater, knife coater, slot die coater and the like can be suitably used. As a coater for an adhesive, a slot die coater is preferable in consideration of uniform coatability. The first coater for pressure-sensitive adhesive (13) and the coater for second pressure-sensitive adhesive (14) may be of the same type or different types.

The first adhesive (6) and the second adhesive (7)
(These adhesives may be simply referred to as “adhesives (6, 7)” in some cases) are not particularly limited, and known adhesives for double-sided adhesive tapes can be used. Examples of the pressure-sensitive adhesive (6, 7) include pressure-sensitive adhesives such as an acrylic pressure-sensitive adhesive, a natural rubber-based pressure-sensitive adhesive, a synthetic rubber-based pressure-sensitive adhesive, and a silicone-based pressure-sensitive adhesive. These pressure-sensitive adhesives can be used alone or in combination of two or more. The first adhesive (6) and the second adhesive (7) may be the same adhesive or different adhesives.

The coating amount of the pressure-sensitive adhesive (6, 7), that is, the thickness of the pressure-sensitive adhesive layer (6a, 7a) is not particularly limited, and the type of the pressure-sensitive adhesive (6, 7) and the desired double-sided pressure-sensitive adhesive It can be appropriately selected according to the tape layer (8) and the like. The thickness of each of the pressure-sensitive adhesive layers (6a, 7a) can be selected, for example, from the range of 30 to 100 μm (preferably 50 to 80 μm). The thickness of the first pressure-sensitive adhesive layer (6a) and the thickness of the second pressure-sensitive adhesive layer (7a)
They may be the same or different.

The pressure-sensitive adhesive (6, 7) may contain various additives such as a cross-linking agent, a tackifier, a plasticizer, a filler, and an antioxidant, if necessary.

As the drying oven (15) for the double-sided pressure-sensitive adhesive tape used for drying the substrate (5) for the double-sided pressure-sensitive adhesive tape coated with the pressure-sensitive adhesive (6, 7), a known drying oven can be used. . The temperature of the drying oven (15) for double-sided pressure-sensitive adhesive tape can be appropriately selected according to the type of the pressure-sensitive adhesive (6, 7).

When the pressure-sensitive adhesive is a hot-melt type pressure-sensitive adhesive, the drying oven (15) for double-sided pressure-sensitive adhesive tape can be omitted. Further, when the adhesive is polymerized or cross-linked by irradiation with ultraviolet rays or electron beams, the system can be changed to an ultraviolet irradiation system or an electron beam irradiation system corresponding to each.

(Step C) In step C, a double-sided pressure-sensitive adhesive tape (9) having a layer structure as shown in FIG. 4 is produced. In the step C, the surface of the release liner (4) on the side of the first release agent layer (2a) and the surface of the double-sided pressure-sensitive adhesive tape layer (8) on the side of the first pressure-sensitive adhesive layer (6a) are bonded by a laminating machine ( 16). As shown in FIG. 1, the double-sided pressure-sensitive adhesive tape (9) obtained by this lamination can be wound into a roll. When wound up in a roll like this, the surface on the side of the second pressure-sensitive adhesive layer (7a) which is the open surface of the double-sided pressure-sensitive adhesive tape (9) (the surface of the exposed pressure-sensitive adhesive layer) is the second release agent. It overlaps with the surface on the layer (3a) side (the exposed surface of the release agent layer). Therefore, it can be stored or stored in a rolled state, the second pressure-sensitive adhesive layer (7a) can be peeled off from the second release agent layer (3a), and the double-sided pressure-sensitive adhesive tape (9) can be used.

The double-sided pressure-sensitive adhesive tape (9) according to FIG.
As shown in FIG. 4, the release liner 4 is formed on one side of the double-sided pressure-sensitive adhesive tape, but the release liner 4 may be formed on both sides of the double-sided pressure-sensitive adhesive tape layer. Also,
The method of the present invention can also be applied to a case where a release liner having a release agent layer formed only on one side or an adhesive tape layer having an adhesive layer formed only on one side is used.

For example, there are two steps for preparing a release liner by forming a release agent layer on one side of a release liner substrate,
Forming a pressure-sensitive adhesive layer on both surfaces of the double-sided pressure-sensitive adhesive tape substrate to form a double-sided pressure-sensitive adhesive tape layer, and bonding the two release liners to another surface of the double-sided pressure-sensitive adhesive tape layer, A production method in which the step of producing the pressure-sensitive adhesive tape and the step of producing the pressure-sensitive adhesive tape are simultaneously performed in-line.

In the method for producing a double-sided pressure-sensitive adhesive tape of the present invention,
Since step A, step B, and step C are combined, a double-sided pressure-sensitive adhesive tape can be easily and efficiently manufactured with excellent workability. In addition, since the method includes the specific steps, it can be manufactured at low cost. In particular,
Since the double-sided pressure-sensitive adhesive tape produced by the method of the present invention is bonded to the double-sided pressure-sensitive adhesive tape layer as soon as the release liner is produced, the release force between the release liner and the double-sided pressure-sensitive adhesive tape layer is constant or almost constant. And the quality is stable. Therefore, it is extremely useful as a method for producing a double-sided pressure-sensitive adhesive tape.

[0038]

Embodiments of the present invention will be described below. Example 1 A double-sided pressure-sensitive adhesive tape was produced by the method shown in FIG. Specifically, high-quality paper having polyethylene (thickness: 25 μm) laminated on both sides is used as a base material for a release liner, and a heavy-release addition-reaction-type thermosetting silicone-based release agent ( Made by Shin-Etsu Chemical Co., Ltd .;
3504 "; Shin-Etsu Chemical Co., Ltd." PL-
50T ") and a light release addition-reaction type thermosetting silicone release agent (Shin-Etsu Chemical Co., Ltd .; product number" KS-835 ") as a second release agent; Shin-Etsu Chemical Co., Ltd. as a curing catalyst Using "PL-50T"), the first release agent layer and the second release agent layer were formed on different surfaces of the release liner substrate, respectively, to produce a release liner. In parallel with the production of the release liner, a polyester film (thickness: 50 μm) was used as a base material for a double-sided pressure-sensitive adhesive tape, and an acrylic pressure-sensitive adhesive (acrylic acid) was used as a first pressure-sensitive adhesive and a second pressure-sensitive adhesive. Butyl: acrylic acid = 100: 8 (parts by weight) copolymer) to form a first pressure-sensitive adhesive layer and a second pressure-sensitive adhesive layer on different surfaces of a base material for a double-sided pressure-sensitive adhesive tape. To prepare a double-sided pressure-sensitive adhesive tape layer. That is, a release liner and a double-sided pressure-sensitive adhesive tape layer were simultaneously prepared in-line and in parallel. The release liner and the double-sided pressure-sensitive adhesive tape layer produced simultaneously in-line are further attached and in-line simultaneously with the production, and wound into a roll to form a double-sided pressure-sensitive adhesive tape (hereinafter sometimes referred to as “sample 1”). ) Was prepared. That is, the release liner, the double-sided pressure-sensitive adhesive tape layer, and the double-sided pressure-sensitive adhesive tape are manufactured in-line, simultaneously in parallel, and continuously.

COMPARATIVE EXAMPLE 1 A release liner (sometimes referred to as an “off-line release liner”) was prepared in the same manner as the method for preparing the release liner in Example 1, and the off-line release liner was used for 30 days a day. Stored for days. The day or 30
Double-sided adhesive using a release liner stored for 1 day in the same manner as in Example 1 except that an off-line release liner stored for one day is used (that is, the step of applying a release agent to a release liner substrate is not performed). A tape (sometimes referred to as “sample 2”) and a double-sided adhesive tape using a release liner stored for 30 days (sometimes referred to as “sample 3”) were produced.

Evaluation With respect to the double-sided pressure-sensitive adhesive tapes (samples 1 to 3) obtained in Example 1 and Comparative Example 1, the peeling force of the release liner to the double-sided pressure-sensitive adhesive tape layer was measured by the following peeling force measuring method, and the peeling properties were measured. Was evaluated. Table 1 shows the evaluation results.
It was shown to. Peeling force measuring method After aging samples 1 to 3 at 50 ° C. for 1 day, 2
After adjusting for 4 hours in an atmosphere of 3 ° C. × 65% RH, the release liner was pulled and peeled at a speed of 300 mm / min by a tensile tester, and the peeling force was measured. The release force includes a release force between the surface of the release liner on the side of the first release agent (heavy release agent) layer and the pressure-sensitive adhesive layer, and a second release agent (light release agent) of the release liner. The peeling force between the layer-side surface and the pressure-sensitive adhesive layer was measured a plurality of times. In addition, the fluctuation | variation width | variety of the peeling force was also calculated | required about the release agent layer of heavy peelability.

[0041]

[Table 1]

Evaluation Results From Table 1, it was confirmed that the double-sided pressure-sensitive adhesive tape according to Example 1 had a small change in the peeling force and a stable peeling force. In particular, even if the release agent of the release liner is a heavy release release agent, the release force is stable with little fluctuation. This is because, in the double-sided pressure-sensitive adhesive tape according to Example 1, the production step of the release liner, the production step of the double-sided pressure-sensitive adhesive tape layer, and the bonding step of these are simultaneously performed in-line, and the storage of the release liner occurs. It seems that it is not.

[0043]

According to the method for producing a double-sided pressure-sensitive adhesive tape of the present invention, the release property of the release agent layer in the release liner is stable and the double-sided pressure-sensitive adhesive tape can exhibit a constant release property. Can be easily obtained. In particular, since the production method of the present invention has specific steps combined,
Excellent workability. Moreover, the double-sided pressure-sensitive adhesive tape can be manufactured continuously at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating a method for producing a double-sided pressure-sensitive adhesive tape of the present invention.

FIG. 2 is a schematic sectional view showing a release liner in the manufacturing method of FIG.

FIG. 3 is a schematic sectional view showing a double-sided pressure-sensitive adhesive tape layer in the production method of FIG.

FIG. 4 is a schematic sectional view showing a double-sided pressure-sensitive adhesive tape in the manufacturing method of FIG.

FIG. 5 is a schematic view showing an example of an intermediate portion in a conventional method for producing a double-sided pressure-sensitive adhesive tape.

FIG. 6 is a schematic view showing a continuous example of the manufacturing method of FIG. 5;

FIG. 7 is a schematic view showing another example continued from the manufacturing method of FIG. 5;

FIG. 8 is a schematic view showing still another example of the conventional method for producing a double-sided pressure-sensitive adhesive tape.

[Explanation of symbols]

 Reference Signs List 1 base material for release liner 2 release agent (first release agent) 3 release agent (second release agent) 4 release liner 5 base material for double-sided adhesive tape 6 adhesive (first adhesive) 7 adhesive (second adhesive) 8) Double-sided adhesive tape layer 9 Double-sided adhesive tape

Continued on the front page (72) Inventor Tomokazu Himura 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 4J004 AB01 DB02 EA05 GA01 GA02

Claims (1)

[Claims] 1. A step A of forming a release liner by forming release agent layers on both sides of a release liner substrate, and forming an adhesive layer on both sides of a double-sided pressure-sensitive adhesive tape substrate to form a double-sided pressure-sensitive adhesive tape layer. A method for producing a double-sided pressure-sensitive adhesive tape, wherein a step B of preparing and a step C of bonding the release liner and the double-sided pressure-sensitive adhesive tape layer to prepare a double-sided pressure-sensitive adhesive tape are simultaneously performed in-line.