JP2003147295A - Adhesion member and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesion member by using a non-silicone releasing agent manifesting light release force in a low speed to high-speed regions of releasing speed. SOLUTION: The method for producing the adhesion member comprises laminating a release layer (1) comprising a linear ethylene based resin having 3-30 wt.% of a resin fraction eluted at 30 deg.C by the temperature-ascending elution fractionation method, to a base (2) supporting an adhesion layer (3), and then subjecting the laminate to a heat aging in an atmosphere of 55-75 deg.C for >=6 hr, and controlling the adhesion layer with the supporting base to manifest releasing force of 0.5-5 N/50 mm in 180 deg. peeling of the adhesive layer together with the supporting base at a speed of 2 m/min.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive member suitable for the field of precision electronics where the use of a silicone component such as a silicone-based release agent is inappropriate, and a method for producing the same.

[0002]

2. Description of the Related Art Adhesive members such as adhesive tapes and labels are widely used in the field of precision electronics. The form of such an adhesive member is such that an adhesive layer is provided on one surface of a base material and a release layer is provided on the other surface to form a wound tape, or an adhesive layer provided on a base material is a release liner via a release layer. The form such as a label covered with is common. As the release layer, when a silicone-based release agent is used, there is a risk of secondary contamination with silicone, so a non-silicone-based release agent is used.

Conventionally, as the above-mentioned non-silicone-based release agent, one comprising a polyolefin elastomer such as ethylene / α-olefin or a mixture thereof with polyethylene or other thermoplastic resin has been known (JP-A-55-55). No. 65281, JP-A-55-804.
79, JP-A-6-155687). These are release agents using low-density polyethylene alone (Japanese Patent Publication No.
No. 20205 gazette), the force required for peeling is large (heavy peeling), the peeling performance is low, and adhesive residue is generated.

However, the improvement effect is insufficient,
At a peeling speed in the low speed region of 0.5 m / min or less, although the force required for peeling is sufficiently small and light peeling is achieved,
At a peeling speed in a high-speed region of 1 m / min or more, heavy peeling occurs, and smooth peeling becomes difficult. The problem that heavy peeling or smooth peeling becomes difficult is that it cannot be peeled off at a practical peeling speed, it becomes difficult to peel off, or wrinkles etc. occur on the adhesive member due to interruption of smooth peeling,
This is a cause of inconvenience such as a large peeling noise and noise.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain an adhesive member using a non-silicone release agent which achieves light release at a release rate from a low speed region to a high speed region.

[0006]

According to the present invention, the amount of eluted components at 30 ° C. or lower measured by the temperature rising elution fractionation method is 3% by weight to
After the release layer made of 30% by weight of the linear ethylene resin and the adhesive layer supported by the base material are adhered, 55 to 7
When the pressure-sensitive adhesive layer is peeled together with the supporting base material at a speed of 2 m / min for 180 degrees by aging under an atmosphere of 5 ° C. for 6 hours or more, the force required for the peeling is 0.5 to 5 N.
The present invention provides a method for manufacturing an adhesive member, which is characterized in that the pressure is controlled to / 50 mm.

[0007]

EFFECTS OF THE INVENTION According to the present invention, it is possible to obtain an adhesive member using a non-silicone release agent that can achieve light release at a release rate from a low speed region to a high speed region. As described above, the polyethylene-based peeling layer has a large peeling speed dependency and causes heavy peeling in the high-speed peeling region, which could not be avoided until now, but is aged under the specific temperature atmosphere described above. It was unexpected that the operation achieved a light release in the high speed release area.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The production method according to the present invention comprises a release layer made of a linear ethylene resin having an elution component content of 3% by weight to 30% by weight at 30 ° C. or less measured by a temperature rising elution fractionation method. And the pressure-sensitive adhesive layer supported by the base material, and then aged for 6 hours or more in an atmosphere of 55 to 75 ° C. to peel the pressure-sensitive adhesive layer together with the support base material at a speed of 2 m / min for 180 degrees. In this case, the pressure-sensitive adhesive member whose peeling force is controlled to 0.5 to 5 N / 50 mm is obtained.

An example of the above-mentioned adhesive member is shown in FIGS. FIG. 1 shows a form representative of a case where a peeling layer and an adhesive layer are integrally provided via a base material and used as an adhesive tape or the like. This has a release layer 1 made of the linear ethylene resin on one side of a base material 2 and an adhesive layer 3 on the other side of the base material 2. Usually, the adhesive layer 3 is used by adhering it to the peeling layer 2 on its back surface to form a wound body. Therefore, in this case, the aging treatment described above can be performed in the form of a wound body.

On the other hand, FIG. 2 has a release layer 1 made of the linear ethylene resin on the surface of a substrate 6, and an adhesive layer 5 on another substrate 4 on the release layer. 1 shows an example of an adhesive member having a form in which an adhesive sheet is adhered via its adhesive layer. The form in which the release layer and the pressure-sensitive adhesive layer can be separated separately is typical when the pressure-sensitive adhesive sheet (4, 5) used as a label substrate or label is supported by the release liner (1, 6). It is a form that is done. Therefore, in this case, the aging treatment described above can be performed with the adhesive layer adhered to the release layer.

The adhesive member is not limited to the above example,
The adhesive layer may be provided not only on one side of the substrate but also on both sides. In that case, a wound body or the like that can be easily rewound can be obtained by using a separator or a release liner having a release layer made of the linear ethylene resin on both sides. Therefore, the pressure-sensitive adhesive member can be formed as having a form similar to the conventional pressure-sensitive adhesive member represented by a pressure-sensitive adhesive tape, a double-sided pressure-sensitive adhesive tape, a surface protective sheet, a label sheet and the like.

The release layer is a temperature rising elution fractionation method (TREF) for the purpose of achieving silicone-free property.
ng E1ution Fractionation method), the amount of eluted components at 30 ° C or lower is 3% by weight to 3% of the whole resin material.
It is formed of a linear ethylene resin of 0% by weight, preferably 20% by weight or less, particularly preferably 4% by weight to 15% by weight. When the amount of the eluted component is less than 3% by weight, the peeling performance is poor and the object cannot be achieved. When it exceeds 30% by weight, the shape is too soft to maintain the shape and the heat resistance is also poor.

The temperature rising elution fractionation method can be carried out, for example, by the following method. That is, a linear ethylene resin is dissolved in o-dichlorobenzene at a temperature at which it is completely dissolved, by the way, dissolved in it at 140 ° C., and cooled to −10 ° C. at a constant rate and 1 ° C./min. To form a thin polymer layer in a TREF column packed with glass beads. At that time, a polymer layer of a highly crystalline component which is easily crystallized is formed, and then a polymer layer of a low crystalline or amorphous component which is hard to be crystallized is formed.

After that, the temperature is maintained at -10 ° C. for 60 minutes, and the temperature is raised stepwise while flowing o-dichlorobenzene as a mobile phase in the column at a flow rate of 1 m 1 / min. Then, contrary to the above, the low crystalline or amorphous component elutes first, and then the high crystalline component elutes. Thus, the composition distribution of the resin material is analyzed from the elution curve drawn by the elution amount and the elution temperature of the components sequentially eluted at each temperature.
In addition, such an operation is performed by, for example, a cross fractionation chromatograph apparatus (manufactured by Mitsubishi Chemical (formerly Mitsubishi Yuka), CFC T-150).
This can be realized by using a device for performing a known temperature rising elution fractionation method such as A type).

As the linear ethylene resin, for example, a linear ethylene resin, a mixture containing a linear ethylene resin as a main component and other resin components or additives, and an α-olefin having 3 to 12 carbon atoms. One or two or more linear polymers containing an ethylene component in an amount of 50% by weight or more, especially 60% by weight or more, and particularly 70% by weight or more, such as a copolymer of ethylene and ethylene can be used. Those satisfying the above-mentioned conditions for the amount of the eluted component can be obtained by appropriately selecting, for example, copolymerization conditions, purification conditions and / or fractionation conditions by a known method, or can be obtained as a commercial product.

The α-olefin forming the above-mentioned copolymer with ethylene is not particularly limited. Incidentally, examples thereof include α-olefins having 3 to 12 carbon atoms such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene. The copolymer may be one or two or more kinds of α-olefin having 3 to 12 carbon atoms. Above all, ethylene / 1
-Butene copolymer, ethylene-4-methyl-1-pentene copolymer, ethylene / 1-hexene copolymer and ethylene / 1-octene copolymer are preferred.

By using the linear ethylene resin as described above, compared with the conventional method using a mixed resin of low density polyethylene and an ethylene / propylene copolymer or an ethylene / 1-butene random copolymer. However, there is an advantage that the release layer forming material can be prepared in a small number of steps, and the release layer having an excellent release function can be formed more easily and efficiently.

The above-mentioned release layer has excellent release performance and has a release function suitable for adhesive tapes and labels.
Even when the pressure-sensitive adhesive layer has high adhesive strength, the peeling performance is excellent, and the pressure-sensitive adhesive does not easily adhere to the peeling layer during peeling, or inconvenient peeling such as stick slip is unlikely to occur. Therefore, it also has an advantage that the surface roughness of the adhesive layer exposed through peeling can be appropriately maintained.

As the other resin component which may be mixed with the above-mentioned linear ethylene resin, other kinds of polyethylene, homopolymers of the above α-olefins, and two or more kinds of α-olefins are used. Examples thereof include copolymers, and one or more of them can be blended. The amount of such a resin component or additive compounded is within a range that does not impair the peeling function, film formability, solvent resistance and heat resistance based on the linear ethylene resin.

The release layer can be obtained as a film having a thickness of 20 to 500 μm and also used as a substrate, but generally, for the purpose of improving rigidity and strength, it is supported by a substrate as shown in the figure. To be done. In the case of the above-mentioned integral type adhesive tape or the separate type release liner or separator, the form in which the release layer is supported by the substrate is preferable.

The release layer supported by the base material is formed, for example, by applying a solution or melt to the base material to form a film, by fusing the film into the base material, It can be performed by an appropriate method such as a method of forming a laminate film by a coextrusion molding method or the like together with the plastic forming the film. In that case, the thickness of the release layer is not particularly limited and can be appropriately determined. Generally, the thickness is 1 to 100 μm, preferably 5 to 50 μm, and particularly 10 to 40 μm in view of stable formability of the release layer and thinning.

As the base material for supporting the release layer and the adhesive layer,
Appropriate thin sheets such as films and sheets made of various plastics, paper and cloth, non-woven fabrics and metal foils, nets and foams, and laminates thereof can be used, and any of the conventional base materials for adhesive members can be used. sell. The base material is
It may be one having a conductor layer or a magnetic layer, and / or containing a conductive powder or a magnetic powder and capable of induction heating via a high frequency.

In applications such as precision electronics where the participation of silicone is unsuitable, paper powder is often unsuitable, so that the base material preferably used in such applications is polyester, polyamide, polypropylene or high-quality materials. Films made of various plastics such as density polyethylene and polyimide are preferably used. The thickness of the base material can be appropriately determined, but is generally 500 μm or less, especially 5 to 300 μm.
m, especially 10 to 250 μm.

As shown in FIG. 2, when the pressure-sensitive adhesive sheet and the release liner are used as separate type pressure-sensitive adhesive members, the base material of the pressure-sensitive adhesive sheet and the base material of the release liner are:
They may be of the same type or of different types. When the adhesive sheet is a label base material, it is preferably a base material on which ink information can be fixed by a thermal transfer method.

As the above-mentioned ink-fixing base material, an appropriate base material according to a conventional label such as the above-mentioned plastic film or paper may be used. According to the thermal transfer system, there is an advantage that necessary ink information can be printed at any time while changing the content in the field and the label can be issued on occasion. It should be noted that the surface of the base material on which the release layer or adhesive layer is provided will have improved adhesion, such as anchor coating, corona discharge treatment, chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. An appropriate surface treatment can be applied for the purpose of

When the base material supporting the release layer is formed of polypropylene, a method of co-extruding the release layer forming material and polypropylene to obtain a laminated film is
It is more preferable in terms of adhesion between the release layer and the base material, production efficiency, and the like. In that case, the thickness of the polypropylene film layer is
30 to 120 μm is preferable for a release layer having a thickness of 5 to 50 μm.

For forming the adhesive layer in the adhesive member, for example, various kinds of suitable polymers such as rubber-based, acrylic-based, vinyl alkyl ether-based, polyester-based, polyamide-based, urethane-based and the like are used as a base polymer. Adhesives of can be used. Therefore, a pressure sensitive adhesive such as an ultraviolet curable type, a hot melt type or a pressure sensitive type at the time of heat can be used. The pressure-sensitive adhesive may be a mixture of appropriate additives such as a cross-linking agent, a tackifier, a plasticizer, a filler, and an anti-aging agent, if necessary.

In particular, from the viewpoints of avoidance of silicone component and peeling performance, it is composed of an ester such as acrylic acid or methacrylic acid having an alkyl group having 20 or less carbon atoms (meth).
By using one or more kinds of acrylic acid-based alkyl esters, one or more kinds of other monomers suitable for the purpose of adjusting bulk properties such as cohesive strength, heat resistance and crosslinkability, etc. may be used as needed. An acrylic pressure-sensitive adhesive containing a polymerized acrylic polymer as a base polymer can be preferably used.

The pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive on a substrate by an appropriate method such as a doctor blade method or a gravure printing method, or by using a pressure-sensitive adhesive layer formed on a separator or the like. It can be performed by an appropriate method such as a method of transferring onto a material. The thickness of the pressure-sensitive adhesive layer may be appropriately determined depending on the purpose of use, but is generally 500 μm or less, preferably 1 to 300 μm, and particularly 5 to 100 μm.
The adhesive layer may be subjected to an appropriate treatment such as crosslinking treatment by electron beam irradiation for the purpose of adjusting bulk properties.

The pressure-sensitive adhesive member according to the present invention has a pressure-sensitive adhesive layer adhered to a release layer together with its supporting substrate at a speed of 2 m / min.
The force required for peeling when peeled at 0 degrees (peeling force)
Is controlled to 0.5 to 5 N / 50 mm. Achievement of such a peeling force can be performed, for example, by aging the peeling layer and the pressure-sensitive adhesive layer in an adhered state under an atmosphere of 55 to 75 ° C. for 6 hours or more.

If the aging temperature is less than 55 ° C., light peeling cannot be achieved in the high speed peeling region. On the other hand, when the temperature exceeds 75 ° C., heavy peeling progresses. The effect of aging is
It begins to appear about 1 hour after the start of aging, and reaches a satisfactory state within 6 hours. From the viewpoint of achieving a stable effect, the preferred aging time is 10 hours or more, especially 15
It is more than 20 hours, especially more than 20 hours. The upper limit of the aging time is not particularly limited, but is preferably 120 hours or less from the viewpoint of production efficiency and the like.

Therefore, the above-mentioned aging treatment is different from the conventional treatment which may be carried out for the purpose of accelerating the cross-linking of the pressure-sensitive adhesive layer and stabilizing the adhesion state with the peeling layer, and is different from the conventional treatment in temperature range. Is. That is, the conventional treatment does not achieve the light peeling in the high-speed peeling region, which is the object of the present invention.

The adhesive member according to the present invention is used for various purposes such as a label, a sticker, a sticker, a patch, a slip, a bulletin board, a wrapping tape, a surface protective material, an adhesive tape, etc., for commercial use, industrial use, agricultural use and medical use. , It can be used in various fields such as optical use, office use, and household use. In particular, from the standpoint of achieving silicone-free property, it can be advantageously used in fields such as precision electronic fields where the participation of silicone components is not preferable.

[0034]

EXAMPLES Example 1 Ethylene / 1-hexene copolymer which is a linear ethylene resin (manufactured by Nippon Polyolefin Co., Ltd., J-LEX LLA
C41SA) and polypropylene (manufactured by Japan Polychem,
FY-4) is coextruded at 230 ° C. to give a thickness of 30.
A release liner comprising a laminate of a μm release layer and a 80 μm thick polypropylene layer was obtained. The result of applying the temperature rising elution fractionation method using a cross fractionation chromatograph (CFC T-150A type) (the same applies hereinafter), 30 ° C.
The amount of eluted components in the whole linear ethylene resin below was 7.8% by weight.

On the other hand, on a corona-treated surface of a white polyester film (W400C manufactured by Mitsubishi Chemical Co., Ltd.) having a thickness of 50 μm,
A 30 μm thick acrylic pressure-sensitive adhesive layer is formed, and the pressure-sensitive adhesive layer is adhered to the release layer of the release liner at 55 ° C. and 48
Aging treatment for time was carried out to obtain an adhesive member for label formation.

Example 2 An ethylene / 1-octene copolymer (Idemitsu Petrochemical Co., Ltd., Moretec 0218CN), which is a linear ethylene resin having an elution component amount of 4.8% by weight at 30 ° C. or lower, was added to 5
A release liner in which a 20 μm-thick release layer is laminated is obtained by extrusion coating at 250 ° C. on a 0 μm-thick polyester film through an undercoat layer.
An adhesive member was obtained in the same manner as in Example 1 except that the aging treatment was performed at 0 ° C for 48 hours.

Example 3 Ethylene-1 containing 20% by weight of low-density polyethylene
-A linear ethylene resin (Idemitsu Petrochemical Co., Ltd., Moretec 1018D) consisting of an octene copolymer and having an elution component amount of 5.4% by weight at 30 ° C or lower was used at 65 ° C.
An adhesive member was obtained in the same manner as in Example 2 except that the aging treatment was performed for 48 hours.

Comparative Example 1 An adhesive member was obtained in the same manner as in Example 1 except that the aging conditions were 40 ° C. and 48 hours.

Comparative Example 2 An ethylene / 1-hexene copolymer (Evolution SP1540 manufactured by Mitsui Chemicals, Inc.) having a dissolution amount of 1.0% by weight at 30 ° C. or lower was used as the linear ethylene resin. An adhesive member was obtained in the same manner as in Example 1.

Evaluation test Six samples each having a width of 50 cut from the pressure-sensitive adhesive members obtained in Examples and Comparative Examples were prepared, and the release liner side of each sample was adhesively fixed to a plate-like body having rigidity. Universal tensile tester on the sheet side (ORIENTEC, RTM-10
At 0), under a 23 ° C., 60% RH atmosphere, pulling is performed under the conditions of a crosshead speed of 0.3 m / min (low-speed peeling) or 2.0 m / min (high-speed peeling), and a peeling test is performed by 180 degree peel The peeling force was measured and the average value of the test results of three times was calculated.

The above results are shown in the following table. Exfoliation force implementation example comparisons example (N / 50mm) 1 2 3 1 2 low speed 0.3 0.4 0.3 0.4 0.4 High-speed time 1.5 3.2 2.1 11.8 8.6

As can be seen from the table, in the low-speed peeling, the comparative examples also showed light peeling similarly to the examples. However, in the high-speed peeling, the examples maintain good light peeling property, whereas the comparative examples show heavy peeling. It is understood that there is.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment.

FIG. 2 is a sectional view of another embodiment.

[Explanation of symbols]

1: Release layer 2, 4, 6: Base material 3, 5: Adhesive layer

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J004 AA02 AA05 AA10 AA14 AA15                       AA16 CA03 CA04 CA06 CC03                       DA02 DB01 FA01 FA08 GA01                 4J040 CA001 DA051 DD051 DF001                       DF041 ED001 EG001 LA07                       NA01 NA02 NA05 NA06 NA17                       NA20 NA21

Claims (8)

[Claims] 1. 30 measured by temperature rising elution fractionation method
After the release layer made of a linear ethylene resin having an elution component amount of 3% by weight to 30% by weight at a temperature of ℃ or less and the pressure-sensitive adhesive layer supported by the base material are adhered, under an atmosphere of 55 to 75 ° C. When aged for 6 hours or more and peeling the adhesive layer together with the supporting substrate at a speed of 2 m / min for 180 degrees, the force required for the peeling is controlled to 0.5 to 5 N / 50 mm. A method of manufacturing an adhesive member. 2. A temperature rising elution fractionation method for measuring 30
3% by weight of the total amount of resin material at the temperature below ℃
A release layer comprising 30% by weight of a linear ethylene resin is provided on one side of the substrate, and an adhesive layer is provided on the other side of the substrate. The adhesive layer is adhered to the release layer. A pressure-sensitive adhesive member, wherein the force required for peeling when peeled 180 degrees at a speed of 2 m / min is 0.5 to 5 N / 50 mm. 3. A straight-chain ethylene-based resin having an amount of elution components at 30 ° C. or less, measured by a temperature rising elution fractionation method, of 3% by weight to 30% by weight of the entire resin material, on the surface of a base material. A pressure-sensitive adhesive sheet having a release layer, and having a pressure-sensitive adhesive layer on another base material is adhered onto the release layer via the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive sheet was peeled 180 degrees at a speed of 2 m / min. In that case, the force required for the peeling is 0.5 to 5 N /
An adhesive member characterized by being 50 mm. 4. The adhesive member according to claim 3, wherein the adhesive sheet is a label base material or a label. 5. The adhesive member according to claim 4, wherein the label base material has a base material on which ink information can be fixed by a thermal transfer method. 6. The pressure-sensitive adhesive member according to claim 2, wherein the linear ethylene resin forming the release layer is a copolymer of an α-olefin having 3 to 12 carbon atoms and ethylene. 7. The adhesive member according to claim 2, wherein the adhesive layer is made of an acrylic adhesive. 8. The release layer according to claim 2, wherein the release layer has a thickness of 5 to 50 μm, and the base material supporting the release layer has a thickness of 30 to 12.
An adhesive member made of a polypropylene film of 0 μm, and its release layer and a base material made of a laminate by coextrusion molding.