JPH09157610A - Surface-protecting adhesive film and dustproof adhesive mat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a surface-protecting adhesive film and a dustproof adhesive sufficient in adhesive property and having both improved antistatic and dustproof functions. SOLUTION: A substrate 1 consisting of a polyolefin monolayer film containing >=10% composition prepared by compounding at least two kinds of ionomers which have been neutralized with alkali metals including potassium, or a multilayer film prepared by extruding a polyolefin containing the ionomer composition together with a polyolefin free from the composition is prepared. A hardening reaction-type acrylic adhesive 2 is applied on the substrate 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive film for surface protection which is excellent in antistatic performance and an adhesive mat for dust removal.

[0002]

2. Description of the Related Art Conventionally, a film attached to the surface of an electronic device or the like to protect it, or a laminated mat to be placed on a floor or the like to remove dust or dirt from people or objects when passing by, A tacky polyolefin film is used.

[0003] In use, when the film is unwound or peeled off, a peeling charge is generated on the film, and the static electricity causes foreign matter around the film to adhere to the film, or the used film is not used. The operator feels a great deal of discomfort due to the wrapping around his hands or the impact of static electricity sparks.

Further, static electricity generated when the surface protective film is peeled off from an electronic device after use may cause electrostatic breakdown of the electronic device, or a new laminated mat from which a contaminated film for dust removal is removed is charged. Then, static electricity remains, and when the static electricity is transferred to people or objects passing through this surface, and these people or objects come into contact with the precision electronic equipment, a large trouble occurs with respect to the precision electronic equipment. There was something to do.

Therefore, as a measure for preventing these troubles, an adhesive is applied to a polyolefin film to which a surfactant-based antistatic agent is added, or an antistatic agent is added to the adhesive applied to the polyolefin film. I was responding by doing.

However, when the film containing the antistatic agent (Comparative Example 3) was used, this was transferred to the adhesive to lower the tack of the adhesive, and Table 2 showing the physical properties of Comparative Example.
As shown in, the performance is not sufficiently exhibited in terms of antistatic.

Also, when a film obtained by adding an antistatic agent to a pressure-sensitive adhesive (Comparative Example 2) is used, similar to Comparative Example 3 described above, not only is it unable to exhibit sufficient antistatic performance, but it is generally used for this purpose. In the case of the isocyanate-curable acrylic pressure-sensitive adhesive used, not only does the antistatic agent lower the pressure-sensitive adhesive performance, but also the adhesion of the pressure-sensitive adhesive to the substrate and the cohesive force become insufficient. And other various problems.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a composition obtained by mixing at least two ionomers neutralized with an alkali metal containing potassium. By using a polyolefin monolayer containing 10% or more or a coextruded multilayer film with an additive-free polyolefin as a substrate, and applying a curing reaction type acrylic adhesive to the substrate, sufficient adhesive properties, antistatic function and dust removal are obtained. It is an object to provide an adhesive film for surface protection and an adhesive mat for dust removal, which can improve both functions.

[0009]

Means for Solving the Problems The means of the present invention for achieving the above-mentioned object is that the constitution of the first example of the surface protective adhesive film is partially or wholly neutralized with an alkali metal containing potassium. The above-mentioned ionomer is mixed with two or more kinds, and it is composed of a polyolefin single-layer base film containing 10% or more of a composition, and a curing reaction type acrylic pressure-sensitive adhesive coated on one side of the base film. .

The structure of the second example is a polyolefin single layer containing 10% or more of a composition obtained by mixing two or more kinds of ionomers partially or wholly neutralized with an alkali metal containing potassium. It comprises a multilayer base film formed by coextrusion of two to three layers consisting of two types of the above-mentioned ionomer-free polyolefin layer, and a curing reaction type acrylic pressure-sensitive adhesive coated on one side of this base film. .

The multilayer base film has a thickness ratio of 1: 4 to 1: 1 and a total thickness of 35 to 120.
It is in the range of μ.

Further, the composition of the dust-removing pressure-sensitive adhesive mat comprises a composition obtained by mixing two or more ionomers partially or wholly neutralized with an alkali metal containing potassium.
% Or more of a single-layer polyolefin base film, or a multi-layered base film of 2 to 3 layers obtained by coextrusion of the polyolefin single layer and the ionomer-free polyolefin, and one of the base films. A large number of surface-protecting pressure-sensitive adhesive films provided with the curing reaction type acrylic pressure-sensitive adhesive coated on the side surface are laminated.

[0013]

The present invention configured as described above has the following effects.

One side of a base film of a polyolefin single layer containing 10% or more of a composition obtained by mixing two or more ionomers partially or wholly neutralized with an alkali metal containing potassium is subjected to a curing reaction. A surface protection adhesive film is formed by applying a mold acrylic adhesive.

In this film, a layer of polyethylene mixed with an ionomer neutralized with an alkali metal is formed immediately below the pressure-sensitive adhesive coating layer to prevent the film from being charged and to prevent the pressure-sensitive adhesive layer from adhering to the film. Does not cause deterioration of sex.

[0016]

EXAMPLES Next, one example of the embodiments of the surface protection adhesive film and the dust removing adhesive mat according to the present invention will be described with reference to the drawings.

1 to 3 and 4, A is an adhesive film for surface protection, which comprises a base film 1 and an adhesive 2.

The first example of the surface-protective pressure-sensitive adhesive film A is a mixture of two or more ionomers partially or wholly neutralized with an alkali metal containing potassium as shown in FIG. A curing reaction type acrylic pressure-sensitive adhesive 2 is applied to one side surface of a single-layer polyolefin base film 1 containing 10% or more of the composition.

When the content of the neutralized ionomer is 10% or less, the surface specific resistance value increases, and the surface specific resistance is almost the same as when the antistatic agent is mixed in the general polyolefin as the base material. Content rate is 1
It is 0% or more, preferably 20% or more.

Further, the above-mentioned surface protective adhesive film A
2 and 3, as shown in FIGS. 2 and 3, 10% of a composition obtained by mixing two or more ionomers partially or wholly neutralized with an alkali metal containing potassium.
On one side of the multilayer base film 1 formed by coextrusion of two or three layers of the polyolefin monolayer 1a containing the above and the polyolefin layer 1b or 1c not containing the ionomer, a curing reaction type acrylic adhesive. Agent 2 has been applied.

Of these, when the base film 1 is composed of two layers, as shown in FIG. 2, a polyolefin single layer 1a mixed with a potassium-neutralized ionomer and a general polyolefin layer 1b containing no ionomer mixed therein. The co-extrusion multi-layer structure is formed by applying the adhesive 2 to the side of the general polyolefin layer 1b in which the ionomer is not mixed.

When the base film 1 is composed of three layers, as shown in FIG. 3, the ionomer is not mixed between the polyolefin single layers 1a and 1c mixed with the potassium-neutralized ionomer. The pressure-sensitive adhesive 2 is applied to the side of the polyolefin layer 1c in which the ionomer is mixed to form three layers of coextrusion with the general polyolefin layer 1b.

The multilayer base film 1 has a thickness ratio in the range of 1: 4 to 1: 1 and a total thickness of 35 to 35.
It is in the range of 120μ.

The thickness of the base film 1 is often used in the surface protecting adhesive film A of the present invention and the dust removing adhesive mat B described later because of its film strength, it is often broken at 35 μm or less during handling. I can't stand it.

If the thickness is 120 μm or more, the film has a too high stiffness (Young's modulus), so that it becomes unsuitable for the target surface protection adherend, and the laminated adhesive mat becomes thick. However, when a multi-layered adhesive mat is installed on the floor, there is a problem that it gets caught on a foot when the mat is passed.

Therefore, the total thickness of the base film 1 is, for example, 7μ: 28μ when 35μ ... 1: 4,
1: 1 17μ: 17μ 120μ ... 1: 4 24μ: 96μ, 1: 1 60μ: 60μ
The thickness of each layer is set like this.

Of these, the most preferable thickness of the base film 1 is 50 to 60 μm. In this thickness, in the case of a three-layer structure, a ratio of 5μ / 40μ / 5μ or 6μ / 48μ / 6μ is adopted.

Next, the dust-removing pressure-sensitive adhesive mat B in the embodiment of the present invention has a constitution in which a large number of the above-mentioned surface-protecting pressure-sensitive adhesive films A are laminated, as shown in FIGS.
Polyolefin monolayer base film 1 containing 10% or more of a composition obtained by mixing two or more ionomers partially or wholly neutralized with an alkali metal containing potassium
Or, in this polyolefin single-layer substrate film 1, a substrate film 1 comprising multilayers 1b and 1c consisting of 2-3 layers by coextrusion of the polyolefin single layer 1a and the above-mentioned ionomer-free polyolefin, and this substrate As shown in FIG. 4, a surface protection adhesive film A composed of a curing reaction type acrylic adhesive 2 applied to one side of the material film 1 is laminated on a large number, for example, about 10 to 100. There is.

The number of the laminated sheets is appropriate, but if the soiled surface of the sheet is removed each time, the mat B will be formed in a short period of time.
Is consumed, and the total thickness of the mat B becomes too thick when a large number of layers are laminated. Therefore, it is preferably about 20 to 60 layers.

Next, each Example and each Comparative Example according to the present invention will be specifically described with reference to Tables 1 and 2 of the attached table.

(Example 1) Preparation of base film: -Ethylene-methacrylic acid copolymer containing 20 wt% methacrylic acid-Equivalent mixture of ethylene-methacrylic acid copolymer containing 4 wt% methacrylic acid- Ionomer composition neutralized with potassium (1.21 mmol / g resin containing potassium ion, ionization degree 8)
3%) is melt-mixed in 20% and medium density polyethylene (density 0.935, MFR: 1.6, Mitsui DuPont Polychemical Co., Ltd. trade name TR5075-4) is extruded as a single layer, and by an inflation film forming method. A 50μ film was made: One side of this single layer film was corona discharge treated.

Polymerization of acrylic adhesive: 2 ethylhexyl acrylate: 40 wt% butyl acrylate: 40 wt% vinyl acetate: 16 wt% acrylic acid: 3 wt% hydroxyethyl methacrylate: 1 wt% '-azobisisobutyronitrile
Was used as a catalyst to polymerize in ethyl acetate under a nitrogen stream to obtain an acrylic pressure-sensitive adhesive having a degree of polymerization Mw of 700,000 to 800,000 and a solid content of 30%.

Polymerization / Coating / Drying / Laminating of Adhesive: The adhesive obtained in the following formulation was blended, and the solid content was 5 g / m ² on the corona discharge treated side of the monolayer film prepared by the method.
It was coated and dried at 80 ° C. for 5 minutes, and 50 sheets of this film with an adhesive were laminated to obtain an adhesive mat for dust removal.

Acrylic adhesive () 100 wtPHR Coronate L 3 Total (solid content ratio) 103 was formulated.

(Example 2) As a raw material to be used, medium density polyethylene obtained by blending 20% of the potassium-neutralized ionomer used in (Example 1), and low density polyethylene (density: 0.921, MFR:
3.5 Mitsui Petrochemical Co., Ltd. product name Mirason M-
12) is co-extruded, -The film is formed by the inflation method, -The low-density polyethylene side is subjected to corona discharge treatment, -The medium-density polyethylene 20μ / low-density polyethylene 30
A two-layer film with μ was obtained.

On the low density polyethylene side with corona discharge treatment of this two-layer coextrusion film, the same adhesive as in (Example 1) was applied and dried in the same manner as in (Example 1), Fifty sheets were laminated to prepare an adhesive mat for dust removal.

(Example 3) As a raw material to be used, a medium density polyethylene layer obtained by blending 20% of the potassium-neutralized ionomer used in (Example 1) was used on both sides, and as an intermediate layer (in Example 1). Using the low density polyethylene that has been prepared: 5 μ of medium density polyethylene / 40 μ of low density polyethylene
A three-layer coextruded film was obtained by an inflation film formation method with a constitution of 5 μ of medium density polyethylene.

A corona discharge treatment is applied to one side of this film, the same adhesive as in (Example 1) is applied to this, and drying is performed. 50 layers of this film with an adhesive are laminated. Then, an adhesive mat for dust removal was prepared.

In the use of the dust-removing pressure-sensitive adhesive mat in (Examples 1 to 3) described above, as the dust-removing mat, after walking on the pressure-sensitive adhesive surface and adhering dust, the used contaminated surface first layer is pulled. When peeled off, static electricity-generated spark impact and wrapping around the hand due to static electricity could be prevented by the constitution in which the film layer having an antistatic function was in contact with the adhesive (Example 2).

Furthermore, in order to prevent the transfer of the static electricity on the pressure-sensitive adhesive mat, which has a newly unused pressure-sensitive adhesive surface, to the human body, stretcher, etc. passing above it by peeling off the used first layer. As shown in (Example 1) and (Example 3), a polyethylene layer mixed with an ionomer neutralized with an alkali metal having an antistatic effect must be provided immediately below the adhesive coating layer, and However, even if an acrylic adhesive is coated on this antistatic olefin layer, the amount of adhesive is 10
If it is g / m ² or less, the antistatic function is not deteriorated.

Although both (Example 1) and (Example 3) have a polyolefin layer having an antistatic function immediately below the adhesive, a large amount of expensive alkali metal-neutralized ionomer having a resin unit price is used. (Example 1), inexpensive general low density polyethylene was used for the intermediate layer (Example 3)
Has almost the same electrical characteristics on the surface and has sufficient performance with the configuration of (Example 3), and was able to provide equivalent quality at a low price.

(Comparative Example 1) As a raw material to be used, a single-layer film (with corona discharge treatment, 50 μ thickness) formed by inflation method film formation of low density polyethylene (density: 0.921, MFR: 3.5) is used. Except for the above, in the same manner as in (Example 1), a 50-layer laminated dust removal adhesive mat was prepared.

(Comparative Example 2) A pressure-sensitive adhesive containing a conductive agent was added to the raw material used in (Comparative Example 1) by using the polymerized acrylic polymer used in (Example 1) as described below.
The adhesive mat for dust removal was prepared by applying 50 g of the adhesive coated film obtained by applying g / m ² and drying at 80 ° C. for 5 minutes.

Polymerization adhesive of (Example 1) 100 wtPHR Coronate L 3 Antistatic agent 2 Total (solid content ratio) 105 Antistatic agent: Cationic quaternary ammonium type sea surface active agent (Am. Cyanamid: Cyastat LS manufactured by the company) Antistatic Agent
).

(Comparative Example 3) As a raw material to be used, a low density polyethylene (2,500 ppm of an antistatic agent (forioxyethylene alkylamine, for example, Anstex SA-35 manufactured by Toho Chemical Industry Co., Ltd.)) was added ( density:
Dust removal by laminating 50 sheets in the same manner as in the above (Example 1) except that a 50 μ-thick single layer film (with corona discharge treatment) of 0.921, MFR: 3.5) formed by inflation method is used. I made an adhesive mat for.

In the use of the dust-removing mat in these comparative examples, (Comparative Example 1) does not take any measures for preventing static electricity in both the constituent material and the adhesive, and the amount of static electricity generated is extremely large. , Could not be used for this purpose.

In Comparative Example 2, an antistatic agent was added to the pressure-sensitive adhesive to solve the problem of the present invention. However, although the electric characteristics of the pressure-sensitive adhesive surface were slightly improved, it was 2 parts or more. When the antistatic agent was added, the physical properties of the adhesive were reduced by leaching to the surface of the adhesive, and the inhibition of the effect of the adhesive was caused by the reaction with the isocyanate curing agent.

As a matter of course, since the polyethylene film as the base material does not have an antistatic function, the back surface of the adhesive coating does not have an antistatic function.

In Comparative Example 3, polyethylene containing an antistatic agent, which is generally used in conventional polyolefin resins, is used as the base film, and a slight antistatic effect is recognized on the back surface of the dust removing sheet. However, it does not satisfy the electrical characteristics required for this application, and the adhesive coated surface has no antistatic function at all.

[0050]

[Table 1]

[0051]

[Table 2]

The methods for measuring the physical properties shown in the above table are the conventional methods.

[0053]

INDUSTRIAL APPLICABILITY The present invention constructed as described above relates to the use of a surface protection adhesive film used for surface protection of articles and a dust removal adhesive mat for removing dust from people and objects. At the time of unraveling or peeling off, peeling electrification does not cause discomfort due to spark impact, and the film is prevented from being electrified, so electrostatic transfer to other objects due to electrification does not occur. In addition, the static electricity does not adversely affect the precision electronic equipment.

Further, the adhesiveness to the pressure-sensitive adhesive is not deteriorated, and the adhesiveness of the pressure-sensitive adhesive to the base material is not insufficient and the cohesive force is not insufficient. And the like.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing an embodiment of a pressure-sensitive adhesive film for surface protection of the present invention.

FIG. 2 is a cross-sectional view of a main part showing another example of the surface protective pressure-sensitive adhesive film in FIG.

3 is a cross-sectional view of a main part showing still another example of the surface-protective pressure-sensitive adhesive film in FIG.

FIG. 4 is a partially enlarged sectional front view showing a part of a dust-removing pressure-sensitive adhesive mat formed by laminating a large number of surface-protective pressure-sensitive adhesive films of the present invention.

[Explanation of symbols]

 1 Base Film 1a, 1b, 1c Polyolefin Layer 2 Adhesive A Adhesive Film for Surface Protection B Adhesive Mat for Dust Removal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B29C 47/06 9349-4F B29C 47/06 B32B 27/00 B32B 27/00 M 27/30 27 / 30 A 27/32 27/32 C C08L 23/26 LDP C08L 23/26 LDP // D06M 17/00 D06M 17/00 C

Claims (4)

[Claims] 1. A single-layer polyolefin base film containing 10% or more of a composition obtained by mixing two or more ionomers partially or wholly neutralized with an alkali metal containing potassium. A pressure-sensitive adhesive film for surface protection, comprising a curing reaction type acrylic pressure-sensitive adhesive applied on one side of the film. 2. A polyolefin single layer containing 10% or more of a composition obtained by mixing two or more ionomers which are partially or wholly neutralized with an alkali metal containing potassium, and a polyolefin layer containing no ionomer. And a curing reaction-type acrylic pressure-sensitive adhesive coated on one side of the base film. Adhesive film for surface protection. 3. A polyolefin single layer containing 10% or more of a composition obtained by mixing two or more ionomers, which are partially or wholly neutralized with an alkali metal containing potassium, and a polyolefin layer containing no ionomer. And a multi-layered base film having a thickness ratio in the range of 1: 4 to 1: 1 and a total thickness in the range of 35 to 120 μ, A pressure-sensitive adhesive film for surface protection, comprising a curing reaction type acrylic pressure-sensitive adhesive applied on one side of a base film. 4. A polyolefin single-layer base film containing 10% or more of a composition obtained by mixing two or more ionomers which are partially or wholly neutralized with an alkali metal containing potassium, or A base film made of a multilayer consisting of 2 to 3 layers by co-extrusion of a polyolefin single layer and the polyolefin containing no ionomer, and a curing reaction type acrylic pressure-sensitive adhesive coated on one side of the base film. A dust-removing pressure-sensitive adhesive mat, comprising a multiplicity of laminated surface protection pressure-sensitive adhesive films.