JPH10237396A - Adhesive type - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive tape suitable for masking use because of, for example, being good in hand cuttability, by applying a tack agent to a composite base material composed of a specific porous film and specific plastic films and having a specific initial modules. SOLUTION: This adhesive tape is obtained by laminating a tack agent layer at least on one side of a composite base material 20-150kg/mm<2> in initial modulus composed of (A) a porous film having 200-5,000/cm<2> of penetrating holes each 0.1-100μm in average opening size and (B) plastic films free from penetrating holes and provided on both sides of the porous film A. The thickness of the above composite base material is 10-300 (pref. 20-200)μm; and the thickness (after dried) of the above tack agent layer is 5-70 (pref. 10-50)μm. Thus, the objective adhesive tape can be provided so as to have the following advantages: easily releasable without causing any tear; and leaving no paste on an adherend with clear-cut reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an adhesive tape. More specifically, the present invention relates to a pressure-sensitive adhesive tape which has good hand-cutting properties when affixing the tape, does not tear the tape when peeled off, has excellent parting properties and weather resistance, and is suitable for masking applications.

[0002]

2. Description of the Related Art A masking adhesive tape (hereinafter, referred to as "masking tape") is attached to a vehicle or a building for painting or sealing during construction. The following characteristics are required for the masking tape. When applying the tape, it can be easily torn by hand, without tearing after serving the purpose of masking,
It can be peeled off from the adherend. After peeling off the tape, no adhesive remains on the adherend (no glue remains). In particular, in a coating application, the boundary between the painted portion and the unpainted portion has linearity (partitioning property).

Conventional masking tapes include an adhesive tape using a paper base made of Japanese paper or crepe paper as a base material, and a plastic base material provided with through holes or non-through holes for imparting hand-cutting properties. Has been used.

[0004]

However, in the case of an adhesive tape using a paper base material, although the hand-cutting property is good, when the adhesive tape is torn when peeled from an adherend or used for coating purposes, There is a problem that the paint oozes into the non-painted part due to the capillary phenomenon and the parting property cannot be sufficiently obtained. In addition, a primer used at the time of masking (an undercoat of a sealing material applied to improve the adhesion between the sealing material and the frame when filling the sealing material)
In addition, there is also a problem that the solvent in the paint runs off from the base material side to expand and dissolve the pressure-sensitive adhesive, thereby causing adhesive residue on the adherend.

[0005] In the case of an adhesive tape using a plastic substrate provided with a through-hole, the hand-cutting property is good, it does not tear when peeled, and the parting property is good to some extent. Therefore, there is a problem that glue remains on the adherend.

In the case of an adhesive tape using a plastic substrate having a non-through hole, it does not tear when peeled off.
In addition, although the parting property and the adhesive residue on the adherend are good, there is a problem that the non-through hole is provided, so that the hand cutting property is not good.

An object of the present invention is that it is suitable for masking applications that have good hand-cutting properties, do not tear when peeled after fulfilling the purpose, do not leave glue on the adherend, and have good parting properties. The purpose is to provide an adhesive tape.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have found that a substrate on which an adhesive is to be applied is formed into a through-hole having a specific average opening diameter. It has been found that the above object can be achieved by making a composite substrate having a specific initial elastic modulus, which is composed of a porous film perforated at a density and a plastic film having no through holes, and completes the present invention. Reached.

That is, the present invention provides an average opening diameter of 0.1 to 10
An initial elastic modulus of 2 including a porous film having 200 to 5,000 through-holes / cm ^{2 of} 0 μm and a plastic film having no through-holes provided on both sides of the film.
The present invention relates to a pressure-sensitive adhesive tape including a composite base material having a weight of 0 to 150 kg / mm ² and a pressure-sensitive adhesive layer.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The adhesive tape of the present invention has an average opening
200 to 5,000 through holes with a diameter of 0.1 to 100 μm
/ Cm^TwoPorous film and the film on both sides
A plastic film having no through-hole to be drilled,
Initial elastic modulus is 20-150kg / mm ^TwoIs a composite substrate
The adhesive layer is laminated on at least one side of
You.

The porous film used in the present invention has through holes having an average opening diameter of 0.1 to 100 μm in a range of 200 to 5,
000 holes / cm ^{2 were} perforated. Average opening diameter is 5
~ 80 µm is preferred. If the average opening diameter is less than 0.1 μm, the hand-cutting property of the adhesive tape is not good,
If it exceeds 0 μm, the tape tends to cut off intermittently when peeled from the adherend.

The shape of the through hole is not particularly limited, and may have an elliptical or slit shape as well as a perfect circle. The average opening diameter is measured using a microscope or a device such as a loupe, and in the case of an elliptical or slit-shaped through hole, the long diameter is measured.

[0013] The lower limit of the density of the through holes is 200 / cm ² with respect to the porous film, preferably, 300 / cm ^2, more preferably 500 / cm ^2.
The upper limit is 5,000 / c for the porous film.
m ² , preferably 4,000 / cm ² , more preferably 3,000 / cm ² . The density of the through holes is 20
If the number is less than 0 pieces / cm ² , the hand-cutting property and the cut surface when cutting the adhesive tape tend to be poor, and
If it exceeds 00 / cm ² , the substrate tends to be cut when the adhesive tape is peeled off.

The method for forming the through-hole is not particularly limited, and a known method can be used. For example, a hot-melt piercing method, a method of mechanically piercing with a roll to which a large number of synthetic diamond particles or glass are adhered, and the like.

The plastic film having no through-hole used in the present invention is not particularly limited, and may preferably have a non-through-hole. The non-through hole preferably has a depth of 0 to less than 100% with respect to the thickness direction of the plastic film, and more preferably has a depth of 30 to 90%. Here, 0% means that there are no non-through holes, and less than 100% means that there are no through holes. If the through-holes are not formed, there is a tendency that no adhesive residue occurs due to strike-through of the paint, and the use of a plastic film can eliminate poor parting properties due to the capillary phenomenon seen in paper substrates and the like.

The method for forming the non-through hole is not particularly limited, and may be a known method. For example, there is a method in which the depth of a non-through hole is changed by changing the pressure at the time of bonding through a roll to which synthetic diamond or the like is adhered.

Examples of the film used for the porous film and the plastic film having no through-hole include a film made of a commonly used known resin, for example, polyethylene (PE), polypropylene (PP),
Expanded polypropylene (OPP), polyester, polyethylene terephthalate (PET), polyvinyl chloride (P
VC), a film composed of polyethylene naphthalate (PEN), polyphenylene sulfide (PPS) and an ethylene-vinyl acetate copolymer (EVA), and a film composed of a blend thereof.

The composite substrate used in the present invention is prepared by providing the plastic film on both sides of a porous film. The lamination method is not particularly limited, and a known method can be used. For example, lamination by a heating roll and use of an adhesive.

The composite base material has an initial elastic modulus of 20 to 15.
0 kg / mm^TwoAnd preferably 40 to 90 kg / m
m^TwoIt is. Initial elastic modulus is 20kg / mm^TwoIs less than
Tends to make masking work difficult (no linearity)
Yes, conversely 150kg / mm ^TwoOver, rough adherend
Tape does not tend to follow.

In the measurement of the initial elastic modulus, the composite substrate is cut in the flow direction to a width of 20 mm and a length of 100 mm to prepare a sample, and the sample is subjected to a universal tensile tester (RTM-10).
0, manufactured by Orientec Co., Ltd.), and set between 50 mm chucks, and a tensile test is performed at a tensile speed of 300 mm / min. A tangent line was drawn from the zero point of the chart drawn as the tensile strength, the strength at 100% was read from the gradient, and the value was used as the initial elastic modulus.

The composite substrate may be subjected to various known processes such as a back surface treatment, an undercoat, and a printing process, if necessary.

The thickness of the composite substrate is about 10 to 300 μm, preferably 20 to 200 μm. Specifically, the thickness of the porous film is about 5 to 200 μm, preferably 10 to 100 μm, and the thickness of the plastic film without through holes is about 2 to 100 μm, preferably 5 to 5 μm.
0 μm.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer used in the present invention is not particularly limited, and a known pressure-sensitive adhesive can be used. For example, a rubber-based pressure-sensitive adhesive, an acrylic-based pressure-sensitive adhesive, or the like can be used.

As the rubber-based adhesive, any of a natural rubber-based adhesive and a synthetic rubber-based adhesive may be used. Butyl rubber (IIR), butadiene rubber (B
R), styrene-butadiene rubber (SBR), isoprene rubber (IR), neoprene, polyisobutylene (PI
B), acrylonitrile-butadiene rubber (NBR),
Styrene-isoprene block copolymer (SIS), styrene-butadiene block copolymer (SBS), styrene-ethylene-butadiene block copolymer (SEB)
S) and the like.

Examples of the acrylic pressure-sensitive adhesive include homo- or copolymers of acrylic monomers such as ethyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and acrylic acid. Further, a monomer copolymerizable with the above-mentioned acrylic monomer may be used. The polymerization is not particularly limited, and examples thereof include solution polymerization and emulsion polymerization. Among them, acrylic pressure-sensitive adhesives are excellent in heat resistance and weather resistance.

In the pressure-sensitive adhesive layer, a crosslinking agent, a tackifier, a softener, an antioxidant, a filler, a pigment,
Known additives such as a stabilizer, a plasticizer, a release agent, a tackifier, and an antioxidant may be blended. The pressure-sensitive adhesive layer may be provided on at least one side of the substrate.

The thickness (after drying) of the pressure-sensitive adhesive layer is appropriately determined depending on the purpose, and is about 5 to 70 μm, preferably 1 to 70 μm.
0 to 50 μm.

If the thickness of the pressure-sensitive adhesive layer (after drying) is less than 5 μm, the adhesive strength is small, and the adhesive layer may be peeled off at the time of attaching the tape. Worse.

The production of the pressure-sensitive adhesive tape may be performed by a method known per se. For example, a method of applying and drying an adhesive on the composite substrate using a roll coater or the like, a method of applying the pressure-sensitive adhesive on a release liner, and then transferring the same may be used.

[0030]

EXAMPLES Examples and comparative examples are shown below, but the present invention is not limited by these examples. All parts mean parts by weight, and the biaxially oriented polypropylene and the uniaxially oriented polypropylene can change the elastic modulus depending on the degree of stretching.

Example 1 A porous film was formed on a 20 μm biaxially oriented polypropylene (OPP) film having a corona treatment on both surfaces by mechanical perforation to provide 1,000 through holes having an average opening diameter of 30 μm / cm ² . . On the film, an ink (Paramix 21) manufactured by Dainichi Seika Kogyo Co., Ltd. was printed, and polyethylene (PE) was laminated on both sides of the printed porous film so as to have a thickness of 20 μm. Materials were created. The initial elastic modulus of the composite substrate is as shown in Table 1 below. An acrylic pressure-sensitive adhesive [2-
Ethylhexyl acrylate: 98 parts, acrylic acid: 2
To the acrylic polymer obtained by copolymerization of 3 parts of an isocyanate-based cross-linking agent (Coronate L: Nippon Polyurethane Industry Co., Ltd.), and dried (thickness of the dried adhesive: 35 μm). I got

Example 2 An adhesive tape was obtained in the same manner as in Example 1 except that the thickness of the adhesive was changed to 45 μm.

Example 3 An adhesive tape was obtained in the same manner as in Example 1 except that the average opening diameter was 1 μm.

Example 4 An adhesive tape was obtained in the same manner as in Example 1 except that the average opening diameter was 90 μm.

Example 5 Example 1 was repeated except that the number of through holes was 300.
In the same manner as in the above, an adhesive tape was obtained.

Example 6 An adhesive tape was prepared in the same manner as in Example 1 except that the initial elastic modulus of the porous film (biaxial OPP film) was changed to 30 kg / mm ^2. I got

Example 7 The initial elastic modulus of the composite substrate was 130 kg / mm, using a porous film as a uniaxially oriented polypropylene (PP) film.
Except for using ^2, to obtain a pressure-sensitive adhesive tape in the same manner as in Example 1.

Example 8 The adhesive was a rubber-based adhesive [natural rubber: 70 parts, SBR: 3
0 parts, 60 parts of a petroleum resin (Quinton F-100: manufactured by Zeon Corporation) and 2 parts of a phenolic antioxidant (Nocrack NS-5: manufactured by Ouchi Shinko Chemical Co., Ltd.) The thickness of the adhesive after drying is 45 μm
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1, except that

Example 9 A polyester (PET) film was used in place of the biaxial OPP film, and a through-hole having an average opening diameter of 40 μm was provided with 900 holes / cm ^2.
m, amorphous polypropylene OPP (APP)
An adhesive tape was obtained in the same manner as in Example 1 except that the film was laminated.

[0040] except that the through-hole of Example 10 the average opening diameter 30μm provided 4,000 / cm ^2, to obtain a pressure-sensitive adhesive tape in the same manner as in Example 1.

Comparative Example 1 An adhesive tape was obtained in the same manner as in Example 1 except that instead of the composite base material, Japanese paper having a basis weight of 40 g / m ² was used.

Comparative Example 2 A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that a biaxial OPP film having a thickness of 20 μm and having been subjected to a double-sided corona treatment was used instead of the porous film. Was.

COMPARATIVE EXAMPLE 3 A porous film having a thickness of 60
% Except that a non-through hole having a depth of 1000% / cm ^{2 was} provided in the same manner as in Example 1.

Comparative Example 4 A biaxial OPP having a thickness of 50 μm and provided with 1,000 through holes / cm ² having an average opening diameter of 50 μm instead of the composite base material
An adhesive tape was obtained in the same manner as in Example 1 except that a film was used.

Comparative Example 5 Example 1 was repeated except that the average opening diameter was 0.05 μm.
In the same manner as in the above, an adhesive tape was obtained.

Comparative Example 6 An adhesive tape was obtained in the same manner as in Example 1 except that the average opening diameter was changed to 150 μm.

Comparative Example 7 Example 1 was repeated except that the number of perforations was 100.
In the same manner as in the above, an adhesive tape was obtained.

Comparative Example 8 An adhesive tape was obtained in the same manner as in Example 1 except that the porous film was a polyethylene film and the initial elastic modulus of the composite substrate was 10 kg / mm ² .

Comparative Example 9 The same procedure as in Example 1 was carried out except that the porous film was a uniaxially stretched polypropylene film, and a biaxial OPP film was laminated on both sides of the porous film so as to have a thickness of 20 μm. An adhesive tape was obtained.

Comparative Example 10 An adhesive tape was obtained in the same manner as in Example 1, except that 6000 through holes / cm ² having an average opening diameter of 30 μm were provided.

Using the composite substrates and the pressure-sensitive adhesive tapes obtained in Examples 1 to 10 and Comparative Examples 1 to 10 as samples, various items were evaluated. Each measuring method is as follows.

[Initial Elastic Modulus] The initial elastic modulus is obtained by cutting the obtained composite base material in the flow direction into a width of 20 mm and a length of 100 mm. The obtained sample is set between chucks of 50 mm using a universal tensile tester (RTM-100, manufactured by Orientec), and a tensile test is performed at a tensile speed of 300 mm / min. A tangent is drawn from the zero point of the chart drawn as tensile strength, and 100
The strength at% was read, and the value was taken as the initial elastic modulus.

[Hand-cutting property] The end face of the adhesive tape is 180 °
The adhesive tape was torn at a speed of 30 m / min in the direction, and the hand-cutting property of the adhesive tape was confirmed in the width direction of the tape. The evaluation is as follows. ：: The tape can be easily cut without extending the tape at the time of cutting. Δ: The cut is not very good, but if you get used to it, you can work. X: It is difficult to tear the tape during cutting, and the cut surface is dirty.

[Tearability when peeling tape] Stainless steel (B
A430) Adhesive tape of 18mm width (length 20c)
m), and put in a dryer at 80 ° C. for 2 hours.
After aging at 3 ° C for 3 hours, the adhesive tape was
The tearability of the tape when peeled at a speed of 30 m / min in the direction was confirmed. ：: The tape does not break at the time of peeling. X: The tape breaks during peeling.

[Parting-off] 50 mm
Attach an adhesive tape with a width (length 30 cm), and apply black paint (Nippe Car Spray, Nippon Paint Co., Ltd.) from above.
Was uniformly sprayed, the adhesive tape was peeled off, and the boundary between the painted portion and the unpainted portion was confirmed. ：: The boundary is very clear and linear. ×: The boundary is not clear, and the paint is slightly blurred even on the non-painted part.

[Glue Remaining Property] A 50 mm
Attach an adhesive tape with a width (length 30 cm), and apply black paint (Nippe Car Spray, Nippon Paint Co., Ltd.) from above.
Was uniformly sprayed, the adhesive tape was peeled off, and adhesive residue on the adherend was confirmed. ：: No adhesive residue. Δ: Slight adhesive residue. ×: There is adhesive residue.

The above measurement results are shown in Tables 1 to 4. In addition, の in the overall evaluation is suitable for a masking tape, and × means not suitable for a masking tape.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

[0062]

The pressure-sensitive adhesive tape of the present invention has good hand-cutting properties and does not tear when peeled after achieving the object.
It can be easily peeled off, and no adhesive remains on the adherend.
Since the parting property is good, it can be suitably used for masking applications and the like.

Claims (1)

[Claims] 1. An initial elasticity comprising a porous film having through holes of 200 to 5,000 / cm ² having an average opening diameter of 0.1 to 100 μm and a plastic film having no through holes provided on both sides of the film. Rate is 20-150kg
Pressure-sensitive adhesive tape comprising a composite base material and a pressure-sensitive adhesive layer having a thickness of / mm ² .