JP2016017167A - Double-sided adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce a double-sided adhesive tape whose adhesive layer is formed in a stripe-like shape with a plurality of rows.SOLUTION: A monolayer adhesive layer tape 32 with an adhesive layer 31a is produced by forming a storage part 5 of an adhesive composition A at the upstream of a gap 4 of a coating applicator having the gap 4 to pass a base material film 10, and passing the base material film 10 through the gap 4 so as to apply the adhesive composition A to the one surface of the base material film 10. In the case, a stripe application film 20 provided with a plurality of slits 21 is arranged in the gap 4 to pass the base material film 10 so as to let the slits 21 cross the narrowest part of the gap 4, and the adhesive composition A is applied to the base material film 10 in a stripe-like shape with a plurality of rows by passing the base material film 10 through the gap 4 so as to form the adhesive layer 31a in a stripe-like shape with a plurality of rows. Then, the monolayer adhesive layer tape 32 thus obtained is used so as to produce a double-sided adhesive tape 30A.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a double-sided pressure-sensitive adhesive tape.

  When attaching an LCD panel or LCD panel film to the backlight housing of the LCD module, it is attached to the LCD module so that it can be repaired for convenience such as inspection after assembly and replacement of parts. Adhesive tape is used.

  However, there are some sticking surfaces of the LCD panel or LCD panel film and the LCD module backlight housing that have a sticking surface, and such a sticking surface has a solid adhesive surface. When pasting with a conventional double-sided pressure-sensitive adhesive tape, stress is applied to the pasting site, and strain and wrinkles may occur.

  Therefore, when sticking the warped sticking surface with a double-sided adhesive tape, it is possible to cut the double-sided adhesive tape thinly and stick it in multiple rows of lines, but workability is improved. There is a problem of lowering.

  On the other hand, regarding a double-sided pressure-sensitive adhesive tape, a striped release agent layer along the longitudinal direction of the base film is provided on one side of the base film, and a striped release agent along the longitudinal direction is provided on the other side of the base film. In this case, the release agent layers on the front and back sides of these substrates are arranged alternately, and then an adhesive layer is formed on the substrate provided with the release agent layer, which is wound around a roll. Has been proposed (Patent Document 1). When the tape-like double-sided adhesive tape was pulled out from this roll, the adhesive layer was divided into stripes, and the strips of the release agent layer and the stripes of the adhesive layer were alternately formed on both the front and back surfaces of the tape-like substrate. A double-sided adhesive tape can be obtained. Therefore, it is conceivable to use this double-sided adhesive tape when the adherend surface of the adherend is warped.

  However, the manufacturing method of this double-sided pressure-sensitive adhesive tape is complicated, and when the tape-like double-sided pressure-sensitive adhesive tape is unwound from the roll, the pressure-sensitive adhesive layer may not be divided into intended stripes.

Japanese Patent Laid-Open No. 2001-181584

  In contrast to the above-described conventional technology, the problem of the present invention is a double-sided pressure-sensitive adhesive tape in which an adhesive layer is formed in a plurality of lines, which can be easily manufactured and has excellent removability. Relating to providing.

  The present inventor uses a coating device such as a roll coater to apply a pressure-sensitive adhesive composition to a base film, and uses a stripe coating film having a plurality of rows of slits. It has been found that a single-layer adhesive layer tape formed in a streaky shape can be easily manufactured by utilizing an existing coating apparatus, and a double-sided adhesive tape can also be easily manufactured using this single-layer adhesive layer tape. Was completed.

  That is, the present invention provides a pressure-sensitive adhesive composition by forming a reservoir of the pressure-sensitive adhesive composition upstream of the gap of a coating apparatus having a gap through which the base film passes, and passing the base film through the gap. A method for producing a single-layer adhesive layer tape that is applied to one side of a base film to form an adhesive layer, wherein a slit coating film having a plurality of slits arranged in parallel in the gap through which the base film is passed. Is disposed so as to straddle the narrowest part of the gap, the adhesive composition is applied to the base film that has passed through the gap in a plurality of lines, and the adhesive layer is formed in a plurality of lines. A method for producing a single-layer adhesive layer tape to be formed is provided.

  Moreover, this invention manufactures the single layer adhesive layer tape which formed the 1st adhesion layer in the 1st base film by the above-mentioned method, and laminated | stacked the 2nd base film on the 1st adhesion layer. In this case, one of the first base film and the second base film is a release film, and the other is a non-release film having a higher adhesive force to the adhesive layer than the release film, and the single-layer adhesive thus obtained Provided is a method for producing a double-sided pressure-sensitive adhesive tape in which a second pressure-sensitive adhesive layer is formed on the outer surface of a non-peeling film of a layer tape.

  In addition, the present invention has, as a double-sided pressure-sensitive adhesive tape manufactured by the above-described double-sided pressure-sensitive adhesive tape manufacturing method, a plurality of rows of first adhesive layers formed in a stripe shape on one side of a non-release film, Provided is a double-sided pressure-sensitive adhesive tape having a second adhesive layer on the other surface of the film and having a release film laminated on the adhesive layer of the first adhesive layer.

  According to the double-sided pressure-sensitive adhesive tape of the present invention, since at least one of the double-sided pressure-sensitive adhesive layers of the base film is formed in a plurality of lines, even when bonding adherends with sticking surfaces warped, The stress on the sticking surface can be relaxed at a portion where the streaky portion of the adhesive layer is absent. Therefore, distortion and wrinkles can be prevented from occurring on the adherend. Moreover, air can be easily extracted from the sticking surface of a to-be-adhered body because the adhesion layer is formed in the shape of a plurality of lines.

  Furthermore, the adhesive force between the adherend and the double-sided pressure-sensitive adhesive tape can be easily controlled by changing the width of the streaky portion of the adhesive layer, and the work efficiency of re-peeling and re-adhering the adherend can be improved. it can.

  In addition, the double-sided pressure-sensitive adhesive tape of the present invention has a stripe coating film in which a plurality of slits are juxtaposed in the gap through which the base film of the coating device passes, so that the slit straddles the narrowest portion of the gap. Thus, it can be easily manufactured using an existing coating apparatus. Moreover, the stripe width | variety of an adhesion layer can be easily changed into a desired width | variety by replacing | exchanging a stripe coating film.

FIG. 1A is a cross-sectional view of the coating unit. FIG. 1B is a top view of the coating unit. FIG. 1C is an XX side view of the coating unit. FIG. 2 is a plan view of the line coating film. FIG. 3A is a cross-sectional view of the manufacturing process of the double-sided pressure-sensitive adhesive tape 30A. FIG. 3B is a cross-sectional view of the manufacturing process of the double-sided pressure-sensitive adhesive tape 30A. FIG. 3C is a cross-sectional view of the manufacturing process of the double-sided pressure-sensitive adhesive tape 30A. FIG. 3D is a cross-sectional view of the double-sided adhesive tape 30A. FIG. 4 is a cross-sectional view of the double-sided adhesive tape 30A '. FIG. 5 is a cross-sectional view of the double-sided pressure-sensitive adhesive tape 30B. FIG. 6 is a cross-sectional view of the double-sided pressure-sensitive adhesive tape 30C. FIG. 7 is a cross-sectional view of the double-sided adhesive tape 30D. FIG. 8 is a cross-sectional view of the double-sided pressure-sensitive adhesive tape 30E. FIG. 9 is a cross-sectional view of the double-sided pressure-sensitive adhesive tape 30F. FIG. 10 is a cross-sectional view of the double-sided pressure-sensitive adhesive tape 30G.

Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol represents the same or equivalent component.
1. Coating device
1-1 Outline of Coating Device FIG. 1A is a schematic cross-sectional view of an example of a coating unit of a coating device used in the method for producing a double-sided tape of the present invention, FIG. 1B is a top view thereof, and FIG. -X is a side view.
The coating unit 1 has a drive roll 2 and a gap roll 3 facing the drive roll 2, and a reservoir for the adhesive composition A upstream of the gap 4 between the drive roll 2 and the cap roll 3. 5 and the adhesive coating A supplied from the storage section 5 is applied to the base film 10 so that an adhesive layer is formed. It is a thing.

  Here, the drive roll 2 is made of metal and formed in a columnar shape, rotates in the direction of the arrow, and transports the base film 10. In the figure, the symbol P is the rotation axis of the drive roll 2.

  The gap roll 3 is made of metal and has a cylindrical shape, and may or may not rotate. When rotating the gap roll 3, a scraping knife 8 is provided on the peripheral surface of the gap roll 3, and the pressure-sensitive adhesive composition A adhering excessively to the gap roll 3 is scraped off from the surface of the gap roll 3. The gap roll 3 of the coating unit may be anything that can adjust the gap 4 to a predetermined size with respect to the drive roll 2. Instead of the gap roll 3, a gap device having a non-cylindrical shape is used. Also good.

The size of the gap 4 (i.e., the distance between the driving roller 2 and the gap roll 3) L _G is a numerical value calculated according to the solids content of the pressure-sensitive adhesive composition A to be coated and the thickness of the adhesive layer with a target And the thickness L _F of the base film 10 and the total thickness L 0 of the stripe coating film 20 described later.

  A dam plate 6 is provided upstream of the gap 4 in the moving path of the base film 10 moved by the drive roll 2 so that one end of the dam plate abuts against the drive roll 2. The side plate 7 extends so as to abut against the drive roll 2 and the gap roll 3. And the area | region enclosed by the dam plate 6, the side plate 7, the drive roll 2, and the gap roll 3 is the storage part 5 which accumulates the adhesive composition A. As shown in FIG.

  One side region of the line coating film 20 is adhered to the back surface of the dam plate 6 (outside the storage portion 5). The remainder of the stripe coating film 20 extends in the driving direction of the drive roll 2 along the outer surface of the drive roll 2, and the tip of the stripe coating film 20 is the narrowest portion of the gap 4 between the drive roll 2 and the gap roll 3. More downstream.

1-2 Muscle Coating Film FIG. 2 is a plan view of the muscle coating film 20. The stripe coating film 20 is a substantially rectangular film, covers the bottom of the reservoir 5 so that the adhesive composition A does not adhere to the base film 10 in the reservoir 5 of the coating unit 1 and is disposed downstream. A plurality of slits 21 extending in the moving direction of the base film 10 are arranged in parallel at the end portion, whereby one side of the rectangle is comb-like.

  The film material constituting the line coating film 20 is preferably a firm material such as PET, PID, or OPP, and preferably has a smooth surface. The strip coating film 20 may be subjected to a mold release process.

  The thickness L0 of the line coating film 20 is determined according to the target thickness of the line-shaped adhesive layer formed on the base film 10 and the solid content of the pressure-sensitive adhesive composition A. For example, when the target thickness of the adhesive layer is 30 to 70 μm, the thickness L 0 of the muscle coating film 20 is preferably 25 to 200 μm, more preferably 50 to 188 μm.

  In the line coating film 20, the shape of the slit 21 is a strip shape, but it is preferable that the upstream end portion of the slit 21 in the case where the slit 21 is disposed in the coating unit is rounded. Thereby, the part which protruded in the comb-tooth shape of the film for line | wire coating becomes difficult to fracture | rupture during the application | coating process of an adhesive composition.

  The length L1 of the slit 21 is set to a length sufficient to straddle the narrowest portion of the gap 4 between the drive roll 2 and the gap roll 3 as shown in FIG. 1B. In FIG. 1B, the line of the narrowest part of the gap 4 between the drive roll 2 and the gap roll 3 overlaps with the rotation axis P of the drive roll 2. Therefore, the projection line of the rotation axis P onto the stripe coating film 20 when the stripe coating film 20 is installed in the coating unit is a straight line Q indicating the narrowest portion of the gap 4. It is preferable that the distance L2 between the downstream end of the line coating film 20 and the straight line Q when the line coating film 20 is disposed in the coating unit 1 is 10 to 200 mm. Thereby, it becomes possible to form the adhesive composition A on the base film 10 in a streak shape corresponding to the width of the slit 21 of the streaked film 20.

  The distance L3 between the straight line Q and the upstream end of the slit 21 is preferably the distance between the dam plate 6 and the straight line Q. If the distance L3 is too short, the supply amount of the pressure-sensitive adhesive composition A is insufficient, so that the pressure-sensitive adhesive composition A cannot be applied to the base film 10, and if the distance L3 is too long, the slit 21 is easily distorted. .

  Therefore, the length L1 of the slit is preferably 200 to 300 mm as the distance from the straight line connecting the points where the pair of dam plates 6 hit the drive roll 2 to the downstream end of the line coating film 20.

  The width of the streaky portion of the pressure-sensitive adhesive composition A applied to the base film 20 varies depending on the width L4 of the slit 21. The width L4 is determined according to the viscosity of the pressure-sensitive adhesive composition A, the size of the gap 4, and the like. Usually, it is preferably 20 to 30 mm, more preferably 20 to 25 mm.

  The distance between the streaky portions of the pressure-sensitive adhesive composition A applied to the base film 20 varies depending on the distance L5 between the adjacent slits 21. This distance L5 is determined according to the viscosity of the pressure-sensitive adhesive composition A, the size of the gap 4, and the like. Usually, it is preferably 30 to 40 mm, more preferably 35 to 40 mm.

  In addition, when manufacturing a single layer adhesive layer tape, compared with the case where the adhesive layer manufactures the double-sided adhesive tape currently formed in the front and back of a base film, the width | variety L4 of the slit 21 is enlarged and the adjacent slit 21 is manufactured. It is preferable to reduce the distance L5.

2. Base Film As the base film 10, a release film having a high peelability for the adhesive layer or a non-release film having a peelability for the adhesive layer lower than that of the release film can be used as necessary.

As the release film, a film such as OPP or a film such as PET that has been subjected to a release treatment with silicone or the like can be used.
As the non-peeling film, a fluorine-based film that has not been peeled can be used.
The thickness L _F of the base film 10 is preferably 25 to 75 μm.

3. Adhesive composition and adhesive layer
3-1 Adhesive composition As the adhesive composition A, a solvent-type acrylic adhesive or the like generally used as an adhesive for an adhesive tape can be used. For example, an adhesive containing an acrylic polymer and a crosslinking agent Is preferred. If necessary, the pressure-sensitive adhesive composition A can contain a crosslinking accelerator, a dye, a pigment, an ultraviolet absorber, a surfactant, an antiaging agent, and the like.

  In addition, as the adhesive composition A, for example, a silicone-based adhesive, various rubber-based adhesives, a polyester-based adhesive, and the like can be used.

The pressure-sensitive adhesive composition so that the pressure-sensitive adhesive composition A applied to the base film 10 in a plurality of rows of stripes maintains the original stripe shape until the final form formed in the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape. A preferably has an elastic modulus of 10 ⁷ dyn / cm ² or less, preferably 10 ⁵ to 10 ⁶ dyn / cm ² .

3-2 Acrylic polymer The acrylic polymer constituting the pressure-sensitive adhesive composition is preferably a polymer having a weight average molecular weight of 500,000 or more, more preferably a weight average molecular weight of 700,000 to 1,500,000. When the molecular weight is insufficient, the removability is lowered, and when the molecular weight is excessively increased, the workability at the time of coating is lowered. In addition, after the adhesive composition is applied in a streak shape, the acrylic polymer is crosslinked by UV irradiation, heating, or the like.

  This weight average molecular weight can be measured by a gel permeation chromatograph (GPC) method. As the GPC measurement device, for example, Model 510 manufactured by Waters can be used.

The glass transition temperature (Tg) of the acrylic polymer is preferably −10 ° C. to −70 ° C., more preferably −20 ° C. to −50 ° C., from the viewpoint of improving the adhesive properties at low temperatures.
This glass transition temperature (Tg) is a glass transition temperature (theoretical value) represented by the following formula.
1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ +... W _n / Tg _n
Wherein, Tg is the glass transition temperature of the acrylic polymer (unit: K), Tg _n represents a glass transition temperature of the homopolymer of the monomer n (unit: K), W _n represents a weight fraction.

3-3 Acrylic polymer monomer (meth) acrylic acid ester having 1 to 12 carbon atoms (that is, acrylic acid ester or methacrylic acid ester) may be used as the monomer for forming the acrylic polymer. it can.

  Here, as specific examples of the (meth) acrylic acid ester having 1 to 12 carbon atoms, methyl acrylate, ethyl acrylate, butyl acrylate, 2-methyl acrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl acrylate, octyl Examples thereof include acrylate and dodecyl methacrylate. Among them, butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate and the like are preferable.

  The above-mentioned (meth) acrylic acid ester copolymerized with a reactive unsaturated monomer having at least one reactive group selected from a hydroxyl group, a carboxyl group, an amino group, and derivatives thereof in the molecule and a double bond. You may let them. Such reactive unsaturated monomers include acrylic acid, methacrylic acid, N-methylol acrylamide, glycidyl methacrylamide, allyl glycidyl ether, 2-hydroxyethyl acrylate, 2-hydroxy methacrylate, 2-hydroxypropyl acrylate, 2 -Hydroxy methacrylate, maleic anhydride, etc. can be mentioned. In particular, methacrylic acid and 2-hydroxymethacrylate are preferable. Two or more of these monomers may be used in combination.

  For the polymerization of the monomer, known radical polymerization methods such as solution polymerization, bulk polymerization, and emulsion polymerization can be appropriately selected. As the radical polymerization initiator, an azo initiator, a peroxide initiator, or the like can be used. That is, in the solution polymerization, for example, a polymerization initiator such as azobisisobutyronitrile is used in an amount of 0.01 to 0.2 parts by weight, and a polymerization solvent is used and a nitrogen stream is used at 50 to 70 ° C. for 8 to 30. Let react for hours. In this case, an organic solvent such as ethyl acetate or toluene is preferably used as the polymerization solvent, and the solution concentration is preferably 20 to 80% by weight. As a result, the polymer can have a high molecular weight as described above.

  From the viewpoint of reducing the environmental burden, a suspension polymerization method, an emulsion polymerization method and the like that do not use an organic solvent are preferable. In the suspension polymerization method and the emulsion polymerization method, for example, a polymerization initiator, a suspending agent (emulsifier), and a chain transfer agent as necessary are appropriately blended in water together with a monomer component containing an acrylic ester as a main component. And then polymerize. More specifically, emulsion polymerization methods such as a batch polymerization method, a continuous dropping polymerization method, and a divided dropping polymerization method can be employed.

Oil-soluble azo initiators and peroxide initiators can be used as the polymerization initiator in the suspension polymerization method. More specifically, 2,2′-azoisobutyronitrile, Azo initiators such as 2'-azobis-2,4-dimethylvaleronitrile, lauroyl peroxide, benzoyl peroxide, t-butyl-peroxy-2-ethylhexanoate, 1,1-di-t-butyl- Examples thereof include peroxide initiators such as peroxy-2-methylcyclohexane. These initiators may use only 1 type and may use 2 or more types together.
Moreover, water-soluble initiators, such as potassium persulfate and hydrogen peroxide, can be used for the polymerization initiator of an emulsion polymerization method.

Although the usage-amount of a polymerization initiator is not specifically limited, Preferably it is 0.01 to 5 weight% with respect to all the polymerizable monomer components, More preferably, it is 0.5 to 2 weight%. When the amount of the polymerization initiator used is too large, the water resistance of the coating film is lowered, and when it is too small, the polymerization rate is slowed and unreacted monomers are likely to remain, such being undesirable.
Moreover, the reaction conditions in the suspension polymerization method or the emulsion polymerization method can be appropriately selected, and the temperature is, for example, 20 to 100 ° C.

3-4 Crosslinking agents Crosslinking agents include isocyanate compounds, epoxy compounds, aldehyde compounds, amine compounds, metal salts, metal alkoxides, ammonium salts, hydrazine compounds, glycidyl compounds, aziridine compounds, metal chelates, etc. An isocyanate compound is preferable for improving the adhesion to 10. A single type of isocyanate compound may be used, or two or more types may be used in combination. Moreover, you may use together an isocyanate compound and another crosslinking agent.

  Specific examples of the isocyanate compound include tolylene diisocyanate, hydrogenated tolylene diisocyanate, tolylene diisocyanate adduct of trimethylol propane, xylylene diisocyanate adduct of trimethylol propane, triphenylmethane triisocyanate, methylenebis (4-phenylmethane) tri Examples thereof include isocyanate and isophorone diisocyanate, and examples thereof include ketoxime block products, phenol block products, and isocyanurates. Among these, tolylene diisocyanate adduct of trimethylpropane is preferable.

  The addition amount of a crosslinking agent such as an isocyanate compound is preferably 0.05 to 5 parts by weight, more preferably 0.1 to 1 part by weight with respect to 100 parts by weight of the acrylic resin. If the addition amount of the crosslinking agent is too small, the curing is not sufficiently performed, the cohesive force is insufficient, the removability is poor under high temperature and high humidity, and the adhesion is poor. On the other hand, if the addition amount of the crosslinking agent is too large, curing is excessively promoted and the adhesive strength is lowered, which is not preferable.

3-5 Adhesive layer Adhesive composition A is applied to a substrate film in a plurality of lines, dried as necessary, cured by UV irradiation or heating, and then cured into a plurality of lines. It becomes the adhesion layer. The final thickness of the adhesive layer is usually 5 to 70 μm.

4). Application Mechanism in Application Unit In the application unit 1 shown in FIG. 1A, the adhesive composition A is applied to the base film 10 as follows.
That is, the base film 10 is transferred by the drive roll 2 rotating in the direction of the arrow, and the base film 10 passes under the stripe coating film 20 on the bottom surface of the storage portion 5 in which the adhesive composition A is stored. Then, it passes through the gap 4 between the drive roll 2 and the gap roll 3. As shown in FIG. 1B, a muscle coating film 20 is disposed on the bottom surface of the storage portion 5, the muscle coating film 20 extends to the downstream of the gap 4, and a slit 21 is formed in a portion straddling the narrowest portion of the gap 4. Although formed, no slit is formed on the upstream side. Therefore, when the base film 10 passes through the bottom surface of the reservoir 5 upstream of the slit 21 formation region, the adhesive composition A does not adhere to the base film 10, but the base film 10 has the gap 4. When passing, as shown in FIG. 1C, an area in which a plurality of slits 21 of the line coating film 20 are juxtaposed overlaps with the base film 10 on the peripheral surface of the drive roll 2, and adhesion is made through the slits 21. The adhesive composition A is pressed against the base film 10 by the gap roll 3, and the adhesive composition A adheres to the base film 10.

  The plurality of rows of slits 21 of the stripe coating film 20 continue from the narrowest portion of the gap 4 to the length L2. For this reason, even after the base film 10 passes through the narrowest portion of the gap 4, the juxtaposed region of the slits 21 of the line coating film 20 overlaps the base film 10. Thereby, as shown to FIG. 1B, the adhesive composition A is apply | coated to the base film 10 corresponding to the position of the slit 21 of the line | wire coating film 20 in the shape of a plurality of lines.

  And by drying the adhesive composition A applied to the base film 10 in a plurality of lines, a single-layer adhesive layer tape in which a plurality of lines of adhesive layers are formed in a stripe on the base film 10 is obtained. Can be manufactured. Here, when the pressure-sensitive adhesive composition A contains a cross-linking agent, it can be cross-linked by performing UV irradiation, heating or the like during or after drying.

  On the other hand, when the juxtaposed region of the slits 21 of the stripe coating film 20 exists in the narrowest portion of the gap 4 and upstream thereof, but does not exist downstream of the narrowest portion of the gap 4, the adhesive composition The object A is not applied in a streak form but is applied in a planar form.

  In addition, the application unit which apply | coats the adhesive composition A to the base film 10 in the shape of a plurality of lines using the stripe coating film 20 is not restricted to what was shown to FIG. 1A. In a coating unit such as a known reverse coater, comma coater, gravure coater, roll coater, lip coater, die coater, etc., a stripe coating film is applied to the gap where the adhesive composition is adhered by passing the base film. The adhesive composition can be applied to the base film in a plurality of lines by attaching the slits so as to straddle the gap.

5. FIG. 3D is an example of a cross-sectional view of a double-sided pressure-sensitive adhesive tape manufactured using the coating unit 1 described above. This double-sided adhesive tape 30 </ b> A has a first adhesive layer 31 a formed in a plurality of lines on one side of the non-peeling film 12, and is formed in a plurality of lines on the other surface of the non-peeling film 12. It has the 2nd adhesion layer 31b, and peeling films 11a and 11b are laminated on these adhesion layers 31a and 31b, respectively.

Here, the first pressure-sensitive adhesive layer 31a and the second pressure-sensitive adhesive layer 31b are formed of the same pressure-sensitive adhesive composition, and the width L _a of the streaky portion of the first pressure-sensitive adhesive layer 31a and the second pressure-sensitive adhesive layer It is equal to the width L _b streaky portion 31b. Thereby, the adhesive force of the adhesive surface of the front and back of double-sided adhesive tape 30A becomes equal.
Further, the streak portions of the first adhesive layer 31a and the streak portions of the second adhesive layer 31b are alternately formed at positions that do not overlap each other with the non-peeling film 12 in between. Thereby, when winding double-sided adhesive tape 30A in roll shape, it can wind uniformly.

This double-sided adhesive tape 30A can be manufactured as follows.
First, the first release film 11a is used as the base film 10 used in the application unit 1, and the adhesive composition is applied onto the first release film in a plurality of lines in the manner described above. As shown in 3A, a single-layer adhesive layer tape 32 in which a plurality of rows of first adhesive layers 31a are formed on the first release film 11a is manufactured. In this case, as the line coating film 20 used in the coating unit 1, the width L4 of the slit 21 and the distance L5 of the adjacent slits 21 are made equal.

  In addition, although the single layer adhesive layer tape 32 can be wound and stored and can itself be used as a single layer adhesive tape, in this invention, it is used as an intermediate material for manufacturing a double-sided adhesive tape. .

  Next, as shown in FIG. 3B, the non-release film 12 is laminated on the adhesive layer 31 a of the single-layer adhesive layer tape 32, and the first adhesive layer 31 a is sandwiched between the first release film 11 a and the non-release film 12. A single-layer adhesive layer tape 33 is produced.

  In addition, the non-peeling film 12 is used as the base film 1 used in the coating unit 1, the adhesive composition A is applied to the non-peeling film 12 in a plurality of lines, and an adhesive layer is formed on the non-peeling film 12. Is manufactured in a plurality of lines, and the first release film 11a is laminated on the adhesive layer of the single-layer adhesive tape, whereby the single-layer adhesive layer tape shown in FIG. 33 may be manufactured.

  On the other hand, as shown in FIG. 3C, the second adhesive layer is formed in a plurality of rows of comb teeth on the second release film 11b in the same manner as in the case of manufacturing the single-layer adhesive layer tape 32 described above. Separately, the single-layer adhesive layer tape 32b is manufactured. And the non-peeling film 12 of the single layer adhesive layer tape 33 manufactured previously and the 2nd adhesive layer 31b of the single layer adhesive tape 32b manufactured separately are made to oppose these single layer adhesive layer tapes 33 and 32b. Laminate. In this case, the positions of the single-layer pressure-sensitive adhesive tapes 33 and 32b are adjusted so that the first pressure-sensitive adhesive layer 31a and the second pressure-sensitive adhesive layer 31b are alternately arranged without overlapping each other with the non-peeling film 12 in between. In this way, the double-sided pressure-sensitive adhesive tape 30A shown in FIG. 3D can be obtained.

  As another method for manufacturing the double-sided pressure-sensitive adhesive tape 30A, the position of the slit 21 of the stripe coating film 20 used for forming the first single-layer pressure-sensitive adhesive tape 32b is changed to the first of the first single-layer pressure-sensitive adhesive tape 32. A single layer in which the second single-layer adhesive layer tape 32b thus obtained and the non-peeling film 12 are laminated are shifted by a half pitch of the arrangement of the slits 21 with respect to the case where the adhesive layer 31a is formed. The adhesive layer tape 33 may be laminated so that the second adhesive layer 31b of the single-layer adhesive layer tape 32b and the non-release film 12 face each other.

  As another method for producing a double-sided pressure-sensitive adhesive tape, a base film 10 that applies a single-layer pressure-sensitive adhesive layer tape 33 in which a first pressure-sensitive adhesive layer 31 a is sandwiched between a first release film 11 a and a non-release film 12 to an application unit 1. As a result, the double-sided pressure-sensitive adhesive tape 30A ′ shown in FIG. 4 may be manufactured. In this double-sided pressure-sensitive adhesive tape 30A ′, the second pressure-sensitive adhesive layer 31b is formed in a plurality of lines on the non-peeling film 12 of the single-layer pressure-sensitive adhesive layer tape 33, but peeled off on the second pressure-sensitive adhesive layer 31b. Since the film is not laminated, it is wound and stored. Or it is good also as a double-sided adhesive tape of the same layer structure as FIG. 3D by laminating | stacking a peeling film on the 2nd adhesion layer 31b.

6). Deformation of double-sided pressure-sensitive adhesive tape In the method for producing a double-sided pressure-sensitive adhesive tape of the present invention, the width L4 of the slit 21 and the distance L5 (FIG. 2) between the adjacent slits 21 in the stripe coating film 20 used in the coating unit are appropriately changed. Moreover, the form as an adhesive tape is obtained by changing the slit width of the stripe coating film used for forming the first adhesive layer and the slit width of the stripe coating film used for forming the second adhesive layer. Can be diversified, and the removability can be finely adjusted, so that double-sided pressure-sensitive adhesive tapes of various modes corresponding to various adherends can be produced.

  For example, like the double-sided adhesive tape 30B shown in FIG. 5, the slit part 34a between the adjacent streaks of the first adhesive layer 31a and the slit part between the adjacent streaks of the second adhesive layer 31b. 34b can overlap each other with the non-peeling film 12 in between.

  This double-sided pressure-sensitive adhesive tape 30B is obtained by using, in the above-described method for manufacturing the double-sided pressure-sensitive adhesive tape 30A, as the stripe coating film 20, a distance L5 between adjacent slits 21 is larger than the width L4 of the slits 21. Can do.

  According to this double-sided pressure-sensitive adhesive tape 30B, since the pressure-sensitive adhesive layer is partially formed as compared with the above-mentioned double-sided pressure-sensitive adhesive tape 30A, a double-sided pressure-sensitive adhesive tape with improved removability can be obtained.

Like the double-sided pressure-sensitive adhesive tape 30 </ b> C shown in FIG. 6, the streaked portion of the first adhesive layer 31 a and the streaked portion of the second adhesive layer 31 b overlap each other with the non-peeling film 12 interposed therebetween. Good.
This double-sided pressure-sensitive adhesive tape 30C can be manufactured as the stripe coating film 20 by increasing the width L4 of the slit 21 with respect to the distance L5 between the adjacent slits 21 in the above-described method of manufacturing the double-sided pressure-sensitive adhesive tape 30A. .

  According to this double-sided pressure-sensitive adhesive tape 30C, it is possible to obtain a double-sided pressure-sensitive adhesive tape with improved adhesion compared to the above-mentioned double-sided pressure-sensitive adhesive tape 30A.

  Like the double-sided pressure-sensitive adhesive tape 30D shown in FIG. 7, the streaked portion of the first adhesive layer 31a and the streaked portion of the second adhesive layer 31b overlap each other with the non-peeling film 12 interposed therebetween, and the first The slit portion 34a of the adhesive layer 31a and the slit portion 34b of the second adhesive layer 31b may be overlapped with each other with the non-peeling film 12 in between.

  This double-sided pressure-sensitive adhesive tape 30D is obtained by laminating the non-peeling film 12 of the single-layer pressure-sensitive adhesive tape 33 and the separately-manufactured single-layer pressure-sensitive adhesive tape 32b in the above-described method for producing the double-sided pressure-sensitive adhesive tape 30A. It can be obtained by making the streaky portions overlap.

  According to the double-sided pressure-sensitive adhesive tape 30D, the narrow double-sided adhesive tape 30D is cut from the time when the double-sided pressure-sensitive adhesive tape 30D is manufactured or by cutting the slit portions 34a and 34b of the double-sided pressure-sensitive adhesive tape 30D in the direction in which the slit portions 34a and 34b extend. From the time when the pressure-sensitive adhesive tape is formed, an area where neither the first pressure-sensitive adhesive layer 31a nor the second pressure-sensitive adhesive layer 31b is formed is formed at the longitudinal edge of the double-sided pressure-sensitive adhesive tape 30D or the narrow double-sided pressure-sensitive adhesive tape. Therefore, even if the adhesive layers 31a and 31b are deformed by storing the double-sided pressure-sensitive adhesive tape 30D or the double-sided pressure-sensitive adhesive tape obtained by cutting the double-sided pressure-sensitive adhesive tape 30D in a high-temperature environment, blocking hardly occurs.

  As in the double-sided pressure-sensitive adhesive tape 30E shown in FIG. 8, in the above-described double-sided pressure-sensitive adhesive tape 30A, the width of the streaked portion of the second adhesive layer 31b is made wider than the width of the streaky portion of the first adhesive layer 31a. Similarly, like the adhesive tape 30F shown in FIG. 9, in the above-mentioned double-sided adhesive tape 30D, the second adhesive layer 31b with respect to the width of the streaked portion of the first adhesive layer 31a. The width of the streak portion may be widened. Thus, by making the width of the streaky portion of the second adhesive layer 31b wider than the width of the streaked portion of the first adhesive layer 31a, the first adhesive layer 31a of the double-sided adhesive tapes 30E and 30F. The adhesive force on the second adhesive layer 31b side can be increased more than the adhesive force on the side.

  Furthermore, as shown in the adhesive tape 30G shown in FIG. 10, one adhesive layer (the second adhesive layer 31b in the figure) on the front and back sides of the double-sided adhesive tape may be formed solid. Thereby, the adhesive force of the pressure-sensitive adhesive surface in which the pressure-sensitive adhesive layer is solid can be made even stronger than the adhesive force of the other pressure-sensitive adhesive surface.

  In addition, also in the double-sided pressure-sensitive adhesive tape shown in FIGS. 30B to 30G, the release film provided on the double-sided pressure-sensitive adhesive tape may be only one layer, similarly to the double-sided pressure-sensitive adhesive tape shown in FIG. 30A '.

Hereinafter, based on an Example, this invention is demonstrated concretely.
Examples 1 to 3 and Comparative Example 1
As shown in Table 1, as Examples 1 to 3, double-sided pressure-sensitive adhesive tapes having the cross sections shown in FIGS. 3D, 5 and 6 were manufactured in the steps shown in FIGS. 3A to 3C. Moreover, as Comparative Example 1, a double-sided pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer was formed on both surfaces of a base film (non-release film) and a release film was laminated on the pressure-sensitive adhesive layer was produced.

In this case, the width L _a of the streaked portion of the first adhesive layer, the width L _sa of the slit between the streaked portions of the first adhesive layer, the width L _b of the streaked portion of the second adhesive layer, The width L _sb of the slit between the streaky portions of the two adhesive layers is as shown in Table 1, and the thickness of each adhesive layer is 30 μm.

Moreover, the composition of the pressure-sensitive adhesive composition forming the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is as follows.
Polymer / Clearon P105 / Coronate HX
= 100/30/2
However,
Polymer = 2EHA / BA / VAc / AAc / HEMA
= 32/32/20/7/1
Clearon P105: Yasuhara Chemical Co., Ltd., hydrogenated terpene resin Coronate HX: Nippon Polyurethane Industry Co., Ltd., polyisocyanate

In the formula, 2EHA: 2-ethylhexyl acrylate BA: butyl acrylate VAc: vinyl acetate AAc: acrylic acid HEMA: hydroxyethyl methacrylate

  As the base film (non-release film 12), PET having a thickness of 25 μm was used, and as the release films 11a and 11b, release PET having a thickness of 38 μm was used.

Evaluation About the double-sided pressure-sensitive adhesive tapes of each Example and Comparative Example, (a) pasting property, (b) reworkability, (c) thickness uniformity, (d) presence or absence of occurrence of strain was evaluated as follows. . The results are shown in Table 1.

(a) Pasting property The ease of pasting when the LCD panel and the backlight housing were pasted together with a double-sided adhesive tape was evaluated according to the following criteria.
○: Air release is good and there is no breakage or wrinkle. △: Air release is bad but no breakage or wrinkle. ×: Air release is bad and breakage or wrinkle occurs.

(b) Reworkability After bonding the LCD panel and the backlight housing with a double-sided adhesive tape, the presence or absence of transfer of the adhesive when peeling them off was evaluated according to the following criteria.
○: No glue residue △: Some glue residue ×: There is glue residue on the entire surface

(c) Thickness uniformity The thickness uniformity of the double-sided adhesive tape itself was evaluated according to the following criteria.
◎: Thickness is uniform ○: Thickness is non-uniform but practically no problem ×: Thickness is non-uniform and practically hindered

(d) presence or absence of distortion,
After bonding the LCD panel and the backlight housing with a double-sided adhesive tape, the presence or absence of distortion was visually observed and evaluated according to the following criteria.
◎: No distortion ○: Slightly distorted but usable △: Slightly distorted but usable *: Distorted and unusable

  From Table 1, the adhesive layers on the front and back of the base film are formed in a plurality of lines, and the streaks are shifted on the front and back of the base film, so that (i) air is removed when the adherends are bonded together. (Ii) Since the stress when the bonded surface is bonded can be relaxed in the space portion of the adhesive layer, the bonded surface is warped. It can be seen that even if it is, it can be bonded with a predetermined adhesive force, and (iii) it is easy to re-peel after being bonded once.

  Among the examples, in particular, Example 2 in which the streaks of the adhesive layers on both sides of the base film do not overlap each other is particularly excellent in terms of air venting and reworkability, and the adhesive layers on both sides of the base film. Example 3 in which the streaky portions overlap each other was excellent in terms of adhesive strength.

DESCRIPTION OF SYMBOLS 1 Application | coating unit 2 Drive roll 3 Gap roll 4 Gap 5 Storage part 6 Dam plate 7 Side plate 8 Scraping knife 10 Base film 11a First release film 11b Second release film 12 Non-release film 20 Muscle coating film 21 Slit 30A, 30A ′, 30B, 30C, 30D Double-sided adhesive tape 31a First adhesive layer 31b Second adhesive layer 32 Single-layer adhesive layer tape 32b Second single-layer adhesive layer tape 33 Single-layer adhesive layer tape 34a First Slit part 34b of the adhesive layer Slit part of the second adhesive layer A Adhesive composition L0 Thickness of the film for line coating L1 Length of the slit L2 Straight line indicating the narrowest part of the gap M at the downstream end of the slit Distance from Q L3 Distance between upstream end of slit and straight line Q indicating the narrowest part of gap M L4 Width of slit L5 Distance between adjacent slits L _a first width L _F substrate film thickness size of L _G gap 4 of the resulting streaky portion of width L _b second adhesive layer streaky portion of the adhesive layer (the drive roll and the gap roll distance)
P Rotating shaft of the drive roll Q A straight line indicating the narrowest part of the gap

Claims (13)

  By forming a reservoir of the pressure-sensitive adhesive composition upstream of the gap of a coating apparatus having a gap through which the base film passes, and passing the base film through the gap, the pressure-sensitive adhesive composition is placed on one side of the base film. A method for producing a single-layer adhesive layer tape that is applied to form an adhesive layer, wherein a stripe coating film having a plurality of slits arranged in parallel in the gap through which a base film is passed, the slit being the narrowest of the gaps. The adhesive composition is applied to the base film in a plurality of lines by passing the base film through the gap and the adhesive layer is formed in a plurality of lines. A method for producing a single-layer adhesive layer tape.   A method for producing a single-layer adhesive layer tape comprising: forming a first adhesive layer on a first base film by the method according to claim 1; and laminating a second base film on the first adhesive layer. A method for producing a single-layer adhesive layer tape in which one of the first substrate film and the second substrate film is a release film, and the other is a non-release film having higher adhesion to the adhesive layer than the release film.   The manufacturing method of the double-sided adhesive tape which forms a 2nd adhesive layer in the outer surface of the non-peeling film of the single layer adhesive layer tape formed by the method of Claim 2.   A first single-layer adhesive layer tape is produced by the method of claim 2, while a second adhesive layer is formed on the release film by using a release film as a substrate film by the method of claim 1. Manufactured a second single-layer adhesive layer tape formed in a plurality of lines, and a non-release film of the first single-layer adhesive layer tape and a second adhesive layer of the second single-layer adhesive layer tape The method for producing a double-sided pressure-sensitive adhesive tape according to claim 3, wherein the first single-layer pressure-sensitive adhesive tape and the second single-layer pressure-sensitive adhesive tape are laminated so as to face each other.   The streaks of the first adhesive layer formed on the first single-layer adhesive layer tape and the streaks of the second adhesive layer formed on the second single-layer adhesive layer tape do not overlap each other. Thus, the manufacturing method of the double-sided adhesive tape of Claim 4 which laminates | stacks a 1st single layer adhesive layer tape and a 2nd single layer adhesive layer tape.   The streaks of the first adhesive layer formed on the first single-layer adhesive layer tape and the streaks of the second adhesive layer formed on the second single-layer adhesive layer tape are overlapped with each other. The method for producing a double-sided pressure-sensitive adhesive tape according to claim 4, wherein the first single-layer pressure-sensitive adhesive tape and the second single-layer pressure-sensitive adhesive tape are laminated together.   The first adhesive layer formed in a plurality of lines is formed on one side of the non-release film, the second adhesive layer is provided on the other side of the non-release film, and the release film is laminated on the first adhesive layer. Double-sided adhesive tape.   The double-sided pressure-sensitive adhesive tape according to claim 7, wherein the second pressure-sensitive adhesive layer is formed in a solid coating.   The double-sided pressure-sensitive adhesive tape according to claim 7, wherein the second pressure-sensitive adhesive layer is formed in a plurality of lines.   The double-sided pressure-sensitive adhesive tape according to claim 9, wherein the streaky portion of the first adhesive layer and the streaked portion of the second adhesive layer are formed at positions where they do not overlap each other with the non-peeling film interposed therebetween.   The double-sided pressure-sensitive adhesive tape according to claim 9, wherein the streaky portion of the first adhesive layer and the streaked portion of the second adhesive layer are formed at positions where they overlap each other with the non-peeling film interposed therebetween.   The slit part between the adjacent streak parts of the first adhesive layer and the slit part between the adjacent streak parts of the second adhesive layer are formed at positions where they overlap each other with the base film interposed therebetween. Item 12. A double-sided pressure-sensitive adhesive tape according to item 11.   The double-sided pressure-sensitive adhesive tape according to any one of claims 9 to 12, wherein the stripe width of the first adhesive layer and the stripe width of the second adhesive layer are different.

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