JP5671485B2 - Adhesive tape for conductive film and laminate for touch panel - Google Patents

Description

  The present invention relates to an adhesive tape for a conductive film used in a laminate for a touch panel and a laminate for a touch panel in which a member is attached using the adhesive tape.

  At present, the touch panel units mainly used are roughly classified into a resistance film type touch panel and a capacitance type touch panel, both of which are laminates of various materials. System adhesive is used. Since the touch panel unit is disposed on the outermost surface of the screen, the acrylic pressure-sensitive adhesive to be used is required to have high transparency, and further, characteristics such as high heat resistance and moisture heat resistance are required. Specifically, since the touch panel unit, which is a laminate of various materials, is disposed on the outermost surface of the touch panel device, whitening may occur due to the ingress of moisture from the outside. Foaming by entraining and foaming by outgas generated from the material to be laminated are problematic in that appearance defects occur.

  Moreover, in the resistive film type touch panel which has been the mainstream of touch panels so far, various adhesives have been used for attaching polycarbonate (PC) or in-mold film (IMD).

  However, as a characteristic of the PC material, outgas is generated under high temperature conditions, and since PC easily passes moisture, foaming occurs under heat resistant conditions, and the whitening phenomenon of the adhesive layer due to moisture inflow under wet heat conditions is suppressed. There is also the problem that it is difficult. Furthermore, since the IMD has a step of submicron order, there is also a problem that the pressure-sensitive adhesive cannot follow the step and bubbles are involved.

  Conventionally, the above problems have been solved by adding an acid component to the pressure-sensitive adhesive. In other words, the acid component has the function of dispersing the mixed water and preventing it from being deposited, and the water that has entered the pressure-sensitive adhesive layer is dispersed and not precipitated in the pressure-sensitive adhesive layer by the dispersion force of the acid component. The pressure-sensitive adhesive layer was prevented from being whitened and also formed with hydrogen bonds, so the generation of bubbles in heat-resistant foaming was suppressed by the high cohesive force due to the hydrogen bonds.

  Recently, with the enhancement of functions such as multi-touch, capacitive touch panels are becoming the mainstream instead of resistive touch panels. In this capacitive touch panel, the characteristics required for the resistive touch panel are of course necessary, but in addition, because the adhesive is in direct contact with the conductive layer forming the wiring, The property that the adhesive does not change the properties of the conductive layer is required. The conductive layer is made of a metal or metal oxide, such as indium tin oxide (ITO), which causes corrosion due to contact with acid and increases its resistance value. It is not possible to use means for securing characteristics such as heat resistance and heat-and-moisture resistance using

  Regarding the corrosion of such transparent electrodes made of metals such as ITO or metal oxides, Patent Document 1 (Japanese Patent Laid-Open No. 2010-77287) discloses a polymer mainly composed of alkoxyalkyl acrylate. In this Patent Document 1, it is disclosed to use an alkoxyalkyl acrylate polymer having a weight average molecular weight of 400,000 to 1.6 million and not using a carboxyl group-containing monomer.

  Thus, by using 400,000 to 1.6 million alkoxyalkyl acrylate polymers without using carboxyl group-containing monomers, the corrosion of transparent electrodes made of metals such as ITO or metal oxides is improved to some extent. However, sufficient effects are not obtained with respect to performance such as wet heat whitening and heat resistant foaming. Furthermore, workability is not sufficient.

  Furthermore, since the weight average molecular weight of the polymer disclosed in Patent Document 1 is as large as 400,000 to 1.6 million, the viscosity of the polymer solution increases when the solid content increases when this is dissolved in a solvent to prepare a coating solution. Is too high. In touch panel applications, particularly capacitive touch panel applications, it is necessary to form a thick adhesive layer in order to adhere a surface support and a conductive film such as ITO, but the weight average molecular weight is 400,000 to Since 1.6 million alkoxyalkyl acrylate polymers cannot be used to prepare a coating solution with a high solid content, it is necessary to prepare a coating solution with a low solid content and apply it repeatedly. There is a problem that it is difficult to form a pressure-sensitive adhesive layer having a thickness required for the work.

  In such a capacitive touch panel, an adhesive tape is directly attached to an electrode formed of ITO or the like. The adhesive tape stuck in this way has a property of shrinking as the curing reaction proceeds, while the ITO electrode does not have such a property of shrinking. For this reason, the phenomenon that the laminate of the ITO electrode and the adhesive tape curls as the curing reaction of the adhesive tape proceeds. In particular, such curl is prominent when the adhesive tape is hard.

JP 2010-77287 A

  The present invention relates to a pressure-sensitive adhesive for a touch panel having a conductive film made of a metal or a metal oxide, an adhesive tape excellent in heat resistance and moist heat resistance and not corrosive to a metal or metal oxide, and the use thereof The object is to provide a laminated body for a touch panel.

  Another object of the present invention is to provide a pressure-sensitive adhesive tape that is less likely to curl on an electrode such as ITO when it is attached to an electrode such as ITO, and a touch panel using the same.

The adhesive tape for conductive film of the present invention has the following components (a-1) to (a-4)
(a-1) 50-99.8% by weight of alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) hydroxyl group-containing monomer 0.1 to 10% by weight,
(a-3) Nitrogen-containing monomer 0.1 to 5% by weight and
(a-4) Alkyl (meth) acrylate 0 to 49.8% by weight
An acrylic polymer (A) having a weight average molecular weight of substantially 50,000 or more and less than 400,000, which is obtained by copolymerizing a monomer containing
One surface of a polyethylene terephthalate film having a thickness of 100 μm, having a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive having a gel fraction obtained from the isocyanate compound (B) in the range of 0 to 30% by weight A strip-shaped test piece coated with a pressure-sensitive adhesive with a dry thickness of 25 μm and cut to a width of 10 mm was attached to the surface of the glass substrate so that the adhesion area was 10 mm × 10 mm, and the strip-shaped test piece was The value of the minute creep test, which is the deviation width of the strip-shaped test piece with respect to the glass substrate when measured after 20 minutes after applying a weight of 800 g to the end not bonded to the glass substrate, is in the range of 7 mm to 9 mm. It is characterized by being.

  That is, the present invention is formed soft so that the value of the micro creep test of the adhesive tape represented by the micro creep test is 7 to 9 mm. By making the pressure-sensitive adhesive tape soft in this way, internal stress generated between the pressure-sensitive adhesive tape and the electrode when adhered to an electrode such as ITO can be absorbed by the soft pressure-sensitive adhesive tape. Therefore, by sticking an electrode such as ITO using the pressure-sensitive adhesive tape of the present invention, it is possible to reduce the curl generated in the laminate on which the electrode such as ITO is stuck.

Furthermore, the laminate for a touch panel of the present invention is
The following components (a-1) to (a-4)
(a-1) 50-99.8% by weight of alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) hydroxyl group-containing monomer 0.1 to 10% by weight,
(a-3) Nitrogen-containing monomer 0.1 to 5% by weight and
(a-4) Alkyl (meth) acrylate 0 to 49.8% by weight
An acrylic polymer (A) having a weight average molecular weight of substantially 50,000 or more and less than 400,000, which is obtained by copolymerizing a monomer containing
One surface of a polyethylene terephthalate film having a thickness of 100 μm, having a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive having a gel fraction obtained from the isocyanate compound (B) in the range of 0 to 30% by weight A strip-shaped test piece coated with a pressure-sensitive adhesive with a dry thickness of 25 μm and cut to a width of 10 mm was attached to the surface of the glass substrate so that the adhesion area was 10 mm × 10 mm, and the strip-shaped test piece was The value of the minute creep test, which is the deviation width of the strip-shaped test piece with respect to the glass substrate when measured after 20 minutes after applying a weight of 800 g to the end not bonded to the glass substrate, is in the range of 7 mm to 9 mm. It is characterized in that an adhesive tape for a conductive film and a transparent electrode layer are laminated.

In the adhesive tape for conductive films and the laminate for touch panel of the present invention, the glass transition temperature (Tg) of the acrylic polymer (A) is usually in the range of -70 ° C to 0 ° C.
Moreover, in the adhesive tape for electrically conductive films of this invention, and the laminated body for touchscreens, an adhesive tape is an adhesive tape for capacitive touch panels which usually contacts a metal or a metal oxide directly.

Furthermore, in the adhesive tape for electrically conductive films and the laminated body for touch panels of this invention, the average thickness of an adhesive tape is normally in the range of 10-1000 micrometers by dry thickness.
Furthermore, in the adhesive tape for electrically conductive films and the laminated body for touch panels of this invention, an adhesive tape is a double-sided adhesive tape, and this double-sided adhesive tape does not have a support body in the center vicinity of the thickness direction.

  Since the adhesive tape for conductive films of the present invention does not substantially contain an acid component, it can effectively suppress deterioration due to corrosion of a metal or metal oxide such as silver, ITO, ATO, or tin oxide. it can.

  Furthermore, in the adhesive tape for electrically conductive films of this invention, since the weight average molecular weight (Mw) of the adhesive to be used is 50,000 or more and less than 40, solid content can be kept in a high density | concentration in a solvent. A sufficient thickness can be applied in the coating process.

  In the present invention, since a suitable amount of a crosslinked structure is formed on the functional group of the acrylic polymer by the isocyanate-based crosslinking agent, the adhesive tape for a conductive film of the present invention is excellent in heat resistance and moist heat resistance, Moreover, it has very good step following ability.

  Therefore, the pressure-sensitive adhesive tape for conductive film of the present invention and the laminate for touch panel using this pressure-sensitive adhesive tape are less susceptible to corrosion to transparent conductive films made of metals or metal oxides such as ITO, ATO, and tin oxide. There is little variation in the electrical properties of the film, and whitening and foaming are less likely to occur.

  In particular, the pressure-sensitive adhesive tape for conductive films of the present invention has a soft pressure-sensitive adhesive expressed by a micro creep test, and even if a dimensional change occurs due to the curing reaction of the pressure-sensitive adhesive tape, the internal stress caused by the dimensional change is expressed by the pressure-sensitive adhesive tape. Therefore, warpage deformation hardly occurs in the laminate for a touch panel of the present invention. Therefore, the electrodes to be miniaturized can be reliably connected, and electrical connection can be ensured reliably.

FIG. 1 is a cross-sectional view schematically showing an example of a touch panel unit in a resistive film type touch panel incorporating the laminate for a touch panel of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a touch panel unit in a capacitive touch panel incorporating the laminate for a touch panel of the present invention. FIG. 3 is a cross-sectional view schematically showing an example of the configuration of the end of the capacitive touch panel. FIG. 4 is a cross-sectional view schematically showing the adhesive state of the adhesive tape to the frame print portion formed at the end of the touch panel. FIG. 5 is a cross-sectional view for explaining the state of foaming that occurs in the laminate for a touch panel. FIG. 6 is a cross-sectional view for explaining the occurrence of a whitening phenomenon that occurs in the laminate for a touch panel. FIG. 7 is a diagram for explaining a measurement method of a minute creep test. FIG. 8 is a diagram for explaining a method for measuring curl (amount of warpage) of a laminate of an ITO electrode and an adhesive tape.

Next, the adhesive tape for electrically conductive films and the laminated body for touch panels of this invention are demonstrated concretely.
The adhesive which forms the adhesive tape for electrically conductive films of this invention consists of an acrylic polymer (A) and an isocyanate type crosslinking agent (B).

In the present invention, the acrylic polymer (A) comprises the following components (a-1) to (a-4)
(a-1) alkoxy (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) a hydroxyl group-containing monomer,
(a-3) Nitrogen-containing monomer and, if necessary
(a-4)) A polymer obtained by copolymerizing an alkyl (meth) acrylate.

  Examples of (a-1) alkoxy (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate constituting the acrylic polymer (A) used here include 2-methoxymethyl (meth) acrylate, 2- Methoxyethyl (meth) acrylate, 2-ethoxyethyl acrylate, methoxydiethylene glycol (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 4-ethoxy Butyl (meth) acrylate can be mentioned, and among these (a-1) alkoxyalkyl (meth) acrylate and alkoxy polyalkylene glycol (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate It is preferred to use acrylates, which can be used alone or in combination.

  In the acrylic polymer (A) of the present invention, the above-mentioned (a-1) alkoxyalkyl (meth) acrylate is 50 to 99.8% by weight, preferably 100% by weight of the total amount of the acrylic polymer (A), preferably Copolymerization is carried out in an amount of 50 to 99.3% by weight, more preferably 50 to 98.6% by weight. (a-1) When the amount of alkoxyalkyl (meth) acrylate or alkoxypolyalkylene glycol (meth) acrylate is more than 99.8% by weight, the amount of the monomer having a crosslinkable functional group is inevitably reduced and sufficient crosslinking is performed. The density cannot be achieved. On the other hand, when it is less than 50% by weight, the whitening resistance of the pressure-sensitive adhesive of the present invention is lowered.

  The above (a-1) alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate is copolymerized to form an acrylic polymer (A) (a-2) a hydroxyl group-containing monomer is a crosslinkable functional group It is a (meth) acrylate compound having a hydroxyl group as a group. Examples of such hydroxyl group-containing monomers include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) Examples thereof include acrylate, 6-hydroxyhexyl (meth) acrylate, and 8-hydroxyoctyl (meth) acrylate. As the hydroxyl group-containing monomer as described above, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are preferable, and these hydroxyl group-containing monomers can be used alone or in combination.

  In the acrylic polymer of the present invention, the (a-2) hydroxyl group-containing monomer is 0.1 to 10% by weight, preferably 0.5 to 9% by weight, in 100% by weight of the acrylic polymer (A). The copolymerization is preferably carried out in an amount of 1 to 8% by weight. (a-2) When the content of the hydroxyl group-containing monomer is more than 10% by weight, the crosslinking density becomes high and the pressure-sensitive adhesive of the present invention cannot maintain a soft structure. On the other hand, if the amount is less than 0.1% by weight, a crosslinked structure cannot be effectively formed, the water resistance is lowered, the strength required for the crosslinked sheet is not exhibited, and the amount of deviation as a result of the micro creep test is large. Too much.

In the present invention, the acrylic polymer (A) is formed by copolymerization with the above (a-1) alkoxyalkyl (meth) acrylate and (a-2) a hydroxyl group-containing monomer and / or alkoxypolyalkylene glycol (meth) acrylate ( a-3) Examples of nitrogen-containing monomers include amino group-containing monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate,
Amide group-containing monomers such as (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-hexyl (meth) acrylamide,
Nitrogen-containing heterocycle-containing monomers such as vinylpyrrolidone, acryloylmorpholine, vinylcaprolactam,
Cyano group-containing monomers such as cyano (meth) acrylate Maleimides such as maleimide monomers such as maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide and cyclohexylmaleimide Mention may be made of group-containing monomers.

  In the acrylic polymer (A) of the present invention, the above (a-3) nitrogen-containing monomer is 0.1 to 5% by weight, preferably 0.2 to 4.4% in 100% by weight of the acrylic polymer (A). It is copolymerized in an amount of 8% by weight, more preferably 0.4 to 4.5% by weight. (a-3) When the nitrogen-containing monomer is more than 5% by weight, the crosslinking density becomes high and the pressure-sensitive adhesive of the present invention cannot maintain a soft structure. On the other hand, if the amount is less than 0.1% by weight, a crosslinked structure cannot be effectively formed, the water resistance is lowered, the strength required for the crosslinked sheet is not exhibited, and the amount of deviation as a result of the micro creep test is large. Too much. In addition, since the strength required for the adhesive tape is not expressed, curl deformation (warp deformation) generated in a laminate of an electrode such as ITO and the adhesive tape increases.

  Furthermore, the acrylic polymer (A) of the present invention comprises the above (a-1) alkoxyalkyl (meth) acrylate and / or alkoxypolyalkylene glycol (meth) acrylate, (a-2) a hydroxyl group-containing monomer and (a-3) In addition to the nitrogen-containing monomer, (a-4) an alkyl (meth) acrylate may be copolymerized.

  Here, examples of the (a-4) alkyl (meth) acrylate forming the acrylic polymer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) Acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) Mention may be made of acrylates, octyl (meth) acrylates, nonyl (meth) acrylates, decyl (meth) acrylates, undeca (meth) acrylates and dideca (meth) acrylates. These (meth) acrylates can be used alone or in combination. Among these, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methyl (meth) acrylate, and iso-butyl (meth) acrylate are preferably used.

  In the acrylic polymer of the present invention, the (a-4) alkyl (meth) acrylate is 0 to 49.8% by weight, preferably 0 to 49.3% by weight, in 100% by weight of the acrylic polymer (A). More preferably, it is copolymerized in an amount of 0 to 48.6% by weight. When (a-4) alkyl (meth) acrylate is more than 48.9% by weight, (a-1) alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate is copolymerized as the main monomer. The working effect will be lost.

The acrylic polymer (A) that forms the adhesive tape for conductive film of the present invention comprises the following components (a-1) to (a-4)
(a-1) alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) a hydroxyl group-containing monomer,
(a-3) Nitrogen-containing monomer and, if necessary
(a-4) A polymer obtained by copolymerizing a predetermined amount of alkyl (meth) acrylate, but other monomers may be copolymerized within a range that does not impair the properties of the acrylic polymer (A). .

  Examples of other monomers that can be copolymerized here include vinyl acetate; (meth) acrylonitrile; cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate; styrene, methylstyrene, dimethylstyrene, and trimethylstyrene. Styrene, such as alkyl styrene such as propyl styrene, butyl styrene, hexyl styrene, heptyl styrene and octyl styrene, fluoro styrene, chloro styrene, bromo styrene, dibromo styrene, iodo styrene, nitro styrene, acetyl styrene and methoxy styrene A mer; glycidyl (meth) acrylate or the like can be used in a range that does not impair the effects of the present application, preferably 0 to 5% by weight.

  The acrylic polymer (A) used in the present invention has substantially no acidic group. Here, having substantially no acidic group means that a monomer having an acidic group is not added intentionally at the time of copolymerization, and it is usually 0.5 mgKOH / g in terms of the acid value of the resulting polymer. It is as follows. Examples of the monomer having an acidic group include a monomer having a carboxyl group such as (meth) acrylic acid, maleic acid, and itaconic acid, a monomer having a phosphoric acid group, and a monomer having a sulfuric acid group. In the present invention, the acrylic polymer (A) is not copolymerized with the above acidic group-containing monomer. Since the acidic group-containing monomer is not copolymerized in this way, the acrylic polymer (A) of the present invention does not corrode even if it is in direct contact with a wiring made of a metal or metal oxide. Even if the wiring contacts the pressure-sensitive adhesive forming the pressure-sensitive adhesive tape, the resistance value of the wiring is not changed over a long period of time.

  Furthermore, the acrylic polymer (A) used in the present invention has a weight average molecular weight of 50,000 or more and less than 400,000, preferably 200,000 to 380,000. By using the acrylic polymer (A) having such a weight average molecular weight (Mw), it has excellent resistance to moisture and heat, which has little fluctuation in haze and good foamability against glass, and excellent step-following performance. In addition, there is an effect that curling hardly occurs in the laminate.

  In the present invention, when the acrylic polymer (A) as described above is produced, the glass transition temperature (Tg) obtained by the Fox formula of the acrylic polymer obtained is usually −70 ° C. to 0 ° C., preferably The monomer is selected to be within the range of -70 ° C to -30 ° C. By using the acrylic polymer (A) having such a glass transition temperature (Tg), a pressure-sensitive adhesive having excellent adhesive strength at room temperature can be obtained.

  The pressure-sensitive adhesive forming the pressure-sensitive adhesive tape of the present invention contains a low molecular weight (meth) acrylic polymer having a hydrogen-bonding functional group and having substantially no acidic group and a weight average molecular weight of less than 100,000. May be.

The low molecular weight (meth) acrylic polymer that can be used in the present invention is usually a copolymer of a hydrogen-bonding functional group-containing monomer and another monomer.
As the hydrogen-bonding functional group-containing monomer that forms this low molecular weight (meth) acrylic polymer, the nitrogen-containing monomer (a-3) described above is usually used.

  Examples of other monomers used here include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate , Iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl Aliphatic (meth) acrylates such as (meth) acrylate, decyl (meth) acrylate, undeca (meth) acrylate, dideca (meth) acrylate and the like; alicyclic rings such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate Genus (meth) acrylate; benzyl (meth) acrylate, Aromatic (meth) acrylates such as nyl (meth) acrylate; furthermore, styrene, methyl styrene, dimethyl styrene, trimethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, octyl styrene and other alkyl styrene, fluoro styrene Styrene monomers such as chlorostyrene, bromostyrene, dibromostyrene, iodinated styrene, nitrostyrene, acetylstyrene and methoxystyrene; glycidyl (meth) acrylate, vinyl acetate, acrylonitrile and the like. In the present invention, methyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate and the like can be preferably used. These monomers can be used alone or in combination.

  In the low molecular weight (meth) acrylic polymer that can be used in the present invention, the hydrogen-bonding functional group-containing monomer and the other monomer are usually in a weight ratio of 0.1-20: 99.9-80, preferably Is copolymerized in a weight ratio of 0.5 to 15; 99.5 to 85.

  The low molecular weight (meth) acrylic polymer used in the present invention has a weight average molecular weight (Mw) of less than 100,000, preferably 5,000 or more and less than 50,000. When used with the above acrylic polymer (A), the low molecular weight (meth) acrylic polymer having such a weight average molecular weight (Mw) acts like a pseudo-crosslinking agent and has good cohesive force and step difference. Follow-up is expressed.

  The low molecular weight (meth) acrylic polymer that can be used in the present invention also has substantially no acidic group. Here, having substantially no acidic group has the same meaning as in the acrylic monomer (A) described above. Thus, since the low molecular weight (meth) acrylic polymer used in the present invention is not copolymerized with an acidic group-containing monomer, the low molecular weight (meth) acrylic polymer of the present invention is made of a metal or metal oxide. Even if the wiring is in direct contact with the wiring, it does not corrode, and the pressure-sensitive adhesive of the present invention can be imparted with the characteristic that the resistance value of the wiring is not changed over a long period of time.

  In the present invention, when producing the low molecular weight (meth) acrylic polymer as described above, the glass transition temperature (Tg) obtained by the Fox formula of the low molecular weight (meth) acrylic polymer obtained is usually 50 ° C. Monomers are selected to be in the range of ~ 110 ° C, preferably 60 ° C to 100 ° C. By using a low molecular weight (meth) acrylic polymer having such a glass transition temperature (Tg), a pressure-sensitive adhesive having excellent adhesive strength at room temperature can be obtained.

  When the acrylic polymer (A) and the low molecular weight (meth) acrylic polymer are used, the weight average molecular weight of the acrylic polymer (A) is as follows. It has a relationship that it is always larger than the weight average molecular weight of the low molecular weight (meth) acrylic polymer, and the weight average molecular weight of the acrylic polymer (A) and the weight average molecular weight of the low molecular weight (meth) acrylic polymer It is preferable to select the acrylic polymer (A) and the low molecular weight (meth) acrylic polymer so that the difference is in the range of 80,000 to 390,000.

  The acrylic polymer (A) and the low molecular weight (meth) acrylic polymer can be produced by a known method, but are preferably produced by solution polymerization. In the solution polymerization, for example, ethyl acetate, methyl ethyl ketone, toluene, acetone or the like can be used as a polymerization solvent. Specifically, a polymerization solvent and a monomer are charged into a reaction vessel, a polymerization initiator is added in an inert gas atmosphere such as nitrogen gas, and the reaction is performed at a reaction temperature of about 50 to 90 ° C. and allowed to react for 4 to 20 hours.

  Examples of the reaction initiator used for solution polymerization include azo initiators and peroxide initiators. These initiators are usually used in an amount in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the monomer. Moreover, you may add suitably a polymerization initiator, a chain transfer agent, etc. in the said polymerization reaction.

  Under the above conditions, the weight average molecular weight can be prepared using a molecular weight modifier according to known techniques, the type of solvent used, the type and amount of polymerization initiator, reaction time, reaction temperature, etc. It is also possible to adjust by adjusting the reaction conditions.

The pressure-sensitive adhesive forming the pressure-sensitive adhesive tape of the present invention further contains an isocyanate-based crosslinking agent (B).
Examples of the isocyanate-based crosslinking agent (B) used in the present invention include molecules such as tolylene diisocyanate, xylylene diisocyanate, chlorophenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate. A compound having two or more isocyanate groups: a compound obtained by addition reaction with a polyhydric alcohol such as trimethylolpropane or pentaerythritol, an isocyanurate compound, a burette type compound, a known polyether polyol or polyester polyol, Two or more polymers are added in the urethane prepolymer type molecule that has undergone addition reaction with acrylic polyol, polybutadiene polyol, polyisoprene, etc. Mention may be made of compounds having a socyanate group.

  Among these, xylylene diisocyanate and its trimethylolpropane adduct are preferable in that it can improve conformability to the adherend and reduce entrainment of bubbles during bonding, and can suppress outgassing at high temperatures, In addition, hexamethylene diisocyanate, its trimethylolpropane adduct, and isocyanurate derivatives are preferable in that the step following property of the attached surface can be improved and the heat-resistant foaming property can be improved.

Such isocyanate-based crosslinking agents (B) can be used alone or in combination.
By blending the isocyanate-based crosslinking agent (B) in this way, the cohesive force of the pressure-sensitive adhesive is improved, and even if air bubbles are slightly involved at the time of pasting, expansion of the air bubbles can be suppressed.

  The pressure-sensitive adhesive constituting the pressure-sensitive adhesive tape of the present invention is 0.01 to 3 parts by weight of the isocyanate-based crosslinking agent (B) with respect to 100 parts by weight of the acrylic polymer (A) and the acrylic polymer (A). It is preferably obtained by blending 0.03 to 2 parts by weight. Thus, by using an isocyanate type crosslinking agent, the amount of fine crepes can be made within the range specified in the present invention.

  The pressure-sensitive adhesive constituting the pressure-sensitive adhesive tape of the present invention includes an antioxidant, a light stabilizer, a metal corrosion inhibitor, a tackifier, a plasticizer, and an antistatic agent as long as the effects of the pressure-sensitive adhesive of the present invention are not impaired. Further, a crosslinking accelerator, a reworking agent and the like can be blended.

  The pressure-sensitive adhesive thus obtained can be used for bonding various members by coating and drying after dilution to an appropriate concentration, in the same manner as known pressure-sensitive adhesives. The coating solution containing the acrylic polymer (A) and isocyanate crosslinking agent (B) used in the present invention in the solvent has a low weight average molecular weight (Mw) of the acrylic polymer (A), so that ethyl acetate, methyl ethyl ketone The concentration of non-volatile components can be adjusted to a desired concentration using a solvent such as acetone or toluene. Therefore, by using the pressure-sensitive adhesive constituting the pressure-sensitive adhesive tape of the present invention, the thickness of the pressure-sensitive adhesive after coating can be easily set to a desired thickness. In particular, the pressure-sensitive adhesive of the present invention can easily prepare a solution having a high nonvolatile content, and for example, the nonvolatile content can be adjusted within a range of 10 to 70%, preferably 20 to 60%. A pressure-sensitive adhesive layer having a desired thickness can be formed with a small number of coatings. Further, by using a solution having a high nonvolatile content as described above, the leveling property of the coating film after coating and drying is improved, and the drying time is shortened and the workability is improved. Furthermore, since the amount of volatile solvent is small, the burden on the environment is also reduced.

  Utilizing such characteristics, the pressure-sensitive adhesive tape for conductive film of the present invention is coated with the above pressure-sensitive adhesive in a dry thickness of 10 to 1000 μm, preferably 25 to 500 μm. It is obtained by curing after removing the solvent.

  This adhesive sheet for conductive films is usually a support (for example, release-treated PET) whose surface is treated with a coating solution of an adhesive whose non-volatile content is adjusted to 10 to 70%, preferably 20 to 60%. Etc.) on the surface of the pressure-sensitive adhesive layer formed by applying a dry thickness within the range of 10 to 1000 μm, preferably 25 to 500 μm, and removing the solvent. It is obtained by sticking a cover film whose surface has been subjected to a peeling treatment, and usually curing at a temperature of 0 to 50 ° C. for 1 to 10 days. The adhesive tape for conductive film of the present invention is obtained by applying the coating liquid onto the support (1) peeled as described above, removing the solvent, and placing another support (2) on the coated surface. It can be manufactured by curing. In this way, the coating liquid is applied to one surface of the support (1), and after removing the solvent, the support (2) is placed on the coating surface and cured to produce the adhesive tape for the conductive film of the present invention. Therefore, a support is not contained in the vicinity of the inside of this pressure-sensitive adhesive tape for conductive films, and is a double-sided adhesive pressure-sensitive adhesive tape without a support. However, the adhesive tape for conductive films of the present invention may be a three-layered adhesive tape in which an adhesive layer is formed on both sides of a support.

  Thus, the gel fraction of the adhesive layer of the adhesive tape for electrically conductive films obtained is normally 0-30%, Preferably it exists in the range of 0-25%, and shows a comparatively low value. That is, in the present invention, since the amount of the isocyanate-based crosslinking agent used is small, a crosslinked structure may be formed between several molecules. When the number of polymer molecules involved in the crosslinked structure is small in this way, May be dissolved in a solvent and not measured as a gel fraction. In the present invention, the gel fraction may be 0% by weight despite the use of an isocyanate-based crosslinking agent. Thus, since the adhesive which comprises the adhesive tape of this invention uses a small amount of isocyanate type crosslinking agents (B), it can form a soft adhesive.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive tape of the present invention is soft, and the value obtained by the micro creep test shown below is in the range of 7 to 9 mm.
As shown in FIG. 7, this micro creep test is a strip test in which an adhesive is applied to one surface of a 100 μm thick polyethylene terephthalate (PET) film with a dry thickness of 25 μm and cut to a width of 10 mm. It is measured using a strip. In this micro creep test, the adherend is a glass substrate, and the strip-shaped test piece is adhered to the surface of the glass substrate so that the adhesion area is 10 mm × 10 mm. A 800 g load is continuously applied at 23 ° C. for 20 minutes to the end of the strip-shaped test piece adhered in this manner and not bonded to the glass substrate. The deviation width between the strip-shaped test piece and the glass substrate after 20 minutes is the value of the micro creep test.

  The harder the adhesive, the smaller the value of this micro creep test, and the strip-shaped test piece falls from the glass substrate if the adhesive is too soft, such as the necessary cross-linked structure is not formed. In this invention, the value calculated | required by this micro creep test exists in the range of 7-9 mm, and it has a required intensity | strength although an adhesive is soft. For this reason, when adhered to an electrode such as ITO, it adheres well to the electrode, and even if a dimensional change occurs in the adhesive tape base material, etc., this dimensional change can be absorbed in the adhesive tape. The laminate including the pressure-sensitive adhesive tape has a characteristic that warp deformation (curl) hardly occurs. Furthermore, since the result of the micro creep test of the adhesive measured for the adhesive shows the above values and the adhesive is soft, the form followability to the frame printing part formed on the edge of the touch panel is very high. It is excellent, and there is an effect that bubbles are not generated in the frame printing portion.

  Thus, although the pressure-sensitive adhesive tape of the present invention is soft as described above, the pressure-sensitive adhesive of the present invention basically comprises (a-1) alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol. (Meth) acrylate, (a-2) hydroxyl group-containing monomer, (a-3) nitrogen-containing monomer and, if necessary, (a-4) a monomer containing alkyl (meth) acrylate, copolymerized with an acidic group Is formed from an acrylic polymer (A) having an average weight average molecular weight of 50,000 or more and less than 400,000 and an isocyanate compound (B), and changes in electrode resistance such as haze change, glass foaming, and ITO And the like have good characteristics secured by the acrylic polymer (A) and the isocyanate compound (B).

The pressure-sensitive adhesive tape thus obtained can be attached to various members, and is particularly suitable for attaching a laminate for a touch panel in which different types of members are attached.
As shown in FIGS. 1 and 2, the touch panel unit includes a resistive touch panel unit (see FIG. 1) and a capacitive touch panel unit (see FIG. 2).

FIG. 1 shows an example of a resistive film type touch panel unit 10-1.
As shown in FIG. 1, the resistive touch panel unit 10-1 bonds the upper stacked body 11-1 and the lower stacked body 13-1 so that the gap 34 is formed by the bonding agent 30. A spacer 32 is disposed in the gap 34 in order to effectively secure the gap width.

  In the upper laminate 11-1, a transparent conductive film 27-1 made of metal or metal oxide is disposed facing the gap 34. This transparent conductive film 27-1 is formed of a conductive material having transparency such as ITO (indium tin oxide), ATO (antimony tin oxide) tin oxide, and is usually made of polyethylene terephthalate (PET) as shown in FIG. ), An upper electrode support 25-1 made of a transparent member such as polymethyl methacrylate (PMMA) or glass.

  A surface support 21-1 is disposed on the outermost surface of the upper laminate 11-1, and this surface support 21-1 is usually a transparent member such as highly transparent glass or polyethylene terephthalate (PET). , Transparent plastic films or plastic plates such as polymethyl methacrylate (PMMA) and cycloolefin polymer (COP).

In order to adhere the surface support 21-1 and the upper electrode support 25-1, an adhesive layer 23-1 made of the adhesive of the present invention is formed.
Similarly, the lower laminated body 13-1 is formed with a transparent conductive film 27-2 made of a metal or a metal oxide so as to face the gap 34. The transparent conductive film 27-2 includes ITO, ATO, A lower electrode made of a transparent conductive material such as tin oxide and usually made of a transparent film such as polyethylene terephthalate (PET) or polymethyl methacrylate (PMMA) or a transparent member such as glass as shown in FIG. It is formed on the surface of the support 25-2.

  A deep surface support 21-2 is formed at the deepest portion of the lower laminate 13-1 so as to face the surface of the flat panel display (FPD). The deep surface support 21-2 is made of glass. Such a transparent member, or a transparent plastic film such as polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) or cyclopolyolefin polymer (COP), or a highly transparent member such as a plastic plate is used.

In the lower laminate 13-1, an adhesive layer 23-2 made of the adhesive tape for conductive film of the present invention is formed in order to bond the deep surface support 21-2 and the lower electrode support 25-2. ing.
Moreover, the adhesive tape for electrically conductive films of this invention may be used as the bonding agent 30. FIG.

  The transparent conductive films 27-1 and 27-2 are formed with a circuit, and by applying pressure from above the surface support 21-1 with a finger or the like, the gap 34 where the pressure is applied disappears. Then, the transparent conductive films 27-1 and 27-2 are in contact with each other to be energized to detect the pressurized portion.

  In the resistive film type touch panel unit 10-1, the thickness of the surface support 21-1 is usually 25 to 2000 μm, and the thickness of the upper transparent electrode film 27-1 is usually 10 to 100 nm. The thickness of the body 25-1 is usually 25 to 2000 μm. As described above, the thickness of the pressure-sensitive adhesive layer 23-1 for laminating them is in the range of 10 to 1000 μm, preferably in the range of 25 to 500 μm.

  Similarly, in the resistive film type touch panel unit, the thickness of the deep support 21-2 is usually 25 to 2000 μm, and the thickness of the lower transparent electrode film 27-2 is usually 10 to 100 nm. The thickness of the body 25-2 is usually 25 to 2000 μm. As described above, the thickness of the pressure-sensitive adhesive layer 23-2 on which these are laminated is in the range of 10 to 1000 μm, preferably in the range of 25 to 500 μm.

Further, in the resistive film type touch panel unit 10-1, the width of the gap formed at the center is usually in the range of 1 to 2000 μm.
On the other hand, the capacitive touch panel unit 10-2 generally has a central support made of a highly transparent member such as glass, polycarbonate (PC), polyethylene terephthalate (PET), cycloolefin polymer (COP), polymethyl methacrylate, and the like. The upper laminate 15-1 and the lower laminate 15-2 are often arranged with the body 60 in between.

  In the upper laminate 15-1 of the capacitive touch panel 10-2, a transparent conductive film 57-1 is disposed in contact with the central support 60, and the outermost surface is a cover glass or polyethylene terephthalate (PET). A surface support 51-1 made of a light transmitting member such as polymethyl methacrylate (PMMA) or cyclopolyolefin polymer (COP) is disposed. The pressure-sensitive adhesive layer 53-1 made of the pressure-sensitive adhesive tape of the present invention is disposed so as to bond the transparent conductive film 57-1 and the surface support 51-1. It is in direct contact with the membrane 57-1.

  On the other hand, in the upper laminate 15-2 in the capacitive touch panel unit 10-2, a transparent conductive film 57-2 is disposed in contact with the central support 60, and in the deepest part, a cover glass or polyethylene is provided. A surface support 51-2 made of a light transmitting member such as terephthalate (PET), polymethyl methacrylate (PMMA), cyclopolyolefin polymer (COP) is disposed. The pressure-sensitive adhesive layer 53-2 made of the pressure-sensitive adhesive tape of the present invention is disposed so as to bond the transparent conductive film 57-2 and the deepest surface support 51-2. In direct contact with the transparent conductive film 57-2.

In the capacitive touch panel unit 10-2, the deepest surface support 51-2 is disposed so as to face the flat panel display.
In the capacitive touch panel unit 10-2, the thickness of the upper laminate 51-1 is usually 175 to 3000 μm, and the thickness of the upper transparent electrode film 57-1 is usually 10 to 100 nm. The thickness of the pressure-sensitive adhesive layer 53-1 to be bonded is 10 to 1000 μm as described above. In the lower laminate 15-2, the thickness of the lower transparent electrode film 57-2 is usually 10 to 100 nm, and the thickness of the deepest surface support 51-2 is usually 25 to 2000 μm. As described above, the thickness of the pressure-sensitive adhesive layer for adhering is 10 to 1000 μm. Further, the thickness of the central support 60 between the upper laminate 15-1 and the lower laminate 15-2 is usually in the range of 25 to 2000 μm.

  The upper electrode film 51-1 and the lower electrode film 51-2 form a circuit. Further, in the capacitive touch panel unit 10-2 shown in FIG. 2, the upper electrode film 10-2 is formed as two series of circuits provided independently in the X-axis direction and the Y-axis direction, respectively. The laminated body 15-2 can also be omitted.

In the capacitive touch panel, the contact position is detected by reading the change in the capacitance of the contact portion caused by the finger touching the surface of the touch panel unit 10-2.
For the touch panel unit as described above, for example, frame printing is performed on the surface of the edge surface support 51-1 that is in contact with the adhesive shown by A in FIG. This frame printing portion is shown in an enlarged manner in FIG. In FIG. 3, the frame printing portion is indicated by the number 62. The thickness (t ₀ ) of the frame printing portion 62 is normally 10 to 50 μm, and its cross section is formed in a substantially rectangular shape. Since the pressure-sensitive adhesive layer 53-1 is formed by sticking the above-mentioned pressure-sensitive adhesive tape of the present invention to the surface support 51-1, the pressure-sensitive adhesive layer formed on the pressure-sensitive adhesive tape is hard and has poor form following ability. As shown in FIG. 4 (a), the adhesive layer 53-1 is located between the surface support 51-1 and the frame printing portion 62 at the end of the frame printing portion 62 and between the surface support 51-1. A gap 64 that is not in contact with any of the edges is formed. Originally, as shown in FIG. 4 (b), the adhesive layer 53-1 must be in close contact with the edge portions of the surface support 51-1 and the frame printing portion 62 without forming the gap 64.

  However, in the pressure-sensitive adhesive based on a pressure-sensitive adhesive having a weight average molecular weight of 400,000 to 1.6 million as in the past, the shape of the pressure-sensitive adhesive layer cannot be changed due to such a very fine shape change, and the gap 64 is formed. It will be formed.

  The pressure-sensitive adhesive layer 53-1 constituting the laminate for a touch panel of the present invention in which a surface support, a pressure-sensitive adhesive layer, and a transparent electrode film (which may have a support) are laminated has a specific composition as described above. And having a very excellent form following property by crosslinking the acrylic polymer (A) having a weight average molecular weight (Mw) of 50,000 or more and less than 400,000 with an isocyanate crosslinking agent (B), No gap 64 is formed around the frame printing portion 62.

  When the laminate for a touch panel of the present invention uses a member that easily generates outgas such as polycarbonate (PC) as the support 51-2 as shown in FIG. When the test is performed, outgas from the support may be generated, and bubbles 66 may be generated between the support and the pressure-sensitive adhesive layer. Even if a support that does not generate outgas is used, bubbles 68 may be involved when the support and the pressure-sensitive adhesive layer are bonded to each other, and if this bubble grows due to a temperature change, it will cause foaming. The pressure-sensitive adhesive forming the pressure-sensitive adhesive sheet of the present invention has a specific composition, and crosslinks an acrylic polymer (A) having a weight average molecular weight (Mw) of 50,000 or more and less than 400,000 with an isocyanate-based crosslinking agent (B). Therefore, it has a very high cohesive force, and the foaming due to the outgas as described above and the foaming due to the growth of entrained bubbles can be suppressed by the high cohesive force. Therefore, in the laminated body for touch panels of this invention, the above foaming can be hardly observed. However, when polycarbonate (PC), which is likely to generate outer gas, is used, foaming due to outer gas from the polycarbonate (PC) may not be prevented. Therefore, in the present invention, a glass substrate is used as a transparent substrate in contact with the adhesive tape. Particularly suitable for use.

  Moreover, in the laminated body for touch panels, when a member is left under durability test conditions (60 ° C., 90%), moisture may enter from the support side and the end as shown in FIG. Under high temperature conditions, the infiltrated moisture does not precipitate, but when the temperature decreases, the infiltrated moisture precipitates, forming visible droplets, and the touch panel laminate is whitened. The haze value increases. The pressure-sensitive adhesive layer that forms the laminate for a touch panel of the present invention is dispersed in a pressure-sensitive adhesive layer having a high cohesive force even when moisture enters from the support layer or the end by having a specific composition. Since no visible droplets are formed, the haze value is hardly increased due to the whitening phenomenon.

  Further, since the pressure-sensitive adhesive forming the pressure-sensitive adhesive tape of the present invention does not substantially contain acidic groups, even if this pressure-sensitive adhesive directly contacts a transparent conductive film made of metal or metal oxide, the transparent electrode film The change in the resistance value is about 10% at the maximum, and this amount of change is an amount that does not cause any problem in driving the touch panel.

  In particular, since the pressure-sensitive adhesive constituting the conductive film pressure-sensitive adhesive tape of the present invention is soft, the conductive film pressure-sensitive adhesive tape is cured when a laminate of an electrode such as ITO and the conductive film pressure-sensitive adhesive tape is formed. Since the pressure-sensitive adhesive tape itself absorbs internal stress generated by the dimensional change, the laminate of the electrode and the pressure-sensitive adhesive tape has a characteristic that warp deformation (curl) hardly occurs.

In addition, in this invention, the curl of the laminated body of an electrode and the adhesive tape for electrically conductive films is evaluated based on the value measured by the method shown in FIG.
As described above, the laminate for a touch panel of the present invention comprises a main alkyl polymer (A) having a specific composition as an adhesive constituting the adhesive tape and having a weight average molecular weight of 50,000 or more and less than 400,000, and an isocyanate crosslinking agent ( The support and the transparent conductive film are adhered to each other using an adhesive tape having B), and has excellent shape followability, and voids are formed in the frame print portion formed on the edge. In addition, foaming due to entrainment can be suppressed, and water is not precipitated, so that the pressure-sensitive adhesive layer is not whitened and the haze value is not increased.

EXAMPLES Next, the present invention will be described in more detail with reference to examples of the present invention, but the present invention is not limited thereto.
The weight average molecular weight, gel fraction, non-volatile content, wet heat whitening property, heat-resistant foaming property, ITO corrosion property, coating property, workability, step following property, and adhesive strength were measured by the following methods.
〔Measuring method〕
<Molecular weight>
The weight average molecular weight (Mw) in terms of standard polystyrene was determined using gel permeation chromatography (GPC).
Measuring condition apparatus: HLC-8120GPC (manufactured by Tosoh Corporation)
Column: TSK-GEL HXL-H (guard column, manufactured by Tosoh Corporation)
TSK-GEL 7000HXL (manufactured by Tosoh Corporation)
TSK-GEL GMHXL (manufactured by Tosoh Corporation)
TSK-GEL GMHXL (manufactured by Tosoh Corporation)
TSK-GEL G2500HXL (manufactured by Tosoh Corporation)
Sample concentration: diluted with tetrahydrofuran to 1.0 mg / cm ³ Mobile phase solvent: tetrahydrofuran Flow rate: 1.0 cm ³ / min
Column temperature: 40 ° C
<Gel fraction>
About 0.1 g of adhesive after aging at 23 ° C. for 7 days was collected in a sampling bottle, 30 cc of ethyl acetate was added and shaken for 4 hours, and then the contents of this sample bottle were filtered through a 200 mesh stainless steel wire mesh. The residue on the wire mesh was dried at 100 ° C. for 2 hours, and the dry weight was measured.

＜ヘイズ＞
得られた粘着テープの片面の剥離シートを剥がして、厚み３８μｍポリエチレンテレフタレートフィルムを貼り合わせ、５０mm×５０mmのサイズに裁断した。次いで、もう一方の剥離フィルムを剥がして、厚み２mmＰＣ板に貼り合わせ、５０℃、５ａｔｍのオートクレーブで２０分間処理した後、１時間静置して試験片を作成した。

<Haze>
The release sheet on one side of the obtained pressure-sensitive adhesive tape was peeled off, and a 38 μm-thick polyethylene terephthalate film was bonded together and cut into a size of 50 mm × 50 mm. Next, the other release film was peeled off, bonded to a 2 mm thick PC plate, treated in an autoclave at 50 ° C. and 5 atm for 20 minutes, and then allowed to stand for 1 hour to prepare a test piece.

  After measuring the haze before the endurance test of the prepared test piece, it was allowed to stand at 60 ° C., 90% environment, 85 ° C., 85% environment. After 500 hours, the test piece was taken out and allowed to stand at room temperature for 1 hour, and then the haze was measured to determine the difference from the haze before the durability test.

For the measurement of haze, MH-150 (manufactured by Murakami Color Research Laboratory Co., Ltd.) was used.
<Foaming>
The release sheet on one side of the obtained adhesive tape was peeled off, and a 38 μm thick polyethylene terephthalate film on which ITO was vapor-deposited was bonded and cut into a size of 50 mm × 50 mm. Next, the other release film was peeled off, bonded to a 2 mm thick glass substrate, treated in an autoclave at 50 ° C. and 5 atm for 20 minutes, and then allowed to stand for 1 hour to prepare a test piece.

After measuring the haze for the durability test of the prepared test piece, it was allowed to stand at 60 ° C., 90% environment, 85 ° C., dry environment, 85 ° C., 85% environment. The test piece after the elapse of 500 hours was taken out and allowed to stand at room temperature for 1 hour, and then the degree of foaming was visually confirmed.
Evaluation criteria are as follows (Evaluation) (Contents)
○: No bubbles can be visually confirmed in the adhesive layer.
X: Large bubbles can be confirmed. Alternatively, the pressure-sensitive adhesive layer is floating from the substrate or the adherend.

<ITO resistance change rate>
In the foaming test, the resistance value before the foaming test was measured in advance, and then the resistance value of the test piece placed in an environment of 85 ° C. and 85% for 500 hours was measured to determine the rate of change of the resistance value.

The resistance value was measured using a tester (manufactured by Sanwa Denki Keiki Co., Ltd., Digital Multimeter PC510).
<Step following capability>
The PET film on which one side of the obtained pressure-sensitive adhesive tape for conductive film was peeled was peeled off, and a 25 μm PET film was bonded together and cut into 50 mm × 50 mm to prepare test pieces.

Next, the PET film cut to 25 mm × 25 mm is placed on the glass plate, the peeled PET film on the other side of the prepared test piece is peeled off, and the PET film on the glass plate is pasted so as to cover the entire surface. The sample was allowed to stand in an 80 ° C. environment for 500 hours and then allowed to stand at room temperature for 1 hour, and the appearance of the step portion was visually observed.
(Evaluation) (Content)
○: Bubbles cannot be visually confirmed in the stepped portion.
X: Although it is a practical use grade, a bubble can be confirmed clearly visually at a sticking step part.

<Small creep displacement>
A strip-shaped test piece was prepared by applying a pressure-sensitive adhesive to a thickness of 25 μm on one surface of a 100 μm thick polyethylene terephthalate film and cutting it to a width of 10 mm. One end of the strip-shaped test piece was attached to the surface of the glass substrate so that the adhesion area was 10 mm × 10 mm. Next, a load of 800 g is applied to the end of the strip-shaped test piece that is not bonded to the glass substrate, and the deviation width of the strip-shaped test piece with respect to the glass substrate is measured at 23 ° C. after 20 minutes, The value of the micro creep test was used.

<ITO curl properties>
The laminate with the adhesive tape attached to ITO (electrode) was cured at 70 ° C. for 3 days, and placed on the substrate so that the ITO (electrode) was the upper surface and the adhesive tape was the lower surface, as shown in FIG. The distance from the base surface to the top surface of the laminate (the amount of warpage and the amount of curl) was measured. Based on this measured value, ITO curl properties were evaluated according to the following criteria.
○: The distance from the base surface to the top surface of the laminate is 5 mm or less.
X: The distance from a base surface to the upper surface of a laminated body exceeds 5 mm.

[Example 1]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 1 (polymer 1) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 1 is -48 degreeC.

  To the polymer 1 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate-based curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of polymer 1. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

[Example 2]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of ethoxydiethylene glycol acrylate (ECA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 2 (polymer 2) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 2 is -57 degreeC.

  To the polymer 2 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of polymer 2. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.
Example 3
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of dimethylaminoethyl acrylate (DMAEA), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain an acrylic polymer 3 (polymer 3) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 3 is -48 degreeC.

  To the polymer 3 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 3. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 4
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of n-vinylpyrrolidone (n-VP), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 4 (polymer 4) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 4 is -48 degreeC.

  To the polymer 4 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 4. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 5
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acryloylmorpholine (ACMO), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 5 (polymer 5) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 5 is -48 degreeC.

  To the polymer 5 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 5. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained adhesive tape for viscous conductive film, the gel fraction, haze change, glass foaming resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 6
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 91 parts by weight of methoxyethyl acrylate (MEA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA), 2 parts by weight of acrylamide (AM) Then, 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 6 (polymer 6) having a weight average molecular weight of 330,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 6 is -50 degreeC.

  To the polymer 6 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 6. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 7
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 37.5 parts by weight of butyl acrylate (BA), 2-hydroxyethyl acrylate (2-HEA) 7 parts by weight, 0.5 part by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 7 (main polymer 7) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained main polymer is -49 degreeC.

  To the polymer 7 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 7. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 8
A reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen inlet tube was charged with 55 parts by weight of methoxyethyl acrylate (MEA), 34 parts by weight of butyl acrylate (BA), 2-hydroxyethyl acrylate (2-HEA) 7 and 4 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 8 (polymer 8) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 8 is -45 degreeC.

  To the polymer 8 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 8. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 9
In a reaction apparatus equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 43 parts by weight of butyl acrylate (BA), 7 parts by weight of 4-hydroxybutyl acrylate (4-HBA) Part, 2 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were added, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 9 (polymer 9) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 9 is -52 degreeC.

  To the polymer 9 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of polymer 9. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 10
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 41 parts by weight of butyl acrylate (BA), 2 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Part, 2 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were added, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 10 (polymer 10) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 10 is -49 degreeC.

  To the polymer 10 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 10. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 11
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 33 parts by weight of butyl acrylate (BA), 10 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Part, 2 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were added, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 11 (polymer 11) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 11 is -46 degreeC.

  To the polymer 11 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 11. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

Example 12
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Part, 2 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were added, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 12 (polymer 12) having a weight average molecular weight of 90,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 12 is -48 degreeC.

  To the polymer 12 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.3 part by weight with respect to 100 parts by weight of the solid content of the polymer 12. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

[Production Example 13]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Part, 2 parts by weight of acrylamide, 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were added, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 13 (polymer 13) having a weight average molecular weight of 300,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 13 is -48 degreeC.

  To the polymer 13 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.05 part by weight with respect to 100 parts by weight of the solid content of the polymer 13. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape for conductive film.

  Using the obtained pressure-sensitive adhesive tape for conductive film, the gel fraction, haze change, glass foam resistance, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 1.

[Comparative Example 1]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 31 parts by weight of methoxyethyl acrylate (MEA), 60 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 14 (polymer 14) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 14 is -49 degreeC.

  To the polymer 14 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 14. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 2]
A reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen introduction tube was charged with 31 parts by weight of methoxyethyl acrylate (MEA), 60 parts by weight of 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2- HEA), 7 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 15 (polymer 15) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 15 is -59 degreeC.

  To the polymer 15 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals, Inc.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 15. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 3]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen introduction tube, 91 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA), 2 parts by weight of acrylamide (AM) and 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 16 (polymer 16) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 16 is -50 degreeC.

  To the polymer 16 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 16. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the adhesive surface and aged at 23 ° C. for 7 days to obtain an adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 4]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen introduction tube, 91 parts by weight of 2-ethylhexyl acrylate (2-EHA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA), acrylamide (AM) 2 parts by weight, 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 17 (polymer 17) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 17 is -65 degreeC.

  To the polymer 17 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 17. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 5]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 38 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 18 (polymer 18) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 18 is -50 degreeC.

  To the polymer 18 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 18. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 6]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 32 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 6 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were heated to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 19 (polymer 19) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 19 is -43 degreeC.

  To the polymer 19 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 19. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 7]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Part, 2 parts by weight of acrylamide (AM) and 120 parts by weight of ethyl acetate (EtAc) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 20 (polymer 20) having a weight average molecular weight of 600,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 20 is -48 degreeC.

  To the polymer 20 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals) as an isocyanate-based curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 20. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 8]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 35 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 1 part by weight of acrylic acid (AA), 100 parts by weight of ethyl acetate (EtAc), and 20 parts by weight of methyl ethyl ketone (MEK) were heated to 70 ° C. while introducing nitrogen gas. .

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 21 (polymer 21) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 21 is -47 degreeC.

  To the polymer 21 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.1 part by weight with respect to 100 parts by weight of the solid content of the polymer 21. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 9]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 22 (polymer 22) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 22 is -48 degreeC.

  To the polymer 22 obtained as described above, Takenate D-110N (manufactured by Mitsui Chemicals Co., Ltd.) as an isocyanate curing agent was added at a ratio of 0.4 part by weight relative to 100 parts by weight of the solid content of the polymer 22. Thus, a pressure-sensitive adhesive composition was obtained (solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

[Comparative Example 10]
In a reactor equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen introduction tube, 55 parts by weight of methoxyethyl acrylate (MEA), 36 parts by weight of butyl acrylate (BA), 7 parts by weight of 2-hydroxyethyl acrylate (2-HEA) Parts, 2 parts by weight of acrylamide (AM), 100 parts by weight of ethyl acetate (EtAc) and 20 parts by weight of methyl ethyl ketone (MEK) were charged, and the temperature was raised to 70 ° C. while introducing nitrogen gas.

Subsequently, 0.2 part by weight of azobisisobutyronitrile (AIBN) was added, and a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate (EtAc) and adjusted to a solid content concentration of 30% to obtain acrylic polymer 23 (polymer 23) having a weight average molecular weight of 350,000. The glass transition temperature (Tg) calculated | required by the formula of Fox about the obtained polymer 23 is -48 degreeC.

  A pressure-sensitive adhesive composition was obtained without blending Takenate D-110N (manufactured by Mitsui Chemicals, Inc.), which is an isocyanate curing agent, with the polymer 23 obtained as described above. (Solid content: 30% by weight).

  The obtained pressure-sensitive adhesive composition was applied onto a release-treated polyethylene terephthalate (PET) film to a dry thickness of 50 μm, dried at 80 ° C. for 2 minutes to remove the solvent, The release-treated PET film was bonded to the pressure-sensitive adhesive surface and aged at 23 ° C. for 7 days to obtain a pressure-sensitive adhesive tape.

  Using the obtained adhesive tape, the gel fraction, haze change, resistance to glass foaming, step following ability, minute creep displacement, ITO resistance change rate, and resistance to ITO curl were measured. The results are also shown in Table 2.

10-1 ... resistive film type touch panel unit 10-2 ... capacitive touch panel unit 11-1 ... upper laminate 13-1 ... lower laminate 15-1 ... upper part Laminate 15-2 ... Lower laminate 21-1 ... Surface support 21-2 ... Deep surface support 23-1 ... Adhesive layer 23-2 ... Adhesive layer 25 -1 ... Upper electrode support 25-2 ... Lower electrode support 27-1 ... Transparent conductive film 27-2 ... Transparent conductive film 30 ... Bonding agent 32 ... Spacer 34 ... Gap 51-1 ... Surface support 51-2 ... Surface support 53-1 ... Adhesive layer 57-1 ... Transparent conductive film 57-2 ... Transparent conductive film 60 ... Center support 62 ... Frame printing part 64 ... Gap 66 ... Bubble 68 ... Bubble

Claims (11)

The following components (a-1) to (a-4)
(a-1) 50-99.8% by weight of alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) hydroxyl group-containing monomer 0.1 to 10% by weight,
(a-3) Nitrogen-containing monomer 0.1 to 5% by weight and
(a-4) Alkyl (meth) acrylate 0 to 49.8% by weight
An acrylic polymer (A) having a weight average molecular weight of substantially 50,000 or more and less than 400,000, which is obtained by copolymerizing a monomer containing
One surface of a polyethylene terephthalate film having a thickness of 100 μm, having a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive having a gel fraction obtained from the isocyanate compound (B) in the range of 0 to 30% by weight A strip-shaped test piece coated with a pressure-sensitive adhesive with a dry thickness of 25 μm and cut to a width of 10 mm was stuck on the surface of the glass substrate so that the adhesion area was 10 mm × 10 mm, and the strip-shaped test piece A value of a minute creep test, which is a deviation width of the strip-shaped test piece with respect to the glass substrate when measured after 20 minutes at 23 ° C. by applying a weight of 800 g to the end not bonded to the glass substrate, is 7 mm to 9 mm. It exists in the range of this, The adhesive tape for electrically conductive films characterized by the above-mentioned.   The pressure-sensitive adhesive tape for conductive film according to claim 1, wherein the acrylic polymer (A) has a glass transition temperature (Tg-1) in the range of -70 ° C to 0 ° C.   The pressure-sensitive adhesive tape for conductive film according to claim 1, wherein the pressure-sensitive adhesive tape for conductive material is a pressure-sensitive adhesive for a capacitive touch panel in direct contact with a metal or metal oxide.   2. The adhesive tape for conductive film according to claim 1, wherein the average thickness of the adhesive layer forming the adhesive tape for conductive film is in the range of 10 to 1000 [mu] m in terms of dry thickness.   2. The adhesive tape for conductive film according to claim 1, wherein the adhesive tape for conductive film is a double-sided adhesive tape, and the double-sided adhesive tape does not have a support near the center in the thickness direction. The following components (a-1) to (a-4)
(a-1) 50-99.8% by weight of alkoxyalkyl (meth) acrylate and / or alkoxy polyalkylene glycol (meth) acrylate,
(a-2) hydroxyl group-containing monomer 0.1 to 10% by weight,
(a-3) Nitrogen-containing monomer 0.1 to 5% by weight and
(a-4) Alkyl (meth) acrylate 0 to 49.8% by weight
An acrylic polymer (A) having a weight average molecular weight of substantially 50,000 or more and less than 400,000, which is obtained by copolymerizing a monomer containing
One surface of a polyethylene terephthalate film having a thickness of 100 μm, having a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive having a gel fraction obtained from the isocyanate compound (B) in the range of 0 to 30% by weight A strip-shaped test piece coated with an adhesive to a thickness of 25 μm and cut to a width of 10 mm was attached to the surface of the glass substrate so that the adhesion area was 10 mm × 10 mm, and the strip-shaped test piece was A value of a minute creep test, which is a deviation width of the strip-shaped test piece with respect to the glass substrate when measured after 20 minutes at 23 ° C. with a weight of 800 g applied to the end not bonded to the glass substrate, is 7 mm to 9 mm. A laminate for a touch panel, wherein an adhesive tape and a transparent electrode layer in a range are laminated.   The laminate for a touch panel according to claim 6, wherein the acrylic polymer (A) has a glass transition temperature (Tg-1) in the range of -70 ° C to 0 ° C.   The laminate for a touch panel according to claim 6, wherein the adhesive tape for conductive film is an adhesive for a capacitive touch panel in direct contact with a metal or a metal oxide.   The laminate for a touch panel according to claim 6, wherein an average thickness of the pressure-sensitive adhesive layer forming the pressure-sensitive adhesive tape for conductive film is in the range of 10 to 1000 µm in terms of an average dry thickness.   The laminate for a touch panel according to claim 6, wherein the adhesive tape for a conductive film is a double-sided adhesive tape, and the double-sided adhesive tape does not have a support in the vicinity of the center in the thickness direction.   The laminate for a touch panel according to claim 6, wherein the laminate for a touch panel has a transparent substrate, and the transparent substrate is a glass substrate.

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