JPH11241056A - Adhesive composition and adhesive sheet prepared therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive compsn. which exhibits a strong tack, exhibiting an improved initial tack, while being excellent in release from a release liner untreated with a silicone by using, as the main component, a condensation polymer having specific polycarbonate structures and specific cyclic or acyclic dioyl or diol structures. SOLUTION: The polycarbonate structure is represented by formula I (wherein R is a 2-20C aliph. hydrocarbon group); the dioyl structure, by formula II (wherein R<1> is a 34C cyclic or acyclic satd. hydrocarbon group); and the diol structure, by formula III (wherein R<2> is a 36C cyclic or acyclic satd. hydrocarbon group. The structure of formula II derives from a hydrogenated dimer acid prepd. by hydrogenating the dimer acid of an 18C unsatd. fatty acid; and the structure of formula III, from a hydrogenated dimer diol prepd. by reducing a hydrogenated dimer acrid. As the release liner, a polyolefin film untreated with a silicone is suitable. This adhesive compsn. can be used not only in the fields of electronic apparatus where the presence of a silicone is avoided but also in high-speed continuous adhesion operations requiring instant adhesion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive composition containing a condensation polymer such as polyester as a main component, and pressure-sensitive adhesive sheets.

[0002]

2. Description of the Related Art As a pressure-sensitive adhesive composition containing a condensation polymer as a main component, for example, Japanese Patent Application Laid-Open No. 9-263747 discloses a pressure-sensitive adhesive composition containing a polyester having a polycarbonate structure as a main component. It has been disclosed. This kind of pressure-sensitive adhesive composition has an advantage that it is basically non-adhesive or low-adhesive (tack-free) at room temperature, and has the advantage that it is difficult to inadvertently adhere to parts other than the intended place. ing.

[0003] The adhesive tape has a release liner attached to the adhesive surface from the viewpoint of protection or handling of the adhesive surface. As the release liner, in the case of an adhesive tape such as an acrylic or rubber type, a plastic film whose surface has been subjected to a silicone treatment is used in order to obtain good release properties. In a pressure-sensitive adhesive tape using a pressure-sensitive adhesive composition containing as a main component, sufficiently good release properties can be obtained even when a release liner made of a polyolefin-based film or the like and not subjected to silicone treatment is used. The release liner without such silicon treatment has no concern about the migration of silicon to the adhesive surface, and can be used without any problem for electronic equipment applications that do not like the presence of silicon. Has advantages.

[0004]

However, known pressure-sensitive adhesive compositions containing a condensation polymer such as polyester having a polycarbonate structure as a main component have the above-mentioned advantages, but require instant adhesion. Applications, such as high-speed continuous bonding work or applications where stress is applied immediately after bonding,
It could not be used due to poor initial tack.

In view of such circumstances, the present invention provides a pressure-sensitive adhesive composition containing a condensation polymer as a main component, which can be used even if a release liner having a large adhesive strength and not subjected to silicone treatment is used. It is an object of the present invention to provide a pressure-sensitive adhesive composition which has excellent releasability and is improved in initial tackiness, and pressure-sensitive adhesive sheets thereof.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies in order to achieve the above-mentioned object, and as a result, polycarbonate as a raw material component for obtaining a condensation polymer such as polyester or polyurethane. With 1 carbon atom such as linoleic acid together with aliphatic diol or dicarboxylic acid having
Hydrogenated dimer acid obtained by hydrogenating the dimer acid of unsaturated fatty acid 8 or hydrogenated dimer geo obtained by reducing the same
With the use of a specific polycarbonate structure,
A condensation polymer having a specific cyclic or acyclic di-oil or diol structure derived from the dimer acid or hydrogenated dimer-diol is obtained. It also shows that a pressure-sensitive adhesive composition exhibiting good peelability even with a release liner not subjected to silicone treatment and having improved initial tackiness was obtained, which led to the completion of the present invention. It is.

That is, the present invention provides a) the following formula (A): (R is a linear or branched aliphatic hydrocarbon group having 2 to 20 carbon atoms), and b) the following formula (B1); (R ¹ is a cyclic or acyclic saturated hydrocarbon group having 34 carbon atoms) or the following formula (B2); -OR ² -O- ... (B2) (R ² is a cyclic or acyclic saturated hydrocarbon group having 36 carbon atoms), and a condensed polymer having at least one of the structures represented by the following formulas: In particular, the structure represented by the formula (B1) is derived from a hydrogenated dimer acid obtained by hydrogenating a dimer acid of an unsaturated fatty acid having 18 carbon atoms. In addition, the pressure-sensitive adhesive composition having the above structure, wherein the structure represented by the formula (B2) is derived from hydrogenated dimer diol obtained by reducing the above hydrogenated dimer acid (claim 2) ) Can be provided.

[0008] The present invention also provides a pressure-sensitive adhesive sheet in the form of a sheet or tape, which has a layer comprising the pressure-sensitive adhesive composition having the above structure on one or both sides of a support. The adhesive sheet according to the present invention (claim 3), in particular, an adhesive sheet (claim 4) having the above-mentioned structure in which a release liner not subjected to silicone treatment is bonded to the adhesive surface. The pressure-sensitive adhesive sheets having the above constitution (claim 5), wherein the release liner not subjected to the silicone treatment is a polyolefin-based film made of polyethylene, polypropylene, ethylene-propylene copolymer, or the like.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The condensation polymer used in the present invention is:
Polycarbonate represented by the above formula (A) as the structure of component a
It has a bone structure, and has a cyclic or acyclic dioil structure represented by the formula (B1) as the structure of the component b, or a cyclic or acyclic structure represented by the formula (B2). The condensation form is not limited as long as it has a structure of at least one of the above-mentioned diol structures, and as long as it has a structure of both the components a and b. The most typical one is polyester, and examples thereof include polyurethane, and a mixture or co-condensate thereof with polyester.

The condensed polymer composed of polyester is used as a raw material component composed of a dicarboxylic acid component and a diol component together with a compound having a polycarbonate structure represented by formula (A) and a compound represented by formula (B1). A compound having a dioil structure represented by the formula (B2), a compound having a diol structure represented by the formula (B2), a dioil structure represented by the formula (B1) and a compound represented by the formula (B2)
By using at least one of the compounds having both the diol structure represented by the above and, if necessary, adding a dicarboxylic acid component or a diol component other than these, and performing an esterification reaction by a conventional method, Obtainable. In the esterification reaction, the diol component and the dicarboxylic acid component are
Although an equimolar reaction is desirable, either of them may be used in excess to promote the esterification reaction.

In the compound having a polycarbonate structure represented by the formula (A), a compound in which R is a linear or branched aliphatic hydrocarbon group having 2 to 20 carbon atoms. , Dicarboxylic acids, and lower alkyl esters thereof. Among them, diol is easily available as a commercial product, and is particularly preferably used. More specifically, polyhexamethylene carbonate carbonate, poly (3-methylpentenecarbonate) diol, poly (2-methyloctane) diol, polypropylene card
Examples include bone diols, mixtures and copolymers thereof.

[0012] Commercially available such diols include, for example, "PLACCEL" manufactured by Daicel Chemical Industries, Ltd.
CD208PL ”,“ PLACCEL CD210P ”
L "," PLACCEL CD220PL "," PLA
CCEL CD208 ”,“ PLACCEL CD21 ”
0 ”,“ PLACCEL CD220 ”,“ PLACC
EL CD208HL "," PLACCEL CD21
0HL "," PLACCEL CD220HL "and the like.

The compound having a dioil structure represented by the formula (B1) is a dicarboxylic acid or a derivative thereof, wherein R ¹ is a cyclic or acyclic saturated hydrocarbon group having 34 carbon atoms. Examples of the dicarboxylic acid include unsaturated fatty acids having 18 carbon atoms (industrially, unsaturated fatty acids containing linoleic acid obtained from fats and oils such as safflower oil, soybean oil, linseed oil, and tall oil). ), That is, hydrogenated dimer acid obtained by hydrogenating a polymerized fatty acid composed of a dimer to a saturated carboxylic acid by an appropriate method. Examples of the derivatives include lower alcohols, diols, and esters with other polyhydric alcohols.

The compound having a diol structure represented by the formula (B2) is a diol or a derivative thereof in which R ² is a cyclic or acyclic saturated hydrocarbon group having 36 carbon atoms. The above diols include hydrogenated dimer diols obtained by reducing both carboxyl groups of the above hydrogenated dimer acid to primary alcohol groups. Examples of the derivatives include esters with lower carboxylic acids, dicarboxylic acids, and other polybasic acids. Compounds having both the dioil structure represented by the formula (B1) and the diol structure represented by the formula (B2) include the hydrogenated dimer acid and the hydrogenated dimer geo- And esters with thiol.

[0015] Other diol components other than these include:
Linear diols such as ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol, decandiol, octadecandiol, etc.
And branched diols. The content of these other diol components is preferably not more than 50% by weight of the diol components. In order to increase the molecular weight of the polyester-based condensation polymer, a small amount of a tri- or higher functional polyol component may be added.

The other dicarboxylic acid component includes a dicarboxylic acid having a molecular skeleton of an aliphatic or alicyclic hydrocarbon group having 2 to 20 carbon atoms. The above-mentioned hydrocarbon group may be linear or branched. Specifically, succinic acid, methyl succinic acid, adipic acid, pimelicic acid, azelaic acid, sebacic acid, 1,12-dodecandioic acid, 1,14-tetradecandioic acid, tetrahydrophthalic acid, these acid anhydrides and lower acids Derivatives such as alkyl esters are exemplified.

The condensation polymer composed of polyurethane uses only the diol component of the above compounds in the same combination as the raw material component, and optionally uses the other diol component as described above. In addition, hexamethylene diisocyanate, diphenylmethane diisocyanate
The compound can be obtained by subjecting a polyisocyanate mainly composed of diisocyanate such as urethan to a urethanization reaction.

In the present invention, a pressure-sensitive adhesive composition having excellent pressure-sensitive adhesive properties can be obtained by crosslinking such a condensation polymer by an appropriate means. Examples of the crosslinking means include a method using a so-called crosslinking agent, in which a compound having a group that reacts with a hydroxyl group or a carboxyl group contained in a condensation polymer such as a polyisocyanate compound, an epoxy compound, or an aziridine compound is added and reacted. . Among the crosslinking agents, polyisocyanate compounds are particularly preferably used.

Examples of the polyisocyanate compound include aliphatic polyisocyanates such as ethylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate, cyclopentylene diisocyanate, and cyclohexyl. Alicyclic isocyanates such as range isocyanate and isophorone diisocyanate, 2,4-tolylene diisocyanate, diphenylmethane diisocyanate
And diisocyanates such as xylene diisocyanate, and isocyanate adducts such as tolylene diisocyanate adduct of hexamethyldiisocyanate and hexamethylene diisocyanate adduct of trimethylolpropane. . These polyisocyanate compounds are used alone or in a mixture of two or more. The amount used is the condensation polymer 10
Usually, it is preferably about 1 to 10 parts by weight with respect to 0 parts by weight.

The pressure-sensitive adhesive composition of the present invention comprises the above-mentioned condensation polymer as a main component, and is usually subjected to a crosslinking treatment as described above. And various additives such as inorganic or organic fillers, powders such as metal powders and pigments, particles, and foils.

The pressure-sensitive adhesive sheet of the present invention comprises a support made of a plastic film such as a polyester film, a non-woven fabric, paper or the like, and a layer comprising the above-mentioned pressure-sensitive adhesive composition on one or both sides of the support. The cross-linked layer is provided on one side to a thickness of about 10 to 150 μm,
It is in the form of a tape, a tape, or the like, and a release liner is usually attached to the adhesive surface composed of the above layer.

As this release liner, a release liner that has not been subjected to silicone treatment can be used, and a polyolefin-based film is particularly preferably used. Examples of the polyolefin-based film include a film made of polyethylene, polypropylene, polymethylpentene, an ethylene-propylene copolymer or a mixture thereof, and a film whose surface is processed with the same polyolefin (for example, the above-mentioned polyolefin film and paper). Or a film laminated with other films).

The pressure-sensitive adhesive sheet of the present invention thus constituted comprises a layer comprising the above-mentioned pressure-sensitive adhesive composition together with a specific polycarbonate structure represented by the formula (A), B
The improved initial tackiness is exhibited by using as a main component a specific cyclic or acyclic condensed polymer having a dioil or diol structure represented by (1) or (B2).
In addition, the original adhesive force is large, and the release liner made of the polyolefin-based film bonded to the adhesive surface and not subjected to silicone treatment is excellent in releasability, and can be easily peeled off with a small force when used. .

It should be noted that, in addition, Japanese Patent Application Laid-Open No. 8-41185
In Japanese Patent Application Laid-Open Publication No. H10-157, a polyester carbonate containing a polyester of dimer-fatty acid and dimer-fatty acid diol is disclosed. However, this polyester carbonate is an aromatic polycarbonate in the manufacture of automobile bodies.
The purpose of the present invention is to improve the fuel oil resistance and the transparency of the polyester resin, and to use the aliphatic polycarbonate as described in the present invention.
This is significantly different from the base based on a condensation polymer having a carbonate structure, and there is no description that suggests that the above-mentioned carbonate material is used for the pressure-sensitive adhesive. Therefore, the existence of the above publication does not affect the novelty and inventive step of the present invention at all.

[0025]

Next, an embodiment of the present invention will be described in more detail. However, the scope of the present invention is not limited by the following examples. In the following, “parts” means “parts by weight”.

Example 1 A four-neck separable flask was equipped with a stirrer, a thermometer and a water separation tube, and this was equipped with polycarbonate [Daicel Chemical Industries, Ltd. "PLACCEL CD220P".
L ", hydroxyl value: 55.1 KOH mg / g] 300 g, hydrogenated dimer acid (" Pripol "manufactured by Unichema)
1010 ", acid value 192.6 KOH mg / g) 87.5
g, tetraisopropyl titanate (hereinafter, referred to as catalyst)
80 mg of TPT) was added, and stirring was started in the presence of a small amount of xylene as a solvent for discharging reaction water.
The temperature was raised to and maintained at this temperature. After a short time,
Water effluent separation was observed and the reaction began to proceed. About 16
The reaction was continued for an hour to obtain a polyester having a weight average molecular weight of 28,000.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of the polyester, 3 parts (solid content) of a hexamethylene diisocyanate adduct of trimethylolpropane [“Coronate HL” manufactured by Nippon Polyurethane KK] was added as a crosslinking agent. And an adhesive composition. This was applied on a 38 μm thick polyethylene terephthalate film (hereinafter referred to as PET film) by an applicator, and then dried at 130 ° C. for 5 minutes to obtain a 50 μm thick adhesive composition. Layer was formed. A polyethylene film having a thickness of 60 μm was adhered to the adhesive surface as a release liner, and aging was performed in an atmosphere at 50 ° C. for 3 days as an after-cure to prepare an adhesive tape.

Example 2 A four-necked separable flask was equipped with a stirrer, a thermometer and a water separation tube, and this was equipped with a polycarbonate [Daicel Chemical Industries, Ltd. "PLACCEL CD220P".
L ", hydroxyl value: 55.1 KOHmg / g], 320 g, hydrogenated dimerdiol [" Pespor HP-1000 "manufactured by Toagosei Co., Ltd., hydroxyl value: 200 KOHmg / g] 8
0 g, sebacic acid 61.2 g, TPT 80 mg as catalyst
, And the mixture was heated to 180 ° C. in the presence of a small amount of xylene as a solvent for discharging reaction water while stirring was started, and maintained at this temperature. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 24 hours to obtain a polyester having a weight average molecular weight of 49,000.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of this polyester, a tolylene diisocyanate adduct of trimethylolpropane as a crosslinking agent [Nippon Polyurethane Co., Ltd.]
"Coronate L") (solid content) was added to obtain an adhesive composition. This was applied on a 38 μm-thick PET film using an applicator, and then applied at 130 ° C.
For 5 minutes to form a layer of a pressure-sensitive adhesive composition having a thickness of 50 μm. 6 thickness as a release liner on the adhesive surface
Attach a 0μm polyethylene film,
Aging was performed in a 50 ° C. atmosphere for 3 days to prepare an adhesive tape.

Example 3 A four-necked separable flask was equipped with a stirrer, a thermometer, and a water separation tube, and this was equipped with a polycarbonate [Daicel Chemical Industries, Ltd. "PLACCEL CD210P".
L ", hydroxyl value: 115 KOHmg / g] 320 g, ester compound of hydrogenated dimer acid and hexanediol [" Pespol 601 "manufactured by Toagosei Co., Ltd., hydroxyl value: 5
3.3 KOH mg / g] 80 g, sebacic acid 74.8 g,
80 mg of TPT was charged as a catalyst, and stirring was started in the presence of a small amount of xylene as a solvent for discharging reaction water.
The temperature was raised to 0 ° C. and kept at this temperature. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 25 hours, and the weight average molecular weight was 72,000.
A polyester was obtained.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of the polyester, 2 parts (solid content) of a hexamethylene diisocyanate adduct of trimethylolpropane [“Coronate HL” manufactured by Nippon Polyurethane KK] was added as a crosslinking agent. And an adhesive composition. This was applied to a 38 μm-thick PET film using an applicator, and
After drying at 0 ° C. for 5 minutes, a layer composed of the pressure-sensitive adhesive composition having a thickness of 50 μm was formed. A polyethylene film having a thickness of 60 μm was adhered to the adhesive surface as a release liner, and aging was performed in an atmosphere at 50 ° C. for 3 days as an after-cure to prepare an adhesive tape.

Example 4 A four-necked separable flask was equipped with a stirrer, a thermometer and a water separation tube, and this was equipped with polycarbonate [Diocel Chemical Industries, Ltd. "PLACCEL CD220P".
L ", hydroxyl value: 55.1 KOH mg / g] 320 g, ester compound of hydrogenated dimer acid and hydrogenated dimer diol [" Pespol 801 "manufactured by Toagosei Co., Ltd., hydroxyl value: 52 .7KOHmg / g] 80 g, azelaic acid 3
6.4 g and TPT (80 mg) were charged as a catalyst, and the mixture was heated to 180 ° C. while stirring and was maintained at this temperature in the presence of a small amount of xylene as a solvent for discharging reaction water. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 25 hours, and the weight average molecular weight was 7
6,000 polyesters were obtained.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of the polyester, 2 parts (solid content) of a hexamethylene diisocyanate adduct of trimethylolpropane [“Coronate HL” manufactured by Nippon Polyurethane KK] was added as a crosslinking agent. And an adhesive composition. This was applied to a 38 μm-thick PET film using an applicator, and
After drying at 0 ° C. for 5 minutes, a layer composed of the pressure-sensitive adhesive composition having a thickness of 50 μm was formed. A polyethylene film having a thickness of 60 μm was adhered to the adhesive surface as a release liner, and aging was performed in an atmosphere at 50 ° C. for 3 days as an after-cure to prepare an adhesive tape.

Example 5 A four-necked separable flask was equipped with a stirrer, a thermometer and a condenser, and a polycarbonate [Dialcel Chemical Industries, Ltd. "PLACCEL CD210"
PL ", hydroxyl value: 115 KOH mg / g] 200 g, ester compound of hydrogenated dimer acid and hexanediol [" Pespol 601 "manufactured by Toagosei Co., Ltd., hydroxyl value: 53.3 KOH mg / g] 200 g , Diphenylmethane diisocyanate (75 g), toluene (100 g), and TPT (80 mg) as a catalyst.
The reaction was continued for an hour to obtain a polyurethane having a weight average molecular weight of 26,000.

This polyurethane was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of the polyurethane, as a crosslinking agent, a tolylene diisocyanate adduct of trimethylolpropane [Nippon Polyurethane Co., Ltd.]
"Coronate L") (solid content) was added to obtain an adhesive composition. This was applied on a PET film having a thickness of 38 μm using an applicator, and dried at 130 ° C. for 5 minutes to form a layer made of a pressure-sensitive adhesive composition having a thickness of 50 μm. 60 μm thickness as a release liner on the adhesive surface
And then aged for 3 days in an atmosphere of 50 ° C. as an after cure.
An adhesive tape was produced.

Comparative Example 1 A four-neck separable flask was equipped with a stirrer, a thermometer, and a water separation tube, and a polycarbonate [Dialcel Chemical Industries, Ltd. "PLACCEL CD220P"
L ", hydroxyl value: 55.1 KOHmg / g], 300 g, sebacic acid, 30 g, and TPT, 80 mg, were charged. The mixture was heated to 180 DEG C. while stirring was started in the presence of a small amount of xylene as a reaction water discharge solvent. Hold at temperature. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 16 hours to obtain a polyester having a weight average molecular weight of 37,000.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of the polyester, 3 parts (solid content) of a hexamethylene diisocyanate adduct of trimethylolpropane [“Coronate HL” manufactured by Nippon Polyurethane KK] was added as a crosslinking agent. And an adhesive composition. This was applied on a 38 μm-thick PET film using an applicator, and
After drying at 0 ° C. for 5 minutes, a layer composed of the pressure-sensitive adhesive composition having a thickness of 50 μm was formed. A polyethylene film having a thickness of 60 μm was adhered to the adhesive surface as a release liner, and aging was performed in an atmosphere at 50 ° C. for 3 days as an after-cure to prepare an adhesive tape.

Comparative Example 2 A four-necked separable flask was equipped with a stirrer, a thermometer and a water separation tube, and hydrogenated dimerdiol ["Pespor HP-1000" manufactured by Toagosei Co., Ltd.] , Hydroxyl value:
200 KOHmg / g] 300 g, sebacic acid 109 g,
80 mg of TPT was charged as a catalyst, and stirring was started in the presence of a small amount of xylene as a solvent for discharging reaction water.
The temperature was raised to 0 ° C. and kept at this temperature. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 24 hours, and the weight average molecular weight was 29,000.
A polyester was obtained.

This polyester was diluted with toluene to a solid concentration of 50% by weight. To 100 parts (solid content) of this polyester, a tolylene diisocyanate adduct of trimethylolpropane as a crosslinking agent [Nippon Polyurethane Co., Ltd.]
"Coronate L") (solid content) was added to obtain an adhesive composition. This was applied on a PET film having a thickness of 38 μm using an applicator, and dried at 130 ° C. for 5 minutes to form a layer made of a pressure-sensitive adhesive composition having a thickness of 50 μm. 60 μm thickness as a release liner on the adhesive surface
And then aged for 3 days in an atmosphere of 50 ° C. as an after cure.
An adhesive tape was produced.

With respect to each of the adhesive tapes of Examples 1 to 5 and Comparative Examples 1 and 2, the initial adhesive strength, adhesive strength, and peel strength of the release liner were measured in the following manner. These results were as shown in Table 1 below.

<Measurement of Initial Adhesive Strength> An aluminum plate or an acrylic (polymethyl methacrylate) plate was used as an adherend, and an adhesive tape (20 mm × 100 mm) was adhered with a 200 g roller. , Ambient temperature 23 ° C, sticking time 10
The 180 ° peel adhesion was measured by a universal tensile tester under the conditions of a peeling speed of 300 mm / min for 2 seconds.

<Measurement of Adhesive Strength> An aluminum plate and an acrylic (polymethyl methacrylate) plate were used as adherends.
After affixing an adhesive tape (20 mm x 100 mm) with a 2 kg roller, the test was performed using an all-purpose tensile tester under the conditions of an ambient temperature of 23 ° C, a sticking time of 30 minutes, and a peeling speed of 300 mm / min.
0 ° Peel adhesion was measured.

<Measurement of Peeling Force of Peeling Liner> The peeling force of the peeling liner bonded to the adhesive surface was measured by a universal tensile tester under the conditions of an ambient temperature of 23 ° C., a peeling angle of 180 °, and a peeling speed of 300 mm / min. did.

[0044]

As is clear from the results in Table 1 above, each of the pressure-sensitive adhesive tapes of Examples 1 to 5 of the present invention has excellent adhesive strength and peelability of the release liner, and also has an initial tackiness. It turns out that it is excellent. On the other hand, the pressure-sensitive adhesive tape of Comparative Example 1 was excellent in the adhesive strength and the peelability of the release liner, but was inferior in initial tackiness. Although excellent in initial tackiness, the adhesive strength is slightly low, and the peelability of the release liner is poor.

[0046]

As described above, the present invention comprises, as a main component, a condensed polymer having a specific polycarbonate structure and a specific cyclic or acyclic di-oil or diol structure. By this, it is possible to provide a pressure-sensitive adhesive composition having a high adhesive strength, excellent release properties of a release liner not subjected to silicone treatment, and improved initial tackiness, and a pressure-sensitive adhesive sheet thereof. These can be used sufficiently for electronic equipment applications that do not like the presence of silicon, high-speed continuous bonding work that requires instantaneous bonding, and applications where stress is applied immediately after bonding. Can be.

Claims (5)

[Claims] 1. a) the following formula (A): (R is a linear or branched aliphatic hydrocarbon group having 2 to 20 carbon atoms), and b) the following formula (B1); (R ¹ is a cyclic or acyclic saturated hydrocarbon group having 34 carbon atoms) or the following formula (B2); -OR ² -O- ... (B2) (R ² is a cyclic or acyclic saturated hydrocarbon group having 36 carbon atoms), and a condensed polymer having at least one of the structures represented by the following formulas: Composition. 2. The structure represented by the formula (B1) has a carbon number of 1
8 derived from hydrogenated dimer acid obtained by hydrogenating the dimer acid of unsaturated fatty acid, and the structure represented by the formula (B2) is a hydrogenated dimer obtained by reducing the above hydrogenated dimer acid. The pressure-sensitive adhesive composition according to claim 1, which is derived from diol. 3. A pressure-sensitive adhesive sheet having a layer comprising the pressure-sensitive adhesive composition according to claim 1 on one or both sides of a support. 4. The pressure-sensitive adhesive sheets according to claim 3, wherein a release liner not subjected to silicone treatment is bonded to the pressure-sensitive adhesive surface. 5. The pressure-sensitive adhesive sheet according to claim 4, wherein the release liner not subjected to silicone treatment is a polyolefin-based film made of polyethylene, polypropylene, polymethylpentene, ethylene-propylene copolymer or the like.
Kind.