JP3427323B2 - Adhesive composition - Google Patents

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, and more specifically to a specific acrylic monomer and a monomer having a peroxy group and a copolymerizable double bond in its molecule as essential components. The present invention relates to a novel pressure-sensitive adhesive composition that can be crosslinked by heat and crosslinked by active energy rays.

[0002]

2. Description of the Related Art The following means have been conventionally known to balance the three major elements of an adhesive.

Crosslinking by adding a crosslinking agent having a reactive group capable of reacting a functional group to a polymer in which a functional group such as a hydroxyl group or a carboxyl group is pendant to a side chain of a copolymer (main component acrylic resin system) and thermally reacting Examples of the agent include polyisocyanate, melamine resin, and organometallic compound.

Then, a copolymer having a functional group such as a carboxyl group and a hydroxyl group is blended with a copolymer containing an N-methylol group to cause a crosslinking reaction. A monomer having an organic peroxide structure is copolymerized in the copolymer and then crosslinked. The photoinitiator was added to the polymer of Arukookishi alkyl (meth) acrylate is crosslinked by ultraviolet rays.

The pressure-sensitive adhesive obtained from the above-mentioned known acrylic resin composition is processed into various forms as a practically useful composition by selecting the degree of crosslinking and the Tg of the copolymerization component, for example, single-sided pressure-sensitive adhesive processing, double-sided pressure-sensitive adhesive processing. It is widely used for decorative sheets for surface protection, masking, electrical insulation, nameplate fixing, article fixing, surface protection, etc.

Heretofore, the balance of adhesive strength, cohesive strength and adhesiveness (tack) has been an important factor for constructing an appropriate adhesive. Furthermore, the stability of the above-mentioned elements of the adhesive, the durability after application, and the weather resistance are required. A pressure-sensitive adhesive made of an acrylic resin composition is useful as a material satisfying the above requirements. The acrylic pressure-sensitive adhesive composition known as a publicly known example is as follows.

This is a pressure-sensitive adhesive composition in which an organic peroxide is added to an acrylic or resin-based pressure-sensitive adhesive polymer and heat-crosslinked to improve cohesive force and balance the pressure-sensitive adhesive force and tackiness (tack).

Crosslinking capable of cross-linking with carboxyl groups and hydroxyl groups in the polymer by forming a polymer in which a monomer having a reactive functional group (such as carboxyl group and hydroxyl group) is copolymerized in an acrylic resin adhesive polymer. Agent for example
It is a pressure-sensitive adhesive composition in which cohesive force, adhesive force, and tackiness (tack) are balanced by a crosslinking reaction with a polyfunctional polyisocyanate, a melamine resin, a polymer containing a methylol group, and the like.

A pressure-sensitive adhesive polymer obtained by copolymerizing an acrylic resin-based pressure-sensitive adhesive polymer with a monomer having a carboxyl group is used as an organometallic compound such as aluminum alcooxide.
It is a pressure-sensitive adhesive composition in which a cohesive force, an adhesive force, and an adhesive property (tack) are balanced by forming a cross-linking structure with a titanium alcooxide or the like).

An active energy ray-curable pressure-sensitive adhesive composition (JP-A-60-179484) having a general formula In the formula, R ₁ is H or CH ₃ R ₂ is an alkylene group having 1 to 4 carbon atoms, R ₃ is an alkyl group having 1 to 4 carbon atoms, and n is an integer of 1 to 4 which is a homopolymer or copolymer and is an electron beam. It is an adhesive composition in which crosslinking or a photoinitiator is added by irradiation and crosslinked by irradiation of ultraviolet rays to balance the adhesive strength, cohesive strength, and tackiness (tack).

A self-crosslinking pressure-sensitive adhesive composition containing an organic peroxide structure (peroxy group) and an ethylenically unsaturated bond in an acrylic resin-based copolymer pressure-sensitive adhesive polymer (JP-A-62-62).
-100569).

[0012]

However, although the above-mentioned pressure-sensitive adhesive composition achieves a useful function depending on the intended use, a plastic resin plate, particularly a polycarbonate resin plate,
When it is attached to a composite resin plate such as a polycarbonate resin plate and an acrylic resin plate, volatile components generated from the polycarbonate resin plate affect and swells, bubbles, etc. at the interface between the polycarbonate resin plate of the adherend and the adhesive layer. Occurs. In this phenomenon, defects such as blisters and bubbles are remarkably promoted by accelerating heating of the adherend. The above-mentioned composition has the above-mentioned drawbacks and cannot be put to practical use.

The above-mentioned crosslinking reaction of the known composition is classified into (1) reaction by heat, (2) reaction by ultraviolet irradiation, and (3) crosslinking reaction by heat or ultraviolet irradiation.

The pressure-sensitive adhesive obtained from the above composition is a polyester film, a vinyl chloride film, an acetate film,
It is applied to non-woven fabric, metal foil, etc. and used for the above-mentioned applications. However, when it is adhered to a specific adherent polycarbonate resin plate or a laminated plate of polycarbonate resin and acrylic resin and left in a hot atmosphere, the resin plate is volatile components (H ₂ O) generated from the resin plate. Many bubbles are generated at the interface of the adhesive surface. Therefore, it cannot be used because the transparency and appearance of the adhered surface are significantly impaired. The novel pressure-sensitive adhesive composition of the present invention solves the above-mentioned problems and provides a tacky-adhesive composition in which important factors as pressure-sensitive adhesives, that is, cohesive force, pressure-sensitive adhesive force and tack are well balanced. . Further, the product of the present invention does not require the use of the crosslinking agent of the conventional crosslinking adhesive. If used, the amount of the cross-linking agent used may be smaller than that of the conventional cross-linking adhesive.

[0015]

SUMMARY OF THE INVENTION The inventors of the present invention have the above-mentioned problems in order to prevent bubbles from being generated on the adhered surface due to volatile components (H ₂ O) generated from the adherend resin plate for a long period of time. extensive studies to result over, it was found that it is useful to use the copolymerization component of the monomer peroxy compound and Arukookishi alkyl (meth) acrylate having a double bond. That is, it has been found that an adhesive composition in which a peroxy group is decomposed by an operation such as heating of this copolymerization component is a useful constitution for solving the above-mentioned problems. The reason for this is not clear, but polymer radicals and alcooxy radicals generated by the decomposition of pendant peroxy groups in the copolymer, and side chain alcooxy groups (alcooxyalkyl acrylate or alcooxyalkyl methacrylate) in the copolymer. It is presumed that the reaction product associated with the action of is a useful composition for solving the above-mentioned problems.
Since the product of the present invention has a peroxy group pendant in the copolymer, it can also be cured by ultraviolet rays and electron beams by absorbing and decomposing at a wavelength in the ultraviolet region like ordinary organic peroxides.

The product of the present invention has been completed based on the above findings and has the general formula In the formula, R ₁ is hydrogen or an alkyl group having 1 to 5 carbon atoms R ₂ , R ₃ is an alkyl group having 1 to 4 carbon atoms or hydrogen R ₄ is hydrogen or an alkyl group having 1 to 12 carbon atoms, or 5 carbon atoms The cycloalkyl group m of ~ 7 is an integer of 0-4. 0.2 to 20 parts by weight of a peroxy compound having a double bond represented by

General formula In the formula, R ₅ is hydrogen or a methyl group R ₆ is an alkylene group having 1 to 3 carbon atoms (C _n H _2n ) R ₇ is an alkyl group having 1 to 4 carbon atoms (C _n H _{2n + 1} ) m is 1 composition comprising a copolymer of a and B having the composition Arukookishi alkyl (meth) acrylate from 99.8 to 80 parts by weight having a double bond represented by 2 integer.

General formula In the formula, R ₈ is hydrogen or a methyl group (CH ₃ ), R ₉ is an alkyl group (C _n H _{2n + 1} ), and a monomer represented by the general formula [C] is a monomer A + B + C. =
A is 1.0 to 10% by weight and B is 30 to 100 parts by weight.
A composition obtained by copolymerizing 90% by weight or less of 69% by weight or less.

As the modifying monomer [D], a monomer copolymerizable with the reactive monomer having a double bond represented by the general formula of A, B and C can be used. Copolymer A + B + D [A] is 1.0 in 100 parts by weight.
A composition in which the modifying monomer is copolymerized at 69 wt% or less in a composition containing 10 to 10 wt% and 30 to 90 wt% of [B]. Copolymer A + B + C + D 100 parts by weight of [A] is 1.
0 to 10% by weight, [B] is 30 to 90% by weight,
[C] + [D] A composition copolymerized with 69% by weight or less.

As the peroxy group-containing double bond-containing monomer of the general formula [A] of the adhesive composition, t-butyl peroxy vinyl carbonate, t-hexyl peroxy vinyl carbonate and t-butyl isopropenyl carbonate can be used. , 1,1,3,3 tetramethylpropylperoxyallylcarbonate, t-butylperoxymethallylcarbonate, t-butylperoxy (3-butynyl) carbonate, t-butylperoxyallylcarbonate and the like. These peroxy group-containing unsaturated monomers can be copolymerized with general formulas [B] and [C] and a modifying monomer to obtain a copolymer having a pendant peroxy group. The peroxy group is decomposed by heat or light to give a crosslinked structure.

Next, the alcooxyalkyl (meth) acrylate of the general formula [B] of the adhesive composition is copolymerized with the above-mentioned unsaturated monomer containing a peroxy group of the general formula [A] to form a polymer. To do. When the glass transition point of the alcooxyalkyl (meth) acrylate is low, for example, in the case of methoxyethyl acrylate, propoxyethyl acrylate, butoxyethyl acrylate, the copolymer with the unsaturated monomer containing a peroxy group is normally adhesive. A copolymer can be obtained. Since this copolymer has a pendant peroxy group on the side chain, the peroxy group is decomposed by heat, and a novel cross-linked pressure-sensitive adhesive of the present invention, that is, it is attached to a laminate of a polycarbonate resin and an acrylic resin, Volatile components (H ₂
The composition has no effect of O) and does not generate bubbles on the adhered surface.

Further, the above-mentioned copolymer absorbs wavelength energy in the ultraviolet region, forms a crosslinked structure like heat, and can obtain a pressure-sensitive adhesive in which cohesive force, adhesive force and tack are balanced.

As the monomer of the general formula [B], methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, propoxymethyl (meth) acrylate,
Butoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, methoxypropyl (meth) acrylate, ethoxypropyl (meth) acrylate, propoxypropyl (meth)
Acrylate, butoxypropyl (meth) acrylate, 2-methoxy-1-methyl-propyl (meth) acrylate, 2-propoxy1-methylpropyl (meth)
Acrylate, 2-butoxy-1-methylpropyl (meth) acrylate is used. Of the general formula [B] Examples of the unsaturated monomer having n of 2 include ethoxyethoxy (meth) acrylate, methoxypropylene glycol mono (meth) acrylate, methoxydiethylene glycol mono (meth) acrylate, and methoxytriethylene glycol mono (meth) acrylate. In the product of the present invention, one having n of 1 to 3 is used.

The (meth) acrylic acid ester of the general formula [C] of the adhesive composition of the present invention is represented by the general formulas [A] and [B] which are the essential components of the present invention. It is possible to copolymerize with a monomer group having a saturated bond. As (meth) acrylic acid esters R ₈ represents hydrogen or a methyl group, and R ₉ represents a linear or branched alkyl group having 1 to 24 carbon atoms. Examples of these esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and tertiary (meth) acrylate. Butyl, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylate
Examples include cyclohexyl acrylate.

[0025] (Meth) acrylic acid as a reactive monomer having a functional group, itaconic acid, crotonic acid, maleic acid anhydride, 2-hydroxyethyl (meth) acrylate, grayed Rishijiru (meth) acrylate, (meth) acrylamide, N-methylol A group-containing (meth) acrylate and its derivative, dimethylamino (meth) acrylate, etc. can be used. The ester group belonging to the general formula [C] is Ta of the copolymer.
By adjusting the (glass transition point), it is possible to adjust the adhesive strength, tack, etc. of the copolymer depending on the application.

Next, the modifying monomer is preferably copolymerizable with the above-mentioned general formulas [A], [B] and [C]. The modifying monomer is represented by the general formula [A], [B], [C].
By modifying the Tg (glass transition point) of the polymer by co-polymerization with the polymer, modification of the adhesive force, tack, cohesive force and formation of a crosslinked structure in the copolymer by using a monomer having a reactive group You can do it.

Examples of monomers for modifying the monomer of the group [D] are vinyl acetate, vinyl propionate, (meth) acrylonitrile, styrene and its modified products, aryl glycidyl ether and aryl glycidyl methacrylate, vinylpyrrolidone, Cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, mono (2- (meth) acryloyloxyethyl acid) phosphate, etc. can be used.

Next, as a polymerization catalyst for forming the copolymer of the present invention, a catalyst which does not decompose the peroxy group of the general formula [A] during preparation of the polymer, that is, a catalyst at a low temperature Is decomposed, and the general formulas [A], [B], [C],
Those that react promptly with the double bond of the unsaturated monomer of [D] are preferable.

As an example of such a catalyst, 2,2'-azobis (4-methoxy-2,4, dimethylvaleronitrile) 2,2'-azobis (2-cyclopropylpropionitrile) is used as an azo initiator. 2,2'-azobis (2,4-methylvaleronitrile) 2,2'-azobisisobutyronitrile 2,2'-azobis (2-methylbutyronitrile) 2,2'-azobis (2-methyl) Propionate) 4,4'-azobis (4-cyanovaleric acid) is used.

Further, as an organic peroxide catalyst, iso-butyryl peroxide, cumyl peroxyneodecanoate, diisopropyl peroxydicarbonate, di-n.
-Propyl peroxydicarbonate, cumyl peroxyneohexanonate, di (2-ethoxyethyl) peroxydicarbonate, di (methoxyisopropyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, t- Butyl peroxy neodecanoate, t-hexyl peroxy neohexaate, t-butyryl peroxy neohexanoate, t-
Butyl peroxypivalate, lauroyl peroxide, cumyl peroxy octate, benzoyl peroxide, etc. are used.

Next, reference will be made to the limitation of the compound of the general formula of the composition of the present invention and its action and effect.

When the amount of the monomer of the general formula [A] is less than 1.0 part by weight, a sufficient cohesive force cannot be obtained because the copolymer has a low degree of crosslinking. On the other hand, when the content of [A] is more than 20 parts by weight, the number of cross-linking points of the copolymer molecule becomes too large, so that the adhesive strength, tack, etc. are remarkably reduced, and the composition cannot be put to practical use.

When the amount of the monomer represented by the general formula [B] is less than 30% by weight, the effect of decomposing the peroxy group of the monomer [A] and the interaction effect are lowered, and the polycarbonate resin plate The inhibitory effect on the generated volatile components is reduced.
It is also insufficient for UV curing.

The product of the present invention contains the monomer of the general formula [A] in the copolymer composition in an amount of 0.2 to 20% by weight, preferably 1.0 to 10% by weight, and the monomer of the general formula [B]. Monomer of 10
The total amount of [A] + [B] + [C] + in any proportion of the general formula [C] and the modifying monomer is added to the monomer composition having a weight (%) or more, preferably 30% (%). [D] or [A] + [B]
A copolymer composition in which the total of + [D] is 100 parts by weight is a composition that achieves the effects of the product of the present invention.

[0035]

According to the pressure-sensitive adhesive composition of the present invention, a peroxy compound 1-10 wt% having a double bond in the molecule, alkoxy alkyl acrylates and / or alkoxy A
By using a copolymer containing 99 to 90% by weight of rurumethacrylate, it is possible to provide a crosslinkable pressure-sensitive adhesive composition useful for adherends, particularly for polycarbonate and acrylic resin plates.

[0036]

EXAMPLES Examples of the pressure-sensitive adhesive composition of the present invention are shown below.

Example 1 Copolymer Preparation In a three-necked flask having a volume of 1 liter equipped with a condenser, a thermometer, and a N ₂ (nitrogen) gas inlet tube, 42.8 g of methoxyethyl acrylate (MOEA) and 6.0 g of Pelomer AC were introduced. (7
0% active ingredient), acrylic acid (A, A) 8.0 g, vinyl acetate (VAc) 12.3 g, n-butyl acrylate (n-BA) 32.7 g, ethyl acetate 1 as a polymerization solvent.
81.0 g, 2,2 'asobis (2,4 as a polymerization catalyst
-Dimethylvaleronitrile) 0.08 g is charged. The temperature inside the reaction system was adjusted to 60 while the inside of the flask was replaced with N ₂ gas.
The polymerization reaction is carried out for 8 hours while maintaining the temperature at ℃. 50 g of ethyl acetate
The addition reaction was completed.

Comparative Example 1 The copolymerization procedure of the copolymer is the same as in Example 1. Methoxyethyl acrylate (MOEA) 42.8 in a 3-necked flask.
g, acrylic acid (A, A) 8.0 g, vinyl acetate (VA
_C ) 12.3 g, n-butyl acrylate (n-BA)
36.4 g, 2-hydroxyethyl methacrylate (H
EMA) 0.5 g, ethyl acetate 181 as a polymerization solvent
g, 0.08 g of 2,2'azobisisobutyronitrile as a polymerization catalyst are charged. The polymerization reaction is carried out for 8 hours. The reaction was completed by adding 52 g of ethyl acetate.

Table 1 shows the properties of the polymers of Example 1 and Comparative Example 1. The difference between the copolymer components of Example 1 and Comparative Example 1 is the presence or absence of Pelomer AC and the presence or absence of 2-hydroxyethyl methacrylate. In Comparative Example 1, the reason why 2-hydroxyethyl methacrylate was contained in the copolymer was to introduce a cross-linking structure and impart cohesive force because the copolymer is thermoplastic.

[0040]

[Table 1]

The copolymer of Comparative Example 1 has the same composition as that of the prior art, which requires cohesive force. Since the copolymer of Comparative Example 1 is thermoplastic, it has a low cohesive force and flows at a relatively high temperature, making it difficult to put into practical use.

JIS is a simple method for evaluating cohesive force.
Z0273 and JISZ1528 have evaluation items with retention. In this method, a sample adhesive tape is attached on a stainless steel plate to form a 25 mm × 25 mm joint. When the sample tape is a double-sided tape, it is lined with a 25 μ-thick polyester tape. A load of 1 kg is applied to the lower end of the above-mentioned test piece in an atmosphere of 40 ° C., and the shift after 1 hour is examined. In the present invention, the measurement temperature is evaluated in a temperature atmosphere of 100 ° C. in order to clarify the difference in cohesive force of the adhesive material. According to this method, the holding power of the copolymer of Comparative Example 1 is within 10 seconds / 100 ° C.
Cohesive failure with.

Next, the performance of the copolymer of Comparative Example 1 crosslinked by a known crosslinking method and the performance of the copolymer of Example 1 of the present invention will be shown below. As a method for evaluating the performance of the pressure-sensitive adhesive, a sample tape was prepared as described below, and the evaluation items are specified below.

Preparation of Sample Adhesive Tape An adhesive is applied to the polyester film of # 25 (dry thickness 35 ± 3μ). Dry and react for 7 minutes in an air circulation oven adjusted to 155 ° C to prepare a sample tape for evaluation.

Evaluation item Adhesive strength: JIS Z0237-8.3 ... 180 degree peeling method Tack (ball rolling method): 12 ... Angle of inclined plate 30 degree Holding force: 11 ... Atmosphere temperature 1
00 ° C. adhesive thickness: 〃 5.2 ‥‥ meter micrometer plastic resin plate: Name N6ULO5 Mitsubishi Gas Chemical Co., thickness 3 ^mmt polycarbonate resin and properties of the laminate N6ULO5 of acrylic resin: Appearance transparent elastic modulus. ′ E 1.6 × 10 ¹⁰ dyne / cm ² loss elastic modulus. ″ E 7.0 × 10 ⁸ dyne / cm ² Tg 60 ° C. Frequency 35 Hz Moisture 0.655 μg / mm ²

The resin plate is cut into a size of 5 cm × 10 cm, the polycarbonate surface is wiped with ethyl alcohol and the acrylic surface is wiped with methyl alcohol, and then wiped with dry gauze to adjust the sticking surface of the adhesive tape. The sample tape is pressure-bonded with a roller so as to prevent wrinkles, air, etc. from entering, and is adhered to the resin plate to form a 5 cm × 10 cm adhered surface on the resin plate. After being left at room temperature for 3 hours, it is left in a drying oven at 80 ° C. for 72 hours. After that, the appearance is taken out.

Outside the judgment criteria Bubbles on the adhered surface ××× 80% or more Bubbles ×× 50% or more to 80% Bubbles × 10% to 50% Bubbles △ 0.5 or more to 10% Bubbles ○ Good adhesion without bubbles The appearance was judged by the cumulative area (%) of the bubble generation area after 80 ° C. for 72 hours with the landed area as 100%.

Specific examples of the present invention are shown below. Formulation for improving the cohesive strength of the copolymer of Comparative Example 1-known methods

[0049]

[Table 2]

[0050]

[Table 3]

As shown in Table 3, the pressure-sensitive adhesive composition of the present invention and the pressure-sensitive adhesive composition of the comparative example also have three elements of pressure-sensitive adhesive, such as pressure-sensitive adhesive force, holding power, and tack, with respect to a standard adherend (stainless plate). There is no significant difference when compared (however, Comparative Example 1-2 has low adhesive strength). However, in the comparative example (known pressure-sensitive adhesive composition), bubbles are remarkably generated at the interface between the plastic surface and the adhesive surface when it is adhered to the plastic surface and left in an atmosphere at 80 ° C. The composition of Example 1 of the present invention does not generate bubbles and is an excellent adhesive composition. The difference between the pressure-sensitive adhesive composition of the present invention and the conventionally known cross-linking method is that in the composition of Example 1, the peroxy segment pendant in the copolymer chain is decomposed by heating to decompose the polymer radical and t-butyloxy. It is presumed that a radical, a methoxy group in the copolymer, and a function of oxygen in the air act appropriately to form a crosslinked structure, which diffuses water generated from the resin plate into the adhesive.

Example 2 The copolymers of Example 2 and Comparative Example 2 were prepared under the same operations and conditions as in Example 1 and Comparative Example 1. Table 4 shows the composition of the copolymer and the properties of the copolymer.

[0053]

[Table 4]

The copolymer of Comparative Example 2 is thermoplastic and can easily react with a crosslinking agent which reacts with active hydrogen, such as polyisocyanate, to improve cohesive force. Such a copolymer has a conventionally known composition. The composition of Example 2 is a self-curing copolymer composition in which the copolymerization amount of methoxyethyl acrylate is lower than that of the copolymer composition of Example 1.

Next, the modification of Comparative Example 2 was carried out according to the known formulation in the formulation shown in Table 5.

[0056]

[Table 5]

Table 6 shows the performance of Example 2 and Comparative Examples 2-1 and 2-2.

[0058]

[Table 6]

Example 3 The copolymers of Example 3 and Comparative Examples 3 and 3'were prepared under the same operations and conditions as in Example 1 and Comparative Example 1. Table 7 shows the composition of the copolymer and the properties of the copolymer.

[0060]

[Table 7]

The copolymer of Comparative Example 3 is a self-curing, tacky copolymer capable of crosslinking the copolymer by heating, and it is substantially unnecessary to add a crosslinking agent. Such a composition is useful as an adhesive. Such a composition is disclosed in JP-A-62-100569. The present invention is a further improvement of JP-A-62-100569 and has novelty.

Table 8 shows the formulation of an example in which the polymer of Comparative Example 3'is introduced into the copolymer by a known crosslinking means to improve the cohesive force. Table 9 shows the performance of Example 3, Comparative Example 3'-1, and Comparative Example 3.

[0063]

[Table 8]

[0064]

[Table 9]

Examples 4 and 5 Example 4 shows an example in which the copolymerization amount of the reactive monomer having an alcooxy group and the monomer having an organic peroxide structure capable of copolymerization was changed. The composition of the copolymer of Example 4 is shown in Table 10. The polymerization conditions and operations were the same as in Example 1.

[0066]

[Table 10]

Table 11 shows the performance of Examples 4 and 5 .

[0068]

[Table 11]

Examples 6, 7, and 8 In Examples 6, 7, and 8, the copolymer composition was a copolymer of a peroxy compound having a double bond, an alcoholoxyalkyl (meth) acrylate, and an acrylic ester (Example 6). )
Examples of copolymers (Example 7) in the case of using vinyl acetate instead of and acrylate and Examples of the case in which acrylic acid is used (Example 8) are shown. Table 12 shows the composition of the copolymerization.
The polymerization conditions and operations were the same as in Example 1.

[0070]

[Table 12]

Table 13 shows the performances of Examples 6, 7 and 8.

[0072]

[Table 13]

From the above examples, the present invention is suitable for adherends, especially polycarbonates, which cannot be solved by the conventional crosslinking method only by the important characteristics of the pressure-sensitive adhesive, that is, the adhesive strength, cohesive strength and tack characteristics. I was able to get the result.

Next, an example of cross-linking the copolymer of the example with ultraviolet rays will be described. The example copolymer is applied to a 25 micron thick polyester film. 1 in the drying oven
Dry at 00 ° C. for 10 minutes to remove volatile matter, and form a 35 ± 3 micron pressure-sensitive adhesive layer on the polyester. The copolymers of the examples are self-crosslinking type, but at the above drying temperature, the peroxy groups are decomposed and the crosslinking reaction does not occur. 97 ° C 1
0 hour half-life, UV-active composition in which the copolymer of the present invention is active with respect to ultraviolet rays and the crosslinking reaction progresses and the cohesive force is improved and the ultraviolet reaction progresses even when the copolymer of the present invention is irradiated in air. As shown in Table 14, it is effective as a product.

[0075]

[Table 14] UV irradiation conditions Lamp light source: Metal halide lamp UVL4000M
-3-N Ushio Electric Height: 15 cm Speed: 1 m / min Electric power: 160 W / cm Ultraviolet wavelength: 200-400 nm Irradiation energy: 2.1 J / cm ²

From the results shown in Table 14, it is shown that the present invention can be an excellent adhesive having a well-balanced adhesive force, cohesive force and tack even in the presence of oxygen in the air. Further, the present invention is capable of promoting curing by adding a trace amount of a photoinitiator which cannot be considered in ordinary copolymers for the purpose of accelerating the reaction rate because the copolymer itself can be cured by active energy rays. is there.

From the above results, the pressure-sensitive adhesive composition of the present invention is a plastic material, especially polycarbonate, which could not be achieved by the conventional known technique by heat crosslinking.
It has excellent compatibility with acrylic resin surface, and this composition is a photoactive compound capable of forming a cross-linking structure by ultraviolet rays even in the absence of a photoinitiator, which is an essential component in conventional compounding systems. A new functionalized composition was completed.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0079]

As described above, according to the present invention,
When the ethylenic double bond is an aryl group, it has good co-polymerizability with non-conjugated monomers, but
The self-curing pressure-sensitive adhesive was able to be obtained only by using the acrylic polymer copolymer as it had good copolymerizability with monomers such as ethoxyethyl acrylate, propoxyethyl acrylate and butoxyethyl acrylate.

The self-curing pressure-sensitive adhesive composition of the present invention is applicable not only to the fields of conventional pressure-sensitive adhesive compositions, but also to many adherends, particularly polycarbonate resin surface and acrylic resin surface among plastic resin surfaces. When attached to the resin surface,
Especially useful.

Further, it is possible to adjust the two elements of the adhesive force and the tackiness (tack) while maintaining the cohesive force of the three elements of the adhesive.

UV curing is possible without using a photoinitiator.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-60-179484 (JP, A) JP-A-62-100569 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C09J 131/00-201/10 C08F 18/00-220/70

Claims (6)

(57) [Claims] 1. T-Butyl allyl peroxy carbonene
1 to 10% by weight and methoxyethyl acrylate 99
% To 90% by weight, which is a copolymer containing a peroxy group. 2. t-Butyl allyl peroxy carbonene
1 to 10% by weight and butoxyethyl acrylate 99
To 90% by weight of a peroxy group
Adhesive composition characterized by comprising
object. 3. t-Butyl allyl peroxy carbonene
1 to 10% by weight and 30 methoxyethyl acrylate
To 90% by weight and 10 to 70% by weight of a monomer having an ethylenically unsaturated double bond, the adhesive composition comprising a peroxy group-containing copolymer. . 4. t-Butyl allyl peroxy carbonene
1 to 10% by weight and butoxyethyl acrylate 30
~ 90 wt%, a single having an ethylenically unsaturated double bond
A copolymer containing 10 to 70% by weight of a monomer,
Adhesion characterized by comprising oxy group
Agent composition. 5. 5 to 20% by weight of the monomer having an ethylenically unsaturated double bond is (meth) acrylic acid,
Taconic acid, crotonic acid, maleic anhydride, (meth) ac
2-hydroxyethyl phosphate, glycidyl (meth) ac
Relate, (meth) acrylamide, N-methylol group
Existence (meth) acrylate and its derivative, and dimethyl
The pressure-sensitive adhesive composition according to claim 3 or 4 , wherein the pressure-sensitive adhesive composition is replaced with one selected from the group of amino (meth) acrylates . 6. A single having an ethylenically unsaturated double bond
5 to 20% by weight of the monomer was replaced with acrylic acid
The pressure-sensitive adhesive composition according to claim 3 or 4, characterized in that
object.