JP3377315B2 - Composition for pressure-sensitive adhesive for flexible PVC, pressure-sensitive adhesive product and bonded product - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composition for pressure-sensitive adhesive , pressure-sensitive adhesive.
Sex products and bonded articles, in particular, soft polyvinyl chloride moldings applied soft PVC pressure-sensitive adhesive composition, about sticky <br/> products and bonded products.

[0002]

2. Description of the Related Art Soft vinyl chloride (that is, soft polyvinyl chloride or soft vinyl chloride resin) is a dioctyl phthalate.
It contains low molecular weight plasticizers such as phthalates such as dibutyl phthalate, dioctyl adipate, dioctyl azelate and other dibasic acid esters, and phosphoric acid esters. This plasticizer transfers to the adhesive applied to the soft vinyl chloride and reduces the cohesive strength of the adhesive. (Meth) Acry
The following is an adhesive for soft PVC composed of a polymer.
Some of these are known, but these are described below.
Have a problem.

First, a pressure-sensitive adhesive for soft PVC, which is composed of a (meth) acrylic polymer having many polar groups introduced, has been proposed (Louis C. Graziano et al., Jou.
rnal of PLASTIC FILM & SH
EETING, Vol. 2, p. 95, 1986. reference). This adhesive has low initial adhesion and low tack. JP-A-4-154882 and JP-A-5-105
No. 857, Japanese Patent Publication No. 59-5634, Japanese Patent Laid-Open No.
No. 18,486 discloses a pressure-sensitive adhesive for soft vinyl chloride, which is composed of a copolymer obtained by copolymerizing an alkyl (meth) acrylate and a nitrogen-containing vinyl monomer. This pressure-sensitive adhesive has a problem that it has a low cohesive force and is susceptible to the transfer of the plasticizer.

In Japanese Patent Publication No. 58-1712, an ethylenically unsaturated monomer capable of having a Tg of a homopolymer or a copolymer of 273 K or more is subjected to addition polymerization in the presence of a (meth) acrylic polymer having a polar group. There has been proposed a soft vinyl chloride adhesive comprising a graft polymer.
This adhesive has a problem of low cohesive strength. Japanese Examined Patent Publication (Kokoku) No. 58-18958 proposes a pressure-sensitive adhesive for soft vinyl chloride, which comprises a polymer blend obtained by adding an acrylonitrile-butadiene copolymer rubber to a (meth) acrylic polymer. This adhesive has a problem of low adhesive strength and low cohesive strength.

Japanese Patent Publication No. 58-14474 proposes an adhesive for soft PVC containing a plasticizer. This adhesive has a problem that the contained plasticizer may bleed or stain the punching blade. In addition, conventional
The adhesive composition also has a low adhesive strength during long-term storage.
The problem of lowering the shelf life
There was also.

[0006]

An object of the present invention is to provide a pressure-sensitive adhesive for soft vinyl chloride which has an excellent balance between cohesive force and adhesive force, is less likely to cause a decrease in cohesive force due to migration of a plasticizer, and has excellent shelf life. It is to provide a composition for an adhesive to be used. Another object of the present invention is to provide an adhesive product and a bonded product which have an excellent balance between cohesive force and adhesive force, are less likely to cause a decrease in cohesive force due to migration of a plasticizer, and have excellent shelf life. .

[0007]

Means for Solving the Problems] soft PVC pressure-sensitive adhesive composition of the present invention includes an A acrylic-based polymer and an organic solvent.
The organic solvent includes a state dissolved and / or dispersed acrylic polymer. Acrylic polymer, the acrylic block polymer der made by a manufacturing method including the following preparatory steps and the first polymerization step addition step and the second polymerization step
It In preparing a first α capable of producing high glass transition temperature type polymer having a glass transition temperature of greater than or equal to the polyvalent mercaptan and 273K, first mixture comprising a β- unsaturated monomers: Preparation process is there.

First polymerization step : a step of obtaining a reaction mixture by carrying out radical polymerization of the first α, β-unsaturated monomer starting from the mercapto group of the polyvalent mercaptan. Addition step : a reaction mixture obtained by the first polymerization step, which is capable of forming a polymer that is incompatible with the high glass transition point type polymer and which contains a (meth) acrylic acid alkyl ester monomer And a step of obtaining a second mixture. Second polymerization step : a step of performing radical polymerization of the monomers contained in the second mixture. Adhesive products of the present invention, the fill
Support made of either film, sheet, tape or wallpaper
Formed on at least one side of the body using the adhesive composition
Soft polyvinyl chloride with a soft vinyl chloride adhesive layer
It is a product that can be attached to a molded product.

At least one of the bonded products of the present invention is
Are the soft polyvinyl chloride base materials,
A sticking formed by laminating a layer made of a composition for adhesives
It is a combination product.

[0010]

In the adhesive composition of the device description] [PSA composition The present invention, including acrylic polymer in a state of being dissolved and / or dispersed in an organic solvent,
Aforementioned preparation step and the first polymerization step and the adding step and the acrylic block that Ru produced by a manufacturing method and a second polymerization step
It is a polymer and its polymerization point is polyvalent mercaptan.
With the high glass transition type polymer obtained as a seed
It is a ril type block polymer (a). The polyvalent mercaptan used in the present invention is a compound having two or more mercapto groups per molecule, and the mercaptans in which the number of mercapto groups per molecule is 2, 3, ... It is called mercaptan, trivalent mercaptan, .... Examples of the polyvalent mercaptan include diesters of diols such as ethylene glycol and 1,4-butanediol and carboxyl group-containing mercaptans; compounds having three or more hydroxyl groups such as trimethylolpropane, pentaerythritol, and dipentaerythritol, and carboxyl. Group-containing mercaptan polyester compounds; compounds having three or more mercapto groups such as trithioglycerin; 2-di-n-butylamino-4,6-dimercapto-S-triazine, 2,4,6-trimercapto- Triazine polyvalent thiols such as S-triazine; Compound obtained by adding hydrogen sulfide to plural epoxy groups of polyvalent epoxy compound to introduce plural mercapto groups; Plural carboxyl groups of polyvalent carboxylic acid and mercaptoethanol Esterified Comprising an ester compound and the like can be mentioned, solely one of them, or may be used together 2 or more. here,
Carboxyl group-containing mercaptans include thioglycolic acid, mercaptopropionic acid, and thiosalicylic acid.
It is a compound having one mercapto group and one carboxyl group.

The polyvalent mercaptan used in the present invention is
From the viewpoint of efficiently producing a block polymer, and from the viewpoint of improving the performance of the resulting polymer by introducing a structure radially extending from the same center, preferably 2 to
Compounds having 10 mercapto groups (ie 2 to
A monovalent mercaptan), more preferably a compound having 3 to 6 mercapto groups (that is, a trivalent to hexavalent mercaptan). A mercaptan having only one mercapto group does not give a structure in which the polymer portion extends radially. A mercaptan having more than 10 mercapto groups does not have a structure extending radially from the same center, and thus the desired physical properties may not be exhibited.

The polyvalent mercaptan is a mercaptan having a valence of 3 to 6, trimethylolpropane trithioglycolate, trimethylolpropane trithiopropionate, pentaerythritol tetrakisthioglycolate, pentaerythritol tetrakisthiopropionate, At least one compound selected from dipentaerythritol hexakisthioglycolate and dipentaerythritol hexakisthiopropionate is preferable. The reason for this is that the block polymer that is formed has a star-shaped structure radially from the same center, so the effect of entanglement between polymer chains (for example, high cohesive force) and the morphological change of the phase separation structure can be expected. Because there is.

In the acrylic block polymer (a) used in the present invention, the plurality of radially extending polymer moieties are 2
It has the above different composition. This composition difference, when derived from a homopolymer, the difference in the monomer units constituting the polymer, the number average molecular weight of the polymer, or when derived from a copolymer, the monomer It can be obtained by the difference in the units, the number average molecular weight of the polymer, the ratio of the monomer units, and the like. The polymer portion usually has a number average molecular weight of 1,000 to
500,000, preferably 5,000-200,000
It is 0, more preferably 10,000 to 100,000. If the number average molecular weight of the polymer portion is less than the above range, it may not be possible to introduce properties based on the polymer portion into this block polymer, and if it exceeds the above range, the viscosity at the time of production becomes high, which is preferable in terms of productivity. There is a possibility that there is no.

In the acrylic block polymer (a) ,
The combination of polymer moieties having different compositions depends on the performance (or application) required of the block polymer. Basically, the combination of polymer parts is a combination of polymer parts derived from polymers having different glass transition points (Tg). By combining the polymer moieties derived from the polymers having different Tg's, the polymer moieties derived from the polymer having a low Tg form a continuous phase. As an example of such a block polymer, polymethylmethacrylate (PMMA), Tg
Polyacrylate (PBA) as low polymer
The combination of In the case of this combination, P
The number average molecular weight of MMA is preferably 5,000 to 200,000, and the number average molecular weight of PBA is 10,000 to 15
10,000 is preferable, and the weight ratio of PMMA / PBA is 1
The range of 0/90 to 90/10 is preferable. Outside of these ranges, sufficient performance may not be obtained. In order for the polymer portion derived from the polymer having a low Tg to form a continuous phase, the proportion of the polymer having a low Tg should be increased,
Alternatively, it is necessary to reduce the melt viscosity of a polymer having a low Tg.

In the acrylic block polymer (a) used in the present invention, the polyvalent methacrylate moiety is a residue of a mercaptan having a valence of 3 to 6, and a plurality of polymer moieties have two different compositions. Formula (I):

[0016]

[Chemical 1]

Polymers of the formula: are possible. In the above formula (I), polymer moieties having different compositions from PA and PB, for example, the following combinations are possible. PA: PB PMMA: PBA PSt: P (BA / AA) PMMA: P (BA / AA) In the above formula (I), the following formula:

[0018]

[Chemical 2]

The portion represented by is a trivalent to hexavalent mercaptan residue. In the above formula (I), n + m is 3 or more and is equal to or less than the valence of the residue of the mercaptan, and n is 0.
1 or more, preferably 0.5 or more, m is 0.1 or more,
The number is preferably 0.5 or more. If n or m is less than the above value, the desired sufficient performance may not be obtained. The first α, β-unsaturated monomer has at least one high glass transition point type polymer selected from the group consisting of homopolymers and copolymers having a glass transition point of 273K or higher, preferably 300K or higher. It is at least one monomer that can form a coalescence. When the glass transition point of the high glass transition point type polymer is below the above range, the pressure-sensitive adhesive does not have sufficient cohesive force, and the cohesive force is greatly reduced due to the transfer of the plasticizer. The first α, β-unsaturated monomer is, for example, at least one selected from the group consisting of styrene, vinyl acetate, acrylonitrile, methacrylonitrile and methyl methacrylate in an amount of 5 to 40% by weight, preferably 10 to Thirty
Wherein wt%, (meth) acrylic acid alkyl ester monomers discussed later is the balance, containing reactive functional groups alpha, beta-unsaturated monomers and copolymerizable alpha, consisting of beta-unsaturated monomers It is at least one selected from the group.

A first mixture containing polyvalent mercaptan and a first α, β-unsaturated monomer is provided. The first mixture is
If necessary, for example, aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; alicyclic hydrocarbons such as cyclohexane; aliphatic hydrocarbons such as hexane and pentane. It may contain an organic solvent. The organic solvent may be a single solvent or a mixed solvent. The number average molecular weight of the acrylic block polymer (a) is 2,000 to 1,000,000, preferably 1
10,000-400,000, more preferably 20,0
It is 00 to 200,000. If the number average molecular weight is less than the above range, the properties as a block polymer may not be exhibited, and if the number average molecular weight exceeds the above range, the viscosity may be high and the handleability may be poor.

When the acrylic block polymer (a) is produced through a first polymerization step and a second polymerization step, which will be described later, it becomes 2
It is possible to have a plurality of polymer moieties having different compositions described above, and to have a plurality of polymer moieties having different compositions of 3 or more by repeating the second polymerization step twice or more. is there. In the first polymerization step, the first α, with the mercapto group of the polyvalent mercaptan as the starting point,
Radical polymerization of β-unsaturated monomer is performed. By this radical polymerization, in each molecule of the polyvalent mercaptan, a product in which one end of the polymer moiety having one composition is bonded to the sulfur residue of one or more mercapto groups is obtained. This product has unreacted mercapto groups. In order to efficiently bind one end of the polymer portion to the sulfur residue, it is preferable not to add an unnecessary polymerization initiator to the polymerization system.

In the adding step, the monomer mixture is added to the reaction mixture obtained by the radical polymerization performed previously to obtain the second mixture. This monomer mixture is capable of forming a polymer that is incompatible with the high glass transition type polymer, and (meth)
Includes alkyl acrylate monomer. here,
"Incompatible" means in the dynamic viscoelasticity measurement of the polymer
Tangent loss (tan δ, storage elastic modulus G ′ and loss elastic modulus G ″
Ratio: tan δ = G ″ / G ′) has two curve peaks
Means to be. That is, (meth) acrylic acid
For polymer of monomer mixture containing alkyl ester monomer
Glass transition above 273K due to low peak
The peak due to the high glass transition type polymer having a dot is
Appears on the high temperature side. On the other hand, "compatible" means this tangent loss.
The loss curve peak is not separated into two and becomes one peak.
Means that.

The monomer mixture used in the addition step is
A (meth) acrylic acid alkyl ester monomer is contained as an essential component, and if necessary, a reactive functional group-containing α, β-
An unsaturated monomer may be further included. The monomer mixture, regardless of whether it further contains a reactive functional group-containing α, β-unsaturated monomer, is an α, β-unsaturated monomer copolymerizable with these monomers. Can be further included. This
Here, the (meth) acrylic acid alkyl ester monomer used to obtain the acrylic block polymer (a) ,
Α, β-Unsaturated monomer containing reactive functional group, and copolymerization
The types and amounts of possible α, β-unsaturated monomers and the composition and amount of the monomer mixture are as described below.

Monomer of (meth) acrylic acid alkyl ester
The body is usually (meth) acrylic used in adhesives
There is no particular limitation as long as it is an acid alkyl ester.
Group having 4 to 18 carbon atoms, for example,
Butyl ( meth) acrylate, Isobuty ( meth) acrylate
Chill, cyclohexyl (meth) acrylate, (meth) a
2-ethylhexyl acrylate, n- (meth) acrylic acid
Octyl, isooctyl (meth) acrylate, (meth)
Lauryl acrylate and stea (meth) acrylate
And at least one selected from the group consisting of
It Used to obtain acrylic block polymer (a)
Amount of (meth) acrylic acid alkyl ester monomer
Is 68-based on the total amount of the monomer mixture used.
It is 99.89% by weight. Alkyl (meth) acrylate
If the amount of the ester monomer is out of the above range, as an adhesive
There is a possibility that the flexibility and tack of the above may not be obtained.

To obtain the acrylic block polymer (a)
The monomer mixture used in the
It may further include a functional group-containing α, β-unsaturated monomer.
It The α, β-unsaturated monomer containing a reactive functional group is a carbohydrate.
Xyl group-containing α, β-unsaturated monomer, hydroxyl group-containing α, β
At least one selected from the group consisting of unsaturated monomers
Is. The carboxyl group-containing α, β-unsaturated monomer is
If it is an α, β-unsaturated monomer having a carboxyl group,
There is no particular limitation, for example, acrylic acid, methacrylic acid,
Itaconic acid, crotonic acid, maleic anhydride, maleic acid
Selected from the group consisting of unsaturated carboxylic acids such as
There is one. Acrylic block polymer (a)
To obtain a carboxyl group-containing α, β-unsaturated monomer
When using, a carboxyl group-containing α, β-unsaturated simple
The amount of monomer is based on the total amount of the monomer mixture used.
For example, 0.1 to 10% by weight, preferably 2 to 8%
The amount is%. Carboxyl group-containing α, β-unsaturated monomer
If the amount is less than 0.1% by weight, the cohesive force of the adhesive will be insufficient.
May be added, and if it exceeds 10% by weight, cohesive force
May become too high and the adhesive strength may be reduced.

The hydroxyl group-containing α, β-unsaturated monomer is hydroxyl
There is no particular limitation as long as it is an α, β-unsaturated monomer having a group.
However, for example, 2-hydroxyethyl (meth) acrylate
2-hydroxypropyl (meth) acrylate, (me
Data) polycaprolactone of acrylic acid 2-hydroxy Shiechiru
Ton modified product (Product name: Praxel F series (Daicel
Chemical Industry Co., Ltd.)) and other hydroxyl group-containing polymerizable monomers
At least one selected from the group consisting of Ak
To obtain a ril-based graft polymer (a), hydroxyl group-containing α,
When using a β-unsaturated monomer, hydroxyl group-containing α, β-
The amount of unsaturated monomer is the total amount of the monomer mixture used.
With respect to, for example, 0.01 to 2% by weight, preferably
It is 0.1 to 1% by weight. Hydroxyl group containing α, β-unsaturated
If the amount of the monomer is less than 0.01% by weight, the crosslinking point will be insufficient.
As a result, the crosslink density is insufficient and the cohesive force is insufficient.
However, if it exceeds 2% by weight, the crosslink density becomes high.
Or the cohesive strength becomes too high and the adhesive strength decreases.
There is.

To obtain the acrylic block polymer (a)
The monomer mixture used for is a (meth) acrylic acid
Contains a kill ester monomer as an essential component, and has a reactive functionality.
Whether to further contain a group-containing α, β-unsaturated monomer
However, α, β-unsaturation copolymerizable with these monomers
It may further include a monomer. Copolymerizable α, β
-The unsaturated monomer is not particularly limited, for example,
For example, aromatic α, β such as styrene and α-methylstyrene
-Unsaturated monomers; vinyl acetate, vinyl propionate, etc.
Vinyl ester of N; vinylpyrrolidone, acryloyl
N group-containing α, β-unsaturated monomers such as rumorpholine;
Α, β-Unsaturated nitriles such as (meth) acrylonitrile
Le; (meth) acrylamide, N-methylol acrylic
Selected from the group consisting of unsaturated amides such as amides
At least one is mentioned. Acrylic block polymerization
The copolymerizable α, β-unsaturated used to obtain body (a)
The amount of saturated monomer varies depending on tack and adhesion and cohesion.
The total amount of monomer mixture used
On the other hand, it is, for example, 0 to 20% by weight. Copolymerizable
Polymerization occurs when the amount of α, β-unsaturated monomer exceeds 20% by weight.
The body (a) may become hard and the adhesive strength may decrease.

To obtain an acrylic block polymer (a)
The composition of the monomer mixture used for
From the balance of the above, the Tg of the polymer (a) is 200 K to 240
It is preferable to use them in combination so as to obtain K. A
The monomer used to obtain the Kuryl block polymer (a)
The amount of the monomer mixture is the same as that of the monomer mixture and the high glass transition point type.
For example, 60 to 60 parts by weight based on the total of 100 parts by weight of the polymer.
95 parts by weight, preferably 70 to 90 parts by weight. Unit quantity
When the amount of the body mixture exceeds 95 parts by weight, that is, high amount of
If the amount of the transition point type polymer is less than 5 parts by weight, the plasticizer
The decrease in cohesive force due to the migration of may be remarkable. Also,
If the amount of the monomer mixture is less than 60 parts by weight, that is, high
Adhesion occurs when the amount of glass transition point polymer exceeds 40 parts by weight.
The physical properties as an agent may be significantly reduced.

In the second polymerization step, radical polymerization of the monomers contained in the second mixture is carried out. If necessary, the unreacted monomer component can be removed from the reaction mixture containing the product of the radical polymerization previously carried out, or
Unreacted monomer components may be left without being removed and used in the radical polymerization to be performed next. Subsequent radical polymerization is carried out starting from all or part of the remaining mercapto groups of the polyvalent mercaptan. A product is obtained in which one end of the polymer moiety having another composition is bonded to the sulfur residue of the starting mercapto group. This product may have unreacted mercapto groups.
In this case, the second polymerizing step is repeated twice to introduce a polymer portion having a third different composition, and the second polymerizing step is repeated three times to produce the third and fourth polymer parts.
The polymer moieties having different compositions can be introduced, and the polymer moieties having different compositions can be introduced each time the number of repetitions of the second polymerization step is increased.

The first and second polymerization steps for producing the acrylic block polymer (a) can be carried out by the usual radical polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization. In order to obtain an inexpensive polymer, a bulk polymerization method containing no excess volatile component is preferable. The polymerization temperature is preferably 30 to 200 ° C., more preferably 100 to 1 which enables stable bulk polymerization without using a polymerization initiator.
It is 50 ° C. A radical polymerization initiator which is usually used in polymerization for producing an acrylic block polymer (a) (for example, 2,
2'-azobisisobutyronitrile, 2,2'-azobiscyclohexanecarbonitrile and other azo-based polymerization initiators; benzoyl peroxide and other peroxide-based polymerization initiators, etc.) can be used. Usually, 1/3 or less of polyvalent mercaptan, preferably 1/10 or less, more preferably not used. When the polymerization initiator is used in a larger amount than the above ratio, a large amount of the polymer extended from the polymerization initiator is generated in addition to the polymer portion extended from the polyvalent mercaptan which gives the block polymer, and the production efficiency of the block polymer is increased. And the stability of bulk polymerization, which is an industrially inexpensive manufacturing method, deteriorates, a runaway reaction occurs, and in the worst case, there is a risk of explosion.

As the procedure for producing the acrylic block polymer (a) , radical polymerization of the first α, β-unsaturated monomer is carried out starting from the mercapto group of the polyvalent mercaptan, and the polymerization rate is 50%. % Or more, preferably 80% or more, an acrylic block polymer (a) can be obtained by adding and polymerizing a monomer mixture containing a (meth) acrylic acid alkyl ester monomer. . The polymerization rate of the radical polymerization performed first is 50% or more because the properties of the polymer that forms the block even if the subsequent polymerization is performed without removing the unsaturated monomer remaining after the polymerization. Is to be as different as possible. Therefore, it is possible to volatilize and remove the remaining unsaturated monomer after the first polymerization step. Further, if each radical polymerization is terminated by addition of a polymerization inhibitor, it is possible to prevent the polymer portion having a different composition from being connected to the tip of the polymer portion thus formed by the subsequent radical polymerization.

By carrying out the polymerization in multiple stages as described above, the acrylic block polymer (a) composed of a combination of three or more kinds of polymers can be obtained. The organic solvent used in the adhesive composition of the present invention is not particularly limited as long as it is liquid substance A acrylic-based block copolymer (a) can be dissolved and / or dispersed, for example, toluene, and xylene Aromatic hydrocarbons, esters such as ethyl acetate and butyl acetate, alicyclic hydrocarbons such as cyclohexane, and ketones such as acetone and methyl ethyl ketone,
It is a single solvent or a mixed solvent of two or more selected from the group consisting of aliphatic hydrocarbons such as hexane and pentane.
The amount of the organic solvent is, for example, 100 to 400 parts by weight, preferably 150, relative to 100 parts by weight of the acrylic polymer.
~ 350 parts by weight. If it is less than the above range, the viscosity becomes too high, which may cause difficulty in coating work, and if it exceeds the above range, the viscosity may be too low and coating may not be possible.

The adhesive composition of the present invention, A acrylic-based block copolymer (a) is a reactive functional group-containing alpha, made using a monomer mixture containing β- unsaturated monomer in case of,
A crosslinking agent can be further included. The cross-linking agent has at least two functional groups capable of reacting with the reactive functional groups of the acrylic polymer per molecule. As the crosslinking agent used in the present invention, a polyfunctional epoxy compound, a polyfunctional melamine compound, a polyfunctional isocyanate compound, a metal-based crosslinking agent,
Examples thereof include aziridine compounds. In particular, a polyfunctional isocyanate compound is preferable in the reaction with a hydroxyl group and a carboxyl group.

The polyfunctional epoxy compound is not particularly limited as long as it is a compound having two or more epoxy groups per molecule. For example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether,
1,6-hexanediol diglycidyl ether, bisphenol A / epichlorohydrin type epoxy resin,
N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N-diglycidylaniline, N, N-diglycidyltoluidine And so on,
They may be used alone or in combination of two or more.

The polyfunctional melamine compound is
There is no particular limitation as long as it is a compound having two or more of methyl roll group, alkoxymethyl group and imino group,
For example, hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxymethyl melamine, hexapentyloxymethyl melamine, etc. are mentioned, and they are used individually or in combination of two or more. The polyfunctional isocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups per molecule, for example, tolylene diisocyanate (TDI),
4,4'-diphenylmethane diisocyanate (MD
I), hexamethylene diisocyanate, xylylene diisocyanate, metaxylylene diisocyanate,
Isocyanate compounds such as 1,5-naphthalenediisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate; Burette polyisocyanate compounds such as Sumidule N (Sumitomo Bayer Urethane Co.); Desmodur IL, H
L (manufactured by Bayer AG), polyisocyanate compound having an isocyanurate ring such as Coronate EH (manufactured by Nippon Polyurethane Industry Co., Ltd.); adduct poly such as Sumidule L (manufactured by Sumitomo Bayer Urethane Co., Ltd.) Examples thereof include isocyanate compounds and adduct polyisocyanate compounds such as Coronate L (manufactured by Nippon Polyurethane Co.). These can be used alone,
Two or more kinds can be used in combination. It is also possible to use a blocked isocyanate in which the isocyanate group of these polyvalent isocyanate compounds is inactivated by reacting with a masking agent having active hydrogen.

Examples of the metal-based cross-linking agent include metals such as aluminum, zinc, cadmium, nickel, cobalt, copper, calcium, barium, titanium, manganese, iron, lead, zirconium, chromium and tin, acetylacetone, methyl acetoacetate and acetoacetate. Examples thereof include metal chelate compounds coordinated with ethyl acetate, ethyl lactate, methyl salicylate and the like. These may be used alone or in combination of two or more. Examples of the aziridine compound include N,
N'-hexamethylene-1,6-bis (1-aziridinecarboxamide), trimethylolpropane-tri-
β-aziridinyl propionate, bisisophthaloyl-1- (2-methylaziridine), tri-1-aziridinylphosphine oxide, N, N′-diphenylethane-4,4′-bis (1 -Aziridinecarboxamide) and the like. These may be used alone or in combination of two or more.

The amount of the crosslinking agent used is, for example, 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the acrylic polymer (a ) . If the amount of the cross-linking agent is less than 0.1 part by weight, the cross-linking point may be insufficient, so that the cross-linking density may be insufficient and the cohesive force may be insufficient.
If it exceeds 10 parts by weight, the crosslink density becomes too high,
The adhesive strength may decrease. The composition for pressure-sensitive adhesives of the present invention may contain a tackifier commonly used for pressure-sensitive adhesives, if necessary. Examples of the tackifier include (polymerized) rosin type, (polymerized) rosin ester type, terpene type, terpene phenol type, coumarone type, coumarone indene type,
Styrene resin type, xylene resin type, phenol resin type,
Examples thereof include petroleum resin-based tackifiers. These are 1
They may be used alone or in combination of two or more. The amount of the tackifier is 100 parts by weight of the acrylic polymer (a ) ,
For example, it is 5 to 100 parts by weight, preferably 10 to 50 parts by weight. If it is less than the above range, the adhesiveness to an adherend may not be improved, and if it exceeds the above range, tack may be reduced and adhesive strength may be lowered.

The composition for pressure-sensitive adhesives of the present invention contains fillers, pigments, diluents, anti-aging agents, anti-aging agents, ordinarily used for pressure-sensitive adhesives, whether or not they contain tackifiers. It may contain at least one additive selected from the group consisting of an ultraviolet absorber and an ultraviolet stabilizer. Adhesive composition of the present invention, for example, sticky products in a manner which will be described later
And used to make laminated products . Sticky products [sticky products and laminating products The present invention is provided with a soft PVC pressure-sensitive adhesive layer formed using the adhesive composition of the present invention to at least one surface of the support, soft if laminated to polyvinyl chloride moldings
Those Wasera is. The support may be a film or a film.
At least one selected from the table, tape and wallpaper
Can be mentioned.

In the bonded product of the present invention, two adherends are
Layer composed of the composition for pressure-sensitive adhesive of the present invention (pressure-sensitive adhesive for soft vinyl chloride
Layers) are laminated together. These two covers
At least one of the adhesives is a soft vinyl chloride base material
is there. The pressure-sensitive adhesive layer for soft vinyl chloride is, for example, an acrylic block.
Lock polymer (a) and acrylic block polymer (a)
The present invention containing a dissolved and / or dispersed organic solvent
Apply the bright adhesive composition to the coated object for drying and crosslinking
And a cross-linking step . Acrylic block polymer (a) each monomer mixture used in the polymerization process for producing, as previously described, reactive functional group-containing alpha, Rukoto further comprise β- unsaturated monomer mer Can
It was Then, when the monomer mixture containing such reactive functional group-containing alpha, beta-unsaturated monomer, the pressure-sensitive adhesive composition, a functional group capable of reacting with the reactive functional groups of at least 2 can Rukoto further include a number having crosslinking agent
It was

Therefore, in the above-mentioned crosslinking step, the organic solvent is removed from the pressure-sensitive adhesive composition by applying such a pressure-sensitive adhesive composition to an article to be coated and drying it, and the acrylic block It can also be carried out by crosslinking the polymer (a)
it can. As the article to be coated, for example, a separator, a support, a base material, etc. described later are appropriately used. Crosslinking of A acrylic-based block copolymer (a) is performed, for example, by high-temperature accelerated crosslinking to facilitate the reaction at ambient temperature crosslinking and, 40 to 50 ° C. in a constant temperature room to stand more than one week at room temperature.

[0041] When A acrylic-based block copolymer (a) is a reactive functional group-containing alpha, made using a monomer mixture containing β- unsaturated monomer, reactive with the acrylic polymer It is crosslinked by reaction with a crosslinking agent having at least two functional groups capable of reacting with the functional group. The crosslinking agent used here is
It is the same as the crosslinking agent used in the pressure-sensitive adhesive composition. The cross-linking conditions may be appropriately set depending on the cross-linking agent used. Adhesive products of the present invention may further comprise a separator attached to one or both sides of the soft PVC pressure-sensitive adhesive layer. Adhesive products of the present invention comprises two flexible PVC pressure-sensitive adhesive layer, a support sandwiched between the soft PVC pressure-sensitive adhesive layer, the soft PVC pressure-sensitive adhesive layer, opposite the support It may further include a separator attached to one surface.

The adhesive product of the present invention may further comprise a separator attached to one side of the soft vinyl chloride adhesive layer and a base material attached to the other side of the soft vinyl chloride adhesive layer. The base material is, for example, a soft polyvinyl chloride base material. Examples of the separator used in the present invention include a paper base material whose surface is directly release-treated with a release agent such as silicone, a laminated film in which a polyethylene film is laminated on the back surface of the release-treated paper base material, and a polyester. -A plastic film such as polyethylene or polypropylene is used. Adhesive products of the present invention,
For example, an adhesive sheet, an adhesive tape, an adhesive label, a double-sided tape, etc. for soft PVC; or a soft PVC adhesive sheet, a soft PVC adhesive tape, a soft PVC adhesive label, etc.

The adhesive product of the present invention will be made by the following method, not limited to the manufacturing method. On one surface of the separator, a pressure-sensitive adhesive composition of the present invention, which was coated with at least an acrylic polymer (a ), a cross-linking agent and an organic solvent, was dried and then formed on the separator surface. The pressure-sensitive adhesive layer is superposed on one surface of another separator, a base material described later or a support described later, and pressed (for example, 1 to
(At a pressure of 5 kg / cm ² ) and transfer. It is also possible to superimpose the pressure-sensitive adhesive layers formed on the surfaces of the two separators on both sides of the support described later and apply pressure in the same manner to transfer them. On one surface or both surfaces of the support, the adhesive composition of the present invention, which contains at least the acrylic polymer (a ), the cross-linking agent and the organic solvent, is applied and dried. , Glue the separator so as to cover the obtained adhesive layer.

The dry thickness of the pressure-sensitive adhesive layer is, for example, 10 to 1
It is 00 μm. Drying is performed, for example, by leaving it in a hot air dryer at 70 to 100 ° C. for 2 to 10 minutes. The adhesive composition of the invention and sticky product is applied to a soft polyvinyl chloride molding. The soft polyvinyl chloride molded article is an adherend to which a pressure-sensitive adhesive layer is attached, and can be, for example, a sheet, a tape, a wallpaper, a foam (foam) or the like. Adhesive products of the present invention can support is a soft polyvinyl chloride molding.

[0045]

[Action] In A acrylic-based block copolymer of the pressure-sensitive adhesive composition of the present invention (a), the portion of the high glass transition temperature type polymer,
It is dispersed in the polymer portion of the monomer mixture containing the (meth) acrylic acid alkyl ester monomer, and the high glass transition type polymer portion and the polymer portion of the monomer mixture are chemically Are combined together. This means that a system in which a polymer of a monomer mixture containing a (meth) acrylic acid alkyl ester monomer and a high glass transition type polymer are simply blended tends to separate in a solution state. This can be verified from the fact that the system of the present invention does not show this tendency.
The high glass transition type polymer part has a micro-domain structure with respect to the polymer part of the monomer mixture containing the (meth) acrylic acid alkyl ester monomer, and the physical property of the polymer part is adhesive. Since it functions as a cross-linking agent, the pressure-sensitive adhesive composition of the present invention forms a pressure-sensitive adhesive exhibiting high cohesive force without impairing the tackiness even when applied to a soft polyvinyl chloride molded article.

[0046]

DETAILED DESCRIPTION FIG. 1 is a cross-sectional view of one embodiment of the adhesive product of the present invention. The sticky product is a double-sided adhesive tape 5, the support 1, soft PVC pressure-sensitive adhesive layer 2, a separator 3
Have. Soft PVC pressure-sensitive adhesive layer 2, crosslinked acrylic copolymer pressure-sensitive adhesive composition was made by a manufacturing method including a drying and cross-linking process of the present invention (A acrylic-based block copolymer (a) is cross-linked Which is the main ingredient, and is formed on both sides of the support 1. The separator 3 is, for example, a release paper, and is attached to this surface so as to cover one surface of the soft vinyl chloride adhesive layer 2. One surface of the pressure-sensitive adhesive layer 2 is the surface opposite to the one surface attached to the support 1.

The support is, for example, conventionally known paper, plastic film, foam sheet, non-woven fabric or the like. Adhesive products of the present invention, the support is a soft polyvinyl chloride shaped article (e.g., film, sheet, tape, wallpaper) can be a. Figure 2 is a cross-sectional view of another exemplary embodiment of the adhesive product of the present invention. The sticky product is 6 (double-sided adhesive tape without support) centerless double-sided adhesive tape, with soft PVC pressure-sensitive adhesive layer 2, a separator 3.
Soft PVC pressure-sensitive adhesive layer 2, crosslinked acrylic copolymer pressure-sensitive adhesive composition was made by a manufacturing method including a drying and cross-linking process of the present invention (A acrylic-based block copolymer (a)
That is cross-linked) is included as a main agent. Separator 3
Is a release paper, for example, and is attached to both sides of the soft vinyl chloride adhesive layer 2 so as to cover both sides.

[0048] Figure 3 is a cross-sectional view of another exemplary embodiment of the adhesive product of the present invention. The sticky product, soft PVC pressure-sensitive adhesive layer 2, a separator 3, having a substrate 4. Soft PVC pressure-sensitive adhesive layer 2, crosslinked acrylic copolymer pressure-sensitive adhesive composition was made by a manufacturing method including a drying and cross-linking process of the present invention (A acrylic-based block copolymer (a) is cross-linked Tamono) as the main ingredient. The separator 3 is, for example, release paper, and is attached to one surface of the soft vinyl chloride adhesive layer 2 so as to cover the one surface. The base material 4 is a soft polyvinyl chloride base material (eg, film, sheet, tape, wallpaper).

[0049] Figure 4 is a cross-sectional view of another exemplary embodiment of the adhesive product of the present invention. The sticky product, soft PVC pressure-sensitive adhesive layer 2, a separator 3, having a substrate 7. Soft PVC pressure-sensitive adhesive layer 2, crosslinked acrylic copolymer pressure-sensitive adhesive composition was made by a manufacturing method including a drying and cross-linking process of the present invention (A acrylic-based block copolymer (a) is cross-linked Tamono) as the main ingredient. The separator 3 is, for example, release paper, and is attached to one surface of the soft vinyl chloride adhesive layer 2 so as to cover the one surface. Substrate 7, for example, A Le Mifoiru; polyethylene, polyolefins such as polypropylene sheets.

Specific examples of the present invention will be described below together with comparative examples, but the present invention is not limited to the following examples. In the following Examples and Comparative Examples, "parts" and "%" represent "parts by weight" and "% by weight", respectively. Production of pressure-sensitive adhesive composition] - Production Example A 1 - Styrene 200 parts of pentaerythritol tetrakis thioglycolate (PETG) 1.0 parts thermometer, stirrer, Max Blend blade (Sumitomo Heavy Industries, Ltd. Made),
A 2-liter four-necked flask equipped with an inert gas introduction tube, a reflux condenser and a dropping funnel was charged, and polymerization was carried out at 140 ° C. under a nitrogen atmosphere. After 3 hours, 760 parts of butyl acrylate and 40 parts of acrylic acid were added all at once. After a while, it was found that when the internal temperature increased, the reaction mixture became cloudy and the second-stage polymerization was started. The polymerization rate after reacting for 5 hours at the monomer reflux temperature was 99.4%. The residual monomer was removed under reduced pressure, and 1300 parts of toluene was added to the reaction mixture to dissolve it, and the solid content was 36.4.
%, A solution of an acrylic copolymer having a viscosity of 17200 cps was obtained.

[0051] - Production Example A 2 to A 4 and Comparative Production Examples a1
- except that the reaction raw materials and / or reaction conditions were changed as shown in Table 1 by repeating the procedure of Example A 1,
A solution of an acrylic copolymer having the solid content, viscosity and weight average molecular weight shown in Table 1 was obtained. -Comparative Production Example a2-Injecting 252 parts of ethyl acetate with a thermometer, a stirrer, and an inert gas
Four-necked frass with tube, reflux condenser and dropping funnel
The mixture of the monomers shown in Table 2 was placed in this flask.
200 out of 600 were loaded. Flask contents
While stirring the mixture under a nitrogen stream and maintaining it at 80 ° C.
As a polymerization initiator, Niper BMT-K40 (NOF
Polymerization was started by adding 0.48 parts of organic peroxide manufactured by
Let 10 minutes after the start of polymerization, the rest of the monomer mixture
(400 parts) and toluene 183 parts and Niper BMT-K
40 (organic peroxide manufactured by NOF CORPORATION) 1.20 parts
1. The solution was continuously added dropwise over 5 hours.
91 parts of chill, 590 parts of toluene and 2,2'-azobis
(2-methylbutyronitrile) (Japan Hydrazine Industry Co., Ltd.
Made, abbreviated as ABNE) 1.8 parts, and added at 85 ° C.
React for 5 hours, solid content 34.8%, viscosity 5200c
ps (25 ° C, B-type viscometer, the same applies below) for acrylic
A polymer solution was obtained.

-Comparative Production Examples a3 to a7- Reaction raw materials and / or reaction conditions are shown in Tables 2-3.
The procedure of Comparative Production Example a2 was repeated except that the cage was changed.
In return, the solid content, viscosity, and weight average molecular weight shown in Table 3
A solution of a krill-based copolymer was obtained.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

[Table 3]

Example B1- Preparation Coronate L55E (polyisocyanate compound manufactured by Nippon Polyurethane Company: solid content 55) relative to the solution of the acrylic copolymer obtained in Example A1 (solid content 100 parts)
%) Was mixed to prepare an adhesive composition . - Example B2～B 8 and Comparative Examples b1 ~ b6 - except that the solution and the amount of crosslinking agent of the acrylic copolymer was changed as shown in Table 4 by repeating the procedure of Example B1, the pressure-sensitive adhesive composition The thing was made. In the table , TET
RAD-C is 1,3-bis manufactured by Mitsubishi Gas Chemical Co., Inc.
(N, N-diglycidylaminomethyl) cyclohexane
Is. However, TETRAD-C is a solution with a solid content of 5%.
Mixed in.

Example C1-The pressure-sensitive adhesive composition obtained in Example B1 was coated on one surface of a piece of release paper (Fujimori Kogyo Co., Ltd .: 70K-818T / EF) so that the thickness after drying was 50 μm. After coating on 10
It was dried at 0 ° C. for 2 minutes and aged at 23 ° C. for 7 days. Then, the soft polyvinyl chloride sheet having a thickness of 50 μm (made by Okamoto Co., Ltd.) is superposed on one side and pressed, and the pressure-sensitive adhesive composition is transferred to one side of the soft polyvinyl chloride sheet to form a soft vinyl chloride adhesive sheet (with release paper). ) Got. In addition, Example B1
Two pieces of release paper (Fujimori Kogyo Co., Ltd.)
(Made by company: 70K-818T / EF) on each side after drying
Coat to a thickness of 75 μm and at 100 ° C for 3 minutes
After drying, apply the adhesive composition coated surface of two release papers to 1
Overlap on both sides of the non-woven fabric and apply pressure to
Transfer the adhesive composition to both sides and apply a double-sided tape with a thickness of 150 μm.
Loop (with double-sided release paper) was prepared.

[0058] - Example C2～C 8 and Comparative Examples c1 ~ c6 - Repeat steps except that the adhesive composition was changed as shown in Table 4 in Example C1, contact soft PVC adhesive sheet
And double-sided tape was produced. - Comparative Example c7 - were prepared for comparison the commercially available soft PVC double-sided tape (Sekisui Chemical product name double tack tape ♯577 Co., Ltd.). - Comparative Example c8 - were prepared for comparison the commercially available soft PVC double-sided tape (Nitto Denki Kogyo Co., Ltd. under the trade name double-sided adhesive tape No.501M).

Comparative Example c9 A commercially available double-sided tape for soft vinyl chloride (double-sided adhesive tape No. 5000CX, trade name, manufactured by Nitto Denki Kogyo Co., Ltd.) was prepared for comparison. Regarding the soft vinyl chloride adhesive sheets and the double-sided tapes obtained in Examples and Comparative Examples, JIS-Z0
237 (1991) to measure the holding force and adhesive force,
The results are shown in Table 4 .

As for the holding power, the stainless steel plate (SUS30
The adhesive sheet of 20 mm × 20 mm is attached to 4), and 20 minutes after the attachment, the temperature is kept at 80 ° C., and after 20 minutes, a load of 1 kg is applied to drop the sheet, or
The amount of deviation measured 24 hours after applying the load is shown. The adhesive strength of the pressure-sensitive adhesive sheet is shown as an initial value and a value after heating is promoted. The initial value is that a 25 mm width adhesive sheet is attached to an aluminum plate (JI) in an atmosphere of 23 ° C and 65% RH.
SA1050P: thickness 1 mm) was reciprocated once with a 2 kg rubber roller, and after 25 minutes, the strength when peeled in the 180 ° direction at a speed of 300 mm / min was measured. The value after heating acceleration is as follows. The pressure-sensitive adhesive sheet is left in an atmosphere of 80 ° C. for 3 days, further left in an atmosphere of 23 ° C. and 65% RH for 2 hours, cut into a width of 20 mm, and then cut into an aluminum plate.
A rubber roller of kg was reciprocated 3 times to bond them, and after 24 hours, the strength when peeled in a 180 degree direction at a speed of 300 mm / min was measured.

The adhesive strength of the double-sided tape is shown by the initial value and the value after heating is promoted. The initial value is 23 ° C., 65% RH atmosphere, PET film that has been subjected to corona discharge treatment is lined from one side of the double-sided tape, the double-sided tape is cut into a width of 20 mm, and then soft salt with a thickness of 2 mm is used. Bisheet (Okamoto Co., Ltd., # 480, plasticizer 50 phr, back side fixed to aluminum plate with commercial double-sided adhesive tape)
2kg rubber roller back and forth 3 times
After 5 minutes, the strength at the time of peeling in the direction of 180 degrees at a speed of 300 mm / min was measured. The value after heating acceleration is a soft vinyl sheet with a thickness of 2 mm, which is a double-sided tape lined with a PET film that has been subjected to a corona discharge treatment and cut to a width of 20 mm (Okamoto Co., Ltd., # 480, plasticizer 50 phr, the back side is commercially available). Aluminum plate fixed with double-sided adhesive tape)
2kg of rubber roller back and forth 3 times to stick together, 8
Leave in 0 ℃ atmosphere for 3 days, then 23 ℃, 65% R
The strength at the time of peeling in the direction of 180 degrees at a speed of 300 mm / min after standing for 2 hours in the atmosphere of H was measured.

[0062]

[Table 4]

[0063] As seen in Table 4, an embodiment of the present invention, pressurized
Decrease in adhesive strength due to heat acceleration, and soft PVC
The decrease in cohesive force was also observed in comparison with the comparative example even when the plasticizer was transferred from
It is considerably suppressed in comparison. The glass transition temperature (Tg: K) of the produced acrylic copolymer was calculated according to the following equation using the following data. Acrylic acid: 379 (K) Methyl acrylate: 281 (K) Ethyl acrylate: 251 (K) Butyl acrylate: 219 (K) 2-Ethylhexyl acrylate: 203 (K) 2-Hydroxyethyl acrylate: 258 ( K) Methyl methacrylate: 378 (K) Vinyl acetate: 305 (K) Acrylonitrile: 398 (K) Styrene: 373 (K)

[0064]

[Equation 1]

[0065]

The composition for pressure-sensitive adhesives of the present invention has the above-mentioned characteristics.
Since it contains a fixed acrylic block polymer (a) and an organic solvent, it has an excellent balance of cohesive strength and adhesive strength, does not easily cause a decrease in cohesive strength due to migration of plasticizer, and is practical for adhesive products for soft PVC. It can be used to make an adhesive layer for soft PVC, which has an excellent shelf life. When the monomer mixture further contains a reactive functional group-containing α, β-unsaturated monomer, the pressure-sensitive adhesive composition of the present invention contains a crosslinking agent having a functional group that reacts with these reactive functional groups. It has the further advantage that it can be used to control the cohesive strength at will.

The adhesive composition of the present invention contains at least a functional group capable of reacting with a reactive functional group when the monomer mixture further contains a reactive functional group-containing α, β-unsaturated monomer. When it further contains two crosslinking agents, it has the advantage that a sufficient amount of cohesive force can be obtained with a small amount of crosslinking agent. Adhesive products of the present invention is provided with the soft PVC pressure-sensitive adhesive layer formed using the adhesive composition of the present invention, bonding to the soft polyvinyl chloride moldings
When al is, excellent balance of cohesive strength and adhesive strength, it causes less decrease in the cohesive force due to plasticizer migration, and has excellent practical importance shelf life of soft PVC adhesive products.

[Brief description of drawings]

1 is a cross-sectional view of one embodiment of the adhesive product of the present invention.

2 is a cross-sectional view of one embodiment of the adhesive product of the present invention.

3 is a cross-sectional view of one embodiment of the adhesive product of the present invention.

4 is a cross-sectional view of one embodiment of the adhesive product of the present invention.

[Explanation of symbols]

1 support 2 Adhesive layer 3 separator 4 base material 5 Double-sided adhesive tape 6 coreless double-sided adhesive tape

Front Page Continuation (72) Inventor Maywa Baba 5-8 Nishimitabicho Suita City, Osaka Prefecture Nippon Shokubai at Suita Works (72) Inventor Masatoshi Yoshida 5-8 Nishimitabicho Suita City, Osaka Prefecture Incorporated Nippon Catalyst Co., Ltd., Polymer Research Laboratory (72) Inventor Nobuhiro Kobayashi No. 5-8 Nishimitabicho, Suita City, Osaka Prefecture Incorporated Nippon Catalyst Co., Ltd. Polymer Research Laboratory (56) Reference JP-A-64-24879 (JP, A) ) JP-A-54-21485 (JP, A) JP-A-5-17733 (JP, A) JP-A-7-90227 (JP, A) JP-A-56-34777 (JP, A) JP-A-3- 192181 (JP, A) JP 57-102975 (JP, A) JP 60-4576 (JP, A) JP 4-68074 (JP, A) JP 1-139640 (JP, A) JP-A 2-1786 (JP, A) JP-A 63-260976 (JP, A) JP-A 4-142381 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C09J 4/00-201/10 C08F 2/00-4/82 C08F 251/00-297/08

Claims (4)

(57) [Claims] 1. A pressure-sensitive adhesive composition comprising an acrylic block polymer and an organic solvent in which the acrylic block polymer is dissolved and / or dispersed, wherein the acrylic block polymer is a polyvalent mercaptan and 273K. A preparatory step of preparing a first mixture containing a first α, β-unsaturated monomer capable of producing a high glass transition type polymer having the above glass transition point, and mercapto contained in the polyvalent mercaptan. Starting from the group, the first α,
a first polymerization step of radically polymerizing a β-unsaturated monomer to obtain a reaction mixture, and a polymer which is incompatible with the high glass transition type polymer, and which is an alkyl (meth) acrylate Production including an addition step of adding a monomer mixture containing an ester monomer to the reaction mixture to obtain a second mixture, and a second polymerization step of radically polymerizing the monomer contained in the second mixture A composition for a pressure-sensitive adhesive for soft PVC, which is an acrylic block polymer produced by the method. 2. Acrylic block polymer and this acrylic
Organic in which a block polymer is dissolved and / or dispersed
In the composition for pressure-sensitive adhesive containing a solvent, The acrylic block polymer, It has polyvalent mercaptan and glass transition temperature above 273K.
The first α, β- that can form a high glass transition type polymer
Preparatory step of preparing a first mixture containing an unsaturated monomer
And a part of the mercapto group of the polyvalent mercaptan
Radical of the first α, β-unsaturated monomer starting from
The first polymerization step to obtain a reaction mixture
Form polymers that are incompatible with high glass transition polymers
And (meth) acrylic acid alkyl ester monomer
To the reaction mixture and adding a second mixture to the reaction mixture.
And an addition step of obtaining a polyvalent mercaptan
Starting from all or part of the mercapto group of the reaction
Radical polymerization of the monomer contained in the second mixture is performed.
Made by a manufacturing method including a second polymerization step, The sulfur residue of the polyvalent mercaptan was added to the first polymerization step.
One end of the polymer part obtained and the second polymerization step
The resulting polymer portion having one end bound to the io C residue
Radially composed of multiple polymer moieties with the same center but different compositions
It is an acrylic block polymer having a structure extending in the
The A composition for a pressure-sensitive adhesive for soft PVC, which is characterized in that: 3. A film, sheet, also claim 1 on at least one surface of a support consisting of either tape and wallpaper
Is a pressure-sensitive adhesive product which comprises a pressure-sensitive adhesive layer for soft vinyl chloride formed by using the pressure-sensitive adhesive composition according to 2, and is bonded to a soft polyvinyl chloride molded article. 4. A bonded product comprising two adherends, at least one of which is a soft polyvinyl chloride base material, adhered via a layer comprising the composition for pressure-sensitive adhesive according to claim 1 or 2 .