JP2017206586A - Adhesive and adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive and an adhesive tape exhibiting high moisture vapor transmission and good keratin detachment resistance, especially an adhesive and an adhesive tape excellent in adhesiveness to an olefinic substrate.SOLUTION: There is related an adhesive agent containing a copolymer (A) containing a constitutional unit derived from a monomer represented by at least following (a-1), (a-2) and (a-3) and a plasticizer (B), with 1-50 pts.wt. of the plasticizer (B) based on 100 pts.wt. of the copolymer (A) and containing following content in the all monomer constituting the copolymer (A). (a-1) alkyl (meth)acrylate of 10-49 wt.%. (a-2) (meh)acrylate having a hydroxyl group or aryl ether having a hydroxyl group of 0.01-10 wt.%. (a-3) alkoxyalkyl (meth)acrylate of 50-80 wt.%.SELECTED DRAWING: None

Description

  The present invention relates to an adhesive and an adhesive tape. More specifically, the present invention relates to a pressure-sensitive adhesive and a pressure-sensitive adhesive tape that are suitably used for medical skin application.

  The adhesive tape for skin application generally has a configuration in which an adhesive layer containing a drug is formed on one side of a flexible support as required. The function of the adhesive tape for skin application is to prevent the entry of water, bacteria, viruses, etc. from outside into the body, and at the same time, the moisture permeability (also called water vapor permeability) that evaporates moisture from perspiration from the skin ) Is also required. When the moisture permeability is inferior, sweat accumulates between the skin and the adhesive layer, and the skin is liable to cause skin disorders such as fog and swelling. In addition, the adhesive strength is reduced and the tape is easily peeled off from the skin. If the adhesive force is too strong to prevent peeling, the hair on the body surface is peeled off at the time of peeling, keratin peeling occurs, or the pressure-sensitive adhesive remains on the skin surface.

  In the past, urethane-based nonwoven fabrics that follow the movement of the curved surface, expansion and contraction, twisting, etc. of the skin have been used, but in recent years there has been an increasing need for the use of olefin-based nonwoven fabrics for the purpose of fixing the affected area. It is coming. As a result, in order to increase moisture permeability, the copolymerization ratio of the functional group-containing monomer must be increased. However, when the olefin-based nonwoven fabric is used as the base material, there is a problem that the base material adhesion is insufficient. is there.

  Patent Document 1 discloses a medical pressure-sensitive adhesive that has high water vapor permeability, is difficult to peel off, and has an appropriate adhesive force that does not damage the skin when it is peeled off, and such an appropriate adhesive force durability and appropriate cohesive force. The medical adhesive containing the polymer which contains more than 50 wt% of the units derived from the alkoxyalkyl acrylate whose homopolymer has a glass transition temperature (Tg) of −35 ° C. or less is disclosed. However, a material having a high water vapor transmission rate has a weak adhesive force, and a material having a high water adhesion strength tends to have a low water vapor transmission rate, and there is a problem in that the water vapor transmission rate and the adhesive force are not compatible.

  Patent Document 2 discloses a pressure-sensitive adhesive composition for skin patch that can be optimally used for external applications such as the medical hygiene field, sports field, and beauty health field, and (meth) acrylic acid alkyl ester as a pressure-sensitive adhesive tape for skin patch. Acrylic copolymer obtained from a monomer mixture containing 40 to 80% by weight, alkoxy group-containing ethylenically unsaturated monomer 10 to 60% by weight, carboxyl group-containing ethylenically unsaturated monomer 1 to 10% by weight A pressure-sensitive adhesive composition containing 20 to 120 parts by weight of a carboxylic acid ester that is liquid or pasty at room temperature is disclosed in 100 parts by weight of the coalescence. However, although it is excellent in water-resistant adhesive strength for suppressing peeling during sweating, the moisture permeability is low and the adhesion to an olefin-based substrate has not been considered.

JP-A-7-275340 JP 2002-065841 A

As described above, an adhesive having both moisture permeability and adhesive strength is not known, and an adhesive and an adhesive tape capable of satisfying these characteristics have been demanded. Furthermore, for medical use such as skin sticking, there are also matters such as good peelability with little exfoliation to the skin and excellent adhesiveness even when the base material is an olefin-based nonwoven fabric, and less adhesive residue on the skin. Desired.
Therefore, the problem to be solved by the present invention is to provide a pressure-sensitive adhesive and a pressure-sensitive adhesive tape that exhibit high moisture permeability and good exfoliation resistance. Furthermore, in addition to the said subject, it is providing the adhesive and adhesive tape which are excellent in olefin type-base-material adhesiveness.

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.
That is, the embodiment of the present invention includes at least a copolymer (A) and a plasticizer (B) containing structural units derived from monomers represented by the following (a-1), (a-2) and (a-3): The pressure-sensitive adhesive comprises 1 to 50 parts by weight of a plasticizer (B) with respect to 100 parts by weight of the copolymer (A), and the copolymer (A) is a copolymer. It is related with the adhesive which contains the following content in all the monomers which comprise (A).
(A-1) Alkyl (meth) acrylate 5 to 49% by weight
(A-2) (Meth) acrylate having a hydroxyl group or allyl ether having a hydroxyl group 0.01 to 10% by weight
(A-3) Alkoxyalkyl (meth) acrylate 50-80% by weight

  Moreover, embodiment of this invention is (a-1) alkyl (meth) acrylate 15 in which the alkyl (meth) acrylate has a C4-C8 alkyl group in all the monomers which comprise a copolymer (A). It is related with the said adhesive containing 5 to 34 weight% of alkyl (meth) acrylates which have -44 weight% and a C9-22 alkyl group.

  Moreover, the embodiment of this invention is related with the said adhesive whose copolymer (A) is a copolymer (A) which does not contain the structural unit derived from the monomer which has an acidic group.

  In addition, the embodiment of the present invention relates to the pressure-sensitive adhesive, wherein the copolymer (A) further contains a structural unit derived from a monomer having an amide bond.

  Further, in an embodiment of the present invention, the copolymer (A) further comprises (a-4) a structural unit derived from alkoxy polyalkylene glycol mono (meth) acrylate or alkoxy polyalkylene glycol allyl ether in an amount of 0.1 to 25 weight. % Of the pressure-sensitive adhesive.

  Moreover, the embodiment of this invention is related with the said adhesive whose weight average molecular weights of a copolymer (A) are 400,000 or more and less than 2 million.

  Further, in an embodiment of the present invention, the pressure-sensitive adhesive is such that the plasticizer (B) is at least one selected from the group consisting of fatty acid esters, epoxidized oil esters, polyalkylene glycol esters, phosphate esters and citrate esters. About.

  Moreover, the embodiment of this invention is further related with the said adhesive containing a hardening | curing agent.

  Moreover, the embodiment of this invention is related with the said adhesive for medical use.

Moreover, the embodiment of the present invention is the production of a pressure-sensitive adhesive that is copolymerized with at least the monomers represented by the following (a-1), (a-2) and (a-3) and then mixed with the plasticizer (B). It is a method, Comprising: It relates to the manufacturing method of the adhesive characterized by copolymerizing by the following content in all the monomers which comprise a copolymer (A).
(A-1) Alkyl (meth) acrylate 5 to 49% by weight
(A-2) (Meth) acrylate having a hydroxyl group or allyl ether having a hydroxyl group 0.01 to 10% by weight
(A-3) Alkoxyalkyl (meth) acrylate 50-80% by weight

  Moreover, the embodiment of this invention is related with the adhesive tape which has the adhesion layer formed from the said adhesive.

  Moreover, the embodiment of this invention is related with the manufacturing method of the adhesive tape which coats the said adhesive to a base material.

  When used for skin application, the pressure-sensitive adhesive and pressure-sensitive adhesive tape obtained by the present invention have high moisture permeability, good exfoliation resistance, and hardly cause skin disorders such as stuffiness and fog. In addition, there is little pain when peeling from the skin, there is no exfoliation, and there is no residue of the adhesive layer on the skin even when an olefin-based substrate is used.

Details of the present invention will be described below. In this specification, “(meth) acryl”, “(meth) acryloyl”, “(meth) acrylic acid”, “(meth) acrylate”, “(meth) acryloyloxy”, and “(meth) allyl” Unless otherwise specified, “acrylic or methacrylic”, “acryloyl or methacryloyl”, “acrylic acid or methacrylic acid”, “acrylate or methacrylate”, “acryloyloxy or methacryloyloxy”, And “allyl or methallyl”.

The acrylic pressure-sensitive adhesive of the present invention is a pressure-sensitive adhesive comprising a copolymer containing monomer units represented by the following (a-1), (a-2), and (a-3). Further, in some cases, (a-4) may be included.
(A-1) alkyl (meth) acrylate (a-2) (meth) acrylate having hydroxyl group or allyl ether having hydroxyl group (a-3) alkoxyalkyl (meth) acrylate

<(A-1) Alkyl (meth) acrylate>
Examples of the alkyl (meth) acrylate that is a monomer represented by (a-1) include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and nonyl (meta ) Acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, and other alkyl (meth) acrylates.
Among these alkyl (meth) acrylates, alkyl (meth) acrylates having 4 to 22 carbon atoms in the alkyl group are preferable, alkyl (meth) acrylates having 4 to 16 carbon atoms in the alkyl group are more preferable, More preferred are alkyl (meth) acrylates having 8 to 14 carbon atoms. In the present specification, the alkyl (meth) acrylate having an alkyl group having 4 to 22 carbon atoms refers to an alkyl (meth) acrylate having 4 to 22 carbon atoms in the alkyl group that does not contain carbon atoms in the (meth) acryloyl group. Means.
The adhesive tape for skin application may get wet with water, and since it has a certain degree of hydrophobicity, it prevents water from entering from the interface between the adhesive tape and the skin and prevents the tape from peeling off from the skin. By using an alkyl (meth) acrylate, the hydrophobicity is enhanced and the skin sticking durability is improved. In particular, adhesiveness and hydrophobicity can be imparted and skin sticking durability can be improved by using one or two or more alkyl (meth) acrylates having 4 to 22 carbon atoms. In order to adjust the hydrophobicity, it is preferable to use two or more alkyl (meth) acrylates having 4 to 22 carbon atoms.

The alkyl (meth) acrylate is preferably 5 to 49% by weight, more preferably 10 to 45% by weight, and still more preferably 15 to 40% by weight, based on all monomers constituting the copolymer. If it is 49% by weight or less, the adhesive strength is not excessively strong and the exfoliation resistance is excellent, and the amount of monomer contributing to moisture permeability can be secured, resulting in good moisture permeability. On the other hand, if it is 5% by weight or more, the adhesiveness to the skin can be secured, and the skin sticking durability is also exhibited.
When two or more alkyl (meth) acrylates having 4 to 22 carbon atoms are used, the alkyl (meth) acrylate having 4 to 8 carbon atoms is 15 to 44% by weight, preferably 15 to 40% by weight, carbon number. Is 9 to 22 alkyl (meth) acrylate is 5 to 34 wt%, preferably 5 to 30 wt%.

<(A-2) (Meth) acrylate having hydroxyl group or allyl ether having hydroxyl group>
Examples of the (meth) acrylate having a hydroxyl group as the monomer represented by (a-2) or the allyl ether having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 3-chloro. Hydroxyl groups such as 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate and 8-hydroxyoctyl (meth) acrylate, polyalkylene glycol mono (meth) acrylate, etc. (Meth) acrylates having an allyl ether having a hydroxyl group such as polyalkylene glycol allyl ether. Among these, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are preferable.

  The (meth) acrylate having a hydroxyl group or the allyl ether having a hydroxyl group is preferably 0.01 to 10% by weight, more preferably 0.1 to 10% by weight, more preferably 0.1 to 10% by weight, based on all monomers constituting the copolymer. 5% by weight is more preferred. If the amount of (meth) acrylate having a hydroxyl group or allyl ether having a hydroxyl group is 0.01% by weight or more, a sufficient cross-linked structure can be formed with the curing agent, and the pressure-sensitive adhesive will not easily remain on the skin. On the other hand, if it is 10% by weight or less, an excessive cross-linked structure can be avoided and adhesiveness to the skin can be ensured.

<(A-3) Alkoxyalkyl (meth) acrylate>
The alkoxyalkyl (meth) acrylate that is the monomer represented by (a-3) is not particularly limited as long as it is a (meth) acrylate having an alkoxyalkyl group bonded as the alcohol-derived portion of the ester structure of (meth) acrylate. .

  The alkoxyalkyl (meth) acrylate is preferably an alkoxyalkyl (meth) acrylate having an alkoxy group having 1 to 12 carbon atoms and an alkylene group bonded to the alkoxy group having 1 to 18 carbon atoms. More preferably, the alkoxy group has 1 to 4 carbon atoms and the alkylene group bonded to the alkoxy group has 1 to 8 carbon atoms, and the alkoxy group has 1 to 2 carbon atoms. More preferred are alkoxyalkyl (meth) acrylates in which the alkylene group bonded to the alkoxy group has 1 to 4 carbon atoms.

  Examples of such alkoxyalkyl (meth) acrylates include 2-methoxymethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxymethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, Examples include 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate, and the like. Among these, 2-methoxyethyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate are particularly preferable.

  Since the alkoxy group has high hydrophilicity, it is considered to be excellent in retention and release of water vapor. In order to obtain sufficient moisture permeability, the alkoxyalkyl (meth) acrylate is preferably 50 to 80% by weight, more preferably 50 to 75% by weight, and more preferably 55 to 75% by weight, based on the total monomers constituting the copolymer. Further preferred. If it is 50% by weight or more, sufficient moisture permeability is obtained, and if it is 80% by weight or less, sufficient adhesiveness to the skin is expressed.

  (A-1) Monomer has high hydrophobicity, and since (a-4) monomer described later has high hydrophilicity, they are not excellent in compatibility with each other, only (a-1) monomer and (a-4) monomer. Copolymers made of are easily phase-separated and may cause a decrease in adhesiveness and storage stability. By using the monomer (a-3) as a monomer constituting the copolymer, the compatibility between the monomer (a-1) and the monomer (a-4) is improved, and the tackiness and storage stability are improved. Conceivable.

  <(A-4) Alkoxypolyalkylene glycol mono (meth) acrylate or alkoxypolyalkylene glycol allyl ether>

Alkoxypolyalkylene glycol mono (meth) acrylate is a compound represented by the following formula (1).

_{CH 2 = CR1-CO- (OZ} ) n-O-R2 Formula (1)

(In formula (1), Z represents an alkylene group, R1 represents hydrogen or a methyl group, R2 represents an alkyl group, and n represents an integer of 2 or more.)
In formula (1), Z is preferably an alkylene group having 2 to 3 carbon atoms, R2 is an alkyl group having 1 to 2 carbon atoms, and n is an integer of 2 to 20.

  Examples of the alkoxypolyalkylene glycol mono (meth) acrylate include MPE400A, MPE550A (manufactured by Osaka Organic Chemical Industry Co., Ltd.), Light Ester BC, 130MA, 041MA, Light Acrylate EC-A, MTG-A, EHDG-AT, 130A, DPM-A (above, manufactured by Kyoeisha Chemical Co., Ltd.), FANCYL FA-400M (100, manufactured by Hitachi Chemical Co., Ltd.), NK Ester AM-90, AM-130G, M-90G, M-230G (above, Shin-Nakamura Chemical Co., Ltd.), Bremer AME-400, PME-100, PME-200, PME-400, PME-1000 (above, manufactured by NOF Corporation) and the like.

Alkoxypolyalkylene glycol allyl ether is a compound represented by the following formula (2).

_{CH 2 = CR3-CH 2 -O-} (YO) m-R4 formula (2)

(In Formula (2), Y represents an alkylene group, R3 represents hydrogen or a methyl group, R4 represents an alkyl group, and m represents an integer of 1 or more.)
In the formula (2), Y is an alkylene group having 2 to 4 carbon atoms, R4 is an alkyl group having 1 to 4 carbon atoms, m is preferably an integer of 1 to 30, Y is an alkylene group having 2 to 3 carbon atoms, R4 Is more preferably an alkyl group having 1 to 2 carbon atoms, and m is preferably an integer of 1 to 20.

  Examples of the alkoxypolyalkylene glycol allyl ether include UNIOX PKA-5006, PKA-5209, UNISafe PKA-5015 (above, NOF Corporation) and the like.

  The alkoxy polyalkylene glycol mono (meth) acrylate or alkoxy polyalkylene glycol allyl ether is preferably 0.1 to 25% by weight, more preferably 1 to 25% by weight, based on all monomers constituting the copolymer, and 1 to 20%. More preferred is weight percent. By including an alkylene glycol moiety, it is considered that excellent performance in retention and release of water vapor is exhibited. Among the above, alkoxy polyalkylene glycol mono (meth) acrylate is preferable.

The monomer (a-3) and the monomer (a-4) are components that contribute to moisture permeability. The total content of the monomer (a-3) and the monomer (a-4) in all monomers constituting the copolymer is preferably 50 to 80% by weight. If it is 50% by weight or more, sufficient moisture permeability can be obtained, and if it is 80% by weight or less, durability to adhere to the skin can be secured. (A-4) As one aspect in the case of containing a monomer, (a-1) 5- (45% by weight) of an alkyl (meth) acrylate and (a-2) a hydroxyl group in all monomers constituting the copolymer (meta) ) 0.01 to 10% by weight of allyl ether having acrylate or hydroxyl group, (a-3) 50 to 78% by weight of alkoxyalkyl (meth) acrylate, (a-4) alkoxypolyalkylene glycol mono (meth) acrylate or alkoxypoly Mention may be made of a pressure-sensitive adhesive comprising a copolymer containing 1 to 25% by weight of alkylene glycol allyl ether.

  The copolymer (A) may contain other monomers other than the above monomers as monomers constituting the copolymer.

Other monomers include alicyclic monomers such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; aromatic monomers such as benzyl (meth) acrylate and phenoxyethyl (meth) acrylate; dimethylaminoethyl (meth) acrylate Amino group-containing monomers such as diethylaminoethyl (meth) acrylate; cyano group-containing monomers such as cyano (meth) acrylate; maleimide group-containing monomers such as maleimide and methylmaleimide; nitrile group-containing monomers such as (meth) acrylonitrile; glycidyl ( Examples thereof include epoxy group-containing monomers such as (meth) acrylate; vinyl esters such as vinyl acetate.
The content of other monomers can be copolymerized in the range of 0 to 20% by weight, preferably 0 to 15% by weight, particularly preferably 0 to 10% by weight, based on the total monomers constituting the copolymer.

  The copolymer (A) may contain a monomer having an acidic group as another monomer. When the monomer having an acidic group is used, there is an advantage that the adhesive strength can be increased and the adhesion durability can be improved. On the other hand, there is a tendency to cause strong pain and exfoliation when the tape is peeled off. The pressure-sensitive adhesive of the present invention preferably contains no monomer having an acidic group.

  Here, the acidic group means an acidic group such as a carboxyl group, a sulfo group, a phospho group (phosphoric acid group), and the monomer having an acidic group includes (meth) acrylic acid, maleic acid, itaconic acid, phosphonic group. A monomer having an acid group, a monomer having a sulfo group, and the like can be given.

  It is preferable that a copolymer (A) contains the monomer unit which has an amide bond as a monomer which comprises a copolymer.

  Examples of monomers having an amide bond include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-hexyl (meth) acrylamide, and N-vinyl. Pyrrolidone, acryloyl morpholine, vinyl caprolactam and the like can be mentioned.

  When using the monomer which has an amide bond, it is 0.05 to 5 weight% in all the monomers which comprise a copolymer (A), Preferably it is 0.1 to 4 weight%, More preferably, it is 0.1 to 0.1 weight%. 3% by weight. The monomer having an amide bond acts as a reaction catalyst between a hydroxyl group in the copolymer and an isocyanate compound as a curing agent described later, and contributes to stabilization of the reaction.

  The copolymer (A) has a weight average molecular weight of preferably 400,000 or more and less than 2 million, more preferably 600,000 or more and less than 1.8 million, and still more preferably 800,000 or more and less than 1.6 million. If it is 400,000 or more, it will be difficult to remain on the skin, and if it is less than 2 million, the skin sticking property will be good.

 The copolymer (A) preferably has a glass transition temperature (Tg) determined by the Fox formula of -70 ° C to 0 ° C. By using a (meth) acrylic copolymer having such a glass transition temperature, it is possible to obtain a pressure-sensitive adhesive having excellent skin adhesion durability and suppressing peeling pain.

 The copolymer can be produced by a known method, but is preferably produced by solution polymerization. In the solution polymerization, it is preferable to use methyl acetate, ethyl acetate, methyl ethyl ketone, toluene, acetone or the like as a solvent.

 Specifically, the solvent and the raw material monomer are charged into the reaction vessel in the proportions described above, a polymerization initiator is added under an inert gas atmosphere such as nitrogen gas, and the reaction temperature is increased to about 50 to 90 ° C. The polymerization reaction is carried out in -20 hours.

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

 Under the above conditions, the weight average molecular weight of the copolymer obtained is adjusted according to known techniques, such as the type and amount of the solvent used, the type and amount of the polymerization initiator, the reaction time, and the reaction temperature. Can be adjusted.

<Plasticizer (B)>
As the plasticizer (B), it is preferable to select at least one from a fatty acid ester, an epoxidized oil ester, a polyalkylene glycol ester, a phosphate ester and a citrate ester, and two or more types can be used in combination. Examples of fatty acid esters include monobasic acid systems such as isopropyl myristate, methyl laurate, and methyl oleate, and polybasic acid systems such as diisodecyl adipate and dilauryl azelate. Branched, saturated and unsaturated, aliphatic and aromatic can be multiplied. Examples of the epoxidized oil ester include epoxidized soybean oil ester, epoxidized linseed oil ester, epoxidized fatty acid octyl ester, etc., and having an epoxy moiety has an effect of forming a bond with a cured coating film. Cheap. Examples of the polyalkylene glycol ester include polyethylene glycol bis (2-ethylhexyl) ester, polypropylene glycol bislauryl ester, and the like. A structure in which ethylene and propylene are used in combination is also applicable to the alkylene glycol moiety. Examples of phosphate esters include phosphoric acids such as triethyl phosphate, triphenyl phosphate, tris (2-ethylhexyl) phosphate, and phosphorous acid such as triethyl phosphite, tris (tridecyl) phosphite, diphenyl monodecyl phosphite System. Examples of citric acid esters include acetyl triethyl citrate, acetyl tributyl citrate, acetyl tributyl citrate (2-ethylhexyl), etc., and the copolymer is obtained by capping the hydroxyl group of citric acid with acetyl or the like. Reaction inhibition between (A) and the curing agent (B) can be made difficult to occur.
The blending ratio of the plasticizer (B) is preferably 1 to 50 parts by weight, more preferably 1 to 40 parts by weight, and further preferably 5 to 40 parts by weight. When the blending ratio is 1 part by weight or more, the exfoliation resistance can be improved, and when it is 50 parts by weight or less, the minimum cohesive force can be maintained as the adhesive layer.

<Curing agent>
As a curing agent for curing the copolymer, a compound having an isocyanato group (hereinafter referred to as an isocyanate curing agent) is preferably used. Examples of isocyanate curing agents include two or more isocyanate groups in the molecule such as tolylene diisocyanate, xylylene diisocyanate, chlorophenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate. Compounds having: compounds obtained by addition reaction with polyhydric alcohols such as trimethylolpropane and pentaerythritol, their isocyanurate compounds and burette type compounds, as well as known polyether polyols, polyester polyols, acrylic polyols, polybutadienes Two or more ions are added in the urethane prepolymer type molecule that has undergone addition reaction with polyol, polyisoprene, etc. It can be exemplified compounds having a cyanate group.

The kind of the curing agent can be appropriately selected according to the base material, application and the like. Tolylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate: compounds obtained by addition reaction with polyhydric alcohols such as trimethylolpropane and pentaerythritol, their isocyanurate compounds and burette type compounds can be preferably used.
The blending ratio of the curing agent depends on the amount of the functional group contained in the copolymer, but is preferably 0.01 to 5 parts by weight, and 0.1 to 3 parts by weight with respect to 100 parts by weight of the copolymer. More preferred is 0.1 to 2 parts by weight.

  Various additives can be added to the pressure-sensitive adhesive of the present invention as desired. For example, antibacterial agents, humectants, vitamins, fragrances and the like can be mentioned. These are compounded in effective amounts as necessary.

<Adhesive tape>
The pressure-sensitive adhesive tape produced using the pressure-sensitive adhesive of the present invention may be sterilized by an autoclave, ethylene oxide gas, radiation, or the like. In order to prevent deterioration of the adhesive due to radiation sterilization, known additives can be used. Electron and ion scavengers that inactivate electrons and ions generated in the initial irradiation process such as pyrene and quinone, energy transfer agents that inactivate excited species such as acenaphthene, mercaptans, octahydrophenanthrenes, monoalkyldiphenyl ethers, etc. Radical scavengers that inactivate polymer radicals, phenolic anti-aging agents, organic thioates, phosphoric acid triesters, polymer radicals such as BHT, antioxidants that inactivate peroxy radicals, phthalates And plasticizers that inactivate polymer radicals such as epoxy plasticizers and chlorinated paraffins.

  In order to produce an adhesive tape for skin application using the adhesive of the present invention, an adhesive is applied to one side of a substrate. The base material is not particularly limited, but main examples include rayon, cotton, polyester yarn and other woven fabrics, olefin-based nonwoven fabrics, knitted fabrics, and plasticized soft polychlorinated products. Vinyl, unplasticized soft polyvinyl chloride, polyethylene, polypropylene, polybutene, ethylene-methyl methacrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-propylene rubber, polyamide, polyethylene terephthalate, polyurethane, polyvinylidene chloride, polyvinyl alcohol A film or sheet made of a synthetic resin such as In addition, a flexible film or sheet such as a plastic foam sheet, cellulose, or cellulose acetate can be used. These substrates may be subjected to corona discharge treatment or the like as necessary. When the base material excellent in moisture permeability is used, the moisture permeability excellent in the pressure-sensitive adhesive of the present invention can be sufficiently exhibited.

  The pressure-sensitive adhesive of the present invention may be diluted with a solvent so that it can be easily applied. As the solvent, known solvents can be used, and examples thereof include ethyl acetate, acetone, methyl ethyl ketone, and toluene. The pressure-sensitive adhesive solution is mixed with a curing agent and an additive, and this is applied to one side of the substrate and dried. When a high temperature is required for the crosslinking reaction, heating is performed during or after drying. Further, it is also possible to employ a method in which the pressure-sensitive adhesive composition is applied to a release liner such as a release paper and then superimposed on the substrate. Providing perforations in the adhesive tape can improve air permeability.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following examples, “parts” and “%” represent “parts by mass” and “mass%”, respectively, unless otherwise specified. Moreover, the symbol of the material used in the following examples is shown.

<(A-1) Alkyl (meth) acrylate>
<Alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms>
BA: n-butyl acrylate 2EHA: 2-ethylhexyl acrylate IOA: isooctyl acrylate <alkyl (meth) acrylate having an alkyl group having 9 to 22 carbon atoms>
INA: isononyl acrylate IDMA: isodecyl methacrylate LA: lauryl acrylate LMA: lauryl methacrylate ISA: isostearyl acrylate

<(A-2) (Meth) acrylate having hydroxyl group or allyl ether having hydroxyl group>
2HEA: 2-hydroxyethyl acrylate 4HBA: 4-hydroxybutyl acrylate 55PET-800: Bremer 55PET-800, polyethylene glycol-tetramethylene glycol-monomethacrylate (random type), NOF PKA-5001: UNIOX PKA-5001 , Polyethylene glycol-allyl ether, manufactured by NOF Corporation

<(A-3) Alkoxyalkyl (meth) acrylate>
MEA: methoxyethyl acrylate MEMA: methoxyethyl methacrylate EEA: ethoxyethyl acrylate

<(A-4) Alkoxypolyalkylene glycol mono (meth) acrylate or alkoxypolyalkylene glycol allyl ether>
EC-A: Light acrylate EC-A, ethoxy-diethylene glycol acrylate, Kyoeisha Chemical Co., Ltd. MTG-A: Light acrylate MTG-A, methoxy-triethylene glycol acrylate, Kyoeisha Chemical Co., Ltd. DPM-A: Light acrylate DPM-A , Methoxydipropylene glycol acrylate, Kyoeisha Chemical Co., Ltd. M-90G: NK ester M-90G, methoxypolyethylene glycol methacrylate, Shin-Nakamura Chemical Co., Ltd. AM-90G: NK ester AM-90G, methoxypolyethylene glycol acrylate, Shin-Nakamura MPE400A manufactured by Chemical Industry Co., Ltd .: Methoxypolyethylene glycol acrylate, BC manufactured by Osaka Organic Chemical Industry Co., Ltd .: Light ester BC, Butoxydiethylene glycol methacrylate, 04 manufactured by Kyoeisha Chemical Co., Ltd. MA: light ester 041MA, methoxypolyethylene glycol methacrylate, PKA-5008 manufactured by Kyoeisha Chemical Co., Ltd .: UNIOX PKA-5008, methoxy-polyethylene glycol-allyl ether, PKA-5015 manufactured by NOF Corporation: unisafe PKA-5015, butoxy-polyethylene glycol -Polypropylene glycol-allyl ether, manufactured by NOF Corporation

<Other monomers>
AA: acrylic acid AM: acrylamide NVP: N-vinylpyrrolidone ACMO: acryloylmorpholine

<Curing agent>
HT: Sumidur HT, hexamethylene diisocyanate-trimethylolpropane, N3200 manufactured by Sumika Covestrourethane, Desmodur N3200, hexamethylene diisocyanate-burette, N3300 manufactured by Sumika Covestrourethane, Desmodur N3300, hexamethylene Diisocyanate-nurate, Sumika Covestrourethane L: Coronate L, Tolylene diisocyanate-trimethylolpropane, Tosoh 2030: Coronate 2030, Tolylene diisocyanate-nurate, Tosoh D-110N: Takenate D -110N, xylylene diisocyanate-trimethylolpropane, Mitsui Chemicals EX-212: Denacol EX-212, 1,6-hexanediol diglycidyl acetate Le, Nagase Chemtex Co., Ltd.

<Plasticizer (B)>
IPM-R: Unistar IPM-R, isopropyl myristate, NOF W121: Eposizer W121, epoxidized soybean oil ester, DIC W262: monosizer W262, polyalkylene glycol ester, DIC TOP: TOP, Tris (2-Ethylhexyl) phosphate, Daihachi Chemical Industry BII: CITROFOL BII, acetyltributyl citrate, Jungbunzurawa

Example 1
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 7.5 parts of n-butyl acrylate, 17 parts of lauryl acrylate, 0.5 parts of 2-hydroxyethyl acrylate, methoxyethyl 25 parts of acrylate, 69 parts of ethyl acetate and 0.01 part of azobisisobutyronitrile were charged into a 4-neck flask, and the temperature was raised to 80 ° C. while introducing nitrogen gas. In a dropping funnel, 7.5 parts of n-butyl acrylate, 17 parts of lauryl acrylate, 0.5 part of 2-hydroxyethyl acrylate, 25 parts of methoxyethyl acrylate and 69 parts of ethyl acetate, azobisisobutyronitrile as a polymerization initiator 01 parts were charged and dropped, and a polymerization reaction was carried out at 80 ° C. for 7 hours in a nitrogen atmosphere. After completion of the reaction, 48 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 1,000,000.

<Weight average molecular weight (Mw)>
Mw was measured under the following conditions. Mw was determined by a calibration curve method using polystyrene having a known weight average molecular weight as a standard substance.
Device name: LC-GPC system “Prominence” manufactured by Shimadzu Corporation
Column: Two TSKgel α-M manufactured by Tosoh Corporation are connected in series. Mobile phase solvent: Dimethylformamide Flow rate: 1.0 ml / min Column temperature: 40 ° C

<Creation of coating liquid>
Add 100 parts of Sumijoule HT as a curing agent in terms of non-volatile content and 1 part of isopropyl myristate as a plasticizer in terms of non-volatile content to 100 parts of the non-volatile content of the resulting acrylic adhesive, and stir. A coating solution was obtained.

<Creation of adhesive tape>
An adhesive tape was produced according to the method as described below, and the characteristics were evaluated.
(1) Preparation of moisture vapor permeability evaluation pressure-sensitive adhesive tape The above coating solution was applied on a polyester separator having a thickness of 38 μm so that the thickness after drying was 25 μm, and dried in a hot air oven at 100 ° C. for 2 minutes. did. After drying, it was laminated on a 38 μm thick moisture permeable urethane sheet (moisture permeability 3,500 g / m ² · 24 h), and further cured at 50 ° C. for 3 days to obtain an adhesive tape.
(2) Preparation of pressure-sensitive adhesive tape for evaluation of exfoliation resistance and adhesion to base material Polyester separator with a thickness of 38 μm [trade name “Super Stick” SP-PET38, manufactured by Lintec Corporation, the same applies hereinafter. On top, the coating solution obtained above was applied so that the thickness after drying was 25 μm, and dried in a hot air oven at 100 ° C. for 2 minutes. After drying, it was laminated on a corona-treated polypropylene film [trade name “Trephan VL12”] and further cured at 50 ° C. for 3 days to obtain an adhesive tape.

<Moisture permeability>
The test based on JISL1099 was done. In a cylindrical weighing container with a diameter of 70 mm, 42 g of pure water at 40 ° C. was put, and the adhesive tape was fixed as a lid of the weighing container so that the adhesive coating surface of the adhesive tape was down, and the container was sealed. . This was left in a constant temperature and humidity chamber at 40 ° C. and a relative humidity of 50% RH for 1 hour. From the weight loss of the weighing container, the permeated water amount per 1 square meter and 24 hours was calculated. (Unit: g / m ² · 24 h).
○: 2000 g / m ² · 24 h or more (good)
Δ: 1000 g / m ² · 24 h or more, less than 2000 g / m ² · 24 h (usable)
×: Less than 1000 g / m ² · 24 h (defect)

<Stratum corneum resistance>
The pressure-sensitive adhesive tape was cut into a size of 20 mm wide and 80 mm long to prepare a measurement sample. Next, in an environment of 23 ° C. and 50% RH, the polyester separator was peeled off from the sample, and the degree of horny peeling when the exposed adhesive layer was peeled off after 24 hours had been applied to the front arm of the subject's forearm was determined according to the following criteria: Visual evaluation with a loupe.
○: Exfoliation of keratin is almost completely absent (good)
Δ: Exfoliation of keratin is observed at a ratio of about 30% or less (usable)
X: Exfoliation of keratin is observed at a rate exceeding about 30% (defect)

<Base material adhesion>
The degree of transfer of the adhesive layer remaining on the skin of the subject after the keratin peel resistance test was evaluated according to the following criteria.
○: No transfer of the adhesive layer is observed (good)
Δ: Transfer of the adhesive layer is observed at a ratio of about 30% or less (can be used)
X: Transfer of the adhesive layer is observed at a rate exceeding about 30% (defect)

(Examples 2-11, 13-25)
A pressure-sensitive adhesive and a pressure-sensitive adhesive tape were produced, measured and evaluated in the same manner as in Example 1, except that the materials, compositions, and amounts shown in Table 1 were changed. In addition, unless otherwise indicated, the numerical value in Table 1 represents a part, and the blank represents that it is not using.

(Example 12)
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 10 parts of 2-ethylhexyl acrylate, 7 parts of lauryl methacrylate, 0.5 part of 2-hydroxyethyl acrylate, 32 parts of methoxyethyl acrylate Part, 0.5 part of ethoxydiethylene glycol acrylate (Light acrylate EC-A: manufactured by Kyoeisha Chemical Co., Ltd.), 25 parts of ethyl acetate, 50 parts of methyl ethyl ketone, 0.2 part of azobisisobutyronitrile were introduced, and nitrogen gas was introduced. The temperature was raised to 80 ° C. In a dropping funnel, 10 parts of 2-ethylhexyl acrylate, 7 parts of lauryl methacrylate, 0.5 part of 2-hydroxyethyl acrylate, 32 parts of methoxyethyl acrylate, 0.5 part of ethoxydiethylene glycol acrylate (Light acrylate EC-A: manufactured by Kyoeisha Chemical Co., Ltd.) Then, 75 parts of ethyl acetate and 0.2 part of azobisisobutyronitrile as an initiator were added dropwise, and a polymerization reaction was performed at 80 ° C. for 7 hours in a nitrogen atmosphere. After completion of the reaction, 36 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 400,000.
Furthermore, except having changed into the kind of hardening | curing agent shown in Table 1, the adhesive and the adhesive tape were manufactured similarly to Example 1, and it measured and evaluated.

(Comparative Example 1)
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 41.5 parts of 2-ethylhexyl acrylate, 5 parts of isostearyl acrylate, 2.5 parts of 2-hydroxyethyl acrylate, N -1.0 part of vinylpyrrolidone, 50 parts of ethyl acetate as a polymerization solvent and 0.02 part of azobisisobutyronitrile were charged, and the temperature was raised to 80 ° C while introducing nitrogen gas. In a dropping funnel, 41.5 parts of 2-ethylhexyl acrylate, 5 parts of isostearyl acrylate, 2.5 parts of 2-hydroxyethyl acrylate, 1.0 part of N-vinylpyrrolidone and 50 parts of ethyl acetate, azobisisobutyro as an initiator 0.2 parts of nitrile was charged and dropped, and a polymerization reaction was carried out at 80 ° C. for 7 hours in a nitrogen atmosphere. After completion of the reaction, 86 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 700,000.
Furthermore, except having changed into the kind of hardening | curing agent shown in Table 1, the adhesive and the adhesive tape were manufactured similarly to Example 1, and it measured and evaluated.

<Creation of coating liquid>
To 100 parts of the nonvolatile content of the obtained acrylic pressure-sensitive adhesive, 1.0 part by weight of Coronate L as a curing agent is added in an amount of 1.0 part by weight, and 10 parts of isopropyl myristate is added as a plasticizer in terms of a nonvolatile content, and stirred. A coating solution was obtained. An adhesive tape was obtained in the same manner as in Example 1.

(Comparative Example 2)
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 18.5 parts isooctyl acrylate, methoxypolyethylene glycol acrylate (NK ester AM-90G: manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 30 parts, 1.5 parts of acryloylmorpholine, 30 parts of ethyl acetate as a polymerization solvent, 20 parts of methyl ethyl ketone, 0.1 part of azobisisobutyronitrile, and heated to 80 ° C. while introducing nitrogen gas did. 18.5 parts of isooctyl acrylate, 30 parts of methoxypolyethylene glycol acrylate (NK ester AM-90G: manufactured by Shin-Nakamura Chemical Co., Ltd.), 1.5 parts of acryloylmorpholine and 50 parts of ethyl acetate, azobis as an initiator 0.1 part of isobutyronitrile was added and dropped, and a polymerization reaction was carried out at 80 ° C. for 7 hours in a nitrogen atmosphere. After completion of the reaction, 86 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 600,000.

<Creation of coating liquid>
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 without adding a curing agent to the obtained acrylic pressure-sensitive adhesive.

(Comparative Example 3)
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, isononyl acrylate 32.5 parts, methoxyethyl acrylate 15 parts, acrylic acid 2.5 parts, ethyl acetate as a polymerization solvent And 0.2 part of azobisisobutyronitrile were charged, and the temperature was raised while introducing nitrogen gas. A dropping funnel was charged with 32.5 parts of isononyl acrylate, 15 parts of methoxyethyl acrylate, 2.5 parts of acrylic acid and 50 parts of ethyl acetate, and 0.2 parts of azobisisobutyronitrile as an initiator. The polymerization reaction was carried out at 80 ° C. for 7 hours. After completion of the reaction, 86 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 800,000.

<Creation of coating liquid>
0.1 parts by weight of Sumijoule HT in terms of nonvolatile content was added to 100 parts of nonvolatile content of the obtained acrylic pressure-sensitive adhesive and stirred to obtain a coating solution. An adhesive tape was obtained in the same manner as in Example 1.

(Comparative Example 4)
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 40 parts of 2-ethylhexyl acrylate, 2.5 parts of hydroxybutyl acrylate, ethoxydiethylene glycol acrylate (Light acrylate EC-A: Kyoeisha) Chemical Co., Ltd.) 7.5 parts, 50 parts of ethyl acetate as a polymerization solvent and 0.02 part of azobisisobutyronitrile were charged, and the temperature was raised to 80 ° C. while introducing nitrogen gas. In a dropping funnel, 40 parts of 2-ethylhexyl acrylate, 2.5 parts of hydroxybutyl acrylate, 7.5 parts of ethoxydiethylene glycol acrylate (Light acrylate EC-A: manufactured by Kyoeisha Chemical Co., Ltd.), 50 parts of ethyl acetate, azobisiso as an initiator 0.02 part of butyronitrile was charged and dropped, and a polymerization reaction was carried out at 80 ° C. for 7 hours in a nitrogen atmosphere. After completion of the reaction, 86 parts of ethyl acetate was added for dilution to obtain an adhesive having a nonvolatile content of 35% and a weight average molecular weight of 1,000,000.

<Creation of coating liquid>
To 100 parts of the nonvolatile content of the obtained acrylic pressure-sensitive adhesive, 0.3 part by weight of Sumijoule HT as a curing agent was added in terms of nonvolatile content and stirred to obtain a coating liquid. An adhesive tape was obtained in the same manner as in Example 1.

Claims (12)

A pressure-sensitive adhesive comprising at least a copolymer (A) containing a structural unit derived from a monomer represented by the following (a-1), (a-2) and (a-3) and a plasticizer (B): The pressure-sensitive adhesive contains 1 to 50 parts by weight of the plasticizer (B) with respect to 100 parts by weight of the copolymer (A), and the copolymer (A) is contained in all monomers constituting the copolymer (A). A pressure-sensitive adhesive comprising the following content.
(A-1) Alkyl (meth) acrylate 5 to 49% by weight
(A-2) (Meth) acrylate having a hydroxyl group or allyl ether having a hydroxyl group 0.01 to 10% by weight
(A-3) Alkoxyalkyl (meth) acrylate 50-80% by weight   (A-1) Alkyl (meth) acrylate having 15 to 44% by weight of alkyl (meth) acrylate having 4 to 8 carbon atoms and 9 to 9 carbon atoms in all monomers constituting the copolymer (A). The pressure-sensitive adhesive according to claim 1, comprising 5 to 34% by weight of an alkyl (meth) acrylate having 22 alkyl groups.   The pressure-sensitive adhesive according to claim 1 or 2, wherein the copolymer (A) is a copolymer (A) containing no structural unit derived from a monomer having an acidic group.   The pressure-sensitive adhesive according to any one of claims 1 to 3, wherein the copolymer (A) further comprises a structural unit derived from a monomer having an amide bond.   The copolymer (A) further comprises 0.1 to 25% by weight of a structural unit derived from (a-4) alkoxy polyalkylene glycol mono (meth) acrylate or alkoxy polyalkylene glycol allyl ether. The adhesive as described.   The pressure-sensitive adhesive according to any one of claims 1 to 5, wherein the copolymer (A) has a weight average molecular weight of 400,000 or more and less than 2 million.   The pressure-sensitive adhesive according to any one of claims 1 to 6, wherein the plasticizer (B) is at least one selected from the group consisting of fatty acid esters, epoxidized oil esters, polyalkylene glycol esters, phosphate esters and citrate esters.   Furthermore, the adhesive in any one of Claims 1-7 containing a hardening | curing agent.   The pressure-sensitive adhesive according to any one of claims 1 to 8, which is used for medical purposes. A method for producing a pressure-sensitive adhesive in which at least the monomers represented by the following (a-1), (a-2) and (a-3) are copolymerized and then mixed with a plasticizer (B): A method for producing a pressure-sensitive adhesive, which comprises copolymerizing all the monomers constituting A) at the following content.
(A-1) Alkyl (meth) acrylate 5 to 49% by weight
(A-2) (Meth) acrylate having a hydroxyl group or allyl ether having a hydroxyl group 0.01 to 10% by weight
(A-3) Alkoxyalkyl (meth) acrylate 50-80% by weight   A pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive according to claim 1.   The manufacturing method of the adhesive tape which coats the adhesive in any one of Claims 1-9 to a base material.