JP2001123145A - Urethane resin adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a urethane resin adhesive improved in a disadvantage which is a lack of weatherability in conventional urethane resin adhesives. SOLUTION: This urethane resin adhesive comprises a urethane resin (B) and an antidegradation agent (d) and the urethane resin (B) is a urethane prepolymer (A) obtained by reacting a polyol (a) with a polyisocyanate (b) in the presence of a catalyst (c).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a urethane resin pressure-sensitive adhesive used for pressure-sensitive adhesive tapes, labels, seals, decorative sheets, non-slip sheets, double-sided pressure-sensitive adhesive tapes and the like.

[0002]

2. Description of the Related Art Conventionally, urethane resin pressure-sensitive adhesives have many products which utilize the characteristics of high cohesion and adhesion, and the removability with time is good under relatively mild conditions. Under severe conditions such as direct sunlight and ultraviolet rays, there were problems such as an increase in adhesive strength and "adhesive residue" in which the adhesive was transferred to an adherend, resulting in poor weather resistance.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a urethane resin pressure-sensitive adhesive which can improve the disadvantage of poor weather resistance of the urethane resin pressure-sensitive adhesive.

[0004]

As a result of various studies on the resin composition and reaction method of the urethane resin, a deterioration inhibitor (d) was added to prevent the decomposition of a polyol which is one of the urethane constituents. By doing so, it has been found that a urethane resin pressure sensitive adhesive having good weather resistance can be obtained.

That is, the present invention relates to a urethane resin (B)
A urethane resin pressure-sensitive adhesive containing a polyurethane (A) and a polyisocyanate (b) in the presence of a catalyst (c). It relates to a urethane resin pressure-sensitive adhesive which is a prepolymer (A).

Further, the present invention provides a urethane resin pressure-sensitive adhesive containing a urethane resin (C) and a deterioration inhibitor (d),
A urethane resin (C) reacts a polyol (a) with a polyisocyanate (b) in the presence of a catalyst (c) to form a urethane prepolymer (A) with a polyamine (e) and an unsaturated double bond. The present invention relates to a urethane resin pressure-sensitive adhesive characterized in that a chain is extended with a compound (g) obtained by subjecting a compound (f) having the compound to a Michael addition reaction.

The present invention also relates to a urethane resin pressure-sensitive adhesive containing a urethane resin (C ") and a deterioration inhibitor (d), wherein the urethane resin (C") comprises a polyol (a) and a polyisocyanate (b). ) Is reacted in the presence of a catalyst (c) with a compound (g) obtained by subjecting a polyamine (e) and a compound (f) having an unsaturated double bond to a Michael addition reaction with a polyamine (e). A urethane resin (C ') having an isocyanato group at the end obtained by chain extension, and a compound (h) having an active hydrogen capable of reacting with the isocyanato group, and a urethane resin pressure-sensitive adhesive. .

The present invention also relates to the urethane resin pressure-sensitive adhesive, wherein the deterioration inhibitor (d) contains an antioxidant (i).

The present invention also relates to the urethane resin pressure-sensitive adhesive, wherein the deterioration inhibitor (d) contains an antioxidant (i) and an ultraviolet absorber (j) or a light stabilizer (k).

[0010] The present invention also relates to the urethane resin pressure-sensitive adhesive, wherein the deterioration inhibitor (d) contains an antioxidant (i), an ultraviolet absorber (j) and a light stabilizer (k).

The present invention also provides a first step of reacting a polyol (a) with a polyisocyanate (b) in the presence of a catalyst (c) to synthesize a urethane prepolymer (A),
The urethane prepolymer (A) is converted to a polyamine (e)
A second step of synthesizing a urethane resin (C ′) having an isocyanato group at a terminal by extending the chain with a compound (g) obtained by subjecting a compound (f) having an unsaturated double bond to a compound (f) having an unsaturated double bond, A urethane resin (C ′) having an isocyanato group and a compound (h) having an active hydrogen capable of reacting with the isocyanato group
And a fourth step of blending the urethane resin (C ″) with a deterioration inhibitor (d).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Deterioration inhibitor (d) used in the present invention
At least one selected from the group consisting of an antioxidant (i), an ultraviolet absorber (j) and a light stabilizer (k)
Use seeds.

The antioxidant (i) used in the present invention includes a radical chain inhibitor (primary antioxidant) and a peroxide decomposer (secondary antioxidant).

The radical chain inhibitor (primary antioxidant) includes a phenolic antioxidant and an amine antioxidant.

Examples of the peroxide decomposing agent (secondary antioxidant) include sulfur-based antioxidants and phosphorus-based antioxidants.

Examples of the phenolic antioxidants include monophenolic, bisphenolic and high-molecular phenolic antioxidants.

The monophenolic antioxidants include:
2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearin-β- (3,5-di-t-
Butyl-4-hydroxyphenyl) propionate, and the like.

As the bisphenol-based antioxidant,
2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-
6-t-butylphenol), 4,4′-thiobis (3
-Methyl-6-t-butylphenol), 4,4′-butylidenebis (3-methyl-6-t-butylphenol), 3,9-bis [1,1-dimethyl-2- [β-
(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-
And tetraoxaspiro [5,5] undecane.

Examples of the polymer type phenolic antioxidant include 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane and 1,3,5-trimethyl-2,4. , 6-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis-
[Methylene-3- (3 ', 5'-di-t-butyl-4'
-Hydroxyphenyl) propionate] methane, bis [3,3′-bis- (4′-hydroxy-3′-tert-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3 ′, 5 '-Di-t-butyl-4'-hydroxybenzyl) -S-triazine-2,
4,6- (1H, 3H, 5H) trione, tocophenol, and the like. IRGANOX L 135 (Ciba Specialty Chemicals Co., Ltd.) is particularly preferred because of its compatibility with resins.

Examples of the sulfur-based antioxidants include dilauryl 3,3'-thiodipropionate, dimyristyl 3,
3'-thiodipropionate, distearyl 3,3'-
Thiodipropionate, and the like.

Examples of the phosphorus-based antioxidants include triphenyl phosphite, diphenyl isodecyl phosphite, phenyl diisodecyl phosphite and the like.

The ultraviolet absorbent (j) used in the present invention includes benzophenone, benzotriazole, salicylic acid, oxalic anilide, cyanoacrylate, and the like.
And triazine-based ultraviolet absorbers.

As the benzophenone type ultraviolet absorber,
2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-
Octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2'-dihydroxy-
4-dimethoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane, And the like.

As the benzotriazole ultraviolet absorber, 2- (2'-hydroxy-5'-methylphenyl)
Benzotriazole, 2- (2'-hydroxy-5'-
tert-butylphenyl) benzotriazole, 2-
(2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) 5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl)
Benzotriazole, 2- (2'-hydroxy-4'-
Octoxyphenyl) benzotriazole, 2- [2 ′
-Hydroxy-3 ′-(3 ″, 4 ″, 5 ″,
6 ″,-tetrahydrophthalimidomethyl) -5′-
Methylphenyl] benzotriazole, 2,2 ′ methylenebis [4- (1,1,3,3-tetramethylbutyl)
-6- (2H-benzotriazol-2-yl) phenol], [2 (2'-hydroxy-5'-methacryloxyphenyl) -2H-benzotriazole, and the like. TUNUVIN 571 (Ciba Specialty Chemicals Co., Ltd.) is particularly preferred because of its compatibility with the resin.

Examples of the salicylic acid-based ultraviolet absorber include phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate and the like.

Examples of cyanoacrylate-based ultraviolet absorbers include 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate and ethyl-2-cyano-3,3'-.
And diphenyl acrylate.

The light stabilizer (k) used in the present invention includes:
Light stabilizers such as hindered amine light stabilizers and ultraviolet light stabilizers can be mentioned.

Examples of the hindered amine light stabilizer include:
[Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate], bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, methyl 1,2,2
2,6,6-pentamethyl-4-piperidyl sebacate can be mentioned. The brand name is TINUVI
N 765 (Ciba Specialty Chemicals Co., Ltd.), ADK STAB LA-77 (Asahi Denka), Chima
ssorb 944LD (Ciba Specialty Chemicals Co., Ltd.), TINUVIN 622LD (Ciba Specialty Chemicals Co., Ltd.), TINUV
IN 144 (Ciba Specialty Chemicals Co., Ltd.), ADK STAB LA-57 (Asahi Denka), ADK STAB LA-62 (Asahi Denka), ADK STAB LA-67
(Asahi Denka), ADK STAB LA-63 (Asahi Denka), ADK STAB LA-68 (Asahi Denka), ADK STAB LA-8
2 (Asahi Denka), ADK STAB LA-87 (Asahi Denka), G
oodrite UV-3034 (Goodrich)
Can be mentioned. TINUVIN 765 (Ciba Specialty Chemicals Co., Ltd.) is particularly preferred because of its compatibility with the resin.

As the ultraviolet stabilizer, nickel bis (octylphenyl) sulfide, [2,2'-thiobis (4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-
Di-tert-butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, benzoate-type quencher, nickel-
And dibutyldithiocarbamate.

Antioxidant (i) as deterioration inhibitor (d)
And an ultraviolet absorber (j) or a light stabilizer (k), and further preferably include all of an antioxidant (i), an ultraviolet absorber (j) and a light stabilizer (k). TINUVIN B 75 (Ciba Specialty Chemicals Co., Ltd.) is IRGANOX L13
5 (Ciba Specialty Chemicals Co., Ltd.) and T
Including INUVIN 571 (Ciba Specialty Chemicals Co., Ltd.) and TINUVIN 765 (Ciba Specialty Chemicals Co., Ltd.), it is preferable because they can be used without interfering with each other's effects. The amount used is preferably from 0 to 10% by weight of the solid content.

The urethane prepolymer (A) used in the present invention is obtained by a urethanization reaction between the polyol (a) and the polyisocyanate (b).

The polyol (a) used in the present invention includes polyester polyol, polyether polyol, polyester polyol and / or polyurethane polyol which is a reaction product of polyether polyol and diisocyanate, and polyether adduct of polyhydric alcohol. Used.

As the polyester polyol used in the present invention, known polyester polyols can be used. Terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid,
Trimellitic acid and the like, and glycol components such as ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexane glycol, 3-methyl-1,5-pentanediol,
3,3′-dimethylol heptane, polyoxyethylene glycol, polyoxypropylene glycol, 1,4
-Butanediol, neopentyl glycol, butylethylpentanediol, and glycerin, trimethylolpropane, pentaerythritol and the like as polyol components. In addition, polycaprolactone, poly (β
-Methyl-γ-valerolactone), and polyester polyols obtained by ring-opening polymerization of lactones such as polyvalerolactone. The molecular weight of the polyester polyol can be used from a low molecular weight to a high molecular weight, preferably a polyester polyol having a molecular weight of 1,000 to 5,000 and bifunctional or more, more preferably a molecular weight of 1,
A polyester polyol having a bifunctionality of 500 to 3,500 or more is used. The use amount thereof is preferably 0 to 50 mol% in the polyol constituting the urethane prepolymer (A).

As the polyether polyol used in the present invention, a known polyether polyol can be used. For example, water, propylene glycol, ethylene glycol, glycerin, using a low molecular weight polyol such as trimethylolpropane as an initiator, ethylene oxide, propylene oxide, butylene oxide, polyether polyol obtained by polymerizing an oxirane compound such as tetrahydrofuran Specifically, those having two or more functional groups, such as polypropylene glycol, polyethylene glycol, and polytetramethylene glycol, can be used. The molecular weight of the polyether polyol can be used from a low molecular weight to a high molecular weight, but is preferably a polyether polyol having a molecular weight of 1,000 to 5,000 and difunctional or higher, more preferably a molecular weight of 1,500 to 4,000. Is used. The use amount thereof is preferably 50 to 100 mol% in the polyol constituting the urethane prepolymer (A).

The polyurethane polyol which is a reaction product of the polyester polyol and / or polyether polyol and the polyisocyanate (b) used in the present invention includes a urethane reaction product of the polyester polyol and the polyisocyanate (b), and a polyether polyol and a polyisocyanate. The urethanization reaction product of isocyanate (b), polyester polyol and polyether polyol and urethanization reaction of polyisocyanate (b) are included.
In the polyurethane polyol of the present invention, both terminal components consist of polyester polyol or polyether polyol, and both terminals are hydroxyl groups. The polyester polyol and polyether polyol used here are the compounds described above. The polyisocyanate (b) is a polyisocyanate (b) described later. The molecular weight of the polyurethane polyol can be used from a low molecular weight to a high molecular weight, but is preferably 1,000 to 5,
A 2,000 bifunctional or more functional polyurethane polyol, more preferably, a 2,000 to 4,000 bifunctional or more functional polyurethane polyol is used.

The polyether adduct of polyhydric alcohol used in the present invention includes glycerin, sorbitol, trimethylolpropane, trimethylolbutane, 1,2,6-
It is obtained by adding a polyether polyol to a polyhydric alcohol such as hexanetriol or pentaerythritol. Adducts of partially esterified polyhydric alcohols and polyether polyols can also be used. In this case, the polyether moiety may be a block polymer or a random polymer. The terminal to which the polyether polyol is added is a hydroxyl group, but may be partially blocked with an alkyl group or an aromatic hydrocarbon group.

In the present invention, if necessary, some glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane and pentaerythritol, ethylenediamine, N- Polyvalent amines such as aminoethylethanolamine, isophoronediamine and xylylenediamine can also be used in combination.

The polyisocyanate (b) used in the present invention includes aromatic polyisocyanate, aliphatic polyisocyanate, araliphatic polyisocyanate, alicyclic polyisocyanate and the like.

As the aromatic polyisocyanate, 1, 1
3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate,
2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,
Examples thereof include 3,5-triisocyanatebenzene, dianisidine diisocyanate, 4,4'-diphenylether diisocyanate, and 4,4 ', 4 "-triphenylmethane triisocyanate.

Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-
Butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate and the like can be mentioned.

As the araliphatic polyisocyanate,
ω, ω′-diisocyanate-1,3-dimethylbenzene, ω, ω′-diisocyanate-1,4-dimethylbenzene, ω, ω′-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate And 1,3-tetramethylxylylene diisocyanate.

Examples of the alicyclic polyisocyanate include 3-
Isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-
2,6-cyclohexane diisocyanate, 4,4'-
Methylene bis (cyclohexyl isocyanate), 1,
4-bis (isocyanatomethyl) cyclohexane,
1,4-bis (isocyanatomethyl) cyclohexane and the like can be mentioned.

Further, a trimethylolpropane adduct of the above-mentioned polyisocyanate (b), a burette having reacted with water, a trimer having an isocyanurate ring, and the like can also be used in combination. A reaction product of the above-mentioned polyhydric alcohol polyether adduct and diisocyanate can also be used as the polyisocyanate (b).

As the polyisocyanate (b) used in the present invention, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate) and the like are preferable.

The compound (g) obtained by subjecting the polyamine (e) used in the present invention to a Michael addition reaction with the compound (f) having an unsaturated double bond includes a known polyamine (e) and an unsaturated double bond. An amine compound obtained by subjecting a compound (f) having the above to a Michael addition reaction can be used. When a polyamine compound obtained by subjecting a polyamine (e) and a compound (f) having an unsaturated double bond to a Michael addition reaction is used, the chain elongation becomes a mild reaction as compared with the case of using the polyamine (e) alone, and the control is carried out. Is particularly easy and preferred.

Known polyamines (e) used in the present invention include ethylenediamine, isophoronediamine, phenylenediamine, 2,2,4-trimethylhexamethylenediamine, tolylenediamine, hydrazine, piperazine, hexamethylenediamine, propylenediamine, and the like. Diamines such as dicyclohexylmethane-4,4-diamine, 2-hydroxyethylethylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine are exemplified. be able to. Isophorone diamine,
2,2,4-Trimethylhexamethylenediamine is preferable because the reaction can be easily controlled and the hygiene is excellent. Examples of the compound (f) having an unsaturated double bond used in the present invention include a (meth) acrylate monomer, a compound having a vinyl group and an ethynyl group, and the like.

The (meth) acrylate monomer used in the present invention includes ethylene glycol di (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 4-hydroxybutyl. (Meth) acrylate, 3-hydroxypropyl (meth) acrylate, tetraethylene glycol (meth) acrylate,
Examples thereof include tetrapropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, and ethyl (meth) acrylate. These can be used alone or in combination of two or more.

When comparing the acrylate monomer and the methacrylate monomer, the acrylate monomer is preferred because it has a higher efficiency of the Michael addition reaction. It is preferable to use a (meth) acrylate monomer having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, or 3-hydroxypropyl (meth) acrylate since the Michael addition reaction is accelerated.
(Meth) having a long-chain alkyl group such as butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate
The use of an acrylate monomer is preferred because the adhesion is improved, and the product after the Michael addition reaction is one in which an average of one active hydrogen of the amino group has reacted with (meth) acrylate.

In the Michael addition reaction between the polyamine (e) and the (meth) acrylate monomer, 1 mol of active hydrogen of the amino group of the polyamine (e) reacts with 1 mol of the double bond group of the (meth) acrylate monomer. Although the reaction proceeds even without a catalyst, the reaction proceeds at 60 to 100 ° C. while heating under a nitrogen atmosphere.
When the reaction is carried out at a suitable rate, an appropriate reaction rate is obtained. Preferably, the polyamine (e) and the (meth) acrylate are reacted in substantially equimolar amounts. As the compound having a vinyl group or an ethynyl group used in the present invention, vinyl acetate,
Vinyl butyrate, vinyl propionate, vinyl hexanoate,
Fatty acid vinyl compounds such as vinyl caprylate, vinyl laurate, vinyl palmitate and vinyl stearate, alkyl vinyl ether compounds such as butyl vinyl ether and ethyl vinyl ether, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1- Tetradecene, 1
Α-olefin compounds such as hexadecene, allyl compounds such as allyl acetate, allyl alcohol, allylbenzene and allyl cyanide, vinyl compounds such as styrene, vinyl cyanide, vinylcyclohexane and vinyl methyl ketone, acetylene, ethynylbenzene and ethynyltoluene And ethynyl compounds such as 1-ethynyl-1-cyclohexanol. These can be used alone or in combination of two or more.

In the Michael addition reaction of the polyamine (e) with a compound having a vinyl group or an ethynyl group, 1 mol of active hydrogen of the amino group of the polyamine (e) reacts with 1 mol of a vinyl group or an ethynyl group. Polyamine (e) is preferred as a compound having a vinyl group or an ethynyl group because it easily adds Michael to a vinyl group or an ethynyl group of a compound having an electron-withdrawing group.
Even a compound having no electron-withdrawing group can react in the presence of a metal catalyst. 60 to 10 with heating in the presence of a catalyst
The reaction at 0 ° C. is preferable because the reaction rate becomes appropriate. The polyamine (e) and the compound having a vinyl group or an ethynyl group are preferably reacted in substantially equimolar amounts.

As the compound (h) having an active hydrogen used in the present invention, a monoamine compound having a hydroxyl group is preferable, and 2-amino-2-methyl-propanol, 2-amino-2-methyl-propanol,
Aminopropanol, 3-aminopropanol and the like.

Urethane resin (C) prepared by chain extension reaction
Is obtained by blending a urethane prepolymer (A) having an isocyanato group at the end with a compound (g) obtained by subjecting a polyamine (e) and a compound (f) having an unsaturated double bond to a Michael addition reaction, Compound (h) having active hydrogen is
It reacts with the unreacted isocyanato group remaining at the end of the urethane resin (C) to stabilize the reaction activity of the resin. When the compound (h) having active hydrogen is 2-amino-2-methyl-propanol, both the amino group and the hydroxyl group can react with the terminal isocyanate group of the urethane resin (C). Is higher and reacts preferentially with isocyanate groups.

As the catalyst (c) used in the present invention, a known catalyst can be used. For example, tertiary amine compounds, organometallic compounds and the like can be mentioned.

Examples of the tertiary amine compound include triethylamine, triethylenediamine, N, N-dimethylbenzylamine, N-methylmorpholine, DBU and the like.

Examples of the organometallic compound include a tin compound and a non-tin compound. Examples of the tin compound include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, tributyltin acetate, Examples include triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate.

Examples of the non-tin compounds include titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate and butoxy titanium trichloride, and lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate and lead naphthenate. Iron, such as iron, 2-ethylhexanoate and iron acetylacetonate; cobalt, such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc, such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium naphthenate And the like.

The catalyst (c) used in the present invention includes:
Dibutyltin dilaurate (DBTDL), tin 2-ethylhexanoate and the like are preferable, and depending on the case, they can be used alone or in combination.

As the solvent used for the synthesis of the urethane prepolymer (A) of the present invention, known solvents can be used. Examples include methyl ethyl ketone, ethyl acetate, toluene, xylene, acetone and the like. Ethyl acetate and toluene are particularly preferred from the viewpoint of the solubility of the polyurethane urea resin and the boiling point of the solvent.

The urethane-forming reaction for producing the urethane prepolymer (A) by reacting the polyol (a) and the polyisocyanate (b) can be carried out by various methods. The reaction is roughly classified into 1) the case where the reaction is carried out by charging the whole amount, and 2) the method where the polyol (a) and the catalyst (c) are charged into a flask and the polyisocyanate (b) is added dropwise. 2) is preferred. The reaction temperature for obtaining the urethane prepolymer (A) is preferably 120 ° C. or lower. 1
When the temperature exceeds 20 ° C., the allohanate reaction proceeds, and the urethane prepolymer (A) having a predetermined molecular weight and structure cannot be obtained. More preferably, it is 70 to 110 ° C. 1
When the temperature exceeds 10 ° C., it becomes difficult to control the reaction rate, and it becomes impossible to obtain a urethane prepolymer (A) having a predetermined molecular weight and structure. The urethanization reaction is preferably performed at 70 to 110 ° C. for 2 to 20 hours in the presence of the catalyst (c).

The mixing ratio of the polyol (a) to the polyisocyanate (b) is such that the molar equivalent of the isocyano group of the polyisocyanate (b) is 1 with respect to the molar equivalent of the hydroxyl group of the polyol (a) of 1, so that the isocyanato group remains at the terminal. It must be greater than one. An appropriate compounding ratio largely depends on the reactivity of the compound, the abundance ratio of a compound having three or more valences, and the like.

A chain extension reaction for obtaining a urethane resin (C) from a compound (g) obtained by subjecting a urethane prepolymer (A), a polyamine (e) and a compound (f) having an unsaturated double bond to a Michael addition reaction is as follows: 1) A method in which a urethane prepolymer (A) solution is charged into a flask, and a compound (g) obtained by subjecting a polyamine (e) to a compound (f) having an unsaturated double bond to undergo a Michael addition reaction is dropped, 2) a polyamine ( The compound (g) solution obtained by subjecting e) and the compound (f) having an unsaturated double bond to a Michael addition reaction is charged into a flask, and the urethane prepolymer (A) solution is dropped. The synthesis is carried out in such a way that the reaction becomes stable, but if there is no problem in the reaction, the method 1) which is easy to operate is preferable. The temperature of the chain extension reaction of the present invention is preferably 100 ° C. or lower. If the temperature exceeds 100 ° C., the urethane prepolymer (A) having a predetermined molecular weight and structure cannot be obtained. More preferably, it is 70 ° C. or lower. The reaction rate is high even at 70 ° C., and if it cannot be controlled, the temperature is more preferably 50 ° C. or lower. If the temperature exceeds 50 ° C., it is difficult to control the reaction rate, and it is difficult to obtain a urethane resin (C) having a predetermined molecular weight and structure.

When the compound (h) having active hydrogen is added, the mixture is heated at 70 ° C. or lower after the completion of the chain extension reaction. 70
When the temperature exceeds ℃, the urethane prepolymer (A) having a predetermined molecular weight and structure cannot be obtained. The end point of the reaction is determined based on isocyanate% measurement and disappearance of the isocyanate peak by IR measurement.

The weight average molecular weight of the urethane resin (C) is:
The molecular weight in terms of standard polystyrene by GPC is preferably 10,000 or more. More preferably, it is 30,000 or more. If the weight-average molecular weight is 10,000 or less, the adhesive properties, especially the holding power, decrease remarkably, which is not preferable.

The urethane resin pressure-sensitive adhesive according to the present invention includes:
If necessary, another resin such as an acrylic resin, a polyester resin, an amino resin, an epoxy resin, or a polyurethane resin can be used in combination. In addition, depending on the application, a filler such as a tackifier, talc, calcium carbonate, titanium oxide, a coloring agent, an ultraviolet absorber, an antioxidant, an antifoaming agent, and an additive such as a light stabilizer may be blended. good.

A synthesis example is shown below. Synthesis Example 1 300 g of 2,2,4-trimethylhexamethylenediamine and 300 g of toluene were charged into a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel, and 198 g of 2-hydroxyethyl acrylate. 190 g of ethyl acrylate was added dropwise at room temperature. After the completion of the dropwise addition, the mixture was reacted at 80 ° C. for 1 hour, and then added with 388 g of toluene to obtain compound (1).

Synthesis Example 2 300 g of isophorone diamine was placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel.
300 g of toluene was charged, and 184 g of 2-hydroxyethyl acrylate and 176 g of ethyl acrylate were added dropwise at room temperature. After the completion of the dropwise addition, the mixture was reacted at 80 ° C. for 1 hour, and 360 g of toluene was added thereto to obtain a compound (2).

Synthesis Example 3 Polyether polyol PP was placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a thermometer, and a dropping funnel.
2000 (bifunctional polyether polyol, OH value 5
6, 257 g of Sanyo Kasei Kogyo Co., Ltd., and 43 of isophorone diisocyanate (manufactured by Huls Japan KK)
g, 75 g of toluene and 0.05 g of dibutyltin dilaurate as the catalyst (c) were gradually heated to 100 ° C. and reacted for 2 hours. After confirming the remaining amount of the isocyanate group by titration, the mixture was cooled to 40 ° C., 160 g of ethyl acetate was added, 40 g of the compound (1) was added dropwise over 1 hour, and the mixture was aged for 1 hour. The reaction was terminated by adding 20 g of methyl-propanol (manufactured by Nagase & Co., Ltd.). The reaction solution was colorless and transparent, had a solid content of 50%, and had a viscosity of 4%.
000 cps, number average molecular weight MN 23,000, and weight average molecular weight MW 75,000.

Synthesis Example 4 Polyether polyol PP was placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a thermometer, and a dropping funnel.
2000 (bifunctional polyether polyol, OH value 5
6, 257 g of Sanyo Kasei Kogyo Co., Ltd., and 43 of isophorone diisocyanate (manufactured by Huls Japan KK)
g, 75 g of toluene and 0.05 g of dibutyltin dilaurate as the catalyst (c) were gradually heated to 100 ° C. and reacted for 2 hours. After confirming the remaining amount of the isocyanato group by titration, the mixture was cooled to 40 ° C., 160 g of ethyl acetate was added, 40 g of compound (2) was added dropwise over 1 hour, and the mixture was aged for 1 hour. The reaction was terminated by adding 20 g of methyl-propanol (manufactured by Nagase & Co., Ltd.). The reaction solution was colorless and transparent, the solid content was 50%, and the viscosity was 3
The number average molecular weight was 500 cps, the number average molecular weight was 25,000, and the weight average molecular weight was MW 80,000. Synthesis Example 5 Polyether polyol PP- was placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel.
2000 (bifunctional polyether polyol, OH value 5
6, 279 g of Sanyo Kasei Kogyo Co., Ltd., and isophorone diisocyanate (manufactured by Huls Japan KK) 21
g, 75 g of toluene and 0.05 g of dibutyltin dilaurate as the catalyst (c) were gradually heated to 100 ° C. and reacted for 2 hours. Cool to room temperature and add ethyl acetate 2
The reaction was terminated by adding 25 g. The reaction solution was colorless and transparent, the solid content was 50%, the viscosity was 300 cps, and the number average molecular weight was M.
N 10,000 and weight average molecular weight MW 20,000. Synthesis Example 6 Polyether polyol PP- was placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel.
2000 (bifunctional polyether polyol, OH value 5
6, 257 g of Sanyo Kasei Kogyo Co., Ltd., and 43 of isophorone diisocyanate (manufactured by Huls Japan KK)
g, 75 g of toluene and 0.05 g of dibutyltin dilaurate as the catalyst (c) were gradually heated to 100 ° C. and reacted for 2 hours. After confirming the remaining amount of the isocyanato group by titration, the mixture was cooled to 40 ° C., 160 g of ethyl acetate was added, and 40 g of the compound (2) was added dropwise over 1 hour to complete the reaction. This reaction solution was colorless and transparent, had a solid content of 50%, a viscosity of 3500 cps, a number average molecular weight MN of 22,000 and a weight average molecular weight of MW 75,000.

[0069]

EXAMPLE 1 2 g of a curing agent (C) was added to 100 g of the urethane resin solution synthesized in Synthesis Example 3, and an antioxidant (i) was further added.
Was mixed with 0.5 g of the ultraviolet absorber (j) and 0.5 g of the light stabilizer (k), and tested for adhesion and weather resistance by the following methods. The curing agent (C) is a hexamethylene diisocyanate trimethylolpropane adduct 75
% Ethyl acetate solution was used. Antioxidant (i) is IR
GANOX L135 (Ciba Special Chemicals Co., Ltd.) was used. UV absorber (j) is TINU
VIN 571 (Ciba Specialty Chemicals) was used. Light stabilizer (k) is TINUVIN
765 (Ciba Specialty Chemicals Co., Ltd.)
Was used.

The test method is as follows. <Coating method> The above-mentioned polyurethane urea resin solution was coated on a release paper with an applicator so as to have a dry coating film of 25 μm, and dried at 100 ° C. for 2 minutes to prepare a coated product. After one week at room temperature, it was used for the following measurements. <Adhesive force> An adhesive sheet obtained by coating a polyurethane urea resin solution on a release paper was transferred to a polyethylene terephthalate film (25 μm in thickness), and was placed on a 0.4 mm thick stainless steel plate (SUS304) at 23 ° C. and 65% RH. After 20 minutes of roll-press bonding according to JIS, the peel strength (180 peel, pulling speed 300 mm / min; unit g / 25 mm width) was measured with a shopper type peel tester. <Weather resistance> After sticking a pressure-sensitive adhesive sheet obtained by applying a polyurethane urea resin solution to a release paper to a stainless steel plate (SUS304) or a glass plate, irradiating with a sunshine weatherometer (Suga Test Instruments Co., Ltd.) for 300 hours , Peeled off, and adhesive residue was visually evaluated. After peeling, there was no adhesive transfer to the adherend at all. ご Very slight thing ○ Partially present △ Completely transferred ×

Examples 2 to 10 Comparative Examples 1 and 2 The urethane resins were changed to those shown in Table 1, and a curing agent (C), an antioxidant (i), an ultraviolet absorber (j), and a light stabilizer ( The same operation as in Example 1 was performed after changing the addition amount of k) as shown in Table 1.

Table 2 shows the urethane resin pressure-sensitive adhesive compositions, adhesion, and weather resistance test results of Examples 1 to 10 and Comparative Examples 1 and 2.

[0073]

[Table 1]

[0074]

[Table 2]

The weather resistance of a urethane resin pressure-sensitive adhesive containing a deterioration inhibitor (d) (an antioxidant (i), an ultraviolet absorber (j), and a light stabilizer (k)) is applicable to both a stainless steel plate and a glass plate. It is also good when it is set to. On the other hand, Comparative Example 1,
The urethane resin pressure-sensitive adhesive not containing the deterioration inhibitor (d) shown in No. 2 has poor weather resistance. Examples 2 to 4, 6
And urethanes containing only an antioxidant (i) as a deterioration inhibitor (d) or a blend of an antioxidant (i) with an ultraviolet absorber (j) or a light stabilizer (k) The weather resistance of the resin pressure-sensitive adhesive was better than that of the comparative example. The weather resistance of the urethane resin adhesive containing all of the antioxidant (i), the ultraviolet absorber (j) and the light stabilizer (k) was even better.

[0076]

According to the present invention, an adhesive having excellent weather resistance can be obtained by blending a deterioration inhibitor (d) (an antioxidant (i), an ultraviolet absorber (j), and a light stabilizer (k)) with a urethane resin. Can be obtained.

Continued on the front page F-term (reference) 4J034 BA06 CA02 CA03 CA04 CA05 CA13 CA22 CB01 CB03 CB04 CB08 CC12 CC23 CC26 CC34 CC45 CC52 CC61 CC62 CC65 CC67 CE03 DF01 DF11 DF12 DF16 DF20 DF21 DF22 DG02 HG03 HC17 HA12 HC22 HC26 HC35 HC45 HC46 HC52 HC61 HC64 HC67 HC70 HC71 HC73 JA42 KA01 KB02 KC17 KD02 KD04 KD05 KD12 KD21 KD25 KD27 KE02 RA08 4J040 EF061 EF111 EF131 EF321 FA122 HB19 HB36 HB40 HC01 HC25 HD05 HD24 J

Claims (7)

[Claims] An urethane resin pressure-sensitive adhesive containing a urethane resin (B) and a deterioration inhibitor (d), wherein the urethane resin (B) comprises a polyol (a) and a polyisocyanate (b) as a catalyst (c). A) a urethane resin pressure-sensitive adhesive which is a urethane prepolymer (A) reacted in the presence of). 2. A urethane resin pressure-sensitive adhesive containing a urethane resin (C) and a deterioration inhibitor (d), wherein the urethane resin (C) comprises a polyol (a) and a polyisocyanate (b) as a catalyst (c). ) Is reacted with a compound (g) obtained by subjecting a polyamine (e) to a compound (f) having an unsaturated double bond to undergo a Michael addition reaction. A urethane resin adhesive characterized by the following. 3. A urethane resin (C ″) and a deterioration inhibitor (d)
And a urethane resin (C "), wherein the urethane resin (C") reacts the polyol (a) with the polyisocyanate (b) in the presence of the catalyst (c) to form a urethane prepolymer (A). A polyamine (e) and a compound (f) having an unsaturated double bond are subjected to a Michael addition reaction, and a chain-extended urethane resin (C ′) having an isocyanate group at the terminal is further added to the isocyanate. A urethane resin pressure-sensitive adhesive obtained by reacting a compound (h) having an active hydrogen capable of reacting with a group. 4. The urethane resin pressure-sensitive adhesive according to claim 1, wherein the deterioration inhibitor (d) contains an antioxidant (i). 5. An antioxidant (i) wherein the deterioration inhibitor (d) is an antioxidant (i).
The urethane resin pressure-sensitive adhesive according to any one of claims 1 to 4, further comprising an ultraviolet absorber (j) or a light stabilizer (k). 6. The antioxidant (i), wherein the antioxidant (d) is
The urethane resin pressure-sensitive adhesive according to any one of claims 1 to 5, further comprising an ultraviolet absorber (j) and a light stabilizer (k). 7. A first step of reacting a polyol (a) and a polyisocyanate (b) in the presence of a catalyst (c) to synthesize a urethane prepolymer (A), wherein the urethane prepolymer (A) is A second example of synthesizing a urethane resin (C ′) having a terminal isocyanate group by chain extension with a compound (g) obtained by subjecting a polyamine (e) and a compound (f) having an unsaturated double bond to a Michael addition reaction, A third step of synthesizing a urethane resin (C ″) by reacting the urethane resin (C ′) having an isocyanato group at the terminal with a compound (h) having an active hydrogen capable of reacting with the isocyanato group; And a method for producing a urethane resin pressure-sensitive adhesive, comprising a fourth step of blending a deterioration inhibitor (d) with the urethane resin (C ″).