JPH11199634A - Vinyl alcohol-based polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject polymer containing structural unit consisting of diazonium salt group, and suitable as e.g. a photosensitive material. SOLUTION: This polymer contains pref. 0.01-30 mol.% of structural unit consisting of diazonium salt group and pref. shown by the formula (R<1> to R<5> are each H or a <=8C hydrocarbon; A is a bivalent hydrocarbon; S is a sulfur atom; X is a monoalent group containing diazonium salt group), and is obtained, pref. by reaction of a vinyl alcohol-based polymer bearing a primary amino group bound to phenyl group with a nitrite salt under acidic conditions to effect diazotization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel vinyl alcohol-based polymer.

[0002]

2. Description of the Related Art Polyvinyl alcohol (hereinafter sometimes abbreviated as PVA) is used as a stabilizer for paper processing, fiber processing and emulsion because of its excellent interfacial properties and strength properties. I have. Also, PV
A occupies an important position as a raw material for molded products such as films and fibers. On the other hand, high functionality is pursued by controlling the crystallinity of PVA or by introducing a functional group, and various modified PVAs have been developed. Under such circumstances, a photosensitive material comprising PVA and a diazonium compound or a dichromate has good properties of a photosensitive film obtained by using the same, and it is easy to wash and remove unexposed portions with water. Therefore, it is used as an emulsion for screen printing plate making. Recently, in the electronics field, the development of fine devices has been remarkable,
There is a demand for photosensitive materials and plate-making materials capable of forming very fine images. Therefore, compared with the conventional photosensitive material, a thin film can be formed, the exposed portion is strongly adhered to the substrate, the water resistance and chemical resistance are further improved, and the removal of the unexposed portion is improved. Are required. On the other hand, the photosensitive material using the conventional PVA has a disadvantage that when the uncured portion is washed away with water after exposure (at the time of development), a part of the cured portion of PVA is removed, For this reason, there has been a problem that the properties of the completed printing plate material are impaired.

[0003]

Under such circumstances, an object of the present invention is to provide a vinyl alcohol polymer suitable for a photosensitive material or the like.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found a vinyl alcohol-based polymer containing a constitutional unit composed of a diazonium base, and have completed the present invention. Was.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The diazonium base contained in the molecule of the vinyl alcohol polymer of the present invention includes an aromatic diazonium base and a chain diazonium base, and an aromatic diazonium base is more preferable. As the content of the structural unit consisting of a diazonium base,
It is preferably 0.01 to 30 mol%, more preferably 0.02 to 20 mol%, and particularly preferably 0.05 to 15 mol%. When the content of the structural unit is less than 0.01 mol%, the effect of introduction is not sufficient, and when it exceeds 30 mol%, the storage stability of the vinyl alcohol-based polymer decreases.

As a structural unit comprising a diazonium base, a structural unit represented by the following chemical formula 2 is preferable. There is no particular limitation on the distribution of the constituent units in the vinyl alcohol-based polymer.

[0007]

Embedded image

(Where R ¹ , R ² , R ³ , R ⁴ and R ⁵
Represents a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms;
Represents a divalent hydrocarbon group, S represents a sulfur atom, and X represents a monovalent group containing a diazonium base. )

R ¹ , R ² , R in the structural unit represented by Chemical Formula ^2
3 , R ⁴ and R ⁵ are a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms which may have a substituent. In a preferred embodiment, R ¹ is a hydrogen atom, R ² is a hydrogen atom or a methyl group, and R ³ , R ⁴ and R ⁵ are a hydrogen atom or a carbon atom having 8 or less (preferably 6 or less) carbon atoms. Hydrogen groups are preferred. Note that R ³ and R ⁴ (or R ⁵ ) may form a ring together.

A in the structural unit represented by Chemical Formula 2 is a divalent hydrocarbon group which may contain a nitrogen atom, an oxygen atom or a sulfur atom. As a specific example,-(CH ₂ ) _n-
(N = 1 to 10, preferably 1 to 8), —CH ₂ OCH
_{2 -, - OCH 2 -,} - CONH-ph-OCH 2 -, -
CONHCH ₂ —, —CONHCH ₂ OCH ₂ —, —CO
_{NHCH 2 OCH 2 CH 2 -,} - CONHCH 2 OCH 2 C
_{H 2 CH 2 -, - CONHCH} 2 OCH 2 CH 2 CH 2 CH 2
—, —CONHCH ₂ —ph (CH ₃ ) ₂ —CH ₂ — and the like. (In addition, ph means a phenyl group.)

X in the structural unit represented by Chemical Formula 2 is a monovalent group containing a diazonium base bonded to a phenyl group (which may be a substituted phenyl group). As specific examples, -ph-N≡N ⁺ (1,2-), -ph-N≡N ⁺
(1,3-), -ph-N≡N ⁺ (1,4-), -CH ₂
-Ph-N≡N ⁺ (1,2-), -CH ₂ -ph-N≡N
⁺ (1,3-), -CH ₂ -ph-N≡N ⁺ (1,4
-), -CH ₂ CH ₂ -ph-N≡N ⁺ (1,2-),-
CH ₂ CH ₂ -ph-N≡N ⁺ (1,3-), -CH ₂ CH
₂ -ph-N≡N ⁺ (1,4-), -ph (CH ₃ ) -N
{ ^{N +} (1,2,3-), -ph (CH ₃ ) -N} N
⁺ (1,2,4-), -ph (CH ₃ ) -N≡N ⁺ (1,
2,5-), -ph (CH ₃ ) -N≡N ⁺ (1,2,6
−), -Nph-N≡N ⁺ (1,2-), -nph-N
^{≡N + (1,4 -), -} nph-N≡N + (1,8-) , and the like. (Where ph represents a phenyl group, n
ph means a naphthalene group. ) When there are two numbers in parentheses, the first number is -S
Indicates the position where-is bonded (in all cases, 1), and the second number indicates the position where the -N≡N ⁺ group is bonded (the position where -S- is bonded to the phenyl group). 1). When there are three numbers in the parentheses, the first number indicates a position where -S- is bonded to the phenyl group (in all cases, 1), and the second number indicates another position. And the third number is -N≡N
⁺ Indicates the position where the group is bonded.

The vinyl alcohol-based polymer of the present invention comprises a vinyl alcohol unit or a vinyl alcohol unit and a vinyl ester unit, excluding a diazonium base constituent unit. Examples of the vinyl ester unit include vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl trifluoroacetate, and vinyl 2-ethylhexanoate.

The vinyl alcohol polymer of the present invention may contain other monomer units. Examples of such units include olefins such as ethylene, propylene, 1-butene, and isobutene; and non-olefins such as acrylic acid, methacrylic acid, crotonic acid, (anhydrous) phthalic acid, (anhydrous) maleic acid, and (anhydrous) itaconic acid. Saturated acids or salts thereof or mono- or dialkyl esters having 1 to 18 carbon atoms; acrylamide, N- having 1 to 18 carbon atoms;
Acrylamides such as alkylacrylamide, N, N-dimethylacrylamide, 2-acrylamidopropanesulfonic acid or a salt thereof, acrylamidopropyldimethylamine or an acid salt thereof or a quaternary salt thereof; methacrylamide, an N-alkyl having 1 to 18 carbon atoms Methacrylamides such as methacrylamide, N, N-dimethylmethacrylamide, 2-methacrylamidopropanesulfonic acid or a salt thereof, methacrylamidopropyldimethylamine or an acid salt thereof or a quaternary salt thereof; N-vinylpyrrolidone, N-vinyl N-vinylamides such as formamide and N-vinylacetamide; vinyl cyanides such as acrylonitrile and methacrylonitrile; alkyl vinyl ethers having 1 to 18 carbon atoms; Vinyl ethers such as vinyl ether, alkoxyalkyl vinyl ether; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, and vinyl bromide; vinyl silanes such as trimethoxy vinyl silane; allyl acetate, allyl chloride, allyl alcohol , Dimethylallyl alcohol, trimethyl- (3-acrylamido-3-dimethylpropyl) -ammonium chloride, acrylamide-
2-methylpropane sulfonate and the like.

The viscosity-average degree of polymerization (hereinafter abbreviated as polymerization degree) of the vinyl alcohol polymer of the present invention is not particularly limited, but is preferably from 100 to 8000, and more preferably from 200 to 200.
0 is more preferred. The content of vinyl alcohol unit is 1
0-99.9 mol% is preferable, and 50-99.9 mol%.
Is more preferred.

As a method for producing the vinyl alcohol polymer of the present invention, a method in which a vinyl alcohol polymer containing a primary amino group bonded to a phenyl group is reacted with nitrite under acidic conditions to diazotize the vinyl alcohol polymer. Is mentioned. The vinyl alcohol polymer containing a primary amino group bonded to the phenyl group is obtained by adding a thiol having a primary amino group bonded to a phenyl group to a copolymer of a vinyl ester monomer and a vinyl monomer having an epoxy group. It is obtained by hydrolysis after the reaction.

The vinyl monomer having an epoxy group used for copolymerization of a vinyl ester monomer and a vinyl monomer having an epoxy group includes allyl glycidyl ether, methacryl glycidyl ether, 1,2-epoxy-5-hexene, 2-epoxy-7-octene, 1,2-epoxy-9-decene, 8-hydroxy-
6,7-epoxy-1-octene, 8-acetoxy-
6,7-epoxy-1-octene, N- (2,3-epoxy) propylacrylamide, N- (2,3-epoxy) propylmethacrylamide, 4-acrylamidophenylglycidyl ether, 3-acrylamidophenylglycidylether, 4 -Methacrylamidophenyl glycidyl ether, 3-methacrylamidophenyl glycidyl ether, N-glycidoxymethyl acrylamide, N-glycidoxymethyl methacrylamide, N-
Glycidoxyethyl acrylamide, N-glycidoxyethyl methacrylamide, N-glycidoxypropyl acrylamide, N-glycidoxypropyl methacrylamide, N-glycidoxybutyl acrylamide, N-glycidoxybutyl methacrylamide, 4 Acrylamidomethyl-2,5-dimethyl-phenylglycidyl ether, 4-methacrylamidomethyl-2,5-dimethyl-phenylglycidylether, acrylamidopropyldimethyl (2,3-epoxy) propylammonium chloride, methacrylamidopropyldimethyl (2 , 3
-Epoxy) propylammonium chloride, glycidyl methacrylate and the like.

The method of copolymerizing the vinyl ester monomer and the vinyl monomer having an epoxy group includes known methods such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization. Among them, a bulk polymerization method or a solution polymerization method in which polymerization is performed without a solvent or in a solvent such as an alcohol is usually employed. In order to obtain a polymer having a high degree of polymerization, an emulsion polymerization method is employed. Examples of the alcohol used as a solvent during the solution polymerization include lower alcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol. Examples of the initiator used for the copolymerization include, for example, α, α′-azobisisobutyronitrile,
Azo-based compounds such as 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), benzoyl peroxide, and n-propylperoxycarbonate Known initiators such as an initiator or a peroxide-based initiator can be used. The polymerization temperature is not particularly limited, but is preferably in the range of -30 to 150 ° C.

The thiol having a primary amino group bonded to a phenyl group to be reacted with a copolymer of a vinyl ester monomer and a vinyl monomer having an epoxy group includes:
A compound containing a primary amino group bonded to a mercapto group and a phenyl group,
Aminothiophenol, 4-aminothiophenol and the like can be mentioned. Further, esters such as these acetates and benzoates can also be used.

A method for producing a vinyl alcohol-based polymer containing a primary amino group bonded to a phenyl group includes a reaction between a thiol group or a thioester group and an epoxy group. The reaction is carried out without a solvent or in a solvent that dissolves or swells a compound having a thiol group or a thioester group and a compound having an epoxy group. Examples of such a solvent include alcohols such as methanol, ethanol and n-butyl alcohol; aromatics such as benzene, toluene and xylene; ethers such as tetrahydrofuran, dioxane and diethyl ether; and hydrocarbons such as n-hexane. Is mentioned. These solvents are used alone or as a mixture. The reaction conditions are
Depending on the structure of the epoxy group and the structure of the thiol or thioester, when a solvent is used, the polymer concentration is 5 to 90%, and the concentration of the thiol group or thioester group / epoxy group concentration is 1.0 to 5.0 (mol Ratio), the reaction temperature is 0 to 250 ° C., and the reaction time is 0.01 to 20 hours. Here, in the reaction with thiol, a tertiary amine (eg, triethylamine, pyridine, etc.), a phosphine (eg, tributylphosphine, triphenylphosphine, etc.),
Basic compounds such as sodium hydroxide, sodium acetate, tetraethylammonium hydroxide and sodium methylate are effective as reaction catalysts, and quaternary ammonium salts such as tributylammonium chloride and tributylammonium bromide are used as reaction catalysts in the reaction with thioesters. It is valid. In order to prevent thiol oxidation, the reaction system may be degassed or replaced with nitrogen, or an antioxidant may be added.

For the hydrolysis subsequent to the reaction between the thiol group or the thioester group and the epoxy group, a saponification reaction using a basic catalyst or an acid catalyst, which is commonly used in the saponification of polyvinyl esters, can be applied. That is, sodium hydroxide, potassium hydroxide, using a basic catalyst such as sodium methylate or an acidic catalyst such as p-toluenesulfonic acid, methanol, ethanol, propanol, butanol, alcohol and glycol such as ethylene glycol as a solvent. The reaction takes place. In this case, in order to improve the solubility of the vinyl ester polymer or the catalyst, terahydrofuran, dioxane, dimethyl sulfoxide,
Solvents such as diethylene glycol dimethyl ether, toluene, acetone, and water are appropriately mixed and used. The conditions of the saponification reaction are appropriately adjusted depending on the structure of the vinyl ester polymer to be used and the degree of saponification of the intended vinyl alcohol polymer. Usually, saponification is carried out at a catalyst concentration / vinyl ester unit concentration (molar ratio) = 0.001-1.2,
The reaction is carried out at a reaction temperature of 20 to 180 ° C and a reaction time of 0.1 to 20 hours.

The diazonium base-containing vinyl alcohol polymer of the present invention can be obtained by diazotizing an amino group in a vinyl alcohol polymer having a primary amino group bonded to a phenyl group. The nitrite used for the diazotization is not particularly limited, but usually sodium nitrite is used. The diazotization reaction is carried out in an aqueous solution or a solution capable of swelling PVA such as alcohols. Usually, the reaction is performed at a reaction temperature of 10 ° C. or lower and a reaction time of 0.01 to 20 hours.

The diazonium base-containing vinyl alcohol-based polymer of the present invention utilizes the reactivity of the diazonium base to produce a photosensitive material, a fiber paste, a fiber treatment agent, a fiber processing agent, a binder for a paper coating agent, Paper processing agents such as binders for overcoating thermal paper, dispersants for organic and inorganic pigments, binders for ceramics, image forming materials,
It is used as a raw material for polyvinyl acetal such as formal resin and butyral resin, a base material for gel, a film and the like. In addition, the vinyl alcohol-based polymer containing a diazonium base of the present invention can be used alone or in combination with other components. Other components include unmodified PVA,
Other modified PVA, starch (and its modified products), cellulose derivatives, gums, gelatin, casein, and other various polymers, and plasticizers are exemplified. When used as a photosensitive composition, it is used in combination with a radically polymerizable unsaturated compound and a compound such as a photopolymerization initiator. Further, a diazonium compound, a dichromate or the like can be used in combination.

[0023]

The present invention will be described in more detail with reference to the following synthetic examples, but the present invention is not limited to these synthetic examples. In addition, "part" and "%" in the synthesis examples mean weight basis unless otherwise specified.

Synthesis Example 1 (Synthesis of PVA containing diazonium base) (1) Synthesis example of vinyl acetate polymer having epoxy group Acetic acid was added to a reactor equipped with a stirrer, a reflux condenser, a nitrogen inlet tube and a thermometer. 405 parts of a vinyl monomer, 11 parts of allyl glycidyl ether and 30 parts of methanol were charged, and nitrogen gas was bubbled for 15 minutes to degas. Separately, an initiator solution prepared by dissolving 4.5 parts of 2,2′-azobisisobutyronitrile in 15 parts of methanol was prepared, and nitrogen was replaced by bubbling with nitrogen gas. Start heating the reactor,
When the internal temperature reached 60 ° C., a separately adjusted initiator solution was added to initiate polymerization. After polymerization at 60 ° C. for 4 hours, the polymerization was stopped by cooling. The solid concentration at this time is 5
It was 4.8%. Subsequently, unreacted vinyl acetate monomer was removed while occasionally adding methanol at 30 ° C. under reduced pressure to obtain a methanol solution of polyvinyl acetate copolymer (concentration: 44.5%). A part of this methanol solution was put into ether to recover the polymer, which was purified by reprecipitation twice with acetone-ether, and then dried at 40 ° C. under reduced pressure. The purified polymer was subjected to proton NMR (GSX-270, manufactured by JEOL Ltd.) and intrinsic viscosity measurement in acetone (JIS) using CDCl ₃ as a solvent, and the viscosity average molecular weight was calculated. As a result, allyl glycidyl ether units (epoxy Is a vinyl acetate polymer having a viscosity average molecular weight of 80 × 10 ³ containing 2.1 mol% of

(2) PVA containing amino group (aniline group)
In a reactor equipped with a stirrer, a reflux condenser, a nitrogen inlet tube and a thermometer, a methanol solution of the vinyl acetate polymer having an epoxy group obtained in the above (1) (concentration: 44.5%) 1
After measuring 00 parts and bubbling nitrogen gas for 15 minutes,
A solution prepared by dissolving 8.0 parts of 2-aminothiophenol and 0.03 part of sodium hydroxide in 48 parts of methanol was charged. After reacting at 50 ° C for 2 hours with stirring, 40 ° C
And cooled. Next, a saponification reaction was performed by adding 20 parts of a methanol solution of sodium hydroxide having a concentration of 10% and leaving the mixture at 40 ° C. for 5 hours. The obtained product was pulverized and neutralized by adding 8 parts of acetic acid. Next, washing with methanol for 48 hours or more using a Soxhlet extractor,
By drying at 20 ° C. for at least 20 hours, an amino group (aniline group) -containing PVA was obtained. The polymer is 2.1 mol%
Is introduced, the content of vinyl alcohol units is 91.0 mol%, and the degree of polymerization is 100.
It was 0. When an ultraviolet absorption spectrum of PVA containing an amino group (aniline group) was measured, a peak derived from the amino group (aniline group) was observed.

(3) Synthesis example of PVA containing diazonium base Amino group (aniline group) -containing PVA obtained in the above (2)
1 part of tartaric acid is added to 100 parts of a 10% aqueous solution of A, the aqueous solution is cooled to 5 ° C. while stirring, and 3 parts of sodium nitrite is added to carry out diazotization to obtain a diazonium base-containing PVA. I got When the ultraviolet absorption spectrum of the diazonium base-containing PVA was measured, the peak derived from the amino group (aniline group) disappeared, and a new peak derived from the diazonium base was observed. When this aqueous solution of diazonium base-containing PVA was allowed to stand under sunlight, nitrogen bubbles were generated and gelled in 1 hour. From these phenomena, it was confirmed that a diazonium base was introduced into PVA.

[0027]

The vinyl alcohol polymer containing a diazonium base according to the present invention is easily crosslinked (gelled) by irradiation with ultraviolet rays, and exhibits remarkable water resistance, and thus is useful for photosensitive compositions and the like. It is.

[Brief description of the drawings]

FIG. 1 is an ultraviolet absorption spectrum of PVA containing an amino group (aniline group) and PVA containing a diazonium base.
The peak around 310 nm is due to the aniline group, and the peak around 400 nm is due to the diazonium base.

Claims (3)

[Claims] 1. A vinyl alcohol-based polymer containing a structural unit comprising a diazonium base. 2. A vinyl alcohol polymer containing from 0.01 to 30 mol% of a structural unit comprising a diazonium base. 3. The vinyl alcohol polymer according to claim 2, wherein the structural unit comprising a diazonium base is a structural unit represented by the following chemical formula 1. Embedded image (Where R ¹ , R ² , R ³ , R ⁴ and R ⁵ represent a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms, A represents a divalent hydrocarbon group, and S represents a sulfur atom. , X represents a monovalent group containing a diazonium base.)