JPH09157479A - Acrylamide water-soluble polymer aqueous solution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject thermally stabilized aqueous solution, capable of preventing the changes of viscosity and maintaining the quality for a long period, and useful as a water-soluble resist material by adding hydrochloric acid and thiourea to a water-soluble acrylamide polymer aqueous solution. SOLUTION: (B) Hydrochloric acid and (C) thiourea are added to (A) the aqueous solution of a water-soluble acrylamide polymer. The polymer of the component A is preferably a water-soluble acrylamide-diacetoneacrylamide polymer containing 1.5-4.0 moles of the acrylamide per mole of the diacetoneacrylamide. The components B and C are added in amounts of 0.1-5 pts.wt., preferably 0.2-1 pt.wt., and 0.1-5 pts.wt., preferably 0.2-2 pts.wt., respectively per 100 pts.wt. of the component A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermally stabilized acrylamide-based water-soluble polymer aqueous solution, and particularly to an acrylamide-based water-soluble polymer aqueous solution suitable as a water-soluble resist material.

[0002]

2. Description of the Related Art Acrylamide-based water-soluble polymers are high-molecular-weight water-soluble polymers and are therefore widely used in the fields of flocculants, papermaking chemicals, petroleum recovery chemicals, and the like. Also in the field of water-soluble resists, from the viewpoint of solubility in water, high molecular weight, etc., they are mainly used in the form of an aqueous solution and widely used for pattern formation, particularly for producing a black matrix of a color cathode ray tube. Red, blue, and green phosphors are regularly arranged on the inner surface of a glass panel of a color cathode-ray tube, and a light absorbing material called a black matrix is buried between the phosphors without any gap. Pattern formation by a resist is used to form this black matrix, and an acrylamide water-soluble polymer is used as a base resin of the resist.

However, the aqueous solution of the acrylamide-based water-soluble polymer undergoes a viscosity change due to the decomposition of the polymer over time, and the quality deteriorates. In particular, the tendency is remarkable in a heated state, and in some cases, the desired performance may not be achieved. In order to eliminate such disadvantages, various stabilizers have been proposed. For example, organic salts of dithiocarbamates (JP-A-62-17705).
2), 2-mercapto-2-thiazolines (JP-A-62-62)
-184047) and the like.

[0004]

The inventions of claims 1 and 2 provide an aqueous solution of an acrylamide-based water-soluble polymer that does not cause a change in viscosity at room temperature or under heating.

[0005]

The present invention relates to an acrylamide-based water-soluble polymer aqueous solution obtained by adding hydrochloric acid and thiourea to an acrylamide-based water-soluble polymer aqueous solution. The present invention also relates to the acrylamide-based water-soluble polymer aqueous solution, wherein the acrylamide-based water-soluble polymer is an acrylamide-diacetone acrylamide-based water-soluble polymer.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the acrylamide water-soluble polymer used in the present invention include polymers or copolymers of acrylamide alone. Examples of the copolymerizable monomer include acrylic acid, methacrylic acid, methacrylamide, diacetone acrylamide, and N-methylol acrylamide. The copolymerization ratio of acrylamide and other monomer is not particularly limited, but from the viewpoint of water solubility of the polymer, other monomer is used in an amount of 50 mol% or less based on the total amount of the monomers. Preferably. Although the molecular weight of the acrylamide-based water-soluble polymer is not particularly limited, it is generally used in the range of several hundreds of thousands to several millions. As the acrylamide-based water-soluble polymer, acrylamide-diacetone acrylamide-based water-soluble polymer is preferable in order to surely obtain the intended effect. This acrylamide-diacetone acrylamide-based water-soluble polymer preferably contains 1.5 to 4.0 mol of acrylamide as a constituent component with respect to 1 mol of diacetone acrylamide.

Of the two components used as the stabilizer in the present invention, the addition amount of hydrochloric acid is preferably in the range of 0.1 to 5 parts by weight, based on 100 parts by weight of the acrylamide water-soluble polymer, and 0.2 The range of 1 to 1 part by weight is more preferable. If it is less than 0.1 part by weight, the effect of suppressing the change in viscosity tends to be small, and if it exceeds 5 parts by weight, it is not economical for the effect. The addition amount of thiourea is preferably 0.1 to 5 parts by weight, more preferably 0.2 to 2 parts by weight, based on 100 parts by weight of the acrylamide water-soluble polymer. If it is less than 0.1 part by weight, the effect of suppressing the change in viscosity tends to be small, and if it exceeds 5 parts by weight, the effect is saturated and side effects can be considered. Hydrochloric acid and thiourea can be added in any form to the aqueous acrylamide-based aqueous polymer solution. Hydrochloric acid can be added as a stock solution (concentrated hydrochloric acid) or diluted to any concentration, and thiourea can be added as a powder or an aqueous solution. When the aqueous solution of the acrylamide water-soluble polymer has a high viscosity, it is more effective to add hydrochloric acid and thiourea and then mix and stir with an appropriate stirrer.

[0008]

EXAMPLES The present invention will now be described with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Those expressed as "parts" indicate parts by weight.

Comparative Example 1 An aqueous solution A was obtained by mixing and stirring 5 parts of polyacrylamide and 95 parts of ion-exchanged water. Comparative Example 2 5 parts of an acrylamide-diacetone acrylamide copolymer (copolymerization ratio; 1 mol of diacetone acrylamide to 2 mol of acrylamide) and 95 parts of ion-exchanged water were mixed and stirred to obtain an aqueous solution B.

Example 1 To 100 parts of the aqueous solution A of Comparative Example 1, 0.5 part of 0.5 mol / liter hydrochloric acid and 0.01 part of thiourea were added and mixed with stirring to obtain an aqueous solution C. Example 2 To 100 parts of the aqueous solution B of Comparative Example 2, 0.5 parts of 0.5 mol / liter hydrochloric acid and 0.01 part of thiourea were added and mixed with stirring to obtain an aqueous solution D.

The aqueous solutions A to D obtained above were treated at 23 ° C. and 4
Leave in a constant temperature bath at 0 ° C.
The viscosity after day was measured at 25 ° C. using a B-type viscometer (manufactured by Shibaura System Co., Ltd.). From these measured values, the viscosity retention rate was calculated by the following formula.

(Equation 1)

[0012]

[Table 1]

[0013]

EFFECTS OF THE INVENTION The acrylamide water-soluble polymer according to the present invention can prevent the viscosity change of the aqueous solution at room temperature and in the heated state, and can maintain the quality for a long time.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yoshiyuki Odaka, 3300 Hayano, Mobara-shi, Chiba Electronic device division, Hitachi, Ltd. (72) Masahiro Nishizawa, 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic device (72) Inventor Nobuaki Hayashi 1-280 Higashi Koigakubo, Kokubunji, Tokyo Inside Central Research Laboratory, Hitachi, Ltd. (72) Inventor Masato Ito 1-280 Higashi Koigakubo, Kokubunji, Tokyo Inside Central Research Laboratory, Hitachi (72) ) Inventor Morishita ▲ Introduction ▼ 1-280, Higashi Koigakubo, Kokubunji, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd.

Claims (2)

[Claims] 1. An acrylamide-based water-soluble polymer aqueous solution obtained by adding hydrochloric acid and thiourea to an acrylamide-based water-soluble polymer aqueous solution. 2. The acrylamide-based water-soluble polymer aqueous solution according to claim 1, wherein the acrylamide-based water-soluble polymer is an acrylamide-diacetone acrylamide-based water-soluble polymer.