Photosensitive alkali-soluble resin, method of preparing the same, and color photosensitive resist containing the same

1. A photosensitive alkali-soluble resin comprising a compound of formula (I):

wherein

n1 is an integer selected from the group consisting of 30 to 200;

n2 is an integer selected from the group consisting of 1 to 8;

R1 selected from the group consisting of —H, —O(CH 2 ) n3 OH, —O(CH 2 ) n4 OCOCH═CH 2 , —N(CH 3 ) 2 , —C n H 2n+1 and —SCH 3 ;

n3 is an integer selected from the group consisting of 1 to 6;

n4 is an integer selected from the group consisting of 1 to 5;

n is an integer selected from the group consisting of 1 to 12;

R2 is selected from the group consisting of —H and —CH 3 ; and

R3 is selected from the group consisting of —H and —CH 3 .

2. The photosensitive alkali-soluble resin of claim 1 , wherein

R1 is selected from the group consisting of —H, —O(CH 2 )2OH, —O(CH2) 2 OCOCH═CH 2 , —N(CH 3 ) 2 , —C 12 H 25 and —SCH 3 .

3. A method of preparing a photosensitive alkali-soluble resin comprising:

a) copolymerizing ethylene oxide with α-hydroxyalkyl phenyl ketone to obtain a first intermediate product;

b) copolymerizing the first intermediate product with a copolymerization product of glycerin acrylate, styrene and maleic anhydride to obtain the second intermediate product; and

c) oxidizing the second intermediate product to produce the photosensitive alkali-soluble resin, wherein the molar ratio of the ethylene oxide to the α-hydroxyalkyl phenyl ketone is 1:1 to 8:1; the molar ratio of the glycerin acrylate, the styrene and the maleic anhydride is (1-1.2):(1-1.2):(1-1.3); and molar ratio of the ethylene oxide to the glycerin acrylate is (0.5-6.1):1.

4. The method of claim 3 , wherein 3-mercapto propionic acid is used in the copolymerization of the ethylene oxide and the α-hydroxyalkyl phenyl ketone with a molar ratio of 3-mercapto propionic acid to ethylene oxide of (0-0.1):1; and a mercapto-based chain transfer agent is used in the copolymerization of glycerin acrylate, styrene and maleic anhydride with a molar ratio of mercapto-based chain transfer agent to the glycerin acrylate of (0-0.4):1.

5. The method of claim 4 , wherein the α-hydroxyalkyl phenyl ketone is selected from the group consisting of HMPP and HHMP.

6. The method of claim 4 , wherein a) is carried out at a temperature of 70 to 120° C.; and b) is carried out at a temperature of 70 to 100° C.

7. The method of claim 4 , wherein, in c), the oxidization is carried out by adding a material selected from the group consisting of K 2 FeO 4 , dimethyl sulfoxide and dicyclohexylcarbodiimide.

8. The method of claim 4 , wherein the copolymerization of both a) and b) is carried out in a solvent selected from the group consisting of di(propylene glycol) methyl ether acetate and ethyl 3-ethoxypropionate.

9. The method of claim 4 , wherein the products obtained after the copolymerization of both a) and b) are settled in a solvent selected from the group consisting of petroleum ether, toluene and cyclohexane.

10. The method of claim 4 , wherein the mercapto-based chain transfer agent selected from the group consisting of dodecyl thiol and mercapto ethanol.

11. A color photosensitive resist comprising the photosensitive alkali-soluble resin of claim 1 .