Method for manufacture of color filter and liquid crystal display

• US 5,503,952 A
• Filed: 03/15/1995
• Issued: 04/02/1996
• Est. Priority Date: 03/22/1994
• Status: Expired due to Fees

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Shinto Paint Co. Ltd.
• Inventors: Kubo, Akira, Suzuki, Tameyuki, Okada, Yoshikatsu
• Primary Examiner(s): Rosasco, S.
• Application Number:
  US08/404,741
• Time in Patent Office: 384 Days
• Field of Search: 430/7, 430/311, 430/321
• US Class Current: 430/7
• CPC Class Codes: G02B 5/201 in the form of arrays

Abstract

A color filter having discrete color layers arrayed on a substrate and light screening coating films interlaced between the color layers and if desired seal part having no coating film thereon, with high precision is industrially advantageously manufactured by (a) forming a transparent electroconductive layer on a transparent substrate, (b) coating the transparent electroconductive layer with a positive photoresist composition to form a photoresist layer, (c) exposing the photoresist layer to light through a photomask and developing the light-exposed photoresist layer to form a circuit-form photoresist layer, (d) etching and eliminating the transparent electroconductive layer bared in the gaps between the circuit-form photoresist layer to obtain a substrate having thereon a circuit-form laminate, (e) exposing the laminate to light through a photomask and developing the light-exposed laminate to bare the transparent electroconductive layer discretely, (f) carrying out electrodeposition using a thermosetting or photosensitive resin material-containing electro-deposition bath to form colored layers on the discretely bared transparent electroconductive layers, (g) eliminating the photoresist layer remaining after the development of step (e) to obtain a substrate having discrete color layers, the gaps being bared substrate surface and bared transparent electroconductive layer, (h) coating the substrate with a light screening material-containing photosensitive resin composition to form a light screening resin layer, and (i) exposing the light screening resin layer to light from the back side and developing the substrate to eliminate the unexposed part of the light screening resin layer. The color filter is well prevented from leakage of light and clear in coloration and superior in optical properties. A liquid crystal display of high image quality is manufactured by the use of this color filter.

Claims

1. A method for manufacturing a color filter having discrete color layers and light screening coating films interlaced between the color layers, which comprises the steps of:

(a) forming a transparent electroconductive layer on a transparent substrate,

(b) coating the transparent electroconductive layer formed in step (a) with a positive photoresist composition to form a photoresist layer,

(c) exposing the photoresist layer formed in step

(b) to light through a photomask having a prescribed pattern, followed by development to eliminate the light-exposed portion of the photoresist layer, forming the photoresist layer into a circuit-form,

(d) subjecting the resulting substrate to etching to eliminate the transparent electroconductive layer bared in the gaps of the circuit-form photoresist layer formed in step (c), obtaining a substrate having thereon a circuit-form laminate consisting of the transparent electroconductive layer as an under layer and the photoresist layer as an over layer,

(e) subjecting the substrate formed in step (d) to light-exposure through a photomask having a prescribed pattern, followed by development to bare the transparent electroconductive layer constituting the under layer of the laminate discretely,

(f) subjecting the resulting substrate to electrodeposition using a thermosetting or photosensitive resin material-containing electrodeposition bath to form color layers on the transparent electroconductive layer discretely bared in step (e),

(g) eliminating the photoresist layer remaining after the development in step (e) to obtain a substrate having the discrete color layers, the gaps thereof being the bared substrate surface and the bared transparent electroconductive layer,

(h) coating whole surface of the substrate formed in step (g) with a light screening material-containing photosensitive resin composition to form a light screening resin layer, and

(i) exposing the light screening resin layer formed in step (h) to light emitted from the side opposite to the light screening resin layer-carrying surface of the substrate, followed by development to eliminate the unexposed portion of the light screening resin layer.

2. A method according to claim 1, wherein the photoresist layer remaining after the development of step (e) is subjected to a heat treatment and/or a light irradiation treatment.

3. A method according to claim 2, wherein the electrodeposition of step (f) is carried out by using a photosensitive resin material-containing electro-deposition bath.

4. A method according to claim 1, wherein the electrodeposition of step (f) is carried out by using a photosensitive resin material-containing electro-deposition bath.

5. A method according to claim 1, which comprises the following steps (e'"'"'), (g'"'"') and (h'"'"'):

(e'"'"') subjecting the substrate formed in step (d) to light-exposure through a photomask having a prescribed pattern, followed by development to bare the transparent electroconductive layer constituting the under layer of the laminate discretely, while leaving uneliminated the photoresist layer in a seal part,

(g'"'"') eliminating the photoresist layer remaining after the development of step (e'"'"') and, if necessary, the photoresist layer at a seal part to obtain a substrate having the discrete color layers, the gaps thereof being the bared substrate surface and the bared transparent electroconductive layer,

(h'"'"') coating whole surface of the substrate formed in step (g'"'"') excluding the seal part with a light screening material-containing photosensitive resin composition to form a light screening resin layer, in place of steps (e), (g) and (h) in claim 1, respectively, and additionally comprises the following step (j);

(j) eliminating the photoresist layer of the seal part, if leaving uneliminated in steps (g'"'"') and (i).

6. A method according to claim 5, wherein the photoresist layer remaining after the development of step (e'"'"') is subjected to a heat treatment and/or a light irradiation treatment.

7. A method according to claim 6, wherein the electrodeposition of step (f) is carried out by the use of a photosensitive resin material-containing electro-deposition bath.

8. A method according to claim 5, wherein the electrodeposition of step (f) is carried out by the use of a photosensitive resin material-containing electro-deposition bath.

9. A method for manufacturing a liquid crystal display which comprises using the color filter manufactured according to the method of claim 5.

10. A method for manufacturing a liquid crystal display which comprises using the color filter manufactured according to the method of claim 1.