Black matrix, method for the preparation thereof, flat display device and electromagnetic interference filter employing the same
View Patent ↗A novel black matrix, a method for preparing the same, and a flat display device and an electromagnetic interference filter to which the black matrix is applied. The black matrix is prepared by exposing a photoactive compound to form a latent pattern of nuclei for crystal growth and treating the latent pattern of nuclei for crystal growth with a metal salt solution to give a metal particle-deposited pattern; forming an electroless Ni-plated layer on the metal particle-deposited pattern; and forming an electroless Cu-plated layer on the electroless Ni-plated layer. Exhibiting improved black tone, which is achieved only by a selective multilayer plating process, without using expensive vacuum sputtering apparatus or a photolithographic process, the black matrix can be applied to various flat display devices. In addition, due to improved electric conductivity, the black matrix can be used in an electromagnetic interference filter, without employing an additional front surface blackening process.
1. A black matrix, comprising:
(i) a substrate;
(ii) a photosensitive film in direct contact with the substrate;
(iii) a Ni-plated layer positioned on the photosensitive film; and
(iv) a Cu-plated layer positioned on the Ni-plated layer.
2. The black matrix as defined in claim 1 , wherein the photosensitive film is a TiO 2 layer.
3. The black matrix as defined in claim 1 , wherein the Ni-plated layer is an electroless Ni-plated layer.
4. The black matrix as set forth in claim 1 , wherein the Cu-plated layer comprises an electroless Cu-plated layer and a Cu-electroplated layer.
5. An electromagnetic interference filter, comprising the black matrix of claim 1 .
6. A flat display device, comprising the black matrix of claim 1 .
7. A black matrix as defined in claim 1 , wherein the photosensitive film includes an Ti-containing organic metal compound.
8. A black matrix as defined in claim 1 , further comprising:
a metal particle-deposited pattern interposed between the photosensitive film and the Ni-plated layer and operative to promote crystal growth of the Ni-plated layer.
9. A method for preparing a black matrix, comprising:
(i) exposing a photoactive compound to form a latent pattern of nuclei for crystal growth and treating the latent pattern of nuclei for crystal growth with a metal salt solution to give a metal particle-deposited pattern;
(ii) forming an electroless Ni-plated layer on the metal particle-deposited pattern; and
(iii) forming an electroless Cu-plated layer on the electroless Ni-plated layer.
10. The method as defined in claim 9 , wherein the step (i) comprises (a) applying the photoactive compound onto a substrate to form a photosensitive film; (b) applying a water-soluble polymer onto the photosensitive film to form a water-soluble polymer layer; (c) selectively exposing the water-soluble polymer layer to light to give a latent pattern of nuclei for crystal growth; and (d) treating the latent pattern of nuclei for crystal growth with a metal salt solution to afford a metal salt particle-deposited pattern.
11. The method as defined in claim 10 , further comprising forming a Cu-electroplated layer on the electroless Cu-plated layer formed in the step (iii).
12. The method as defined in claim 10 , further comprising treating the electroless Ni-plated layer with a metal salt solution to give a metal particle-deposited pattern before the formation of the electroless Cu-plated layer in step (iii).
13. The method as defined in claim 10 , wherein the photoactive compound of step (i) is an organic metal compound containing Ti.
14. The method as defined in claim 10 , further comprising adding a photo-accelerator to the water-soluble polymer before the formation of the water-soluble polymer layer in step (b).
15. The method as defined in claim 14 , wherein the photo-accelerator is used in an amount from 0.01 to 5 weight parts per 100 weights parts of the water-soluble polymer.
16. The method as defined in claim 14 , wherein the water-soluble polymer is selected from a group consisting of homopolymers and copolymers of polyvinyl alcohol, polyvinyl phenol, polyvinyl pyrrolidone, polyacrylic acid, polyacrylic amide and gelatine.
17. The method as defined in claim 14 , wherein the photo-accelerator is selected from a group consisting of water-soluble dye, water-soluble organic acids, water-soluble organic acid salts, and water-soluble organic amines.
18. The method as defined in claim 17 , wherein the photo-accelerator is selected from a group consisting of tar dye, potassium or sodium salts of chlorophylline, riboflavine or its derivatives, annatto, CuSO 4 , caramel, curcumine, cochinal, citric acid, ammonium citrate, sodium citrate, oxalic acid, potassium tartrate, sodium tartrate, ascorbic acid, formic acid, triethanolamine, monoethanolamine, and malic acid.
19. The method as defined in claim 10 , wherein the metal salt solution is selected from a group consisting of an Ag salt solution, a Pd salt solution and mixtures thereof.
20. The method as defined in claim 9 , further comprising forming a Cu-electroplated layer on the electroless Cu-plated layer formed in the step (iii).
21. The method as defined in claim 9 , further comprising treating the electroless Ni-plated layer with a metal salt solution to give a metal particle-deposited pattern before the formation of the electroless Cu-plated layer in step (iii).
22. The.method as defined in claim 9 , wherein the photoactive compound of step (i) is an organic metal compound containing Ti.
23. The method as defined in claim 22 , wherein the organic metal compound containing Ti is selected from a group consisting of tetraisopropyltitanate, tetra-n-butyl titanate, tetrakis(2-ethyl-hexyl)titanate and polybutyltitanate.
24. The method as defined in claim 9 , wherein the metal salt solution is selected from a group consisting of an Ag salt solution, a Pd salt solution and mixtures thereof.