Liquid crystal display device
View Patent ↗In the step of curing a resin for bonding a TFT substrate and a counter substrate each having an alignment film that has been optically aligned by using UV-light, damage to the alignment film due to the UV-light can be prevented without using a light shielding mask. A UV-light absorption layer is formed between each black matrix on the counter substrate. The TFT and the counter substrates are sealed at their periphery by a resin that is cured by UV-light radiated from the counter substrate side. Since the absorption layer has a high absorbability to UV-light at a wavelength of 300 nm or less that degrades the alignment film, damage to the alignment film due to the UV-light for curing the resin can be prevented. Thus, provision of a light shielding mask for shielding the UV-light for the display region can be saved.
1. A liquid crystal display device comprising:
a TFT substrate having a first alignment film;
a counter substrate having a second alignment film and a light shielding film, the counter substrate being bonded to the TFT substrate by means of a seal material; and
liquid crystals sealed inside the substrates and the seal material;
wherein the counter substrate having a UV-light absorption layer formed between each light shielding film,
wherein the second alignment film is optically aligned by UV-light,
the second alignment film is formed between the light shielding film and the liquid crystals, and between the UV-light absorption layer and the liquid crystals,
the seal material is a UV-light curable resin,
the transmittance of the UV-light absorption layer to UV-light at a wavelength of 300 nm is lower than that to UV-light at a wavelength of 340 nm.
2. The liquid crystal display device according to claim 1 ,
wherein an overcoat layer being formed between the UV-light absorption layer and the second alignment layer,
the transmittance of the UV-light absorption layer to UV-light at a wavelength of 300 nm is lower than that of the overcoat film, and the transmittance of the UV-light absorption layer to UV-light at a wavelength of 340 nm is higher than that of the overcoat film.
3. The liquid crystal display device according to claim 2 ,
wherein the TFT substrate having an organic passivation film formed between the TFT substrate and the first alignment film,
the first alignment film is optically aligned by UV-light,
the transmittance of the UV-light absorption layer to UV-light at a wavelength of 300 nm is lower than that of the organic passivation film, and
the transmittance of the UV-light absorption layer to UV-light at a wavelength of 340 nm is higher than that of the organic passivation film.
4. The liquid crystal display device according to claim 3 ,
wherein the seal material is a UV-curable resin that is cured by UV-light at a wavelength of 340 nm or more; and
the alignment film is optically aligned by UV-light at a wavelength of 300 nm or less.
5. The liquid crystal display device according to claim 4 ,
wherein the liquid crystal display device is a monochromatic liquid crystal display device.
6. The liquid crystal display device according to claim 4 ,
wherein a color filter is formed between the counter substrate and the overcoat layer.
7. The liquid crystal display device according to claim 1 ,
wherein the TFT substrate having an organic passivation film formed between the TFT substrate and the first alignment film,
the first alignment film is optically aligned by UV-light,
the transmittance of the UV-light absorption layer to UV-light at a wavelength of 300 nm is lower than that of the organic passivation film, and the transmittance of the UV-light absorption layer to UV-light at a wavelength of 340 nm is higher than that of the organic passivation film.
8. The liquid crystal display device according to claim 7 ,
wherein the liquid crystal display device is a monochromatic liquid crystal display device.
9. The liquid crystal display device according to claim 4 ,
wherein a color filter is formed between the counter substrate and the overcoat layer.
10. The liquid crystal display device according to claim 1 ,
wherein the seal material is a UV-curable resin that is cured by UV-light at a wavelength of 340 nm or more; and
the alignment film is optically aligned by UV-light at a wavelength of 300 nm or less.
11. The liquid crystal display device according to claim 1 ,
wherein the liquid crystal display device is a monochromatic liquid crystal display device.
12. The liquid crystal display device according to claim 1 ,
wherein a color filter is formed between the counter substrate and the overcoat layer.