Method for manufacturing liquid crystal display panels

Abstract

A method for manufacturing an LCD panel comprises: (a) continuously feeding an LC cell comprising first and second substrates, the first substrate being relatively less susceptible to electrostatic decay than the second substrate, (b) laminating a first polarizing plate to the first substrate of the LC cell while avoiding direct contact between the first laminating member and the first substrate; (c) laminating a second polarizing plate to the second substrate with the first substrate being in contact with a second laminating member through the first polarizing plate laminated to the first substrate in the step (b) while avoiding direct contact between the second laminating member and the first substrate, thereby obtaining an LCD panel, and (d) conducting an inspection of the LCD panel without applying voltage, wherein steps (a), (b), (c) and (d) are performed sequentially in a single continuous feed line.

What is claimed is: 
     
         1 . A method for continuously manufacturing a liquid crystal display panel, comprising:
 (a) feeding a liquid crystal cell in a continuous feed line, the liquid crystal cell comprising first and second substrates having different relative susceptibility to electrostatic decay from each other, the first substrate being relatively less susceptible to electrostatic decay and the second substrate being relatively more susceptible to electrostatic decay;   (b) laminating a first polarizing plate to the first substrate of the liquid crystal cell with a first laminating member adapted to press the first polarizing plate to the first substrate in a manner that a direct contact between the first laminating member and the first substrate can be avoided, the first polarizing plate being provided from a first polarizing plate roll; then   (c) laminating a second polarizing plate to the second substrate of the liquid crystal cell with the first substrate being in contact with a second laminating member through the first polarizing plate laminated to the first substrate in the step (b) so that a direct contact between the second laminating member and the first substrate can be avoided, the second polarizing plate being laminated to the second substrate of the liquid crystal cell with a third laminating member adapted to press the second polarizing plate to the second substrate, the second laminating member being provided opposite to and in cooperative relation with the third laminating member, the second polarizing plate being provided from a second polarizing plate roll, thereby obtaining a liquid crystal display panel, and   (d) conducting an inspection of the liquid crystal display panel without applying voltage to the liquid crystal display panel,   wherein the steps (a), (b), (c) and (d) are performed in a single continuous feed line for feeding the liquid crystal cell and the liquid crystal display panel.   
     
     
         2 . The method according to  claim 1 , wherein the step (d) is performed at a position where electrostatic has discharged sufficiently for the inspection from the first and second substrates in the continuous feed line. 
     
     
         3 . The method according to  claim 1 , wherein the first substrate and the second substrate are determined based on the relative susceptibility to electrostatic decay of each of the substrates, the first substrate being relatively less susceptible to electrostatic decay and the second substrate being relatively more susceptible to electrostatic decay. 
     
     
         4 . The method according to  claim 1 , wherein the step (b) comprises bonding the first polarizing plate to the first substrate of the liquid crystal cell while feeding the liquid crystal cell from a feed-in side to a feed-out side along the feed line, and
 the step (c) comprises bonding the second polarizing plate to the second substrate of the liquid crystal cell while feeding the liquid crystal cell from a feed-in side to a feed-out side along the feed line.   
     
     
         5 . The method according to  claim 1 , wherein the step (d) comprises inspecting, in a line mode, the liquid crystal display panel formed by the step (b) and the step (c), while feeding the liquid crystal display panel from the feed-in side to the feed-out side along the feed line. 
     
     
         6 . The method according to  claim 1 , wherein the step (d) comprises:
 irradiating light to one side of the liquid crystal display panel and   receiving, at another side of the liquid crystal display panel, the light transmitted through the liquid crystal display panel to be inspected.   
     
     
         7 . The method according to  claim 1 , wherein the first polarizing plate laminating step comprises catching, between a pair of first bonding rollers, the liquid crystal cell and the first polarizing plate to bond the first polarizing plate to the first substrate of the liquid crystal cell, and
 the second polarizing plate laminating step comprises catching, between a pair of second rollers, the liquid crystal cell with the first polarizing plate bonded thereto and the second polarizing plate to bond the second polarizing plate to the second substrate of the liquid crystal cell.   
     
     
         8 . The method according to  claim 1 , wherein the first polarizing plate has an electrically-conductive layer. 
     
     
         9 . The method according to  claim 8 , wherein the electrically-conductive layer has a surface resistance of 1.0×1012 Ω/square or less. 
     
     
         10 . The method according to  claim 1 , wherein the second polarizing plate has an electrically-conductive layer. 
     
     
         11 . The method according to  claim 10 , wherein the electrically-conductive layer has a surface resistance of 1.0×1012 Ω/square or less. 
     
     
         12 . The method according to  claim 1 , wherein the step (b) includes laminating the first polarizing plate to the first substrate without contact between the first substrate and any bonding roller, thereby inhibiting the first substrate from being electrostatically charged. 
     
     
         13 . A method for continuously manufacturing a liquid crystal display panel, comprising:
 (a) feeding a liquid crystal cell in a continuous feed line, the liquid crystal cell comprising first and second substrates having different relative susceptibility to electrostatic decay from each other;   (b) laminating a first polarizing plate to the first substrate of the liquid crystal cell with a first laminating member adapted to press the first polarizing plate to the first substrate in a manner that a direct contact between the first laminating member and the first substrate can be avoided, the first polarizing plate being provided from a first polarizing plate roll; and then   (c) laminating a second polarizing plate to the second substrate of the liquid crystal cell with the first substrate being in contact with a second laminating member through the first polarizing plate laminated to the first substrate in the step (b) so that a direct contact between the second laminating member and the first substrate can be avoided, the second polarizing plate being laminated to the second substrate of the liquid crystal cell with a third laminating member adapted to press the second polarizing plate to the second substrate, the second laminating member being provided opposite to and in cooperative relation with the third laminating member, the second polarizing plate being provided from a second polarizing plate roll, thereby obtaining a liquid crystal display panel, and   (d) conducting an inspection of the liquid crystal display panel without applying voltage to the liquid crystal panel,   wherein the first substrate and the second substrate are determined based on the relative susceptibility to electrostatic decay of each of the substrates.   
     
     
         14 . The method according to  claim 1 , wherein the step (d) is performed at a position where electrostatic has discharged sufficiently for the inspection from the first and second substrates in the continuous feed line.