JPS62177526A - Liquid crystal element - Google Patents

Abstract

PURPOSE:To prevent a pattern part from being positionally shifted by arranging the 3rd board having a color filter on the outside of the 1st substrate and setting up the sizes of the color filter and an electrode pattern part to lengths corresponding to the change of the sizes of the the 1st and 3rd substrates due to the difference between the thermal expansion coefficients of both the substrates. CONSTITUTION:A liquid crystal material is held between the 1st substrate 1 and the 2nd substrate forming an opposite electrode opposed to the electrode pattern part 3 on the 1st substrate 1 and the color filter is formed on the 3rd substrate 2 consisting of a material different from that of the 1st substrate 1 and arranged on the outside of the 1st substrate 1. The change of the sizes of respective boards at a heating time can be calculated from specific thermal expansion coefficient values for respective materials of the substrates. Namely, when the thermal expansion coefficient is alpha, a heating temperature is T, a room temperature is T1, and the size of the original material is l, the size l1 of the heated substrate is found out from l1=l+l{(T-T1)Xalpha}. Thereby, the deviation of the size due to the difference of the thermal expansion coefficient values at the heating time can be corrected by calculating the size of the unheated substrate from said quality on the basis of the previously set size. Consequently, the pattern part can be prevented from positional shift.

Description

[Detailed description of the invention] Ru.

[Summary of Disclosure] The unspecified specification and drawings describe the dimensions of the pattern portion of a substrate provided with a thin film transistor array and the pattern portion of the color filter substrate based on the difference in coefficient of thermal expansion in a color liquid crystal display element that provides color display by providing a color filter. By setting the length to correspond to the dimensional change of the substrate, it is possible to prevent the positional shift of the pattern portion.

[Prior Art] and [Problems to be Solved by the Invention] Conventionally, in this type of display device, substrates made of the same material are used for both a thin film transistor (hereinafter referred to as TFT) substrate and a color filter substrate. Among these, G7059 glass plate, blue plate glass substrate, etc. are used as the glass substrate.

The 17059 board is expensive and costs L.
For blue plate glass substrate, α-9 formed on TPT substrate 1
There was a drawback that the i-film deteriorated due to the alkaline components in the blue plate glass. In order to solve this drawback, a method has been proposed in which a 17059 glass substrate is used as the TPT substrate and a thick plate glass substrate is used as the color filter substrate. However, at the stage of cell assembly, the sealing compound is heated to the curing temperature (approximately 170°C) to solidify, which has the disadvantage that the display pattern may be misaligned due to the difference in coefficient of thermal expansion. .

Yoshiko The present invention was made in order to solve the drawbacks of the conventional 1-screen method, and provides a color liquid crystal display element that prevents misalignment of pattern parts when TFT l plates and color filter substrates made of different materials are bonded together. The purpose is to provide the following.

[L stage for solving the problem] Means for solving the above problem will be explained using FIG. 1 corresponding to the embodiment. A liquid crystal material is sandwiched between the electrode pattern portion 3 on the substrate 1 and a second substrate provided with a counter electrode facing the electrode pattern portion 3 on the substrate 1.
On the outside of the substrate l, a third substrate made of a material different from that of the first substrate l.
A color filter is provided on the #1 first substrate 1.
This is a liquid crystal display device characterized in that the length of the pattern portions (3 and 4) of the substrate 2 provided with the color filter and the color filter is made to correspond to the dimensional change of the substrate due to the difference in the coefficient of thermal expansion.

[Function] The change in dimensions of each substrate upon heating can be calculated from the coefficient of thermal expansion specific to the material of the substrate. That is, assuming that the coefficient of thermal expansion is α, the heating temperature is T, the room temperature is TI, and the dimensions of the raw material are Mata, the dimension statement 1 after heating is: ! 11 = 10 sentences ((T-TI)Xα) ・・・・・・(
It can be found from 1). Therefore, by calculating the dimensions before heating from the above equation (1) using the preset dimensions as a reference, it is possible to correct the deviation in dimensions due to the difference in the coefficient of thermal expansion during heating.

[Example] An example of the present invention will be described with reference to FIG. In Figure 1, 1 is a TFT substrate (17059 glass) and 2 is a color filter substrate (blue plate glass).

Placed on a TPT substrate. Reference numeral 3 indicates a filter pattern portion of the color filter substrate 2, and reference numeral 4 indicates a TFT substrate type polar pattern portion. Further, 5 is a sealant for bonding the FT substrate 1 and the color filter substrate 2 together.

First, the dimensional change due to the difference in the coefficient of thermal expansion of the two substrates is
This will be explained using a specific example.

The dimensions of the electrode pattern section 4 of the TFT substrate 1 and the filter pattern section 3 of the color filter substrate 2 are 53.0 mm in length and 74.8 mm in width, and a sealant 5 is applied between the substrates. Curing temperature of 170℃
When heated up to
℃, formula (1) TPT board board side control turf part (45XIQ-'X(170-23))53.0+
53.0=53.0351txtm horizontal (45X10-'
X(+7O-23))? 4.8+74.6=74.84
93mm color filter board side pattern part: Vertical (92X10-'X(+7O-23))53.0+
53.0≧53.0717mm horizontal (92XIO'X(1
70-23)) 74.8+74-6=74.7009m
m. That is, the pattern portion on the color filter substrate side is larger than the pattern portion on the TFT & board side.

Next, a case will be described in which dimensions are determined in advance by considering the expansion coefficient in order to eliminate misalignment of the pattern portion due to such a difference in expansion coefficient.

The vertical dimension of the pattern section on the TFT substrate side is A, the horizontal dimension is B, the vertical dimension of the pattern section on the color filter side is C1, and the horizontal dimension is D. In addition, the dimensions of each pattern portion obtained after heating to 170°C are 53.0 l in length and 74.0 l in width. f3
If tg+, the dimensions of each pattern part before heating are A, B,
C and D are as follows: TPT board side: Vertical (45X10-I X147) XA+A=53.0 Horizontal (45X10-I X147) 53.
0 horizontal (92x10x147)XD+D=74.8. Therefore, when heating is performed at 170° C. at a room temperature of 23° C., misalignment of the pattern portions can be prevented by setting each pattern dimension to the above numerical values.

Note that in the cooling process after heating to 170° C., there is no dimensional change due to hardening of the sealant. Furthermore, the liquid crystal element of the present invention can use twisted nematic liquid crystal or ferroelectric liquid crystal as the liquid crystal.

[Effects of the Invention] As explained above, according to the present invention, even if the substrates are made of different materials, by setting the pattern dimensions in advance by considering the coefficient of thermal expansion of each substrate, it is possible to prevent misalignment of the pattern portion. It can be prevented. Furthermore, since an inexpensive substrate can be used, costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a 47-plane view of a substrate showing an embodiment of the present invention. l...TPT substrate, 2...color filter substrate,
3... Electrode pattern section, 4... Filter pattern section.

Claims (1)

[Claims] 1) In a liquid crystal element in which a liquid crystal material is sandwiched between a first substrate and a second substrate provided with a counter electrode opposite to the electrode pattern on the first substrate, a color is provided on the outside of the first substrate. A third substrate provided with a filter is provided, and the dimensions of the color filter and electrode pattern portion are set to lengths corresponding to changes in dimensions of the substrate due to the difference in coefficient of thermal expansion between the first substrate and the third substrate. A liquid crystal element.