TWI630450B - Liquid crystal display device and radiation-sensitive resin composition - Google Patents

Abstract

The present invention provides a liquid crystal display element which reduces the influence of a contact hole and improves brightness, and a radiation sensitive resin composition used in the production thereof. The liquid crystal display element is formed by sandwiching a liquid crystal between a TFT substrate and a counter substrate. The TFT substrate includes a first insulating film formed of a first radiation sensitive resin composition, a contact hole, a first electrode connected to a source of the TFT via a contact hole, and a second sense by filling the contact hole. A second insulating film formed by irradiating a linear resin composition. A second electrode connected to the first electrode is disposed on the second insulating film. The third electrode is provided on the first electrode and the second electrode via the third insulating film. The liquid crystal display element applies a voltage between the first electrode and the second electrode and the third electrode to drive the liquid crystal.

Description

Liquid crystal display element and radiation sensitive resin composition

The present invention relates to a liquid crystal display element and a radiation sensitive resin composition.

The liquid crystal display element has a structure in which liquid crystal is sandwiched between a pair of substrates. An electrode may be provided on these substrates, and an alignment film may be provided on the surface of the substrate for the purpose of controlling the alignment of the liquid crystal. Moreover, these pair of substrates are sandwiched by, for example, a pair of polarizing plates. Further, when an electric field is applied between the substrates, the liquid crystal is driven to cause alignment change, and the light is partially transmitted and blocked. In the liquid crystal display element, an image is displayed using such characteristics. This liquid crystal display element has an advantage of being thinner or lighter than a conventional cathode ray tube (CRT) type display device.

The liquid crystal display element which was originally developed was used as a display element of a calculator or a timepiece centered on a character display or the like. Thereafter, the dot matrix display is facilitated by the development of a simple matrix method, thereby expanding the use to a display element of a note personal computer or the like. Secondly, through the thin film transistor (Thin Film) that is useful for switching in each pixel configuration The development of the active matrix method of Transister; TFT) has achieved good image quality with excellent contrast ratio or response performance. In addition, the liquid crystal display device has been overcome the problems of high definition, colorization, and viewing angle expansion, and has been used in displays for desktop computers and the like. Recently, a wider viewing angle, higher-speed response of liquid crystals, and improved display quality have been realized, and it has begun to be used as a display device for a large-sized and thin television display element or a portable electronic device such as a smart phone that requires high-density display.

Among the liquid crystal display elements, various liquid crystal modes in which the initial alignment state or the alignment change operation of the liquid crystal is different are known. For example, there are Twisted Nematic (TN), Super Twisted Nematic (STN), In-Planes Switching (IPS) (Fringe Field Switching (FFS)), vertical Liquid crystal mode such as Vertical Alignment (VA) or Optically Compensated Birefringence (OCB).

In the liquid crystal mode, the IPS mode and the VA mode have a wide viewing angle, a fast response speed, and a high contrast ratio, and thus are a liquid crystal mode that has been particularly attracted in recent years. In addition, the IPS mode in the present specification is a liquid crystal mode in which the liquid crystal is switched (alignment change) in the plane of the substrate sandwiched by the liquid crystal, as will be described later, except for the so-called transverse electric field method. Also included is an FFS mode that uses a tilted electric field (edge electric field) to switch the liquid crystal.

For example, in a liquid crystal display device including an IPS mode of the FFS mode (hereinafter simply referred to as "IPS mode"), the initial alignment of the liquid crystal is controlled such that the liquid crystal sandwiched between the pair of substrates is substantially parallel with respect to the substrate. status. Pass on A voltage is applied between the pixel electrode disposed on one of the substrates and the common electrode to form an electric field mainly composed of a component parallel to the plane of the substrate (so-called transverse electric field or oblique electric field (fringe field)), alignment of the liquid crystal State changes. Therefore, in the IPS mode, the alignment change of the liquid crystal due to the application of the electric field is mainly the rotation operation of the liquid crystal molecules in the plane parallel to the plane of the substrate as indicated by the name.

For this reason, the IPS mode differs from the TN mode (the parallel alignment of the liquid crystal in the TN mode by the application of an electric field), and the change in the tilt angle of the liquid crystal with respect to the substrate sandwiching the liquid crystal is small. Therefore, in the liquid crystal display device of the IPS mode, the change in the effective value accompanying the delay of the applied voltage is small, and the viewing angle is widened, so that a high-quality image can be displayed.

Development of a structure in which an inorganic insulating film containing an inorganic material is sandwiched between a transparent full-surface electrode (for example, a common electrode or a pixel electrode) in a liquid crystal display device of the IPS mode as described above. The structure of the electrode (for example, a pixel electrode or a common electrode) of the slit-shaped notch portion (for example, see Patent Document 1, Patent Document 2, or Patent Document 3). With this electrode structure, the aperture ratio of the pixel is improved, and high-intensity image display is realized.

Further, in the IPS mode liquid crystal display device, in recent years, in order to cope with a display of a portable electronic device such as a television that displays an animation or a smart phone that requires high-density display, further high image quality, particularly high definition, is required.

In the IPS mode liquid crystal display device, an active element such as a TFT for switching is disposed on one of a pair of substrates sandwiching the liquid crystal. Further, a pixel electrode, a common electrode, and a wiring connected to these electrodes are disposed to constitute a TFT. Substrate. Therefore, in the liquid crystal display device of the IPS mode, the number of constituent members disposed on the TFT substrate is increased, and the arrangement of the electrode structure or the wiring on the TFT substrate is complicated as compared with other liquid crystal modes such as the TN mode. For this reason, if further high definition is desired, the area of the pixel electrode in the pixel is reduced, and the aperture ratio of the pixel is lowered, so that there is a suspense in which the display luminance is lowered.

Patent Document 2 discloses a TFT substrate in which a pixel electrode having a slit-like notch portion is disposed on a entire surface of a common electrode via an interlayer insulating film containing an inorganic material. Further, Patent Document 3 also discloses a TFT substrate in which a common electrode having a slit-like notch portion is disposed on a planar pixel electrode via an inorganic interlayer insulating film. Further, Patent Literature 2 and Patent Document 3 disclose that an insulating film containing an organic material is provided between the entire planar common electrode or the entire planar pixel electrode and the wiring existing under the layer (hereinafter also referred to as "organic Insulation film") technology. Therefore, it is expected to suppress an increase in the coupling capacitance between the pixel electrode and the wiring, and to improve the aperture ratio.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2011-48394

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2011-59314

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2012-226249

However, in the technique of providing an organic insulating film on the TFT substrate, it is necessary to provide a contact hole in order to electrically connect the pixel electrode to the source of the TFT. The pixel electrode uses a so-called transparent electrode having high visible light transmittance, and usually includes a transparent conductive material such as tin-doped indium tin oxide (ITO). Further, as described in Patent Document 3, in order to prevent disconnection of the pixel electrode, it is preferable to set the taper angle of the contact hole to 45 degrees or less. The organic insulating film has a thickness of about several μm, and the contact hole on the TFT substrate has a large area in plan view.

In the liquid crystal display element, uniform initial alignment of the liquid crystal when no voltage is applied can be achieved by the alignment film provided on the surface of the substrate sandwiching the liquid crystal. For example, the alignment film can be subjected to a rubbing treatment such as rubbing treatment or a photoalignment treatment by irradiation of polarized light or the like to realize initial alignment of the liquid crystal.

In this case, the portion where the contact hole is formed on the substrate is recessed compared with the other portions, and it becomes a portion where the rubbing treatment or the photo-alignment treatment is difficult. Therefore, the portion where the contact hole of the TFT substrate is formed is a portion where the alignment of the liquid crystal which causes light leakage is likely to occur.

Further, in the liquid crystal display device of the IPS mode, the contact hole is a recess formed on the TFT substrate as described above, and the formed portion is a portion where the thickness of the liquid crystal is thicker than other portions. Therefore, the portion where the contact hole is formed is a portion in which the transmittance or the response characteristic of the liquid crystal is different from that of the other portions, and the portion where the uniformity of image display is lowered is caused.

For this reason, it has been studied to provide a light-shielding shading for a portion of a pixel that is affected by the formation of a contact hole in the liquid crystal display element of the IPS mode. The mechanism that does not use it to display images. However, the arrangement of such a light-shielding mechanism causes the aperture ratio of the pixel to decrease, and the transmittance of the liquid crystal display element is lowered. In other words, in the liquid crystal display device of the IPS mode, the contact hole is a factor that hinders the improvement of the luminance characteristics, and the further display is prevented from being high-definition.

Therefore, in the liquid crystal display device of the IPS mode, it is required to reduce the influence of the contact hole provided on the TFT substrate, improve the luminance characteristics, and perform a technique of further high-definition display.

Further, as described in Patent Document 3, in the VA mode liquid crystal display device, a technique of providing an organic insulating film between the pixel electrode and the wiring located under the layer to improve the aperture ratio has been studied. Therefore, in the VA mode liquid crystal display device having such a configuration, it is also required to form a contact hole on the TFT substrate in the same manner as the IPS mode liquid crystal display element. Therefore, in the VA mode liquid crystal display device, it is also required to reduce the influence of the contact hole provided on the TFT substrate, improve the luminance characteristics, and perform further high-definition display.

Further, in the liquid crystal display device of another mode, an organic insulating film may be provided between the pixel electrode and the wiring under the layer in the same manner as the IPS mode liquid crystal display device having the above-described configuration, so that the aperture ratio is improved. technology. Therefore, in the liquid crystal display device of another mode, in the same manner as described above, it is required to reduce the influence of the contact hole provided on the TFT substrate, to improve the luminance characteristics, and to perform further high-definition display.

The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a liquid crystal display element which can reduce the influence of a contact hole and improve the brightness.

Further, an object of the present invention is to provide a radiation-sensitive resin composition used for the production of a liquid crystal display element which has an effect of reducing contact holes and improving brightness.

Other objects and advantages of the present invention will become apparent from the following description.

According to a first aspect of the invention, a liquid crystal display device is a liquid crystal display device in which a liquid crystal is sandwiched between a first substrate and a second substrate that are disposed opposite to each other, wherein the first substrate includes a TFT and a first insulating layer. The film is provided on the TFT and the contact hole by using the first radiation-sensitive resin composition, and is formed on the first insulating film and the first electrode, and is provided on the first insulating film and the inner wall of the contact hole via the contact. The second insulating film is electrically connected to the TFT, and the second insulating film is provided by using the second radiation-sensitive resin composition so as to fill the contact hole, and the second electrode is provided on the second insulating film, and a part of the insulating film is provided on the second insulating film. The first electrode portion on the first insulating film is in contact with each other to be electrically connected to the first electrode, and the third electrode is provided on the first electrode and the second electrode of the first substrate via the third insulating film. Or the third electrode is provided on the liquid crystal side of the second substrate; and a voltage is applied between the first electrode and the second electrode and the third electrode to drive the liquid crystal The way it is composed.

In the first aspect of the present invention, it is preferable that the first radiation sensitive resin composition is a positive radiation sensitive resin composition, and the second radiation sensitive resin composition is a negative radiation sensitive resin composition, or The radiation sensitive linear resin composition is a negative radiation sensitive resin composition, and the second radiation sensitive resin composition is a positive radiation sensitive resin composition.

In the first aspect of the invention, it is preferable that the first radiation sensitive resin composition contains a polymer, and the polymer contains a constituent unit having a carboxyl group and a constituent unit having a polymerizable group.

In the first aspect of the invention, it is preferable that the second radiation-sensitive resin composition contains a polymer, and the polymer contains a constituent unit having a carboxyl group and a constituent unit having a polymerizable group.

A second aspect of the present invention is a radiation-sensitive resin composition which is a radiation-sensitive resin composition used for producing a liquid crystal display element in which a liquid crystal is sandwiched between a first substrate and a second substrate. The first substrate of the liquid crystal display device includes a TFT and a first insulating film, and is provided on the TFT and has a contact hole formed in the first insulating film and the first electrode, and is provided on the first insulating film and the contact hole. The inner wall is electrically connected to the TFT via the contact hole, and the second insulating film is provided to fill the contact hole, and The second electrode is provided on the second insulating film, and is partially connected to the first electrode portion on the first insulating film to be electrically connected to the first electrode, and the liquid crystal display device is a third electrode. The third electrode is provided on the first electrode and the second electrode of the first substrate, or the third electrode is provided on the liquid crystal side of the second substrate, and between the first electrode and the second electrode and the third electrode The liquid crystal is driven by applying a voltage, and the radiation sensitive resin composition is used to form a second insulating film of the first substrate.

The second aspect of the present invention preferably further contains metal oxide particles.

According to the first aspect of the present invention, it is possible to obtain a liquid crystal display element which reduces the influence of the contact hole and improves the luminance.

According to the second aspect of the present invention, it is possible to obtain a radiation-sensitive resin composition used for the production of a liquid crystal display element in which the influence of the contact hole is reduced and the luminance is improved.

1, 1-2, 100, 100-2‧‧‧ liquid crystal display elements

2, 102‧‧‧ TFT substrate

3, 103‧‧‧ opposite substrate

4, 104‧‧‧ LCD

5, 105‧‧‧TFT

6, 106‧‧‧1st insulating film

7, 107‧‧‧ contact holes

8, 108‧‧‧ first electrode

9, 9-2, 109, 109-2‧‧‧ second insulating film

10, 10-2, 110, 110-2‧‧‧ second electrode

11‧‧‧3rd insulating film

12, 112‧‧‧ third electrode

21, 121‧‧‧ gate insulating film

22, 122‧‧‧ inorganic passivation film

30, 130‧‧‧ signal line

31, 131‧‧‧ scan lines

32, 132‧‧‧ semiconductor layer

33, 133‧‧‧ drain

34, 134‧‧‧ source

40, 44, 140, 144‧‧ ‧ alignment film

41, 141‧‧‧ Black matrix

42, 142‧‧‧ color filters

43,143‧‧‧ flattening film

50‧‧‧ gap

FIG. 1 is a cross-sectional view showing a configuration of an IPS mode liquid crystal display element according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of an IPS mode liquid crystal display element according to the first embodiment of the present invention.

Fig. 3 is a view schematically showing an IPS mode liquid crystal according to a first embodiment of the present invention; A cross-sectional view showing the structure of another example of the display element.

FIG. 4 is a cross-sectional view showing a configuration of a VA mode liquid crystal display element according to a second embodiment of the present invention.

FIG. 5 is a plan view schematically showing a configuration of a VA mode liquid crystal display element according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a configuration of another example of a VA mode liquid crystal display element according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be appropriately described using the drawings.

Further, in the present invention, the "radiation" irradiated at the time of exposure includes visible light rays, ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams, and the like.

Embodiment 1.

<IPS mode liquid crystal display element>

FIG. 1 is a cross-sectional view showing a configuration of an IPS mode liquid crystal display element according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of an IPS mode liquid crystal display element according to the first embodiment of the present invention.

In addition, FIG. 1 schematically shows a cross section taken along line AA' of FIG. 2.

As shown in FIG. 1, the liquid crystal display element 1 of the IPS mode according to the first embodiment of the present invention is placed on the TFT substrate 2 as a first substrate which is disposed opposite to each other. The liquid crystal 4 is sandwiched between the counter substrate 3 of the second substrate. Here, the TFT substrate is a substrate having a TFT as a thin film transistor. As shown in FIG. 2, in the IPS mode liquid crystal display element 1, the TFT substrate 2 has a TFT 5.

That is, as shown in FIGS. 1 and 2, the TFT substrate 2 of the liquid crystal display element 1 includes a first insulating film 6 which is provided on the TFT 5 (not shown in FIG. 1), and a contact hole 7 which is formed in The first insulating film 6 is provided on the first insulating film 6 and on the inner wall of the contact hole 7, and is electrically connected to the source 34 of the TFT 5 via the contact hole 7; the second insulating film 9. It is provided so as to fill the contact hole 7, and the surface of the TFT substrate 2 is flattened.

The TFT substrate 2 has a second electrode 10 provided on the second insulating film 9.

In the TFT substrate 2, the second electrode 10 provided on the second insulating film 9 can be electrically connected to the first electrode 8 on the first insulating film 6 by the end portion as a part thereof.

Further, in the TFT substrate 2, the second electrode 10 provided on the second insulating film 9 may be connected so as to cover at least a part of the first electrode 8 on the first insulating film 6, thereby electrically Sexual connection.

In the liquid crystal display element 1 of the present embodiment, the first electrode 8 and the second electrode 10 electrically connected thereto are integrated to form a planar pixel electrode.

Further, the liquid crystal display element 1 has the third insulating film 11 on the first electrode 8 and the second electrode 10 of the TFT substrate 2, and further includes the third electrode 12 on the third insulating film 11. In other words, the liquid crystal display element 1 has a structure in which the third electrode 12 is provided on the first electrode 8 and the second electrode 10 of the TFT substrate 2 via the third insulating film 11. In the liquid crystal display element 1 of the present embodiment, the third electrode 12 constitutes a common electrode.

With the above configuration, the liquid crystal display element 1 applies a voltage between the first electrode 8 and the second electrode 10 on the TFT substrate 2 and the third electrode 12 on the TFT substrate 2 to drive the liquid crystal 4.

The liquid crystal display element 1 is an IPS mode liquid crystal display element.

Hereinafter, the configuration of the IPS mode liquid crystal display element 1 according to the first embodiment of the present invention will be described in more detail. First, the planar structure of the liquid crystal display element 1, in particular, the main planar structure of the pixel, will be mainly described using FIG.

In the liquid crystal display element 1, as shown in FIG. 2, a pixel surrounded by a signal line 30 extending in the longitudinal direction and a scanning line 31 extending in the lateral direction forms a pixel. A TFT 5 for switching is formed on the scanning line 31, and controls the supply of video signals to the first electrode 8 and the second electrode 10 constituting the pixel electrodes. As shown in FIG. 2, the scanning line 31 also serves as the gate of the TFT 5, and a semiconductor layer 32 made of amorphous germanium (a-Si) or microcrystalline germanium is formed on the scanning line 31.

A drain electrode 33 connected to the signal line 30 is formed on the semiconductor layer 32 so as to overlap the end portion, and the source electrode 34 is formed to face the drain electrode 33 with a gap interposed therebetween. The source electrode 34 extends in the formation region of the pixel, and is electrically connected to the first electrode 8 via the contact hole 7.

As shown in FIG. 2, the first electrode 8 indicated by a broken line is formed in a planar overall shape. Further, the second electrode 10 indicated by a broken line is formed in a planar shape so as to cover the contact hole 7 and to be in contact with the first electrode 8 at the end portion thereof. And, in these In the third insulating film 11 (not shown in FIG. 2), the third electrode 12 having the slit-shaped notch portion 50 which is an unformed portion of the electrode is provided.

In the liquid crystal display element 1 shown in FIG. 2, the first electrode 8 schematically indicated by a broken line extends from one end portion of the TFT 5 to cover the source electrode 34 in the pixel. The second electrode 10 schematically indicated by a broken line is also provided on the second insulating film 9 (not shown in FIG. 2) that fills the contact hole 7, and covers the source electrode 34. Further, the second electrode 10 covers the first electrode 8 via the second insulating film 9 as described above, and is electrically connected to the first electrode 8 at an end portion as a part thereof.

Further, the third electrode 12 having the slit-like notch portion 50 is not limited to one pixel, and may be shared with other pixels to form a common electrode, and a common voltage is applied. As shown in FIG. 1, the notch portion 50 formed on the third electrode 12 covers the source electrode 34 and the contact hole 7.

Next, the cross-sectional structure of the liquid crystal display element 1, in particular, the cross-sectional structure of the pixel, will be mainly described using FIG.

As shown in FIG. 1, the liquid crystal display element 1 has a gate insulating film 21 used in the TFT 5 of FIG. 2 formed on the TFT substrate 2, and a source electrode 34 extending from the TFT 5 is formed thereon. The source 34 of this portion can shield light from a backlight (not shown). The inorganic passivation film 22 is formed by covering the source electrode 34, and the first insulating film 6 which is also a planarizing film is formed thereon. The inorganic passivation film 22 is formed of, for example, a metal oxide such as SiO ₂ or a metal nitride such as SiN.

In the liquid crystal display element 1 of the present embodiment, the first insulating film 6 is formed by patterning using a first radiation sensitive resin composition to be described later. Organic insulating film. The first insulating film 6 is formed with a film thickness of, for example, 0.5 μm to 6 μm.

A contact hole 7 for electrically connecting the first electrode 8 and the source 34 is formed on the first insulating film 6. The contact hole 7 is formed by forming a through hole after forming the first insulating film 6. Thereafter, a through hole is also formed in the inorganic passivation film 22, and the through hole of the first insulating film 6 communicates with the through hole of the inorganic passivation film 22. As a result, a contact hole 7 penetrating the first insulating film 6 and the inorganic passivation film 22 is formed in the TFT substrate 2.

Further, in the example of the liquid crystal display element 1 shown in FIG. 1, the through holes of the first insulating film 6 and the through holes of the inorganic passivation film 22 can be formed using different masks. Further, as another method, after the through hole is formed in the first insulating film 6, the first insulating film 6 is used as a mask, and a through hole of the inorganic passivation film 22 is formed by dry etching, and the contact hole 7 is provided.

The contact hole 7 formed in the first insulating film 6 as described above includes a lower hole for connecting the first electrode 8 and the source 3, an upper hole having a larger diameter, and an inner wall connecting the lower hole and the upper hole. . In order to prevent disconnection of the first electrode 8 provided to cover the inner wall of the contact hole 7, it is preferable that the taper angle of the contact hole 7 is 45 degrees or less. Therefore, the contact hole 7 on the TFT substrate 2 becomes a large area in plan view.

Further, the first electrode 8 is provided on the first insulating film 6 and on the inner wall of the contact hole 7 so as to cover the first insulating film 6 and the contact hole 7. The first electrode 8 can be formed, for example, using ITO. In the liquid crystal display element 1, the first electrode 8 serving as a pixel electrode is formed in a planar entire surface. The first electrode 8 is electrically connected to the source 34 via the contact hole 7 .

Moreover, the liquid crystal display element 1 is provided in such a manner as to fill the contact hole 7 The second insulating film 9 is placed. The second insulating film 9 is an organic insulating film formed using a second radiation-sensitive resin composition to be described later. The second insulating film 9 of the liquid crystal display element 1 has a function of filling the contact holes 7 of the TFT substrate 2. Further, the second insulating film 9 functions to planarize the surface of the TFT substrate 2.

In addition, as a method of forming the second insulating film 9, for example, a light mask used for patterning of the first insulating film 6 can be formed to form the contact hole 7 and the like, and the second insulating film 9 can be formed by patterning.

In other words, the first insulating film 6 having the contact hole 7 is formed by using one type of light mask, and the first electrode 8 covering the same is provided, and then the mask is used again, and the second radiation-sensitive resin composition is used. The second insulating film 9.

In this case, for example, the first insulating film 6 in which the contact hole 7 is formed is formed by patterning by exposure and development through a photomask using a positive first radiation sensitive resin composition. Next, the first electrode 8 is formed. Thereafter, the second insulating film 9 which fills the contact hole 7 can be formed by using the negative-type second radiation-sensitive resin composition and performing the same exposure and development using the same light mask as described above.

The TFT substrate 2 of the liquid crystal display element 1 has the second electrode 10, and the second electrode 10 is provided on the second insulating film 9, and is electrically connected to the first electrode 8 on the first insulating film 6 by the end portion as a part thereof. Sexual connection. The second electrode 10 can be formed using the same material as the first electrode 8, and can be formed, for example, using ITO.

In the liquid crystal display element 1 of the present embodiment, the first electrode 8 and the second electrode 10 are electrically connected to each other and integrated, and can function as a planar pixel electrode.

In addition, the liquid crystal display element 1 has the third insulating film 11 serving as an interlayer insulating film on the first electrode 8 and the second electrode 10 of the TFT substrate 2. The third insulating film 11 can be, for example, an inorganic insulating film formed of a metal oxide such as SiO ₂ or a metal nitride such as SiN.

Further, the liquid crystal display element 1 has the third electrode 12 on the third insulating film 11, and the third electrode 12 has a slit-shaped notch portion 50 in which the electrode portion is not formed. The third electrode 12 and its notch portion 50 are formed on the upper layer of the contact hole 7 so as to cover the contact hole 7. The third electrode 12 can function as a common electrode in the liquid crystal display element 1.

An alignment film 40 for aligning the liquid crystal 4 is formed on the third electrode 12. The alignment film 40 can perform alignment processing by rubbing treatment to realize uniform alignment of the liquid crystal 4 when no voltage is applied, that is, parallel alignment parallel to the substrate surface of the TFT substrate 2.

The liquid crystal display element 1 has a counter substrate 3 as a second substrate sandwiching the liquid crystal 4. A black matrix 41 and a color filter 42 are formed on the counter substrate 3, and a flattening film 43 is formed to cover these, and an alignment film 44 is formed thereon. The alignment film 44 on the counter substrate 3 is the same as the alignment film 40 on the TFT substrate 2, and the alignment treatment by the rubbing treatment can be performed to realize the parallel alignment of the liquid crystal 4 as the initial alignment.

In the liquid crystal display element 1 of the present embodiment having the above configuration, a video signal is applied to the first electrode 8 and the second electrode 10 on the TFT substrate 2 in order to display an image, and voltage is applied between the third electrode 12 and the third electrode 12 , then around these A tilted electric field is generated. In other words, when a voltage is applied between the first electrode 8 and the second electrode 10 and the third electrode 12, a component having a component parallel to the substrate surface of the TFT substrate 2 is generated in the liquid crystal 4 via the notch portion 50 of the third electrode 12. Tilting electric field.

As a result, the liquid crystal 4 is driven by a component parallel to the substrate surface of the oblique electric field, and is rotated in a plane parallel to the substrate surface from the initial alignment state.

The liquid crystal display element 1 has a polarizing plate (not shown) on a surface on the counter liquid crystal side of the TFT substrate 2 and a surface on the counter liquid crystal side of the counter substrate 3, and the liquid crystal 4 is sandwiched between a pair of polarizing plates. Therefore, the liquid crystal display element 1 can partially transmit and block light by the rotation operation of the liquid crystal 4 caused by the oblique electric field, and can display an image using such characteristics.

Further, in the liquid crystal display element 1, the contact hole 7 provided in the TFT substrate 2 is filled with the second insulating film 9, and the surface of the TFT substrate 2 is flattened. Therefore, in the liquid crystal display element 1, the phenomenon in which the alignment of the liquid crystal 4 caused by the contact hole 7 is disordered, the transmittance due to the recess, and the response characteristic of the liquid crystal 4 are lowered are reduced. In other words, the liquid crystal display element 1 can reduce the influence of the contact hole 7 provided on the TFT substrate 2, and it is not necessary to form a large light shielding mechanism such as the source electrode 34, and the luminance characteristics can be improved.

In addition, the contact hole 7 of the liquid crystal display element 1 of the first embodiment of the present invention is filled with the second insulating film 9, and as shown in FIG. 1, the surface of the TFT substrate 2 is flattened. However, in the liquid crystal display element 1 of the present embodiment, the composition of the second radiation-sensitive resin composition forming the second insulating film 9 or the method of forming the second insulating film 9 may be formed in a plurality of depressions. 2 Upper surface of the insulating film 9 (surface on the liquid crystal 4 side).

FIG. 3 is a cross-sectional view showing a configuration of another example of the liquid crystal display element of the IPS mode according to the first embodiment of the present invention.

In addition, the IPS mode liquid crystal display element 1-2 which is another example of the first embodiment of the present invention shown in FIG. 3 has the same shape as that of FIG. 1 and the like except for the shape of the second insulating film 9-2. The liquid crystal display element 1 has the same structure. Therefore, the same constituent elements are denoted by the same reference numerals, and the overlapping description will be omitted.

In the IPS mode liquid crystal display element 1-2 which is another example of the first embodiment of the present invention, the upper surface of the second insulating film 9-2 on which the second electrode 10-2 is provided is recessed (liquid crystal 4) Side surface). In the liquid crystal display element 1-2, the contact hole 7 provided in the TFT substrate 2 is filled with the second insulating film 9-2, and the surface of the TFT substrate 2 is different from the case where the second insulating film 9-2 is not provided. It is flattened. Therefore, in the liquid crystal display element 1-2, the alignment disorder of the liquid crystal 4 caused by the contact hole 7 is reduced as compared with the case where the second insulating film 9-2 is not provided, and the transmittance due to the recess is alleviated. And the response characteristics of the liquid crystal 4 are lowered. In other words, the liquid crystal display element 1-2 can reduce the influence of the contact hole 7 provided on the TFT substrate 2, and it is not necessary to form a light shielding mechanism such as the source electrode 34, and the luminance characteristics can be improved.

Embodiment 2.

<VA mode liquid crystal display element>

FIG. 4 is a cross-sectional view showing a configuration of a VA mode liquid crystal display element according to a second embodiment of the present invention.

FIG. 5 is a plan view schematically showing a configuration of a VA mode liquid crystal display element according to a second embodiment of the present invention.

In addition, FIG. 4 schematically shows a cross section taken along line BB' of FIG.

As shown in FIG. 4, in the VA mode liquid crystal display device 100 of the second embodiment of the present invention, the liquid crystal 104 is sandwiched between the TFT substrate 102 as the first substrate and the counter substrate 103 as the second substrate. Composition. The liquid crystal 104 is a liquid crystal having a negative dielectric anisotropy (??).

Further, as shown in FIG. 5, in the VA mode liquid crystal display element 100, the TFT substrate 102 has a TFT 105.

That is, as shown in FIGS. 4 and 5, the TFT substrate 102 of the liquid crystal display element 100 includes the first insulating film 106, which is provided on the TFT 105 (not shown in FIG. 4), and the contact hole 107 is formed in the first The first electrode 108 is provided on the first insulating film 106 and on the inner wall of the contact hole 107, and is electrically connected to the source 134 of the TFT 105 via the contact hole 107. The second insulating film 109 is provided on the insulating film 106. The contact hole 107 is filled in such a manner as to planarize the surface of the TFT substrate 102.

Further, the TFT substrate 102 has the second electrode 110, and the second electrode 110 is provided on the second insulating film 109, and is electrically connected to the first electrode 108 on the first insulating film 106 by an end portion as a part thereof.

In the liquid crystal display device 100 of the present embodiment, the first electrode 108 and the second electrode 110 electrically connected thereto are integrated to form a pixel electrode.

Further, the liquid crystal display element 100 has the third electrode 112 on the liquid crystal 104 side of the counter substrate 103. In the liquid crystal display element 100 of the present embodiment, the third electrode 112 constitutes a common electrode.

As a result, the liquid crystal display element 100 is the first on the TFT substrate 102. The electrode 108 and the second electrode 110 are connected to the third electrode 112 on the counter substrate 103 to drive the liquid crystal 104. The liquid crystal display element 100 is configured to apply a voltage between the first electrode 108 and the second electrode 110 and the third electrode 112 on the counter substrate 103 to drive the liquid crystal 104 having a negative dielectric anisotropy. VA mode liquid crystal display element.

Hereinafter, the configuration of the VA mode liquid crystal display element 100 according to the second embodiment of the present invention will be described in more detail. First, the planar structure of the liquid crystal display element 100, particularly the main planar structure of the pixel, will be mainly described using FIG.

In the liquid crystal display element 100, as shown in FIG. 5, a pixel surrounded by a signal line 130 extending in the longitudinal direction and a scanning line 131 extending in the lateral direction forms a pixel. A TFT 105 for switching is formed on the scanning line 131, and controls the supply of video signals to the first electrode 108 and the second electrode 110 constituting the pixel electrodes. As shown in FIG. 5, the scanning line 131 also serves as the gate of the TFT 105, and a semiconductor layer 132 made of amorphous germanium (a-Si) or microcrystalline germanium is formed on the scanning line 131.

A drain electrode 133 connected to the signal line 130 is formed on the semiconductor layer 132 so as to overlap the end portion, and the source electrode 134 is formed to face the drain electrode 133 with a gap interposed therebetween. The source electrode 134 extends in the formation region of the pixel, and is electrically connected to the first electrode 108 via the contact hole 107.

As shown in FIG. 5, the first electrode 108 is formed in a planar shape. Further, the second electrode 110 is formed in a planar shape so as to cover the contact hole 107 and to be in contact with the first electrode 108 at the end portion thereof.

In addition, the first electrode 108 and the second electrode 110 are integrally formed as described above to form a pixel electrode, but in the example shown in FIG. 5, they are formed in a planar shape. In the liquid crystal display device 100, as another example, the first electrode 108 and the second electrode 110 may each have a slit-shaped notch portion in which an electrode portion is not formed. In this case, after the first electrode 108 and the second electrode 110 are formed as shown in FIG. 5, these are collectively patterned, and the notch portion can be provided in the first electrode 108 and the second electrode 110.

Since the first electrode 108 and the second electrode 110 have notch portions, the liquid crystal display element 100 can generate a voltage when a voltage is applied between the first electrode 108 and the second electrode 110 and the third electrode 112 on the counter substrate 103. The electric field perpendicular to the substrate surface and the electric field which becomes a plurality of inclinations can control the tilt direction of the liquid crystal 104.

In the liquid crystal display element 100 shown in FIG. 5, the first electrode 108 extends from one end of the TFT 105 and covers the source 134 in the pixel. The second electrode 110 is also provided on the second insulating film 109 (not shown in FIG. 5) that fills the contact hole 107 to cover the source electrode 134. Further, the second electrode 110 covers the first electrode 108 via the second insulating film 109 as described above, and is electrically connected to the first electrode 108 from the end portion as a part thereof.

Next, the cross-sectional structure of the liquid crystal display element 100, particularly the cross-sectional structure of the pixel, will be mainly described using FIG.

As shown in FIG. 4, the liquid crystal display element 100 has a gate insulating film 121 used in the TFT 105 of FIG. 5 formed on the TFT substrate 102, and a source electrode 134 extending from the TFT 105 is formed thereon. The source 134 of this portion can shield light from a backlight (not shown). The inorganic passivation film 122 is formed by covering the source electrode 134, and the first insulating film 106 which also serves as a planarization film is formed thereon. The inorganic passivation film 122 can be formed, for example, of a metal oxide such as SiO ₂ or a metal nitride such as SiN.

In the liquid crystal display device 100 of the present embodiment, the first insulating film 106 is an organic insulating film formed by patterning using a first radiation-sensitive resin composition to be described later. The first insulating film 106 can be formed, for example, at a film thickness of 0.5 μm to 6 μm.

A contact hole 107 for electrically connecting the first electrode 108 and the source 134 is formed on the first insulating film 106. The method of forming the contact hole 107 can be the same as the method of forming the contact hole 7 of the liquid crystal display element 1 of the first embodiment.

The contact hole 107 formed in the first insulating film 106 includes a lower hole for connecting the first electrode 108 and the source 103, an upper hole having a larger diameter, and an inner wall connecting the lower hole and the upper hole. In order to prevent disconnection of the first electrode 108 provided to cover the inner wall of the contact hole 107, it is preferable that the taper angle of the contact hole 107 is 45 degrees or less. Therefore, the contact hole 107 on the TFT substrate 102 has a large area in plan view.

Further, the first electrode 108 is provided on the first insulating film 106 and on the inner wall of the contact hole 107 so as to cover the first insulating film 106 and the contact hole 107. The first electrode 108 can be formed, for example, using ITO. In the liquid crystal display element 100, the first electrode 108 which becomes a pixel electrode is formed, for example, as a planar surface as described above. The first electrode 108 is electrically connected to the source 134 via the contact hole 107.

Further, the liquid crystal display element 100 has a second insulating film 109 provided to fill the contact holes 107. The second insulating film 109 is a second sensing layer to be described later. An organic insulating film formed by a radioactive resin composition. The second insulating film 109 of the liquid crystal display element 100 has a function of filling the contact hole 107 of the TFT substrate 102 and flattening the surface of the TFT substrate 102.

The method of forming the second insulating film 109 can be the same as the method of forming the second insulating film 9 of the liquid crystal display element 1 of the first embodiment.

Therefore, for example, in order to form the contact hole 107 or the like, the second insulating film 109 can be formed by patterning using a light mask used for patterning of the first insulating film 106.

In other words, the first insulating film 106 having the contact hole 107 can be formed by using one type of light mask, and after the first electrode 108 covering the surface is provided, the mask can be used again, and the second radiation-sensitive resin composition can be used. The second insulating film 109 is formed.

In this case, for example, a positive first radiation sensitive resin composition is used, and exposure through a photomask and patterning by development are performed to form a first insulating film 106 on which a contact hole 107 is formed. Next, the first electrode 108 is formed. Thereafter, the second insulating film 109 which fills the contact hole 107 can be formed by using the negative-type second radiation-sensitive resin composition and performing the same exposure and development using the same light mask as described above.

Further, the TFT substrate 102 of the liquid crystal display element 1 has the second electrode 110, and the second electrode 110 is provided on the second insulating film 109, and the first electrode on the first insulating film 106 is formed as an end portion thereof. 108 electrical connection. The second electrode 110 can be formed using the same material as the first electrode 109, and can be formed, for example, using ITO.

In the liquid crystal display element 100 of the present embodiment, the first electrode 108 and The second electrodes 110 are electrically connected to each other and can function as a pixel electrode.

An alignment film 140 for aligning the liquid crystal 104 is formed on the first electrode 108 and the second electrode 110. The alignment film 140 is a vertical alignment type alignment film. The alignment film 140 is subjected to an appropriate alignment treatment such as a rubbing treatment or a photo alignment treatment, and a uniform initial alignment of the liquid crystal 104 when no voltage is applied can be realized. That is, the liquid crystal 104 is not completely vertically aligned with respect to the substrate surface, and the liquid crystal 104 at the substrate interface has a small pretilt angle, and the initial alignment of the substantially vertical alignment can be uniformly achieved.

Further, in the liquid crystal display element 100 of the present embodiment, the alignment film 140 and the alignment film 144 on the opposite substrate 103 to be described later are not provided, or the alignment film 140 and the alignment film 144 are provided, and then mixed in the liquid crystal 104. The photopolymerizable monomer is photopolymerized, whereby the initial alignment of the liquid crystal 104 can be achieved.

The liquid crystal display element 100 has an opposite substrate 103 as a second substrate sandwiching the liquid crystal 104. A black matrix 141 and a color filter 142 are formed on the counter substrate 103, and a planarizing film 143 is formed to cover the third substrate 112, and an alignment film 144 is further formed thereon.

The alignment film 144 on the counter substrate 103 is the same as the alignment film 140 on the TFT substrate 102, and is subjected to an appropriate alignment treatment to form an initial alignment of the liquid crystal 104, thereby achieving a substantially vertical alignment.

The liquid crystal display element 100 has a third electrode 112 on the counter substrate 103. Further, in the liquid crystal display element 100 of the present embodiment, the third electrode 112 constitutes a common electrode shared with other pixels.

In the liquid crystal display device 100 of the present embodiment having the above configuration, a video signal is applied to the first electrode 108 and the second electrode 110 on the TFT substrate 102 in order to display an image, and the first and the opposite electrodes 103 are applied to the opposite substrate 103. When a voltage is applied between the three electrodes 112, an electric field is generated between these. In other words, by applying a voltage between the first electrode 108 and the second electrode 110 and the third electrode 112, an electric field perpendicular to the substrate surface of the TFT substrate 112 is generated in the liquid crystal 104.

As a result, the liquid crystal 104 having a negative dielectric anisotropy is driven by the electric field, and the tilting operation is performed so as to be aligned in a direction parallel to the substrate surface from a state of being substantially perpendicularly aligned as the initial alignment.

The liquid crystal display element 100 has a polarizing plate (not shown) on the surface on the counter liquid crystal side of the TFT substrate 102 and the counter liquid crystal side surface of the counter substrate 103, and the liquid crystal 104 is sandwiched by a pair of polarizing plates. Therefore, the liquid crystal display element 100 can partially transmit and block light due to the alignment change of the liquid crystal 104 by the vertical electric field, and can display an image using such characteristics.

Further, in the liquid crystal display element 100, the contact hole 107 provided in the TFT substrate 102 is filled with the second insulating film 109, and the surface of the TFT substrate 102 is flattened. Therefore, in the liquid crystal display element 100, the phenomenon that the alignment of the liquid crystal 104 caused by the contact hole 107, the transmittance due to the recess, and the response characteristic of the liquid crystal 104 are lowered are reduced. In other words, the liquid crystal display element 100 can reduce the influence of the contact hole 107 provided on the TFT substrate 102, and it is not necessary to form a light shielding mechanism such as the source electrode 134, and the luminance characteristics can be improved.

Further, the liquid crystal of the second embodiment of the present invention shown in FIG. 4 and the like In the display element 100, the contact hole 107 is filled with the second insulating film 109. Moreover, the surface height of the TFT substrate 102 is uniformly flattened. Further, in the liquid crystal display device 100 of the present embodiment, the selection of the composition of the second radiation-sensitive resin composition for forming the second insulating film 109 or the method of forming the second insulating film 109 may be performed in a plurality of depressions. 2 Upper surface of the insulating film 109 (surface on the liquid crystal 104 side).

FIG. 6 is a cross-sectional view showing a configuration of another example of a VA mode liquid crystal display element according to a second embodiment of the present invention.

In addition, the VA mode liquid crystal display element 100-2 which is another example of the second embodiment of the present invention shown in FIG. 6 has a shape different from that of FIG. 4 and the like except for the shape of the second insulating film 109-2. The liquid crystal display element 100 has the same structure. Therefore, the same constituent elements are denoted by the same reference numerals, and the overlapping description will be omitted.

In the VA mode liquid crystal display element 100-2 which is another example of the second embodiment of the present invention, the upper surface of the second insulating film 109-2 on which the second electrode 110-2 is provided is recessed (liquid crystal 104) Side surface). In the liquid crystal display device 100-2, the contact hole 7 provided in the TFT substrate 102 is filled with the second insulating film 109-2, and the surface of the TFT substrate 102 is not provided with the second insulating film 109-2. It is flattened. Therefore, in the liquid crystal display element 100-2, the alignment disorder of the liquid crystal 104 caused by the contact hole 107 is reduced as compared with the case where the second insulating film 109-2 is not provided, and the transmittance due to the recess is alleviated. And the response characteristics of the liquid crystal 104 are lowered. That is, the liquid crystal display element 100-2 can reduce the influence of the contact hole 107 provided on the TFT substrate 102, and it is not necessary to form a shutter such as the source 134. The structure can improve the brightness characteristics.

In the liquid crystal display device of the first embodiment and the second embodiment of the present invention, the first radiation sensitive resin composition for forming the first insulating film and the contact for filling the first insulating film The second radiation sensitive resin composition of the pores will be described in more detail.

Embodiment 3.

<1st sense radiation linear resin composition>

The first radiation-sensitive resin composition of the third embodiment of the present invention can be suitably used in the formation of the first insulating film of the liquid crystal display device of the first embodiment and the second embodiment of the present invention. The first radiation sensitive resin composition of the present embodiment can selectively have any sense radiation of a positive type and a negative type.

The first radiation-sensitive resin composition of the present embodiment contains an alkali-soluble resin as an essential component in both the positive type and the negative type, and contains a photo-acid generator as an essential component in the case of a positive-type radiation-sensitive resin composition. In the case of a negative-type radiation-sensitive resin composition, a polymerizable compound and a radiation-sensitive linear polymerization initiator are contained.

The alkali-soluble resin may be a polymer containing a constituent unit having a carboxyl group and a constituent unit having a polymerizable group, and is preferably an acrylic resin, a polyoxyalkylene oxide, a polybenzoxazole, or a polyglycine. A polyimine resin, a novolak resin, a cycloolefin resin, or the like obtained by ruthenium imidization in a ring closure.

Further, it is preferable to include a thermally crosslinkable group such as an epoxy group, an oxetanyl group or a (meth)acryl fluorenyl group in the constituent unit of the alkali-soluble resin, and an alkali-soluble resin may also be used. It is used in combination with a resin which additionally contains a thermally crosslinkable group such as an epoxy group, an oxetanyl group or a (meth) acrylonitrile group.

By using such a resin containing a thermally crosslinkable group, heat resistance and solvent resistance of the obtained insulating film can be improved.

Further, examples of the acid generator used in the positive first radiation sensitive resin composition include a quinonediazide compound or an oxime sulfonate compound, a sulfonium salt, a sulfone imide compound, and the like. A halogen compound, a diazomethane compound, a hydrazine compound, a sulfonate compound, a carboxylate compound, or the like. Among these, a quinonediazide compound or an oxime sulfonate compound, a phosphonium salt, and a quinone imine compound are particularly preferable.

In addition, examples of the polymerizable compound used in the negative first radiation sensitive resin composition include ω-carboxypolycaprolactone mono(meth)acrylate and ethylene glycol (meth)acrylate. 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(methyl) Acrylate, polypropylene glycol di(meth)acrylate, bisphenoxyethanol hydrazine di(meth) acrylate, dimethylol tricyclodecane di(meth) acrylate, methacrylic acid-2- Hydroxy-3-(meth)acryloxypropyl propyl ester, 2-(2'-vinyloxyethoxy)ethyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tris(2-(methyl) propylene oxychloride Ethyl ethyl ester, ethylene oxide modified dipentaerythritol hexaacrylate, succinic acid modified pentaerythritol triacrylate, etc., and having a linear alkyl and alicyclic structure A (meth)acrylic acid amine group obtained by reacting a compound having two or more isocyanate groups with a compound having one or more hydroxyl groups in the molecule and having three to five (meth)acryloxy groups. An acid ester compound or the like.

In addition, examples of the radiation-sensitive polymerization initiator used in the negative first radiation sensitive resin composition include an O-indenyl hydrazine compound, an acetophenone compound, and a biimidazole compound. These compounds may be used singly or in combination of two or more.

Among these radiation-sensitive polymerization initiators, an O-mercaptopurine compound is particularly preferable, and specifically, 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzene) is preferred.醯肟)], Ethyl Ketone-1-[9-Ethyl-6-(2-methylbenzylidene)-9H-indazol-3-yl]-1-(O-acetamidine), B Keto-1-[9-ethyl-6-(2-methyl-4-tetrahydrofurylmethoxybenzylidene)-9.H.-carbazol-3-yl]-1-(O-B醯肟) or ethyl ketone-1-[9-ethyl-6-{2-methyl-4-(2,2-dimethyl-1,3-dioxolyl)methoxybenzene Formamyl}-9.H.-carbazol-3-yl]-1-(O-acetamidine).

The first radiation-sensitive resin composition of the present embodiment may contain metal oxide particles as needed. By including the oxide particles of the metal as described above, the film properties of the obtained cured film such as the refractive index and the dielectric constant can be improved.

The metal oxide particles may be oxide particles of at least one metal selected from the group consisting of aluminum, zirconium, titanium, zinc, indium, tin, antimony and bismuth, and among them, oxide particles of zirconium, titanium or zinc are preferred. More preferred are oxide particles of zirconium or titanium. Further, in addition to these, titanate may be used instead of these metal oxide particles.

These metal oxide particles may be used alone or in combination of two or more. Used in combination. Further, the metal oxide particles may be composite oxide particles of the above-exemplified metals. Examples of the composite oxide particles include Antimony-Tin Oxide (ATO), ITO, and Indium-Zinc Oxide (IZO). These metal oxide particles can be used commercially. For example, Nanotec or the like of C.I. Kasei CO., LTD. can be used.

Embodiment 4.

<Second-sensing radiation resin composition>

The second radiation-sensitive resin composition of the fourth embodiment of the present invention can be suitably used for forming the second insulating film of the liquid crystal display device of the first embodiment and the second embodiment of the present invention. The second radiation-sensitive resin composition of the present embodiment may selectively have any sense radiation of a positive type and a negative type.

In the case of forming the first radiation-sensitive resin composition of the liquid crystal display device of the present invention, when the first radiation-sensitive resin composition of the third embodiment of the present invention is selected as the positive radiation-sensitive resin composition, The second sensation radiation resin composition of the embodiment may selectively have a negative susceptibility radiation. By performing the above, in the production of the liquid crystal display device of the present invention, the formation of the first insulating film and the second insulating film can be realized by using the same photomask as described above.

In the same manner as the first radiation sensitive resin composition of the third embodiment of the present invention, the second radiation-sensitive resin composition of the present embodiment contains an alkali-soluble resin as an essential component, whether it is a positive type or a negative type. Further, when the second radiation sensitive resin composition is a positive radiation sensitive resin composition, a photoacid generator is contained as an essential component, and in the case of a negative radiation sensitive resin composition, Contains a polymerizable compound and a radiation-sensitive polymerization initiator.

The alkali-soluble resin may be a polymer containing a constituent unit having a carboxyl group and a constituent unit having a polymerizable group, and is preferably an acrylic resin, a polyoxyalkylene oxide, a polybenzoxazole, or a polyglycine. A polyimine resin, a novolak resin, a cycloolefin resin, or the like obtained by ruthenium imidization in a ring closure.

Further, it is preferable that the structural unit of the alkali-soluble resin contains a thermally crosslinkable group such as an epoxy group, an oxetanyl group or a (meth) acrylonitrile group, and the alkali-soluble resin may additionally contain an epoxy group. A resin of a thermally crosslinkable group such as an oxetanyl group or a (meth) acrylonitrile group is used in combination.

By using such a resin containing a thermally crosslinkable group, heat resistance and solvent resistance of the obtained insulating film can be improved.

Further, examples of the acid generator used in the positive second radiation sensitive resin composition include a quinonediazide compound, an oxime sulfonate compound, a phosphonium salt, a quinone imine compound, and a halogen-containing compound. A diazomethane compound, an anthracene compound, a sulfonate compound, a carboxylate compound, or the like. Among these, a quinonediazide compound or an oxime sulfonate compound, a phosphonium salt, and a quinone imine compound are particularly preferable.

In addition, examples of the polymerizable compound used in the negative-type second radiation-sensitive resin composition include ω-carboxypolycaprolactone mono(meth)acrylate and ethylene glycol (meth)acrylate. 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(methyl) Acrylate, polypropylene glycol di(meth)acrylate, bisphenoxyethanol hydrazine di(meth) acrylate, dimethylol tricyclodecane di(meth) acrylate, methyl propyl 2-Hydroxy-2-(methyl)propenyl propyl acrylate, 2-(2'-vinyloxyethoxy)ethyl (meth)acrylate, Trimethylolpropane Acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, phosphoric acid tris(2-(A) Ethylene oxy oxyethyl ester, ethylene oxide modified dipentaerythritol hexaacrylate, succinic acid modified pentaerythritol triacrylate, etc., and having a linear alkyl and alicyclic structure and having 2 A (meth)acrylic acid urethane compound obtained by reacting a compound having one or more isocyanate groups with a compound having one or more hydroxyl groups in the molecule and having three to five (meth) acryloxy groups.

In addition, examples of the radiation-sensitive polymerization initiator used in the negative-type second radiation-sensitive resin composition include an O-indenyl hydrazine compound, an acetophenone compound, and a biimidazole compound. These compounds may be used singly or in combination of two or more.

Among these radiation-sensitive polymerization initiators, an O-mercaptopurine compound is particularly preferable, and specifically, 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzene) is preferred.醯肟)], Ethyl Ketone-1-[9-Ethyl-6-(2-methylbenzylidene)-9H-indazol-3-yl]-1-(O-acetamidine), B Keto-1-[9-ethyl-6-(2-methyl-4-tetrahydrofurylmethoxybenzylidene)-9.H.-carbazol-3-yl]-1-(O-B醯肟) or ethyl ketone-1-[9-ethyl-6-{2-methyl-4-(2,2-dimethyl-1,3-dioxolyl)methoxybenzene Formamyl}-9.H.-carbazol-3-yl]-1-(O-acetamidine).

The second radiation-sensitive resin composition of the present embodiment may contain metal oxide particles as needed. By containing oxide particles of a metal as described above, The film properties such as the refractive index and dielectric constant of the obtained cured film can be improved.

The metal oxide particles may be oxide particles of at least one metal selected from the group consisting of aluminum, zirconium, titanium, zinc, indium, tin, antimony and bismuth, and among them, oxide particles of zirconium, titanium or zinc are preferred. More preferred are oxide particles of zirconium or titanium. Further, in addition to these, titanate may be used instead of these metal oxide particles. The titanate is preferably barium titanate or the like.

These metal oxide particles may be used alone or in combination of two or more. Further, the metal oxide particles may be composite oxide particles of the above-exemplified metals. Examples of the composite oxide particles include Antimony-Tin Oxide (ATO), ITO, and Indium-Zinc Oxide (IZO). These metal oxide particles can be used commercially. For example, Nanotec et al. of C.I. Kasei CO., LTD. can be used.

[Examples]

Hereinafter, the embodiments of the present invention will be described in detail based on the examples, but the present invention is not limited by the examples.

Example 1

[Synthesis of Alkali Soluble Resin (A-I)]

In a flask equipped with a condenser and a stirrer, 8 parts by mass of 2,2'-azobis(2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether were charged. Then, 15 parts by mass of methacrylic acid, 45 parts by mass of -3,4-epoxycyclohexylmethyl methacrylate, 20 parts by mass of methyl methacrylate, 5 parts by mass of styrene, and N-cyclohexyl horse were charged. 15 parts by mass of imine, after nitrogen substitution, slowly stirring and allowing the solution The temperature was raised to 70 ° C, and the temperature was maintained for 5 hours to carry out polymerization, whereby a solution containing the copolymer (A-I) was obtained. The solid content concentration of the obtained polymer solution was 31.9% by mass, the Mw of the copolymer (A-I) was 10,000, and the molecular weight distribution (Mw/Mn) was 2.1. Further, the solid content concentration is a ratio indicating the mass of the copolymer in the total mass of the polymer solution.

Example 2

[Synthesis of Alkali Soluble Resin (A-II)]

144 parts by mass of propylene glycol monomethyl ether was placed in a container equipped with a stirrer, followed by 13 parts by mass of methyltrimethoxydecane and 5 parts by mass of 3-methylpropenyloxypropyltriethoxydecane. 6 parts by mass of phenyltrimethoxydecane was heated until the solution temperature became 60 °C. After the solution temperature reached 60 ° C, 7 parts by mass of ion-exchanged water was charged, and the mixture was heated to 75 ° C for 3 hours. Next, 25 parts by mass of methyl orthoformate as a dehydrating agent was added and stirred for 1 hour. Further, the temperature of the solution was changed to 40 ° C, and evaporation was carried out while maintaining the temperature, whereby the alcohol and the alcohol produced by hydrolysis condensation were removed. According to the above procedure, a siloxane polymer as the component (A-II) was obtained. The obtained hydrolysis condensate had a number average molecular weight (Mn) of 2,500 and a molecular weight distribution (Mw/Mn) of 2.

Example 3

[Preparation of positive type first sense radiation linear resin composition]

A solution containing an alkali-soluble resin (AI) as an alkali-soluble resin is prepared in an amount equivalent to 100 parts by mass (solid content) of the polymer, and then 4, 4'-[1 of a quinonediazide compound as a photoacid generator is mixed. -[4-[1-[4-hydroxyphenyl]-1-methylethyl] 30 parts by mass of phenyl]ethylidene bisphenol (1.0 mol), and further, diethylene glycol ethyl methyl ether was added so that the solid content concentration became 30% by mass, and the respective components were dissolved, and the pore diameter was 0.2 μm. The membrane filter was filtered to prepare a first radiation sensitive linear resin composition having a positive type of radiation.

Example 4

[Preparation of Negative Type Second Sensitive Radiation Resin Composition]

A solution containing an alkali-soluble resin (A-II) as an alkali-soluble resin is prepared in an amount corresponding to 100 parts by mass (solid content) of the polymer, and secondly mixed with dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate as a polymerizable compound 100 parts by mass of a mixture (KAYARAD (registered trademark) DPHA (Japan Chemicals Co., Ltd.)) and ethyl ketone-1-[9-ethyl-6- (as a radiation-sensitive polymerization initiator) 2-Methylbenzylidene)-9H-indazol-3-yl]-1-(O-acetamidine) (Irgacure OXE02, BASF) 5 parts by mass, solid When the component concentration was 30% by mass, propylene glycol monomethyl ether acetate was added to dissolve each component, and then filtered with a micropore filter having a pore diameter of 0.5 μm to prepare a second sense having a negative radiation sensitivity. A linear resin composition.

Example 5

[Preparation of positive type third sense radiation linear resin composition]

A solution containing an alkali-soluble resin (AI) as an alkali-soluble resin is prepared in an amount equivalent to 100 parts by mass (solid content) of the polymer, and then 4, 4'-[1 of a quinonediazide compound as a photoacid generator is mixed. -[4-[1-[4-Hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol (1.0 mol) 30 parts by mass, containing titanium as a metal particle 50 parts by mass (solid content) of the acid bismuth dispersion, diethylene glycol ethyl methyl ether was added so that the solid content concentration was 30% by mass, and the respective components were dissolved, and then filtered using a membrane filter having a pore size of 0.2 μm. A third radiation sensitive linear resin composition having a positive type of radiation sensitivity was prepared.

Example 6

[Evaluation of membrane]

The first radiation sensitive resin composition prepared in Example 3, the second radiation sensitive resin composition prepared in Example 4, and the third radiation sensitive resin composition prepared in Example 5 were used, respectively. Each composition was applied onto a glass substrate ("Corning (trademark) 7059" (manufactured by Corning)) using a spin coater, and then prebaked on a hot plate at 100 ° C for 2 minutes to form a coating film. A film having a film thickness of 1 μm was formed on the glass substrate.

Next, a PLA (registered trademark)-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon Co., Ltd. was used for the coating film on each of the obtained glass substrates, and a mask having a rectangular pattern of 5 cm × 8 cm was used. Exposure. Thereafter, development was carried out for 60 seconds at 25 ° C in a 2.38 mass% aqueous solution of tetramethylammonium hydroxide. Next, the water-washing was performed for 1 minute with ultrapure water to form a cured film which was patterned so as to have a rectangular negative pattern or a positive pattern of 5 cm × 8 cm.

Then, the end portion of each of the patterned cured films was observed with an optical microscope, and it was judged that the patterning property was good in the case where no development residue was formed and the pattern was linearly formed.

As a result, the first radiation sensitive resin prepared in Example 3 was used, respectively. Each of the cured films formed by patterning the composition of the second radiation-sensitive resin composition prepared in Example 4 and the third radiation-sensitive resin composition prepared in Example 5 was excellent in patterning property.

Next, an insulating film was formed by heating each of the above-mentioned cured films in a clean oven at 220 ° C for 1 hour.

The light transmittance of the glass substrate on which the insulating film was formed was measured using a spectrophotometer "150-20 type Double-beam" (manufactured by Hitachi, Ltd.) at a wavelength in the range of 400 nm to 800 nm. If the minimum light transmittance is 90% or more, it can be said that the light transmittance is good.

The first radiation sensitive resin composition prepared in Example 3, the second radiation sensitive resin composition prepared in Example 4, and the third radiation sensitive resin composition prepared in Example 5 were formed. Each of the insulating films has a transmittance of 90% or more.

From the results of the above film evaluation, it was found that the insulating film formed of the first radiation sensitive resin composition prepared in Example 3 and the second radiation sensitive resin composition prepared in Example 4 were formed. The insulating film formed of the insulating film and the third radiation-sensitive resin composition prepared in the fifth embodiment can be suitably used as the first insulating film or the second insulating film of the liquid crystal display device of the present invention.

[Industrial availability]

The liquid crystal display element of the present invention is an active matrix type liquid crystal display element which has excellent luminance characteristics and can perform high definition display. Therefore, the liquid crystal display element of the present invention can be used as an intelligent type that requires high-definition display with excellent image quality. A display of a portable electronic device such as a mobile phone is suitably used.

Claims (6)

A liquid crystal display element in which a liquid crystal is sandwiched between a first substrate and a second substrate which are disposed opposite to each other, wherein the first substrate includes a thin film transistor and a first insulating film, and is used. a first radiation-sensitive resin composition is provided on the thin film transistor and has a contact hole formed in the first insulating film and the first electrode, and is disposed on the first insulating film and in the contact hole The wall is electrically connected to the thin film transistor via the contact hole, and the second insulating film is provided with the second radiation sensitive resin composition and the second electrode so as to fill the contact hole. Provided on the second insulating film, a part of which is in contact with the first electrode portion on the first insulating film, and is electrically connected to the first electrode; and the third electrode is passed through 3, an insulating film is provided on the first electrode and the second electrode of the first substrate; and a voltage is applied between the first electrode and the second electrode and the third electrode to drive The liquid crystal is constructed in a manner. The liquid crystal display device according to claim 1, wherein the first radiation sensitive resin composition is a positive radiation sensitive resin composition and the second radiation sensitive resin composition is negative. Radiation-sensitive resin composition, Or the first radiation sensitive resin composition is a negative radiation sensitive resin composition, and the second radiation sensitive resin composition is a positive radiation sensitive resin composition. The liquid crystal display device according to the first or second aspect, wherein the first radiation sensitive resin composition contains a polymer comprising a constituent unit having a carboxyl group and a polymerizable group. Form the unit. The liquid crystal display device according to claim 1 or 2, wherein the second radiation sensitive resin composition contains a polymer comprising a constituent unit having a carboxyl group and a polymerizable group. Form the unit. A radiation-sensitive resin composition which is a radiation-sensitive resin composition used for the production of a liquid crystal display element in which a liquid crystal is sandwiched between a first substrate and a second substrate which are disposed opposite to each other, and is characterized in that: The first substrate includes a thin film transistor and a first insulating film, and is provided on the thin film transistor and has a contact hole formed in the first insulating film and the first electrode, and is provided on the first insulating film and The inner wall of the contact hole is electrically connected to the thin film transistor via the contact hole, and the second insulating film is provided to fill the contact hole, and the second electrode is provided in the a second insulating film is in contact with the first electrode portion on the first insulating film, and is electrically connected to the first electrode; The liquid crystal display element is such that the third electrode and the second electrode are provided on the first electrode and the second electrode of the first substrate via the third insulating film, and the first electrode and the second electrode are The liquid crystal is applied between the electrode and the third electrode to drive the liquid crystal, and the radiation sensitive resin composition is used to form the second insulating film of the first substrate. The radiation sensitive resin composition according to claim 5, further comprising metal oxide particles.