Japan Display Inc.

Panasonic Liquid Crystal Display Co., Ltd.

Hitachi Displays, Ltd.

Hitachi, Ltd.

Panasonic Intellectual Property Corporation of America

Panasonic Liquid Crystal Co., Ltd.

Noboru Kunimatsu

Hidehiro Sonoda

Yasushi Tomioka

Chikae Matsui

Yuko Matsumoto

Masaki Matsumori

Yosuke Hyodo

Toshiki Kaneko

Shoichi Uchino

Jun Tanaka

Yasuo Imanishi

Koichi Igeta

Tomio Yaguchi

Takenori Hirota

Masateru Morimoto

Atsuhiro Katayama

Shigeru Matsuyama

Takashi Yamamoto

Setsuo Kobayashi

Shuji Imazeki

Toshiyuki Higano

Masahiro Kosuge

Aki Sakai

Katsumi Kondo

Yukio Tanaka

Tohru Sasaki

Masamitsu Furuie

Kazuhiro Nishiyama

Yoshitada Oshida

Takeshi Sato

Daiichi Suzuki

Nagatoshi Kurahashi

Yoshinori Yamamoto

Hiroaki Asuma

Masanao Yamamoto

Yoshifumi Saeki

Daisuke Miyazaki

Aki Tsuchiya

Midori Tsukane

Yojiro Shimada

Ryoichi Tabuchi

In a liquid crystal display device, a common electrode is formed on an organic passivation film, an interlayer insulating film is formed on the common electrode, a pixel electrode with a slit is formed on the interlayer insulating film, and a through hole is formed in the organic passivation film and the interlayer insulating film, so that the pixel electrode is connected to a source electrode of a TFT through the through hole. Further, the taper angle around the upper base of the through hole is smaller than the taper angle around the lower base. Thus, the alignment film material can easily flow into the through hole when the diameter of the through hole is reduced to connect the pixel and source electrodes, preventing display defects such as uneven brightness due to the absence of the alignment film or due to the alignment film irregularity around the through hole.

Liquid crystal display device

Disclosed is a manufacturing method of a liquid crystal display device which is a manufacturing method of a liquid crystal display device including a liquid crystal alignment film to which an alignment regulating force is imparted by a photo-alignment treatment, including: a film forming step of forming a film containing a polymer whose main chain is cleaved by irradiation with light; a photo-alignment step of imparting an alignment regulating force to the film formed in the film forming step by irradiation of the film with light in an atmosphere of a temperature lower than 100° C.; and a removing step of removing a low-molecular weight component generated by cleaving the main chain of the polymer through the light irradiation after the light irradiation. Also disclosed is a liquid crystal display device manufactured by the manufacturing method.

Liquid crystal display device and manufacturing method thereof

Disclosed is a manufacturing method of a liquid crystal display device which is a manufacturing method of a liquid crystal display device including a liquid crystal alignment film to which an alignment regulating force is imparted by a photo-alignment treatment, including: a film forming step of forming a film containing a polymer whose main chain is cleaved by irradiation with light; a photo-alignment step of imparting an alignment regulating force to the film formed in the film forming step by irradiation of the film with light in an atmosphere of a temperature lower than 100&#xb0; C.; and a removing step of removing a low-molecular weight component generated by cleaving the main chain of the polymer through the light irradiation after the light irradiation. Also disclosed is a liquid crystal display device manufactured by the manufacturing method.

In a liquid crystal display device, a common electrode is formed on an organic passivation film, an interlayer insulating film is formed on the common electrode, a pixel electrode with a slit is formed on the interlayer insulating film, and a through hole is formed in the organic passivation film and the interlayer insulating film, so that the pixel electrode is connected to a source electrode of a TFT through the through hole. Further, the taper angle around the upper base of the through hole is smaller than the taper angle around the lower base. Thus, the alignment film material can easily flow into the through hole when the dimeter of the through hole is reduced to connect the pixel and source electrodes, preventing display defects such as uneven brightness due to the absence of the alignment film or due to the alignment film irregularity around the through hole.

An alignment film is given a 2-layer structure comprising a photoalignment film that is photoalignable and a low-resistivity alignment film whose resistivity is smaller than that of the photoalignment film. The photoalignment film is formed by a polyimide whose precursor is polyamide acid alkyl ester, the number molecular weight of the photoalignment film is large, and the stability of alignment of the photoalignment film by photoalignment is excellent. The low-resistivity alignment film is formed by a polyimide whose precursor is polyamide acid, the number molecular weight of the low-resistivity alignment film is small, and the resistivity of the low-resistivity alignment film is small. The 2-layer structure alignment film can be maintaining an excellent photoalignment characteristic, so DC afterimages can be controlled.

A liquid crystal display device includes a TFT substrate and a counter substrate and a liquid crystal layer sandwiched therebetween. A scanning line, a video signal line, a thin film transistor connected to the scanning line and the video signal line, a pixel electrode connected to the thin film transistor, and a counter electrode are formed on the TFT substrate, and a columnar spacer formed on the counter substrate. The pixel and counter electrodes are transparent, and the liquid crystal layer is controlled by an electric field generated between the pixel and counter electrodes. The counter electrode contacts with a metal line having a first part which is extended in parallel with the scanning line and a second part which is extended in parallel with the video signal line, a width of the first part of the metal line being narrower than a width of the scanning line.

According to one embodiment, a varnish for a photo alignment film includes an imidization promotor and a first polyamic acid-based compound in an organic solvent. The first polyamic acid-based compound is a polyamic acid or a polyamic acid ester. The imidization promotor has skeleton containing no primary amino group and no secondary amino group. The first polyamic acid-based compound has terminal skeletons containing no primary amino group.

Varnish for photo alignment film and liquid crystal display device

The present invention prevents the shaving of an alignment film caused by a columnar spacer in a liquid crystal display device of an IPS method using photo-alignment. A plinth higher than a pixel electrode is formed at a part where a columnar spacer formed over a counter substrate touches a TFT substrate. When an alignment film of a double-layered structure is applied over the pixel electrode and the plinth, the thickness of the alignment film over the plinth reduces by a leveling effect. When photo-alignment is applied in the state, a photodegraded upper alignment film over the plinth disappears and a lower alignment film having a high mechanical strength remains. As a result, it is possible to prevent the shaving of the alignment film.

A liquid crystal display device includes a first substrate, a first alignment film formed over the first substrate, a second substrate, a second alignment film formed over the second substrate, a liquid crystal layer sandwiched between the first alignment film and the second alignment film, and a projecting portion formed over the second substrate. The first film is a photo alignment film, and a thickness 'd2' of the second alignment film over the projecting portion and a film thickness 'd1' of a portion of the first alignment film facing the projecting portion satisfy formula (2),d2&#x3c;d1&#x2003;&#x2003;(2).

Liquid crystal display device having alignment films

A liquid crystal display device includes a TFT substrate having a first alignment film and an opposing substrate having a second alignment film with liquid crystals sandwiched therebetween. One of the first and second alignment films, comprises a first polyimide produced via polyamide acid ester containing cyclobutane as a precursor and a second polyimide produced via polyamide acid as a precursor. The polyamide acid has a higher polarity than that of the polyamide acid ester. The one of the first and second alignment films is responsive to photo-alignment. A first side of the one of the first and second alignment films is adjacent to the liquid crystals, and a second side thereof is closer to one of the TFT substrate and the counter substrate than the first side. The first side contains more of the first polyimide and less of the second polyimide than the second side.

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Chiba, Japan

Noboru Kunimatsu