JP5318486B2 - Liquid crystal display panel and manufacturing method thereof - Google Patents

Description

  The present invention relates to a liquid crystal display panel and a method for manufacturing the same.

  FIG. 10 is a cross-sectional view showing a structure in the vicinity of a frame of a conventional liquid crystal display panel. The liquid crystal display panel 1 includes a TFT substrate 2 on which switching elements such as thin film transistors (TFTs) are formed in a matrix, and a CF substrate on which a color filter (CF), a black matrix (BM), and the like are formed. 3 and an alignment film 9 subjected to an alignment process is formed on the opposing surfaces of these substrates. Then, in order to form a predetermined gap (gap) between the two substrates, the column spacer 10 and the sealing material 5 are formed, and the liquid crystal material 4 is sealed in the gap.

  Here, FIG. 11 shows a flow of a bonding process of a conventional liquid crystal display panel. In the seal application process, a sealing material is applied to a predetermined position of the TFT substrate to form an outer peripheral (auxiliary) seal and a main seal. Subsequently, in the Ag application process, the Ag transfer is formed in a dot pattern at a predetermined position of the TFT substrate. The liquid crystal display panel of TN (Twisted Nematic) mode was applied. Next, in the liquid crystal dropping step, the liquid crystal material was dropped at a predetermined drop amount in a matrix shape, a linear shape, or a radial shape at a predetermined position inside the main seal.

  Next, column spacers or spherical spacers for forming a predetermined gap between the substrates are arranged in advance in the pixel region of the CF substrate, and the substrates are brought into contact with each other and pressed in the bonding step. The gap between the substrates was formed uniformly while the liquid crystal material was uniformly diffused throughout the pixel region.

  And in order to prevent the fitting shift | offset | difference of a bonding board | substrate at the time of conveyance to the next process, UV temporary hardening of several places was performed partially as temporary fixing of a sealing material. At this time, the liquid crystal material diffused over time, and passed from the pixel region to the outer frame BM formation region to reach the sealing material. In the next UV curing step, the sealing material was cured by UV irradiation, but the uncured sealing material and the liquid crystal material were already in contact. Furthermore, in the next thermosetting step, the sealing material was completely cured, but at this time, the initial semi-cured sealing material and the liquid crystal material were kept in contact with each other.

  As described above, in the conventional structure, the uncured or semi-cured sealing material and the liquid crystal material come into contact with each other in the bonding process, the UV curing process, or the thermal curing process, so that impurities are sealed as shown in FIG. The problem that the liquid material 4 was eluted from the material 5 and contaminated the liquid crystal material 4 occurred. Examples of substances that contaminate the liquid crystal material 4 include oligomer components that dissolve from the uncured or semi-cured seal material 5, organic substances such as phthalate esters, and ionic impurities such as Na, K, and Cl. Further, the liquid crystal material 4 comes into contact with the uncured or semi-cured sealing material 5, and the liquid crystal material 4 erodes the interface between the sealing material 5 and its base, so that the substrate interface to which the sealing material 5 is applied is applied. There has been a problem that the seal adhesive strength is lowered at the portion. As a result, there have been problems in the display quality and reliability of the liquid crystal display device such as spots, unevenness, and peeling of the seal in the periphery of the seal of the liquid crystal display panel after the reliability test.

  As a technique for solving the problem of contamination of the liquid crystal material caused by contact between the uncured or semi-cured sealing material and the liquid crystal material, and the problem of decrease in the adhesive strength of the sealing material, (1) a barrier was used. There are technologies and (2) technologies for increasing the surface energy.

  As shown in FIG. 12, the technique using the barrier (1) technique forms a convex portion 12 in the pixel region of the TFT substrate 2 and a region where the sealing material 5 is applied, and the convex portion 12 The diffusion of the liquid crystal material 4 is temporarily suppressed by adjusting the distance from the substrate facing the convex portion 12. As conventional examples of this method, there are JP-A-11-38424 and JP-A-2003-315810. In JP-A-11-38424, the pixel region of the TFT substrate and the region where the sealing material 5 is applied are projected. It is disclosed that a portion 12 is formed and a vertical alignment film is formed as an alignment film on the top of the convex portion 12. Japanese Patent Laid-Open No. 2003-315810 discloses that a large number of flow control walls 13 of the liquid crystal material 4 are formed in a pixel region or in and outside a pixel region as shown in FIG.

  As a conventional example relating to the technique for increasing the surface energy of (2), there is JP-A-10-260406. In this publication, the orientation of the display region is modified by surface modification of the alignment film at a position away from the display region. It discloses that the surface energy is higher than that of the film.

JP 11-38424 A JP 2003-315810 A JP-A-10-260406

  However, the suppression method disclosed in Japanese Patent Application Laid-Open No. 11-38424 performs liquid crystal diffusion control with the vertical alignment film and the projections, and is only applicable to liquid crystal display panel varieties using a vertical alignment film that has low wettability to a liquid crystal material. There is a problem that the effect cannot be obtained and the liquid crystal diffusion rate cannot be reduced when a normal alignment film is used. Further, in order to reduce the liquid crystal diffusion speed, it is necessary to form a convex portion in a wide area in the periphery of the seal, so that the convex portion is opposed depending on how the convex portion height varies. A problem of local contact with the substrate occurs, and local stress is generated by this contact, resulting in gap variation in the periphery of the seal. As a result, display quality deteriorates at the boundary between the frame BM and the pixel region. This problem becomes more noticeable as the distance between the convex portion and the substrate becomes shorter.

  In addition, in the suppression method according to Japanese Patent Laid-Open No. 2003-315810, it is possible to temporarily suppress the diffusion of liquid crystal by arranging a large number of flow control walls, but in the pixel region or in the pixel region and outside the pixel region. Since a large number of flow control walls are arranged so as to be in contact with the opposing substrate, gap variation due to contact stress in the pixel region and the seal peripheral portion is caused. As a result, the display quality of the pixel area is degraded, and the display quality is degraded at the boundary between the frame BM and the pixel area.

  In addition, the suppression method according to Japanese Patent Laid-Open No. 10-260406 discloses that the alignment film at a position away from the display region has a surface energy higher than that of the alignment film in the display region, so that the liquid crystal material is changed from the sealing material after the liquid crystal display panel is manufactured. It is only manufactured by adsorbing the ionic impurities that have been dissolved out or adsorbed and suppressing diffusion into the liquid crystal material, and the liquid crystal material is in contact with the uncured or semi-cured sealing material. It is impossible to suppress in advance the ionic impurities that are dissolved in large quantities.

  The present invention has been made in view of the above problems, and its main purpose is to suppress the contamination of the liquid crystal material and the decrease in the adhesive strength of the seal material due to impurities dissolved from the seal material, and the display of the liquid crystal display device An object of the present invention is to provide a liquid crystal display panel capable of improving the quality and reliability and a method for manufacturing the same.

  In order to achieve the above object, the present invention provides a liquid crystal between a first substrate in which a black matrix is formed in a light shielding region of a frame and a second substrate in which an organic film or an inorganic film is formed in the light shielding region. In the liquid crystal display panel, wherein the liquid crystal material is sealed by a sealing material provided on the outside of the light shielding region of at least one substrate, the first substrate and / or the second substrate in the light shielding region The contact angle with respect to the liquid crystal material is larger than the contact angle in the pixel region inside the light shielding region.

  In the present invention, a liquid repellent treatment layer that repels the liquid crystal material is formed on the black matrix of the first substrate and / or on at least a part of the organic film or the inorganic film of the second substrate. Preferably, the liquid-repellent treatment layer includes a fluorine film or a silicone film.

  According to the present invention, a substrate having a black matrix formed in a light shielding region of a frame and a substrate having an organic film or an inorganic film formed in the light shielding region are formed, and a sealing material is formed outside the light shielding region of one substrate. A liquid crystal display in which a liquid crystal material is dropped onto a region surrounded by the sealing material, the one substrate and the other substrate are bonded together, and then the sealing material is cured to seal the liquid crystal material. In the panel manufacturing method, the liquid crystal material is provided on at least a part of the light shielding region of the one substrate before the liquid crystal material is dropped and / or the other substrate before being bonded to the one substrate. The liquid crystal repellent treatment is performed to increase the contact angle of the one substrate and / or the other substrate with respect to the liquid crystal material in the light shielding region.

  According to the present invention, a first substrate in which a black matrix is formed in a light shielding region of a frame and a second substrate in which an organic film or an inorganic film is formed in the light shielding region are formed, and the second substrate A sealing material is applied to the outside of the light shielding region, a liquid crystal material is dropped on a region surrounded by the sealing material, and the second substrate and the first substrate are bonded together, and then the sealing material is cured. Then, in the method of manufacturing a liquid crystal display panel in which the liquid crystal material is sealed between the first substrate and the second substrate, the organic film of the second substrate before dropping the liquid crystal material Alternatively, at least a part of the first substrate on the inorganic film and / or the first substrate before being bonded to the second substrate is subjected to a liquid repellent treatment that repels the liquid crystal material, and the light shielding region The first substrate and / or the second substrate in It is intended to increase the contact angle with respect to the liquid crystal material of the plate.

  In the present invention, the liquid repellent treatment may include a fluorination treatment or a siliconization treatment, and the region to be subjected to the liquid repellent treatment is bonded between the two substrates and the sealing material is cured. And a diffusion rate of the liquid crystal material determined based on the contact angle and the gap between the substrates.

  As described above, in the present invention, the surface energy is reduced, that is, the wettability with respect to the liquid crystal material is reduced by forming the liquid repellent treatment layer for controlling the liquid crystal diffusion in the region between the pixel region and the sealing material as a thin film. Reduce the liquid crystal diffusion rate. Thereby, it is possible to improve the display quality and reliability of the liquid crystal display device by suppressing the contamination of the liquid crystal material and the decrease in the adhesive strength of the seal material due to impurities dissolved from the seal material.

  According to the liquid crystal display panel and the method of manufacturing the same of the present invention, it is possible to suppress the contamination of the liquid crystal material and the decrease in the adhesive strength of the seal material due to impurities dissolved from the seal material, thereby improving the display quality and reliability of the liquid crystal display device. I can do it.

  The reason is that by forming a liquid repellent treatment layer for controlling the diffusion of the liquid crystal material on the frame BM of the CF substrate and the film surface of the TFT substrate opposite to the CF substrate, that is, the light shielding portion, the wettability to the liquid crystal material is lowered. This is because the liquid crystal diffusion rate can be reduced, and the contact between the uncured or semi-cured sealing material and the liquid crystal material can be suppressed.

  Further, since it is not necessary to shorten the distance between the frame BM of the CF substrate and the TFT substrate, the required liquid crystal diffusion rate can be obtained without deteriorating the gap uniformity in the vicinity of the frame BM. This is an effective means even for a liquid crystal display device having a product design in which the sealing material and the liquid crystal material are easy to contact, such as a narrow frame structure or high-speed response. As a result, it is possible to provide a high-quality liquid crystal display device with improved reliability at each stage.

  As shown in the background art, since the diffusion of the liquid crystal material cannot be controlled in the bonding process, the UV curing process or the thermosetting process, the liquid crystal is produced by the contact between the uncured or semi-cured sealing material and the liquid crystal material. There are problems of contamination of the material and a decrease in the sealing adhesive strength, and various methods for solving this problem have been proposed.

  However, in Japanese Patent Application Laid-Open No. 11-38424, a convex portion is formed, and a vertical alignment film is formed as an alignment film on the top of the convex portion. No consideration is given to the deterioration of the uniformity of the gap around the seal due to the formation of the portion. In Japanese Patent Laid-Open No. 2003-315810, since a large number of flow control walls are arranged, the problem of contamination of the liquid crystal material is solved to some extent, but the pixel region and the seal peripheral portion by arranging a large number of flow control walls. No consideration is given to the deterioration of gap uniformity. Japanese Patent Laid-Open No. 10-260406 discloses that an impurity in a sealing material is produced after the liquid crystal display panel is manufactured by increasing the surface energy of the alignment film at a position away from the display region than the alignment film in the display region. Although the problem of contamination of the liquid crystal material due to diffusion to the surface may be solved to some extent, there is no difference in the contact between the uncured or semi-cured sealing material and the liquid crystal material. Therefore, as long as impurities are dissolved from the sealing material, it is not a fundamental countermeasure for the above problem.

  Therefore, in the present invention, a sealing material is provided on one or both of a CF substrate having a BM formed of an organic film or an inorganic film on the frame and a TFT substrate having an organic film or an inorganic film formed on the frame. In a liquid crystal display panel in which liquid crystal material is applied and sealed, liquid crystal material contamination due to contact between the liquid crystal material and the non-cured or semi-cured seal material at the time of bonding after the liquid crystal is dropped and the seal material In order to suppress a decrease in the adhesive strength, liquid crystal diffusion (refers to a phenomenon in which the liquid crystal material moves and spreads) on the frame BM of the CF substrate and / or the film surface of the TFT substrate opposite to the frame BM. The liquid crystal repellent treatment (here, the treatment for flipping the liquid crystal material) is applied. As a result, the sealing material can be prevented from coming into contact with the liquid crystal material in an uncured or semi-cured state, and a high-quality liquid crystal display device with improved reliability can be provided. Hereinafter, description will be given with reference to the drawings.

[Embodiment 1]
FIG. 1 is a cross-sectional view showing the structure in the vicinity of the frame of the liquid crystal display panel according to the first embodiment of the present invention. The liquid crystal display panel 1 includes one substrate on which switching elements such as TFTs are formed in a matrix (hereinafter referred to as TFT substrate 2) and the other substrate on which CF, BM, etc. are formed (hereinafter referred to as CF). And an organic film or an inorganic film (not shown) is formed on the frame portion (peripheral portion) of the TFT substrate 2, and the CF substrate 3 has a frame portion on the frame portion. A frame BM6 is formed. Further, an alignment film 9 subjected to at least an alignment process is formed on the opposing surfaces of these substrates. In order to form a predetermined gap (gap) between the opposing substrates, a column spacer 10 and a seal material 5 are formed, and a liquid crystal material 4 is sealed in the gap.

  Here, in order to suppress contamination of the liquid crystal material 4 due to contact between the uncured or semi-cured seal material 5 and the liquid crystal material 4 and a decrease in the adhesive strength of the seal material 5, the frame BM6 of the CF substrate 3 and The liquid crystal repellent treatment layer 11 for controlling liquid crystal diffusion is provided on the film surface of the TFT substrate 2 (hereinafter referred to as a light shielding region, which is shielded by the frame BM6). Yes. By applying the liquid repellent treatment layer 11, the surface energy of the liquid crystal material 4 at this portion (assuming an averaged uniform surface energy) is lowered. As a result, the contact angle between the liquid crystal material 4 and the substrate is increased, and wettability can be reduced.

  FIG. 2 shows the formation region of the liquid repellent treatment layer. The liquid repellent treatment layer 11 is formed in a closed curve shape between each pixel region of the TFT substrate 2 and the CF substrate 3 of the liquid crystal display panel 1 and the seal application position. Further, FIG. 3 shows a formation region of the liquid repellent treatment layer for further controlling the diffusion of the liquid crystal material. The liquid repellent treatment layer 11 is formed in a region excluding the panel corner portion between each pixel region of the TFT substrate 2 and the CF substrate 3 of the liquid crystal display panel 1 and the seal application position. This is because when the position where the liquid crystal material is dropped into the pixel area is farther from the seal application position than the panel corner, the panel corner moves from the panel side to the liquid crystal seal application position. This takes into account the relatively long arrival time.

  FIG. 4 shows an example of the liquid crystal display panel process flow of the present invention. In the liquid crystal repellent treatment process of the CF substrate, the liquid repellent treatment is performed so that the contact angle increases on the outermost surface of the frame BM between the pixel region and the seal application position. In this way, a liquid repellent treatment layer having a predetermined range set in consideration of the lead time from the bonding process out to the thermosetting process in is formed in the frame BM part. In addition, in the pixel region of the CF substrate, column spacers for forming a predetermined gap between the substrates are formed in advance. However, in the case of a CF substrate that is not formed, polymer beads, silica after completion of the liquid-repellent treatment Insulating spherical spacers such as beads may be arranged.

  On the other hand, in the liquid crystal repellent treatment process of the TFT substrate, on the film surface of the TFT substrate between the pixel region facing the liquid repellent treatment layer of the CF substrate and the seal application position, for example, an inorganic film such as SiNx or ITO, or a novolac The same liquid repellent treatment is performed on the outermost surface of the organic film. In this way, a liquid repellent treatment layer having a predetermined range is formed on the TFT substrate side in the same manner as the CF substrate.

  The above-described liquid-repellent treatment process is exemplified as a case where it is provided as the next process of the rubbing cleaning / drying process. For example, before the substrate (TFT / CF) cleaning process, which is the head of the panel manufacturing process. May be provided with a liquid repellent treatment step, and it is sufficient that the liquid crystal repellent treatment is performed before the liquid crystal dropping step regardless of whether the substrate is a TFT substrate or a CF substrate.

  Next, in the seal coating process, a sealing material is applied to a predetermined position of the TFT substrate in a closed curve shape to form an outer peripheral (auxiliary) seal and a main seal. Subsequently, in the Ag coating process, the Ag transfer is transferred to a predetermined position on the substrate. (Ag application step is performed when a TN mode liquid crystal display panel is manufactured, and this step is omitted in the IPS (In Plane Switching) mode). Next, in the liquid crystal dropping step, the liquid crystal material is dropped at a predetermined drop amount in a predetermined shape inside the main seal in a matrix shape (a large number of dots in the matrix shape), a linear shape or a radial shape.

  Thereafter, in the bonding step, the TFT substrate and the CF substrate are contacted and pressed to uniformly diffuse the liquid crystal material in the pixel region and the peripheral portion between the substrates, thereby forming a uniform gap between the substrates. At this time, in order to provide gap uniformity in the pixel region, it is better that the liquid crystal material diffuses quickly in the pixel region. This is because, when the TFT substrate and the CF substrate are brought into contact with each other and pressed, the diffusion of the liquid crystal material is accelerated to make the liquid crystal layer in the pixel region uniform so that the gap uniformity in the pixel region is maintained. . On the other hand, when the diffusion of the liquid crystal material is slow, the liquid crystal layer is thicker in the center of the pixel region than in the periphery of the pixel region (drum state), and gap uniformity is impaired.

  Next, in order to prevent misalignment of the bonded substrate during transport to the UV curing process, UV temporary curing is performed at several locations on the outer peripheral seal as a temporary fixing of the sealing material. At this time, the liquid crystal material diffuses in the pixel region over time and reaches the outer light shielding region, but in the present invention, the diffusion rate of the liquid crystal material in the light shielding region is reduced by the liquid repellent treatment layer, Do not touch the sealing material. In this state, in the next UV curing step, the sealing material is cured by a predetermined amount of UV irradiation. This liquid crystal diffusion control can prevent the uncured sealing material and the liquid crystal material from coming into contact with each other.

  Then, in the next thermosetting step, the sealing material is completely cured by heating at a predetermined temperature, and the required adhesive strength is obtained. Also at this time, since the diffusion of the liquid crystal material is continuously controlled by the liquid repellent treatment layer of the present invention, the liquid crystal material is not in contact with the sealing material. In this way, contact between the semi-cured sealing material and the liquid crystal material can be suppressed. The viscosity of the liquid crystal material gradually decreases with heating, and when the thermosetting is completed, the entire area inside the seal is diffused and filled, the seal material and the liquid crystal material come into contact with each other, and uniformity of the gap is ensured even in the vicinity of the frame BM. The Thereafter, the manufactured liquid crystal display panel is subjected to an ACF (Anisotropic Conductive Film) pasting / TCP (Tape Carrier Package) pressure welding process and a substrate pressure welding process, and a backlight light source is attached in an assembly process, thereby completing a liquid crystal display device.

  Thus, in the present invention, by disposing the liquid repellent treatment layer, the diffusion rate of the liquid crystal material passing through the light shielding region outside the pixel region is reduced, and the uncured or semi-cured sealing material and the liquid crystal material are reduced. Contact can be suppressed. Note that the liquid repellent layer may be formed outside the pixel region, and may be formed up to the seal application position when the adhesion between the sealant and the substrate can be secured. In addition, depending on the setting of the liquid repellent treatment layer, the orientation of the portion where the layer is disposed may be disturbed, and light leakage of the liquid crystal display panel may be a problem. Therefore, the liquid repellent treatment layer is preferably disposed only in the light shielding region. Moreover, although the example which has a space | interval between frame BM and a sealing material was shown in FIG. 1, frame BM can also be extended to a seal | sticker application position as needed.

[Embodiment 2]
FIG. 5 is a sectional view showing the structure in the vicinity of the frame of the liquid crystal display panel according to the second embodiment of the present invention. This liquid crystal display panel is the same as the liquid crystal display panel according to the first embodiment shown in FIG. 1, except that a fluororesin such as ethylene tetrafluoride is applied to desired positions on the surface of the frame BM and on the film surface of the TFT substrate facing it. The fluorine film 11a is formed as a thin film by coating or fluorination treatment.

  In this manner, the liquid repellent treatment layer as the fluorine film 11a is provided on the surface of the frame BM6 of the CF substrate 3 and on the film surface of the TFT substrate 2 facing the frame BM6, thereby providing liquid crystal repellency. As a result, the diffusion rate of the liquid crystal material 4 passing through the light shielding region can be reduced. Here, if the fluorine film 11a is formed with a thickness of 10 nm or more, the contact angle between the fluorine film 11a and the liquid crystal material 4 is not substantially changed. Therefore, the fluorine film 11a has a film thickness of 10 to 100 nm. It is confirmed that it should be formed. FIG. 6 shows a state when the liquid crystal material 4 is dropped in a matrix on the TFT substrate 2 on which a liquid repellent film such as the fluorine film 11a is formed between the pixel region and the seal application position (here, one drop). ).

[Embodiment 3]
FIG. 7 is a cross-sectional view showing the structure in the vicinity of the frame of the liquid crystal display panel according to the third embodiment of the present invention. This liquid crystal display panel is the same as the liquid crystal display panel of the first embodiment shown in FIG. 1, except that the silicone film is locally applied to the surface of the frame BM and the film surface of the TFT substrate facing the frame BM. 11b is formed as a thin film.

  In this way, the liquid-repellent treatment layer, which is the silicone film 11b, is provided on the surface of the frame BM6 of the CF substrate 3 and the film surface of the TFT substrate 2 facing the frame BM6, thereby providing liquid crystal repellency. As a result, an effect of reducing the diffusion speed of the liquid crystal material 4 passing through the light shielding region can be obtained. The silicone film 11b may be formed with a thickness of 10 to 100 nm.

  FIG. 8 conceptually shows the liquid crystal diffusion control effect by the liquid repellent treatment layer. FIG. 8B shows the diffusion state of the liquid crystal material when the substrates are bonded together. When the CF substrate 3 and the TFT substrate 2 are brought into contact with and pressed, the liquid crystal material 4 shields the frame BM from the pixel region. It spreads rapidly into the area. As a result, the diffused liquid crystal material 4 comes into contact with the uncured sealing material 5 before UV curing. On the other hand, FIG. 8A shows the diffusion state of the liquid crystal material when the substrates are bonded to each other according to the present invention. Even when the CF substrate 3 and the TFT substrate 2 are contacted / pressurized, the light shielding region is not exposed to the liquid crystal material 4. Since the liquid repellent treatment is performed to increase the contact angle, the diffusion speed of the liquid crystal material 4 is significantly reduced in the light shielding region. As a result, the timing at which the liquid crystal material 4 comes into contact with the uncured seal material 5 before UV curing can be delayed, and the contact between the uncured seal material 5 and the liquid crystal material 4 can be suppressed.

  If the contact angle is measured based on JIS R 3257 (1999) “Test method for wettability of glass substrate surface” using a liquid crystal material sealed in a liquid crystal display panel (for example, contact angle measurement manufactured by Kyowa Interface Science) Machine DM300), the degree of liquid repellency can be easily confirmed. This liquid repellency can be reproduced by disassembling the liquid crystal display panel and removing the liquid crystal material adhering with acetone or IPA and then measuring again as long as the liquid crystal repellent layer is formed. By forming the liquid repellent treatment layer, the surface energy of the liquid repellent treatment layer applied to the frame BM of the CF substrate and the film surface of the TFT substrate opposite to the frame BM is the surface energy on the alignment film surface in the pixel region. Lower than. This can be determined by measuring the contact angle of the liquid repellent layer and the contact angle on the alignment film surface of the pixel region. The contact angle of the liquid repellent layer to the liquid crystal material is determined by the alignment film of the pixel region. It becomes larger than the contact angle on the surface.

  FIG. 9 shows the relationship between the liquid crystal diffusion speed and the gap in the frame BM formation region of the liquid crystal display panel of the present invention. In general, in the liquid crystal display panel, the gap between the frame BM formation region, that is, the gap distance between the frame BM and the TFT substrate, is that the CF layer is not formed in the frame BM formation region. Larger) From FIG. 9, it can be seen that the liquid crystal diffusion rate gradually decreases as the gap distance between the frame BM and the TFT substrate decreases, that is, the gap in the pixel region decreases.

  However, if the liquid-repellent treatment is not performed on the light-shielding region (marked with x in the figure), there is a limit to speed reduction even if the gap distance between the frame BM and the TFT substrate is considerably shortened. Therefore, if the distance is shortened so that the frame BM and the TFT substrate come into contact with each other in order to further reduce the speed, there arises a problem that the frame BM and the TFT substrate partially come into contact. As a result, the gap uniformity deteriorates at the contact point in the vicinity of the frame BM, and a new problem of peripheral unevenness occurs. On the other hand, by forming a liquid repellent treatment layer such as a fluorine film or a silicone film as a thin film (Δ mark and □ mark in the figure), there is no need to extremely shorten the gap distance between the frame BM and the TFT substrate. It is possible to select the type of the liquid repellent treatment layer according to the gap of the target pixel region or the frame BM width of the liquid crystal display panel. As a result, the required liquid crystal diffusion speed can be obtained without deteriorating the gap uniformity in the vicinity of the frame BM.

  Note that the contact angle between the fluorine film or silicone film and the liquid crystal material is about 10 nm as described above, which is a substantially constant value, but here it is set to 100 nm in consideration of the occurrence rate of pinholes generated due to unpainted areas. Further, the width of the liquid repellent layer can be set within the allowable range of the frame BM width between the pixel region and the seal application position, and is set in consideration of the lead time from the bonding process out to the thermosetting process in. Good. For example, when manufacturing a liquid crystal display panel in which the distance between the frame BM and the TFT substrate is 2.0 μm under process conditions in which the lead time from the bonding process out to the thermosetting process in is within 2.5 minutes. 9, in the case where a liquid crystal repellent layer having a fluorine film is provided on the surface of the frame BM and on the film surface of the TFT substrate opposite thereto, the width of the liquid repellent layer is 4.5 mm or more in consideration of variation. good. If it does in this way, an uncured sealing material and a liquid crystal material will not contact.

  In the above embodiment, the description has been given by taking as an example a configuration in which both film surfaces of the CF substrate and the TFT substrate are subjected to liquid repellent treatment for controlling liquid crystal diffusion. However, at least one of the CF substrate and the TFT substrate is described. If the liquid crystal repellent treatment is applied to the liquid crystal, the diffusion rate of the liquid crystal material can be reduced, so that the time of contact between the uncured or semi-cured seal material and the liquid crystal material can be delayed, resulting in contamination of the liquid crystal material. Can be suppressed.

  In the following examples, specific examples of the method for producing a liquid crystal display panel of the present invention will be described. However, the present invention is not limited to the following examples unless the gist of the present invention is changed.

  First, as a first embodiment, a method for manufacturing a liquid crystal display device in the IPS mode when a fluorine film is used as the liquid repellent treatment layer will be described.

  In the liquid crystal repellent treatment process of the CF substrate, the surface of the frame BM between the pixel region and the seal application position was subjected to fluorination treatment. As this fluorination treatment, a fluorine film having a film thickness of about 100 nm was formed in a closed curve by locally depositing fluorine-based molecules with a film forming apparatus and then performing a polymerization treatment. In addition, in a liquid crystal display panel having a gap distance of 2.1 μm between the frame BM and the TFT substrate, it is necessary to produce fluorine under the process conditions in which the lead time from the bonding process out to the thermosetting process in is within 2 minutes. The film width was set to 4 mm (the target value of the gap (gap) in the pixel region was 2.0 μm). On the other hand, in the liquid crystal repellent treatment process of the TFT substrate, the same fluorination treatment was performed on the SiNx film surface of the TFT substrate between the pixel region facing the fluorine film of the CF substrate and the seal application position. In this way, a fluorine film having a film thickness of about 100 nm was formed in a closed curve shape with a width of 4 mm on the TFT substrate side as well as the CF substrate.

  Next, in the seal application process, a hybrid type (UV + thermosetting) sealant was applied in a closed curve shape as a peripheral (auxiliary) seal and a main seal at predetermined positions so as to surround the pixel region. Next, in the liquid crystal dropping step, the liquid crystal material was dropped in a matrix form at a predetermined drop amount at a predetermined position inside the main seal. Thereafter, in the bonding step, the two substrates were brought into contact with each other and pressed to uniformly diffuse the liquid crystal material throughout the pixel region between the substrates, thereby forming a uniform gap between the substrates. And in the case of conveyance to the next process, UV temporary hardening of some places was performed partially as temporary stop of a sealing material. In the next UV curing step, the sealing material was cured at a UV irradiation amount of 3000 mJ. At this time, it was confirmed that the uncured sealing material and the liquid crystal material were not in contact with each other by the fluorine film. Then, in the thermosetting step, the sealing material was completely cured by heating at 120 ° C. for 1 hour. At this time, it was confirmed that the semi-cured sealing material and the liquid crystal material were not in contact with each other at the start of heating. Thereafter, when the thermosetting of the sealing material was completed, the liquid crystal material was diffused and filled in the entire area inside the seal, the sealing material and the liquid crystal material were in contact with each other, and a gap was also formed in the vicinity of the frame BM. After the thermosetting was completed, a gap measurement in the vicinity of the pixel region and the frame BM of the liquid crystal display panel was performed. As a result, it was confirmed that a uniform gap was obtained over the entire pixel region.

  A high-temperature and high-humidity test of the liquid crystal display device according to the embodiment of the present invention thus manufactured was performed. As a result of carrying out a 1500 h drive test at a temperature of 60 ° C. and a humidity of 60%, the occurrence of spots, unevenness, and peeling of the seal in the periphery of the seal of the liquid crystal display panel was not confirmed, and a good display state was obtained. As a comparison, a liquid crystal display panel in which no liquid repellent treatment layer was formed was produced, but it was confirmed that spots were generated in the periphery of the seal when the driving test reached 1000 h.

  Next, as a second embodiment, a method of manufacturing a liquid crystal display device in the TN mode when a fluorine film is used as the liquid repellent treatment layer will be described.

  In the liquid crystal repellent treatment process of the CF substrate, the surface of the frame BM between the pixel region and the seal application position was subjected to fluorination treatment. As this fluorination treatment, a fluorine film having a film thickness of about 100 nm was formed in a closed curve by locally depositing fluorine-based molecules with a film forming apparatus and then performing a polymerization treatment. In addition, in a liquid crystal display panel with a gap distance between the frame BM and the TFT substrate of 2.3 μm, fluorine can be produced under the process conditions in which the lead time from the bonding process out to the thermosetting process in is within 2 minutes. The film width was set to 4.5 mm (the target value of the gap (gap) in the pixel region was 2.2 μm). On the other hand, in the liquid crystal repellent treatment process of the TFT substrate, the same fluorination treatment was performed on the SiNx film surface of the TFT substrate between the pixel region facing the fluorine film of the CF substrate and the seal application position. In this manner, a fluorine film having a film thickness of about 100 nm was formed in a closed curve with a width of 4.5 mm on the TFT substrate side in the same manner as the CF substrate.

  Next, in the seal application process, a hybrid type (UV + thermosetting) sealant was applied in a closed curve shape as a peripheral (auxiliary) seal and a main seal at predetermined positions so as to surround the pixel region. Next, in the Ag application step, Ag transfer was dropped in a matrix at predetermined positions outside the main seal. Next, in the liquid crystal dropping step, the liquid crystal material was applied to the predetermined position inside the main seal in the form of dots at a predetermined dropping amount. Thereafter, in the bonding step, the two substrates were brought into contact with each other and pressed to uniformly diffuse the liquid crystal material throughout the pixel region between the substrates, thereby forming a uniform gap between the substrates. And in the case of conveyance to the next process, UV temporary hardening of some places was performed partially as temporary stop of a sealing material. In the next UV curing step, the sealing material was cured at a UV irradiation amount of 3000 mJ. At this time, it was confirmed by the fluorine film that the uncured sealing material and the liquid crystal material were not in contact. Then, in the thermosetting step, the sealing material was completely cured by heating at 120 ° C. for 1 hour. At this time, it was confirmed that the semi-cured sealing material and the liquid crystal material were not in contact with each other by the fluorine film at the start of heating. Thereafter, when the thermosetting of the sealing material was completed, the liquid crystal material was diffused and filled in the entire area inside the seal, the sealing material and the liquid crystal material were in contact with each other, and a gap was also formed in the vicinity of the frame BM. After the thermosetting was completed, a gap measurement in the vicinity of the pixel region and the frame BM of the liquid crystal display panel was performed. As a result, it was confirmed that a uniform gap was obtained over the entire pixel region.

  A high-temperature and high-humidity test of the liquid crystal display device according to the embodiment of the present invention thus manufactured was performed. As a result of carrying out a 1500 h drive test at a temperature of 60 ° C. and a humidity of 60%, the occurrence of spots, unevenness, and peeling of the seal in the periphery of the seal of the liquid crystal display panel was not confirmed, and a good display state was obtained. As a comparison, a liquid crystal display panel in which the liquid repellent treatment layer was not formed was produced, but it was confirmed that spots and partial seal peeling occurred in the periphery of the seal when the driving test reached 1000 h.

  Next, as a third embodiment, a method for manufacturing a liquid crystal display device in the IPS mode when a silicone film is used as the liquid repellent treatment layer will be described.

  In the liquid crystal repellent treatment process of the CF substrate, the surface of the frame BM between the pixel region and the seal application position was subjected to silicone treatment to form a silicone film having a film thickness of about 100 nm in a closed curve shape. In addition, a liquid crystal display panel with a gap distance of 2.1 μm between the frame BM and the TFT substrate is manufactured in a process condition in which the lead time from the bonding process out to the thermosetting process in is within 2 minutes. The film width was set to 4 mm (the target value of the gap (gap) in the pixel region was 2.0 μm). On the other hand, in the liquid crystal repellent treatment process of the TFT substrate, the same silicone treatment was performed on the SiNx film surface of the TFT substrate between the pixel region facing the silicone film of the CF substrate and the seal application position. In this way, a silicone film having a film thickness of about 100 nm was formed on the TFT substrate side in a closed curve shape with a width of 4 mm, similarly to the CF substrate.

  Next, in the seal application process, a hybrid type (UV + thermosetting) sealant was applied in a closed curve shape as a peripheral (auxiliary) seal and a main seal at predetermined positions so as to surround the pixel region. Next, in the liquid crystal dropping step, the liquid crystal material was dropped in a matrix form at a predetermined drop amount at a predetermined position inside the main seal. Thereafter, in the bonding step, the two substrates were brought into contact with each other and pressed to uniformly diffuse the liquid crystal material throughout the pixel region between the substrates, thereby forming a uniform gap between the substrates. And in the case of conveyance to the next process, UV temporary hardening of some places was performed partially as temporary stop of a sealing material. In the next UV curing step, the sealing material was cured at a UV irradiation amount of 3000 mJ. At this time, it was confirmed by the silicone film that the uncured sealing material and the liquid crystal material were not in contact. Then, in the thermosetting step, the sealing material was completely cured by heating at 120 ° C. for 1 hour. At this time, it was confirmed that the semi-cured sealing material and the liquid crystal material were not in contact with each other by the silicone film at the start of heating. Thereafter, when the thermosetting of the sealing material was completed, the liquid crystal material was diffused and filled in the entire area inside the seal, the sealing material and the liquid crystal material were in contact with each other, and a gap was also formed in the vicinity of the frame BM. After the thermosetting was completed, a gap measurement in the vicinity of the pixel region and the frame BM of the liquid crystal display panel was performed. As a result, it was confirmed that a uniform gap was obtained over the entire pixel region.

  A high-temperature and high-humidity test of the liquid crystal display device according to the embodiment of the present invention thus manufactured was performed. As a result of carrying out a 1500 h drive test at a temperature of 60 ° C. and a humidity of 60%, the occurrence of spots, unevenness, and peeling of the seal in the periphery of the seal of the liquid crystal display panel was not confirmed, and a good display state was obtained. As a comparison, a liquid crystal display panel in which no liquid repellent treatment layer was formed was produced, but it was confirmed that spots were generated in the periphery of the seal when the driving test reached 1000 h.

  INDUSTRIAL APPLICABILITY The present invention can be used for a liquid crystal display panel that sandwiches liquid crystal between a pair of opposing substrates, a liquid crystal display device that uses the liquid crystal display panel, and a method for manufacturing the same.

It is sectional drawing which shows the structure of the frame vicinity of the liquid crystal display panel of 1st Embodiment of this invention. It is a top view of the liquid crystal display panel which shows the formation area of the liquid-repellent processing layer of this invention. It is a top view of the liquid crystal display panel which shows the formation area of the liquid-repellent processing layer of this invention. It is a flowchart which shows the manufacturing process of the liquid crystal display panel of this invention. It is sectional drawing which shows the structure of the frame vicinity of the liquid crystal display panel of 2nd Embodiment of this invention. It is a schematic diagram of the TFT substrate in which the liquid repellent treatment layer is formed between the pixel region of the present invention and the seal application position. It is sectional drawing which shows the structure of the frame vicinity of the liquid crystal display panel of 3rd Embodiment of this invention. It is a conceptual diagram which shows the liquid-crystal diffusion control effect by a liquid-repellent liquid processing layer, (a) has shown the liquid-crystal diffusion at the time of substrate bonding of this invention, (b) The liquid-crystal diffusion at the time of the conventional substrate bonding. It is a figure which shows the correlation with the liquid-crystal diffusion speed in a frame BM formation part, and a gap. It is sectional drawing which shows the structure of the frame vicinity of the conventional liquid crystal display panel. It is a flowchart which shows the manufacturing process of the conventional liquid crystal display panel. It is sectional drawing which shows the other structure of the frame vicinity of the conventional liquid crystal display panel. It is sectional drawing which shows the other structure of the conventional liquid crystal display panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 2 TFT substrate 3 CF substrate 4 Liquid crystal material 5 Seal material 6 Frame BM
7 Color layer 8 Drive circuit layer 9 Alignment film 10 Column spacer 10a Spherical spacer 11 Liquid repellent treatment layer 11a Fluorine coating 11b Silicone coating 12 Protrusion 13 Flow control wall

Claims (5)

A liquid crystal material is provided between a first substrate in which a black matrix is formed in a light shielding region of a frame and a second substrate in which an organic film or an inorganic film is formed in the light shielding region, and the light shielding of at least one substrate In the liquid crystal display panel in which the liquid crystal material is sealed by a sealing material provided outside the region,
The liquid crystal display panel drops the liquid crystal material in a region surrounded by the sealing material, bonds the first substrate and the second substrate, and then cures the sealing material to form the liquid crystal material. Is manufactured by sealing,
A gap between the black matrix of the first substrate of the frame and the second substrate is 2.0 μm;
A liquid repellent treatment layer for repelling the liquid crystal material on at least a part of the black matrix of the first substrate and / or the organic film or the inorganic film of the second substrate; The liquid crystal treatment layer is a fluorine film or a silicone film, and has a thickness of 10 to 100 nm and a width of 4.5 mm or more.
A liquid crystal display panel, wherein a contact angle of the first substrate and / or the second substrate with respect to the liquid crystal material in the light shielding region is larger than a contact angle with a pixel region inside the light shielding region. A first substrate in which a black matrix is formed in a light shielding region of a frame and a second substrate in which an organic film or an inorganic film is formed in the light shielding region are formed, and a sealing material is formed outside the light shielding region of one of the substrates. The liquid crystal material is dropped onto the region surrounded by the sealing material, and the first substrate and the second substrate are bonded together, and then the sealing material is cured to seal the liquid crystal material. In the liquid crystal display panel manufacturing method,
A liquid repellent treatment for repelling the liquid crystal material on at least a part of the light shielding region of the one substrate before dropping the liquid crystal material and / or the other substrate before being bonded to the one substrate. And increasing the contact angle of the one substrate and / or the other substrate with respect to the liquid crystal material in the light shielding region,
A gap between the black matrix of the first substrate of the frame and the second substrate is 2.0 μm;
A method for producing a liquid crystal display panel, wherein the liquid repellent treatment layer formed by the liquid repellent treatment is a fluorine film or a silicone film, and has a thickness of 10 to 100 nm and a width of 4.5 mm or more. A first substrate having a black matrix formed in a light shielding region of a frame and a second substrate having an organic film or an inorganic film formed in the light shielding region are formed, outside the light shielding region of the second substrate. A sealing material is applied, a liquid crystal material is dropped onto a region surrounded by the sealing material, the second substrate and the first substrate are bonded together, the sealing material is cured, and the first material is cured. In the method of manufacturing a liquid crystal display panel in which the liquid crystal material is sealed between the substrate and the second substrate,
At least one on the organic film or the inorganic film of the second substrate before dropping the liquid crystal material and / or on the black matrix of the first substrate before being bonded to the second substrate. Part is subjected to a liquid repellent treatment to repel the liquid crystal material to increase a contact angle of the first substrate and / or the second substrate with respect to the liquid crystal material in the light shielding region,
A gap between the black matrix of the first substrate of the frame and the second substrate is 2.0 μm;
A method for producing a liquid crystal display panel, wherein the liquid repellent treatment layer formed by the liquid repellent treatment is a fluorine film or a silicone film, and has a thickness of 10 to 100 nm and a width of 4.5 mm or more. The method for producing a liquid crystal display panel according to claim 2, wherein the liquid repellent treatment includes fluorination treatment or silicone treatment. The region to be subjected to the liquid repellent treatment is defined as a time from when the two substrates are bonded to when the sealing material is cured, and a diffusion rate of the liquid crystal material determined based on the contact angle and the gap between the substrates. The liquid crystal display panel manufacturing method according to claim 2, wherein the liquid crystal display panel is set with reference to the liquid crystal display panel.

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