JP7340480B2 - liquid crystal display element - Google Patents

Description

The present invention relates to a liquid crystal display element that is widely used as a display function in various electronic devices.

FIG. 5 is a diagram showing a conventional liquid crystal display element, in which (a) is a top view and (b) is a side sectional view. The liquid crystal display element in FIG. 5 shows a state in which liquid crystal is not injected and is not sealed.

The liquid crystal display element 51 has a structure in which an upper substrate 52 having an electrode 54 and an alignment film 55 formed on its surface, and a lower substrate 53 having an electrode 54 and an alignment film 55 formed on its surface are bonded together with a sealing material 56. The electrode 54 is specifically formed of a transparent conductive film (ITO film). Further, the alignment film 55 is a functional film for aligning a group of liquid crystal molecules in a certain direction, and is formed of, for example, a polyimide film or the like.

The upper substrate 52 and the lower substrate 53 are bonded together with a gap 57 corresponding to the thickness of the sealing material 56, and the sealing material 56 covers the periphery where the upper substrate 52 and the lower substrate 53 are overlapped. It is surrounded by a seal. A liquid crystal injection port 58 for injecting liquid crystal is provided in a part of this sealing material 56. Further, the liquid crystal injection port 58 is generally arranged at a position where the end surfaces of the upper substrate 52 and the lower substrate 53 are on the same line.

The materials of the upper substrates 52 and 53 vary depending on the liquid crystal driving method and whether the liquid crystal display element is a transmissive type or a reflective type, but one is a transparent glass substrate and the other is either a silicon substrate or a transparent glass substrate. It is common to have a configuration. Furthermore, plastic substrates have recently come to be used as substrate materials in more liquid crystal display elements.

FIG. 6 is a diagram showing a process of injecting liquid crystal into a liquid crystal display element, and is a side view showing the positional relationship among the liquid crystal display element, a liquid crystal dish, and the liquid crystal arranged on the liquid crystal dish.

In the step of injecting liquid crystal, first, the liquid crystal display element 51 is held in a position with the liquid crystal injection port 58 facing downward, and then placed in a vacuum chamber (not shown) together with the liquid crystal dish 61 containing the liquid crystal 60. Thereafter, the inside of the chamber is evacuated to a predetermined pressure, and the liquid crystal 60 in the liquid crystal dish 61 containing the liquid crystal 60 is brought into contact with the liquid crystal injection port 58 of the liquid crystal display element 51. In this state, the liquid crystal 60 is injected using the pressure difference between the inside of the vacuum chamber and the inside of the liquid crystal display element 51, which is generated by returning the inside of the vacuum chamber to the atmosphere.

Thereafter, although not shown, the liquid crystal injection port 58 is sealed with a sealing material to complete the liquid crystal display element 51. As the sealing material, a thermosetting resin or an ultraviolet curable resin is appropriately selected and used.

The liquid crystal display element 51 shown in FIG. 5 has a general structure in which the liquid crystal injection port 58 is located at a position where the end surfaces of two substrates (upper substrate 52, lower substrate 53) are on the same line. However, this is not limited to cases in which the liquid crystal injection port is placed in a stepped area that occurs when two substrates are bonded together in a misaligned position in order to maximize the display area and layout of the final product. There is also.

FIG. 7 is a top view showing a conventional liquid crystal display element. Each member constituting the liquid crystal display element in FIG. 7 is the same as the liquid crystal display element 51 shown in FIG. 5, but the position of the liquid crystal injection port 58 is different, and the formation pattern of the sealing material 56 is different. It is. The upper substrate 52 and the lower substrate 53 are substrates of the same size, but are bonded together with the upper substrate 52 positioned above being shifted to the left with respect to the lower substrate 53 positioned below. This forms a stepped portion 59, and a liquid crystal injection port 58 is provided at the position of this stepped portion 59.

FIG. 8 is a diagram showing a step of injecting liquid crystal into the liquid crystal display element shown in FIG. 7, and is a side view showing the positional relationship among the liquid crystal display element, the liquid crystal dish, and the liquid crystal disposed on the liquid crystal dish.

In the step of injecting the liquid crystal, as shown in FIG. 8, the liquid crystal display element 51 is held in a position with the liquid crystal injection port 58 facing downward, and then placed in a vacuum chamber ( (not shown). Thereafter, the inside of the chamber is evacuated to a predetermined pressure, and the liquid crystal 60 in the liquid crystal dish 61 containing the liquid crystal 60 is brought into contact with the liquid crystal injection port 58 of the liquid crystal display element. In this state, liquid crystal is injected using the pressure difference between the inside of the vacuum chamber and the inside of the liquid crystal display element 51, which is generated by returning the inside of the vacuum chamber to the atmosphere.

Thereafter, although not shown, the liquid crystal injection port 58 is sealed with a sealing material to complete the liquid crystal display element 51. As the sealing material, a thermosetting resin or an ultraviolet curable resin is appropriately selected and used.

JP 7-209658

In the case of the liquid crystal display element 51 configured as shown in FIG. Due to the distance to the inlet 58, the liquid crystal 60 escapes in the direction of the arrow in the figure, making it impossible to properly inject the liquid crystal into the liquid crystal inlet 58, resulting in defects such as liquid crystal not being injected. .

The present invention attempts to solve the above-mentioned problems, and aims to provide a liquid crystal display element that can accurately inject liquid crystal even if there is a certain distance to the liquid crystal injection port. .

A liquid crystal display element in which liquid crystal is injected through a liquid crystal injection port formed by bonding the peripheral edges of two substrates together with a sealing material and opening a part of the sealing material, the liquid crystal injection port being The liquid crystal display is provided on a stepped portion formed by bonding two substrates with opposite side portions in a shifted positional relationship, and the liquid crystal is provided on the surface of the overhanging portion of one substrate that overhangs the stepped portion. A liquid crystal display element is provided with a liquid crystal injection path for guiding liquid crystal into an injection port.
The width of the liquid crystal injection path is the same as or narrower than the width of the liquid crystal injection port, and the liquid crystal injection path may be arranged to face each other.
The liquid crystal injection path may be formed by patterning a thin film on the surface of the protrusion of the substrate.
The thin film may be formed of an electrode film and/or an alignment film formed on the substrate.
Further, the liquid crystal injection path may be formed by etching or laser processing a part of the surface of the protruding portion of the substrate.
The liquid crystal injection path may be formed of two narrow grooves that extend continuously from two open ends of the sealing material constituting the liquid crystal injection port to an end of the substrate.

According to the present invention, since the liquid crystal does not wet and spread outside the vicinity of the liquid crystal injection port, the liquid crystal is efficiently and accurately injected from the liquid crystal injection port, and defects such as non-injection are prevented from occurring.

FIG. 1 is a diagram showing a liquid crystal display element in an embodiment of the present invention. FIG. 3 is a process diagram showing a step of injecting liquid crystal into a liquid crystal display element in an embodiment of the present invention. FIG. 7 is a diagram showing a liquid crystal display element in another embodiment of the present invention. FIG. 7 is a diagram showing a liquid crystal display element in another embodiment of the present invention. FIG. 1 is a diagram showing a conventional liquid crystal display element. FIG. 3 is a diagram showing a process of injecting liquid crystal into a conventional liquid crystal display element. FIG. 1 is a top view showing a conventional liquid crystal display element. 8 is a diagram showing a process of injecting liquid crystal into the liquid crystal display element shown in FIG. 7. FIG.

Hereinafter, a liquid crystal display element according to an embodiment of the present invention will be described.
FIG. 1 is a diagram showing a liquid crystal display element according to an embodiment of the present invention, in which (a) is a top view, (b) is a sectional view taken along line AA in (a), and (c) is a right side view in (a). It is a diagram.

The liquid crystal display element 1 is made up of an upper substrate 2 and a lower substrate 3 that are bonded together, and are bonded to each other while maintaining a gap in which liquid crystal is filled. An electrode 4 is formed on each opposing surface where the upper substrate 2 and lower substrate 3 are bonded together, and an alignment film 5 is laminated above the electrode 4.

The electrodes 4, 4 are specifically formed of a transparent conductive film (ITO film), and are formed using a film forming method such as vapor deposition. Further, the alignment films 5, 5 are functional films for aligning a group of liquid crystal molecules in a certain direction, and are formed of, for example, a polyimide film or the like.

A sealing material 6 is arranged so as to surround a display area (not shown) located at the center of the liquid crystal display element 1, and joins the upper substrate 2 and the lower substrate 3 while maintaining a constant gap. The gap surrounded by the sealing material 6 becomes a space into which liquid crystal is injected, and the liquid crystal is injected from an opening (hereinafter referred to as liquid crystal injection port 7) provided between the convex portions 6a, 6a of the sealing material 6. be done.

Since the above-mentioned upper substrate 2 and lower substrate 3 are pasted together in a positional relationship that is shifted from each other, a stepped portion 8 is created, and a portion of the lower substrate 3 protrudes outward from this stepped portion 8, resulting in A portion 8a is now formed. A liquid crystal injection port 7 formed of the sealing material 6 is disposed toward the stepped portion 8 side.

An electrode 4 and an alignment film 5 formed on the lower substrate 3 are disposed on the surface of the overhanging portion 8a, and the electrode 4 and alignment film 5 are disposed on a portion facing the liquid crystal injection port 7. The electrode 4 and the alignment film 5 are not formed so as to match the width of the liquid crystal injection port 7 and have substantially the same width up to the outer edge of the lower substrate 3. As a result, a liquid crystal injection path 9 for guiding liquid crystal is formed in a portion extending from the outer end of the lower substrate 3 to the liquid crystal injection port 7. In this embodiment, the width of the liquid crystal injection path 9 is made to match the width of the liquid crystal injection port 7, but it is also possible to make the width narrower than this. Guidance of the liquid crystal to the inlet 7 is ensured.

The method for forming the liquid crystal injection path 9 is facilitated by performing a patterning process so that the electrode 4 and the alignment film 5 are not formed in the area forming the liquid crystal injection path 9 when forming the electrode 4 and the alignment film 5. can be formed into Further, even after forming the electrodes 4 and the alignment film 5 on the entire surface of the overhanging portion 8a, a method may be used in which the electrodes 4 and the alignment film 5 are removed at the portion corresponding to the liquid crystal injection path 9.

The liquid crystal injection path 9 has a concave portion formed by the thickness of the electrode 4 and the alignment film 5 on the surface of the projecting portion 8a at a portion where the electrode 4 and the alignment film 5 are not formed. As a result, the liquid crystal does not leak outward and is reliably guided toward the liquid crystal injection port 7 along the concave portion, so that the liquid crystal can be injected accurately. By accurately injecting liquid crystal, there is no need to waste liquid crystal, and there is no need to remove liquid crystal that has spread.

Although a two-layer structure has been described in which the electrode 4 and the alignment film 5 are formed on the surface of the projecting portion 8a, for example, the structure may be composed of only the electrode 4 without the alignment film 5. Furthermore, it is also possible to select a film made of a different material from either the electrode 4 or the alignment film 5.

FIG. 2 is a process diagram showing a process of injecting liquid crystal into a liquid crystal display element in an embodiment of the present invention. 10 is a liquid crystal, and 11 is a liquid crystal dish on which the liquid crystal 10 is placed.
When injecting the liquid crystal 10 into the liquid crystal display element 1, the liquid crystal display element 1 is placed facing the liquid crystal 10 in the liquid crystal pan 11 with the liquid crystal display element 1 upright so that the liquid crystal injection path 9 is on the lower side, and placed in a vacuum chamber (not shown). put in.

Thereafter, the inside of the chamber is evacuated to a predetermined pressure, and the liquid crystal 10 in the liquid crystal dish 11 containing the liquid crystal 10 is brought into contact with the liquid crystal injection path 9 of the liquid crystal display element 1. In this state, liquid crystal is injected using the pressure difference between the inside of the vacuum chamber and the inside of the liquid crystal display element 1, which is created by returning the inside of the vacuum chamber to the atmosphere.

At this time, the liquid crystal 10 is accurately injected into the liquid crystal display element 1 from the liquid crystal injection port 7 located between the convex portions 6a, 6a of the sealing material 6 along the liquid crystal injection path 9. Since the liquid crystal injection path 9 has a thickness difference between the electrode 4 and the alignment film 5 as described above, the liquid crystal 10 propagates linearly within the liquid crystal injection path 9 and is efficiently guided in the direction of the arrow in the figure. It flows into the liquid crystal display element 1 from the liquid crystal injection port 7 and is accurately injected. Subsequently, although not shown, the liquid crystal injection port 7 is sealed with a sealing material (thermosetting resin, ultraviolet curing resin, etc.) to complete the liquid crystal display element 1.

FIG. 3 is a diagram showing a liquid crystal display element according to another embodiment of the present invention, in which (a) is a top view, (b) is a sectional view taken along line AA in (a), and (c) is a right side view in (a). It is a front view.

The liquid crystal display element 21 is made up of an upper substrate 22 and a lower substrate 23 that are bonded together, and each is bonded to each other with a gap filled with liquid crystal maintained. Electrodes 24 are formed on opposing surfaces of the upper substrate 22 and the lower substrate 23 to which they are bonded together, and an alignment film 25 is laminated above them. The electrodes 24, 24 are specifically made of transparent conductive films (ITO films), and are formed using a film forming method such as vapor deposition. Further, the alignment films 25, 25 are functional films for aligning a group of liquid crystal molecules in a certain direction, and are formed of, for example, a polyimide film or the like.

A sealing material 26 is arranged so as to surround a display area (not shown) located at the center of the liquid crystal display element 21, and joins the upper substrate 22 and the lower substrate 23 while maintaining a constant gap. The gap surrounded by the sealing material 26 is a space into which liquid crystal is injected, and the liquid crystal is injected from an opening (hereinafter referred to as liquid crystal injection port 27) provided between the convex portions 26a, 26a of the sealing material 26. be done.

The above-mentioned substrate 22 and lower substrate 23 are attached to each other in a positional relationship that is shifted from each other, so a stepped portion 28 is created, and a portion of the lower substrate 23 protrudes outward from this stepped portion 28, thereby creating an overhanging portion. 28a is now formed. The liquid crystal injection port 27 formed of the sealing material 26 is disposed toward the stepped portion 28 side.

Unlike the liquid crystal display element of the embodiment shown in FIG. 1, the electrode 24 and the alignment film 25 formed on the lower substrate 23 are not disposed on the surface of the projecting portion 28a. However, although not shown, a terminal for connecting the electrode 24 and an external substrate (not shown) is provided on a small portion of the surface of the projecting portion 28a.

A liquid crystal injection path 29 is formed in a portion of the projecting portion 28a facing the liquid crystal injection port 27 to match the width of the liquid crystal injection port 27 and to have substantially the same width as the outer end of the lower substrate 23. The liquid crystal injection path 29 has a groove-like cross section, which allows the liquid crystal to be guided from the outer end of the lower substrate 23 to the liquid crystal injection port 27. The width of the liquid crystal injection path 29 can be configured to be narrower than the width of the liquid crystal injection port 27, and with this configuration, the liquid crystal can be reliably guided to the liquid crystal injection port 7.

The liquid crystal injection path 29 can be easily formed by etching, for example, since the material of the lower substrate 23 is usually silicon or glass. It is also possible to employ laser processing using a laser.

The liquid crystal injection path 29 has a concave groove shape extending from the liquid crystal injection port 27 toward the outer end of the lower substrate 23 on the surface of the protruding portion 28 a of the lower substrate 23 . As a result, when liquid crystal is injected, the liquid crystal does not leak outward and is reliably guided toward the liquid crystal inlet 27 along the groove of the liquid crystal injection path 29, so that the liquid crystal can be injected accurately. The liquid crystal injection method is the same as that described with reference to FIG. 2, so detailed explanation will be omitted.

FIG. 4 is a diagram showing a liquid crystal display element according to another embodiment of the present invention, in which (a) is a top view, (b) is a sectional view taken along line AA in (a), and (c) is a right side view in (a). It is a front view.

The liquid crystal display element 31 is made up of an upper substrate 32 and a lower substrate 33 bonded together, each bonded to maintain a gap filled with liquid crystal. Electrodes 34 are formed on opposing surfaces of the upper substrate 32 and the lower substrate 33 to which they are bonded together, and an alignment film 35 is laminated above them. The electrode 34 is specifically composed of a transparent conductive film (ITO film), and is formed using a film forming method such as vapor deposition. Further, the alignment film 35 is a functional film for aligning a group of liquid crystal molecules in a certain direction, and is formed of, for example, a polyimide film or the like.

A sealing material 36 is arranged to surround a display area (not shown) located at the center of the liquid crystal display element 31, and joins the upper substrate 32 and the lower substrate 33 with a constant gap maintained therebetween. The gap surrounded by the sealing material 36 is a space into which liquid crystal is injected, and the liquid crystal is injected from an opening (hereinafter referred to as liquid crystal injection port 37) provided between the convex portions 36a, 36a of the sealing material 36. be done.

The above-mentioned substrate 32 and lower substrate 33 are attached to each other in a positional relationship that is shifted from each other, so a stepped portion 38 is created, and a portion of the lower substrate 33 protrudes outward from this stepped portion 38, thereby creating an overhanging portion. 38a is now formed. A liquid crystal injection port 37 formed of the sealing material 36 is disposed toward the stepped portion 38 side.

The electrode 34 and the alignment film 35 formed on the lower substrate 33 are not provided on the surface of the protruding portion 38a. However, although not shown, a terminal for connecting the electrode 34 and an external substrate (not shown) is provided on a small portion of the surface of the projecting portion 38a. The overall configuration of the liquid crystal display element 31 described above is the same as that of the liquid crystal display element 21 of the embodiment shown in FIG.

Two narrow grooves 39, 39 are formed on the surface of the protruding portion 38a to match the width of the liquid crystal injection port 37 defined by the opening between the convex portions 36a, 36a of the sealing material 36. This narrow groove 39 is provided to extend from the respective ends of the convex portions 36a, 36a of the sealing material 36 to the outer end of the lower substrate 33, and is connected to the two narrow grooves 39, 39. A liquid crystal injection path 40 is formed at the surface of the protruding portion 38a sandwiched between the two.

The narrow grooves 39 can be easily formed by, for example, etching, since the material of the lower substrate 33 is usually silicon or glass. Moreover, it is also possible to form by employing laser processing using a laser.

As mentioned above, by providing the narrow grooves 39, 39, surface tension can be applied to the liquid crystal injection path 40 sandwiched between the narrow grooves 39, 39. leakage can be controlled. Therefore, liquid crystal injection can be performed accurately.
The liquid crystal injection method is the same as that described with reference to FIG. 2, so detailed explanation will be omitted.

1 Liquid crystal display element 2 Upper substrate 3 Lower substrate 4 Electrode 5 Alignment film 6 Seal material 6a Convex portion 7 Liquid crystal injection port 8 Step portion 8a Overhang portion 9 Liquid crystal injection path 10 Liquid crystal 11 Liquid crystal dish 21 Liquid crystal display element 22 Upper substrate 23 Lower substrate 24 Electrode 25 Alignment film 26 Seal material 26a Convex portion 27 Liquid crystal injection port 28 Step portion 28a Overhang portion 29 Liquid crystal injection path 31 Liquid crystal display element 32 Upper substrate 33 Lower substrate 34 Electrode 35 Alignment film 36 Seal material 36a Convex portion 37 Liquid crystal injection port 38 Stepped portion 38a Overhanging portion 39 Narrow groove 40 Liquid crystal injection path 51 Liquid crystal display element 52 Upper substrate 53 Lower substrate 54 Electrode 55 Alignment film 56 Seal material 57 Gap 58 Liquid crystal injection port 59 Stepped portion 60 Liquid crystal 61 Liquid crystal dish

Claims (1)

A liquid crystal display element in which liquid crystal is injected through a liquid crystal injection port formed by bonding the peripheral edges of two substrates together with a sealing material and opening a part of the sealing material, the liquid crystal injection port being The liquid crystal display is provided on a stepped portion formed by bonding two substrates with opposite side portions in a shifted positional relationship, and the liquid crystal is provided on the surface of the overhanging portion of one substrate that overhangs the stepped portion. A liquid crystal injection path is provided for guiding and injecting liquid crystal toward the injection port, and the liquid crystal injection path is continuous from each of the two open ends of the sealing material constituting the liquid crystal injection port to the end of the substrate. A liquid crystal display element comprising a surface of the protruding portion of the substrate sandwiched between two grooves extending as shown in FIG .

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