TWI464536B - Photosensitive monomer for liquid crystal layer or alignment layer, liquid crystal panel and manufacturing method thereof manufactured using the same - Google Patents

Description

Photosensitive monomer for liquid crystal layer or alignment layer, liquid crystal display panel using same and manufacturing method thereof

The present invention relates to a photosensitive monomer for a liquid crystal layer or an alignment layer, a liquid crystal display panel using the same, and a method for fabricating the same, and more particularly to a liquid crystal display panel using a photosensitive monomer assisted alignment technique and a method of fabricating the same

With the continuous advancement of display technology, all devices are developing toward small size, thin thickness, and light weight. Therefore, mainstream display devices on the market have been developed into liquid crystal display devices from conventional cathode ray tubes. In particular, liquid crystal display devices are widely used in various fields, such as mobile phones, notebook computers, video cameras, cameras, music players, mobile navigation devices, televisions, and the like, which are used in daily life, and display panels are often used in liquid crystal display panels. .

Among them, the brightness, contrast, color, and viewing angle of the liquid crystal display panel are the main parameters determining the viewing effect of the liquid crystal display device. With the development of liquid crystal display devices, currently mainstream or developing panels can be distinguished as: twisted nematic (TN), vertical alignment (VA), planar alignment (IPS) and other modes.

In the vertical alignment type (VA) liquid crystal panel technology, Multi-domain Vertical Alignment (MVA) was first developed, which is provided with a bump on the side of the color filter to make the liquid crystal molecules stand still. The vertical type is biased toward a specific angle; therefore, when a voltage is applied, the liquid crystal molecules change to a horizontal speed faster, and at the same time, the bumps can change the alignment of the liquid crystal molecules, thereby achieving a wide viewing angle effect. In addition to MVA In addition to technology, Polymer-Stabilizing Alignment (PSA) has been developed, which uses a microstructured polymer layer to replace the bumps in the MVA technology, and achieves a wide viewing angle and a fast reaction speed. Accordingly, at present, high-order liquid crystal display devices use vertical alignment type liquid crystal panel technology.

SUMMARY OF THE INVENTION The main object of the present invention is to provide a photosensitive monomer for a liquid crystal layer or an alignment layer, wherein the photosensitive monomer can form an alignment film having a protrusion of a nanometer size to help the liquid crystal molecules to have a stable alignment.

Another object of the present invention is to provide a liquid crystal display panel in which an alignment film formed of a photosensitive monomer has a nanometer size, so that the reaction speed, optical transmittance, and contrast of the liquid crystal layer can be greatly improved.

Still another object of the present invention is to provide a method of fabricating a liquid crystal display panel which can be applied to existing processes and devices, and which shortens the process time of the liquid crystal display panel and enhances its optical characteristics.

In order to achieve the above object, the photosensitive monomer for a liquid crystal layer or an alignment layer of the present invention is represented by the following formula (I): Wherein; each R ₁ and R ₂ are each independently a halogen atom based, nitro, cyano, C _1-12 alkyl, or at least one hydrogen atom is substituted with a halogen atom of C _1-12 alkyl group; and a is 1 -4, and b is 0-4.

In the photosensitive monomer for a liquid crystal layer or an alignment layer of the present invention, when used in combination with a photoinitiator, the photosensitive monomer can be polymerized by irradiation. In addition, since the polymer film formed after the polymerization has nano-scale protrusions, it can help the alignment effect of the liquid crystal molecules, and improve the reaction speed, optical transmittance and contrast of the liquid crystal layer. In particular, as shown in the above formula (I), the photosensitive monomer provided by the present invention has a main chain having a structure similar to that of a nematic liquid crystal molecule, and has only a side chain modification; therefore, the photosensitivity of the present invention When the monomer is doped into the liquid crystal molecules, in addition to forming a polymer film having an alignment effect, the solubility of the liquid crystal molecules can be improved. According to this, when the liquid crystal panel is produced, the liquid crystal molecules can be uniformly dispersed, and a liquid crystal layer having high optical uniformity can be produced. In addition, since the photosensitive monomer of the present invention has a similar structure to the nematic liquid crystal molecules, the photosensitive monomer can be formed into a plurality of types of nano-sized protrusions on the substrate under the same illumination process. These various types of protrusions and liquid crystal molecules will produce different molecular forces. Therefore, the photosensitive monomer of the present invention can be applied to existing machine equipment to adjust the mobility of the liquid crystal display required by the customer.

In the photosensitive monomer of the present invention, the formula (I) can be represented by the following formula (I-1) to formula (I-48):

Wherein each of R ₁ and R ₂ may each independently be a halogen atom, a nitro group, a cyano group, C _1-12 alkyl, or at least one hydrogen atom is substituted with a halogen atom of C _1-12 alkyl. Here, the term "halogen atom" means a fluorine, chlorine, bromine or iodine atom; and the term "alkyl" may mean a straight or branched alkyl group. Preferably, each of R ₁ and R ₂ may be independently from fluorine, chlorine, nitro, cyano, C _1-6 alkyl, or trifluoromethyl. More preferably, each of R ₁ and R ₂ is independently fluorine or C _1-3 alkyl, a is 1-2, and b is 0-2.

In the present invention, specific examples of the photosensitive monomer represented by the formula (I) may be the following formula (II), formula (III), or formula (IV), but the invention is not limited thereto:

Further, the photosensitive monomer of the formula (I) provided by the present invention, which is obtained by polymerization, is represented by the following formula (V): Wherein R ₁ , R ₂ , a and b are as defined above, and the number of n is not particularly limited and may be an integer of from 100 to 10,000.

The present invention further provides a method for fabricating a liquid crystal display panel using the photosensitive monomer, comprising: providing a first substrate and a second substrate, wherein the first substrate and the second substrate are respectively provided with a first An electrode and a second electrode, wherein the first electrode and the second electrode are disposed opposite to each other; and a liquid crystal material is injected between the first substrate and the second substrate, and the liquid crystal material comprises: a liquid crystal molecule, and a formula (I) a photosensitive monomer is shown; and an energy is applied to polymerize the photosensitive monomer to form a polymer film on at least one of the first substrate and the second substrate to serve as an alignment film.

In the method for fabricating the liquid crystal display panel of the present invention, by adding a photosensitive monomer to the liquid crystal material, the photosensitive monomer can be polymerized in the process of applying energy, and an alignment function is formed on the substrate. The polymer film, that is, an alignment film. In addition, in the method of fabricating the liquid crystal display panel of the present invention, the energy is preferably a light source, and more preferably an ultraviolet light source. When a photosensitive monomer is polymerized using a light source, it can be polymerized in combination with a photoinitiator known in the art. In addition to the light source, a voltage can be applied during the polymerization.

Therefore, the present invention further provides a liquid crystal display panel obtained by using the above method, comprising: a first substrate having a first electrode disposed thereon; and a second substrate having a second portion disposed thereon An electrode, wherein the first electrode is disposed opposite to the second electrode; an alignment film is formed on at least one of the first electrode and the second electrode; and a liquid crystal layer is disposed between the first substrate and the second substrate And the liquid crystal layer comprises a liquid crystal molecule; wherein the alignment film is a polymer film obtained by polymerizing a photosensitive monomer represented by the formula (I).

Here, the alignment film formed by using the photosensitive monomer of the formula (I) has a protrusion of a nano structure, so that the liquid crystal molecules can be stably aligned. In the present invention, the protrusion of the nanostructure refers to a protrusion having a length, a width and a height of from 1 to 500 nm; preferably a protrusion having a length, a width and a height of from 1 to 200 nm.

In the liquid crystal display panel of the present invention and the manufacturing method thereof, the photosensitive single system is as defined above, and thus will not be described herein.

Since the photosensitive monomer of the present invention can be used not only in combination with liquid crystal molecules, but also in combination with a material of an alignment layer (i.e., polyimide). Therefore, in the method of fabricating the liquid crystal display panel of the present invention, before the injecting the liquid crystal material, the method further includes: forming a first alignment layer on the first electrode or forming a second alignment layer on the second electrode, and One alignment layer or second Each of the layers is independently a polyammonium layer or a polymer layer synthesized by copolymerization of a sulfoxide monomer and a photosensitive monomer represented by the formula (I). The liquid crystal display panel obtained by the above method may further include: at least one of a first alignment layer disposed on the first electrode and a second alignment layer disposed on the second electrode, and the first alignment layer And the second alignment layer is each independently a polyammonium layer or a polymer layer synthesized by copolymerization of a sulfoxide monomer and a photosensitive monomer represented by the formula (I).

In more detail, in the liquid crystal display panel of the present invention, at least one side of the first substrate and the second substrate may further comprise an alignment layer of a polyammonium layer in the art. Alternatively, when the alignment film monomer material (ie, imide) is used in combination with the photosensitive monomer represented by the formula (I), at least one side of the first substrate and the second substrate of the liquid crystal display panel, Further, a polymer layer synthesized by copolymerization of a sulfhydryl monomer and a photosensitive monomer represented by the formula (I) may be further included as an alignment layer.

In addition, the photosensitive monomer represented by the formula (I) provided by the present invention can be applied to various liquid crystal display panel driving modes, such as a polymer stable vertical alignment mode (PS-VA) and a planar control mode ( IPS/FFS), or twisted nematic mode (TN), etc., but the present invention is not limited thereto.

In addition, the present invention further provides a liquid crystal display device including the aforementioned liquid crystal display panel. Here, the liquid crystal display device may be a display device such as a mobile phone, a notebook computer, a video camera, a camera, a music player, a mobile navigation device, a television, etc., but the present invention is not limited thereto.

The embodiments of the present invention are described below by way of specific examples, and those skilled in the art can readily appreciate the other advantages and advantages of the present invention. In addition, the present invention may be embodied or modified by various other embodiments without departing from the spirit and scope of the invention.

Examples 1 and 2 - Preparation of photosensitive monomers of formula (II) and (III) (i.e., M1 and M2 in Scheme I)

(II) (ie M1 in Flowchart I)

(III) (ie M2 in Flowchart I)

1-1. Synthesis of 4-(dodo-phenoxy)-tert-butyl-dimethyl silane) (30a)

Iodophenol (10.0 g, 0.045 mol), tert-butyldimethylsilyl chloride (9.6 g, 0.064 mol) and imidiazole (9.3 g, 0.204 mol) were placed in a 250 mL two-necked flask, and 60 mL of THF after dewatering was poured and stirred. Six hours. After suction filtration, most of the solvent was removed by a rotary concentrator, and extracted with ethyl acetate and saturated brine. The filtrate was evaporated over anhydrous magnesium sulfate and concentrated under reduced pressure to give a pale orange. The liquid was finally purified by ruthenium column chromatography using n-hexane as an extract to obtain an orange liquid (30a).

Yield: 87%.

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 0.20 (s, 6H, (CH ₃ ) ₃ CSiO(C H ₃ ) ₂ -), 0.99 (s, 9H, (C H ₃ ) ₃ CSiO (CH _{3 2} -), 6.61-6.64 (d, 2H, aromatic protons), 7.50-7.53 (d, 2H, aromatic protons); IR (film) v _max / cm ^-1 662, 1220, 1225, 1256, 2928, 2934

1-2. Synthesis of (4-tert-butyl-dimethyloxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolan (4-tert- Butyl-dimethlsilyloxyphenyl)-4,4,5,5-tetrametyl-1,3,2-dioxaborolane(31a)

After heating and drying in a vacuum of 250 mL, the vacuum-dried starting material (30a) (10 g, 29.92 mmol) was injected into the reaction flask with a syringe and dried at -78 °C. After stirring for 5 minutes in the environment, 1.6 M n-butyllithium (30 mL, 44.87 mmol) was slowly dropped into the reaction flask at -78 ° C, and stirred for 2 hours, at which time the clear solution would appear white turbid, after which Then 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (15 mL, 59.83 mmol) was slowly dropped into the reaction flask at -78 °C, then slowly returned to room temperature. After the reaction was completed overnight, the reaction was completed, and the white solid was filtered off with suction. The filtrate was concentrated under reduced pressure and then extracted with water and ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and dried and concentrated to give a pale yellow liquid. Purification was carried out by ruthenium column chromatography (eluent: ethyl acetate / n-hexane = 1: 20) to give a pale yellow liquid (31a).

Yield: 77%, mp: 46 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 0.18 (s, 6H, (CH ₃ ) ₃ CSiO(C H ₃ ) ₂ -), 0.97 (s, 9H, (C H ₃ ) ₃ CSiO (CH _{3 ) 2} -), 1.30 (s, 12H, -BOC(C H ₃ ) ₂ -), 6.81-6.84 (d, 2H, -aromatic protons), 7.68-7.71 (d, 2H, -aromatic protons); IR ( Film)v _max /cm ^-1 1014,1090,1214,1262,1262,1264,1360,2930,2957,2978

1-3. Synthesis of Compounds (33a) and (33b)

Taking the compound 2-fluoro-1,1'-diphenyl-4-ol (3-afluoro-1,1'-biphenyl-4-ol) (33a) as an example, the synthesis steps are as follows: Take a 50 mL Compound (31a) (5 g, 15 mmol), 4-bromo-3-fluorophenol (2.674 g, 14 mmol) and K ₂ CO ₃ (15.48 g, 112 mmol) were placed in a double neck bottle, and Pd was taken in a glove box. (PPh ₃ ) ₄ (0.81 g, 0.7 mmol) was placed in a reaction flask, and wrapped with aluminum foil paper, and the mixed solvent of 1,2-dimethoxyethane/EtOH=3:1 which had been vacuum dried was taken out into a bottle, at 90 The mixture was heated under reflux at a temperature of ° C for 1 day. After completion of the reaction, the mixture was extracted with EtOAc EtOAc EtOAc (EtOAc) Purification by :6) gave a white solid (33a).

(33a) Yield: 65%, mp: 236 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 6.63 - 7.62 (m, 7H, aromatic protons), 8.66 (br, 2H, Ar-OH); IR (film) v _max / cm ^-1 1231, 1626, 2983, 3305

(33b) Yield: 65%, mp: 158 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 2.851 (s, 3H, -Ph-C H ₃ ), 6.67-7.12 (m, 7H, aromatic protons), 8.215 (d, 1H, -Ph (CH _{3 )} ) O H ), 8.348 (d, 1H, -PhO H ); IR(film)v _max /cm ^-1 1231,1607,2926,3305

1-4. Synthesis of compound 2-fluoro-1,1'-biphenyl-4,4'-dimethacrylate (M1) And 2-methyl-1,1'-biphenyl-4,4'-dimethacrylate (M2)

Taking the compound 2-fluoro-1,1'-diphenyl-4,4'-dimethacrylate (M1) as an example, the synthesis steps are as follows: The compound (33a) (1.78 g, 8.72 mmol) was placed in a 250 mL double-necked flask. After evacuating with a vacuum deaerator and three times of nitrogen gas, nitrogen was added to the addition funnel to make the reaction system anaerobic. Anhydrous state. Add triethylamine (6.3 mL, 48.6 mmol) and 50 mL of THF after removing water to dissolve at room temperature. Finally, methacryloyl chloride (3.4 mL, 34.88 mmol) was poured into the ice bath and reacted at room temperature. The next day. The mixture was filtered with suction and washed with EtOAc. EtOAc was evaporated, evaporated, evaporated, evaporated, evaporated, evaporated, evaporated, evaporated. Recrystallization gave a white solid.

(M1) Yield: 50%, mp: 118 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 2.08 (s, 6H, -C H ₃ C=CH ₂ ), 2.27 (s, 3H, -Ph(C H ₃ )-), 5.77-5.78 (t , 2H, trans-Me-C=C H ), 6.36-6.38 (t, 2H, cis-Me-C=C H ), 6.39-7.35 (m, 7H, aromatic protons); IR (film) v _max / Cm ^-1 874,944,1318,1633,2922

(M2) Yield: 51%, mp: 52 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 2.08 (s, 6H, -C H ₃ C=CH ₂ ), 2.27 (s, 3H, -Ph(C H ₃ )-), 5.77-5.78 (t , 2H, trans-Me-C=C H ), 6.36-6.38 (t, 2H, cis-Me-C=C H ), 6.39-7.35 (m, 7H, aromatic protons); IR (film) v _max / Cm ^-1 874,944,1318,1633,2922

¹³ C NMR (75 M Hz, CDCl ₃ , δ ppm): δ = 18.3, 18.4, 110.1, 110.8, 117.7, 117.8, 127.4, 127.8, 130.0, 130.9, 135.6, 135.8, 150.6, 165.8; IR (film) v _max /cm ^-1 882,944,1317,1636,2926; MS (EI-MS) m/z: 336; Calc. For C ₂₁ H ₂₀ O ₄ : C, 74.98; H, 5.99. Found: C, 75.18; H, 6.07

[Flowchart II]

Example 3 - Preparation of a photosensitive monomer of the formula (IV) (i.e., M3 in Scheme II)

3-1. Synthesis of (4-bromo-3-methyl-phenoxy)-tert-butyl-dimethyl silane (34a)

This synthetic step is similar to the synthetic step of the aforementioned compound (30a). After identification, the compound data is as follows: Yield: 92%

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 0.21 (s, 6H, (CH ₃ ) ₃ CSi(CH ₃ ) ₂ O-), 1.01 (s, 9H, (CH ₃ ) ₃ CSi(CH ₃ ) ₂ O-), 2.35 (s, 3H, PHC H ₃ ), 6.55-7.38 (m, 3H, aromatic protons); IR (film) v _max /cm ^-1 579, 1030, 1244, 1292, 1594, 2930, 2956

3-2. Synthesis of 2-[4-(tert-butyl-dimethyloxy)-2-methyl-phenyl]-4,4,5,5-tetramethyl-1,3,2- 2-[4-(tert-butyl-dimethyl-silanyloxy)-2-methyl-phenyl]-4,4,5,5-tetrametyl-1,3,2-dioxaborolane (35a)

This synthetic step is similar to the synthesis step of the aforementioned compound (31a). After identification, the compound data are as follows: yield: 75%, mp: 62 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 0.16 (s, 6H, (CH ₃ ) ₃ CSi(CH ₃ ) ₂ O-), 0.97 (s, 9H, (C H ₃ ) ₃ CSi (CH _{3 2} O-), 1.26 (s, 12H, -BOC(CH ₃ ) ₂ -), 2.48 (s, 3H, PHC H ₃ ), 6.62-7.66 (m, 3H, aromatic protons); IR (film) v _Max /cm ^-1 1013,1068,1215,1237,1598,2930,2957,2977

3-3. Synthesis of 2,2'-dimethyl-1,1'-diphenyl-4-ol (2,2'-dimethyl-1,1'-biphenyl-4-ol) (36a)

This synthetic step is similar to the synthesis step of the aforementioned compound (33a). After identification, the compound data are as follows: yield: 59%, mp: 130 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 1.95 (s, 6H, PHCH ₃ ), 6.66-6.87 (m, 6H, aromatic protons), 8.20 (s, 2H, -O H ), IR (film) v _max /cm ^-1 1234,1605,2965,3264

3-4. Synthesis of compound 2,2'-dimethyl-1,1'-diphenyl-4,4'-dimethacrylate (2,2'-Dimethyl-1,1'-biphenyl-4 ,4'-dimethacrylate)(M3)

This synthetic step is similar to the synthetic step of the aforementioned compound (M1). After identification, the compound data are as follows: yield: 50%, mp: 70 ° C

¹ H NMR (300 M Hz, CDCl ₃ , δ ppm): 2.06 (s, 6H, PHC H ₃ ), 2.08 (s, 6H, C H ₂ = C(CH ₃ ) C-), 5.77 (t, 2H, trans -Me-C=C H ), 6.36 (t, 2H, cis-Me-C=C H ), 6.97-7.26 (m, 6H, aromatic protons); ¹³ C NMR (75 M Hz, CDCl ₃ , δ ppm) :18.40,19.94,118.68,122.71,127.20,130.40,135.94,137.64,138.24,149.99,166.01;IR(film)v _max /cm ^-1 892,944,1318,1636,2924,3080;MS(EI-MS)m /z:350

Example 4 - Production of Liquid Crystal Display Panel Using Photosensitive Monomer of Formula (II)

1A to 1D are schematic cross-sectional views showing a manufacturing process of a liquid crystal display panel of the present embodiment.

As shown in FIG. 1A, a first substrate 111 and a second substrate 121 are provided. The first substrate 111 and the second substrate 121 are respectively provided with a first electrode 112 and a second electrode 122, and the first electrode 112 is disposed opposite to the second electrode 122. The first substrate 111 and the second substrate 121 may be substrates commonly used in the art, such as a plastic substrate or a glass substrate. In addition, the first electrode 112 and the second electrode 122 may also be transparent electrodes commonly used in the art, such as metal thin film electrodes, transparent conductive electrodes (ITO, IZO, ZnO, etc.). In the present embodiment, the first substrate 111 and the second substrate 121 are made of a glass substrate; and the first electrode 112 and the second electrode 122 are both ITO electrodes.

Next, as shown in FIG. 1B, a liquid crystal material is injected between the first substrate 111 and the second substrate 121, and the liquid crystal material comprises: a liquid crystal molecule and the photosensitive monomer provided in Embodiment 1. Here, the liquid crystal material may be injected between the first substrate 111 and the second substrate 121 by a method known in the art, including a dropping type liquid crystal injection process or a liquid crystal drawing process. Further, the liquid crystal material further includes a photoinitiator such as IRG907 (available from Ciba Corp.), but the present invention is not limited to such a photoinitiator. In the present embodiment, the liquid crystal material includes 99.6 wt% of liquid crystal molecules, 0.1 wt% of photoinitiator, and 0.3 wt% of the photosensitive monomer provided in Example 1.

Then, an energy is applied to polymerize the photosensitive monomers to form a polymer film on the first substrate 111 and the second substrate 121, respectively, as an alignment film 131, 132, as shown in FIG. 1C. Here, a voltage and an illumination process are used to carry out the polymerization reaction, and the illumination time may be from 20 seconds to 180 seconds. In the present embodiment, ultraviolet light is used as the illumination source, and the illumination time (exposure time) is 40 seconds, 80 seconds or 160 seconds, and three different samples can be obtained for subsequent testing.

In addition, in order to enhance the alignment effect, as shown in FIG. 1A, the first substrate 111 and the second substrate 121 of the present embodiment are further laminated with a first alignment layer 113 and a second layer made of polyacetamide. Alignment layer 123.

As shown in FIG. 1C, the liquid crystal display panel of the present embodiment is obtained by the above process, comprising: a first substrate 111 having a first electrode 112 disposed thereon; a second substrate 121 having a top portion thereon One by one a second electrode 122, and the first electrode 112 is disposed opposite to the second electrode 122; an alignment film 131, 132 is formed on the first electrode 112 and the second electrode 122: and a liquid crystal layer 13 is disposed on the first substrate 111 is between the second substrate 121. The liquid crystal layer 13 includes a liquid crystal molecule, and the alignment films 131 and 132 are polymer films obtained by polymerizing the photosensitive monomer provided in Example 1. In addition, the liquid crystal display panel of the present embodiment further includes a first alignment layer 113 and a second alignment layer 123 respectively disposed on the first electrode 112 and the second electrode 122, and the first alignment layer 113 and the second layer The alignment layer 123 is a polyethyleneamine layer.

Furthermore, as shown in FIG. 1D, since the alignment films 131 and 132 of the present embodiment have protrusions of a nano structure, the liquid crystal molecules can have a pretilt angle, so that when a voltage is applied, the liquid crystal molecules can be poured. The dark state shown in FIG. 1C is converted into a bright state as shown in FIG. 1D.

Example 5 - Production of Liquid Crystal Display Panel Using Photosensitive Monomer of Formula (III)

The manufacturing method and structure of the liquid crystal display panel of the present embodiment are the same as those of the fourth embodiment except that the photosensitive monomer provided in the second embodiment is used in the liquid crystal material to form the alignment films 131 and 132. Here, the illumination time (exposure time) of 40 seconds, 80 seconds or 160 seconds was also performed to obtain three different samples for subsequent testing.

Example 6 - Production of Liquid Crystal Display Panel Using Photosensitive Monomer of Formula (IV)

The manufacturing method and structure of the liquid crystal display panel of the present embodiment are the same as those of the fourth embodiment except that the photosensitive monomer provided in the third embodiment is used in the liquid crystal material to form the alignment films 131 and 132. Here, 40 seconds, 80 are also performed. Second or 160 seconds of illumination time (exposure time) to obtain three different samples for subsequent testing.

In the foregoing Examples 4 to 6, the alignment film was produced using only a single photosensitive monomer, but the present invention can also use a plurality of photosensitive monomers in combination to form an alignment film synthesized by copolymerization of different monomers.

Comparative example

The liquid crystal display panel of this comparative example was produced in the same manner as in Example 1 except that no photosensitive monomer was added to the liquid crystal material. Therefore, the liquid crystal display panel produced in this comparative example does not include the alignment film of Example 1.

Test Results

The alignment films obtained in the irradiation of 160 seconds of Examples 4 to 6 were subjected to surface analysis. After observation by SEM and AFM, it was found that the alignment films of Examples 4 to 6 did have a projection of a nanostructure, and their length, width and height were all in the range of 1-200 nm.

Here, the optical measurements of the nine different samples obtained in Examples 4 to 6 were carried out, and the results are shown in Figs. 2 to 4 .

As shown in FIG. 2, the horizontal axis represents the exposure time, and the vertical axis represents the rise time (Tr). When the driving voltage is changed from 0 V to 8 V, the liquid crystal panel rise time (Tr) of Examples 4 to 6 decreases as the exposure time increases; and at the same exposure time, Tr of Example 6 is maximum, and Example 4 is Tr is the smallest.

Further, the contrast (CR) and the operation threshold voltage (Vth) of the liquid crystal display panels obtained in Examples 4 to 6 were compared when the exposure time was 80 seconds. As shown in FIG. 3, wherein the horizontal axis represents Examples 4 to 6, the left vertical axis shows contrast. Degree (CR), while the right vertical axis shows the operating threshold voltage (Vth). The experimental results show that CR and Vth of Example 6 are the largest, while CR and Vth of Example 4 are the smallest.

If the light transmission characteristics of the liquid crystal panels of Examples 4 to 6 at different voltages are observed by the VT curve, as shown in FIG. 4, the horizontal axis is the voltage value, and the vertical axis is the light transmittance percentage, and the embedded chart is 1.4. Partial magnification of the percentage of light transmission at -3.4V. The experimental results show that when the exposure time of the liquid crystal display panel obtained in Examples 4 to 6 is 80 seconds, the liquid crystal panel of Example 4 has the highest transmittance at the same voltage, and the worst is the liquid crystal panel of Example 6. However, the liquid crystal panels obtained in Examples 4 to 6 had higher transmittance than the liquid crystal panels of Comparative Examples.

Example 7 - Preparation of an alignment layer by using a photosensitive monomer together with an acetamide monomer

The manufacturing method and structure of the liquid crystal display panel of this embodiment are the same as those of the embodiment 4 except that the photosensitive monomers provided in the embodiments 1 to 3 are not added to the liquid crystal material, but are added to the material forming the alignment layer. Therefore, the alignment layer of this example is an alignment layer obtained by copolymerizing the photosensitive monomer provided in Examples 1 to 3 with an acetamide imide.

According to this, as shown in FIG. 5, the structure of the liquid crystal display panel of the present embodiment includes: a first substrate 511, a first electrode 512 is disposed on the upper side thereof; and a second substrate 521 is disposed on the upper side thereof. a first electrode 522 is disposed opposite to the second electrode 522; a first alignment layer 513 and a second alignment layer 523 are formed on the first electrode 512 and the second electrode 522, respectively; A liquid crystal layer 53 is disposed between the first substrate 511 and the second substrate 521. Wherein, the material layers of the first alignment layer 513 and the second alignment layer 523 An alignment layer obtained by copolymerizing the photosensitive monomer provided in Examples 1 to 3 with an acetamide imide.

Example 8

The manufacturing method and structure of the liquid crystal display panel of this embodiment are the same as those of the embodiment 4 except that the photosensitive layer and the acetamide monomer provided by the embodiments 1 to 3 are used in the first alignment layer and the second alignment layer. (imide) an alignment layer that is copolymerized.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

111,511‧‧‧First substrate

112,512‧‧‧first electrode

113,513‧‧‧First alignment layer

121,521‧‧‧second substrate

122,522‧‧‧second electrode

123,523‧‧‧Second alignment layer

13,53‧‧‧Liquid layer

131,132‧‧‧Alignment film

1A to 1D are schematic cross-sectional views showing a manufacturing process of a liquid crystal display panel according to Embodiment 4 of the present invention.

Fig. 2 is a graph showing the relationship between the exposure time of the photosensitive monomer and the rise time of the liquid crystal panel.

Figure 3 is a graph showing the contrast and operating threshold voltage test results of different photosensitive monomers.

Figure 4 is a voltage-transmission curve of different photosensitive monomers.

Figure 5 is a schematic view of a liquid crystal display panel according to Embodiment 7 of the present invention.

111‧‧‧First substrate

112‧‧‧First electrode

113‧‧‧First alignment layer

121‧‧‧second substrate

122‧‧‧second electrode

123‧‧‧Second alignment layer

13‧‧‧Liquid layer

131,132‧‧‧Alignment film

Claims (17)

A photosensitive monomer for a liquid crystal layer or an alignment layer, which is represented by the following formula (I): Wherein; when each of R ₁ and R ₂ is selected from at chloro, bromo, iodo, nitro, cyano, C _1-12 alkyl, or at least one hydrogen atom is substituted with a halogen atom of the C _1-12 alkyl a, a is 1-4, and b is 0-4; and when one of R ₁ or R ₂ is fluorine, the other is selected from fluorine, chlorine, bromine, iodine, nitro, cyano, C One of C _1-12 alkyl groups having _1-12 alkyl groups or at least one hydrogen atom substituted by a halogen atom, a is 1-4, and b is 1-4. The photosensitive monomer according to claim 1, wherein each of R ₁ and R ₂ is independently a fluorine, a chlorine, a nitro group, a cyano group, a C _1-6 alkyl group, or a trifluoromethyl group. The photosensitive monomer according to claim 2, wherein each of R ₁ and R ₂ is independently fluorine or C _1-3 alkyl, a is 1-2, and b is 0-2. The photosensitive monomer according to claim 1, wherein the formula (I) is a formula (III) or a formula (IV): A liquid crystal display panel includes: a first substrate having a first electrode disposed thereon; a second substrate having a second electrode disposed thereon, and the first electrode is disposed opposite to the second electrode; an alignment film Forming on at least one of the first electrode and the second electrode; and a liquid crystal layer disposed between the first substrate and the second substrate; wherein the alignment film is a formula (I) The polymer film obtained by polymerizing the photosensitive monomer shown: Wherein; when each of R ₁ and R ₂ is selected from at chloro, bromo, iodo, nitro, cyano, C _1-12 alkyl, or at least one hydrogen atom is substituted with a halogen atom of C _1-12 alkyl, a is 1-4, and b is 0-4; and when one of R ₁ and R ₂ is fluorine, the other is selected from fluorine, chlorine, bromine, iodine, nitro, cyano, C _1- One of C _1-12 alkyl groups in which ₁₂ alkyl groups or at least one hydrogen atom is replaced by a halogen atom, a is 1-4, and b is 1-4. The liquid crystal display panel of claim 5, further comprising a first alignment layer disposed on the first electrode, and the first alignment layer It is a polyamidamine layer or a polymer layer synthesized by copolymerization of a hydrazine amine and a photosensitive monomer represented by the formula (I). The liquid crystal display panel of claim 5, further comprising a second alignment layer disposed on the second electrode, and the second alignment layer is a polyimide layer or a sub-layer A polymer layer synthesized by copolymerization of guanamine and a photosensitive monomer represented by the formula (I). The liquid crystal display panel of claim 5, wherein each of R ₁ and R ₂ is independently fluorine, chlorine, nitro, cyano, C _1-6 alkyl or trifluoromethyl. The liquid crystal display panel of claim 8, wherein each of R ₁ and R ₂ is independently a fluorine, a methyl group, or an ethyl group, a is 1-2, and b is 0-2. The liquid crystal display panel according to claim 5, wherein the formula (I) is the formula (III) or the formula (IV): A method for fabricating a liquid crystal display panel includes: providing a first substrate and a second substrate, wherein the first substrate and the second substrate are respectively provided with a first electrode and a second electrode, and the first electrode Opposite the second electrode system; implanting a liquid crystal material between the first substrate and the second substrate, and the liquid crystal material comprises: a liquid crystal molecule, and a photosensitive monomer represented by the following formula (I) : Wherein; when each of R ₁ and R ₂ is selected from at chloro, bromo, iodo, nitro, cyano, C _1-12 alkyl, or at least one hydrogen atom is substituted with a halogen atom of C _1-12 alkyl; a is 1-4, and b is 0-4; and when one of R ₁ and R ₂ is fluorine, the other is selected from fluorine, chlorine, bromine, iodine, nitro, cyano, C _1- One of C _1-12 alkyl groups in which ₁₂ alkyl groups or at least one hydrogen atom is replaced by a halogen atom, a is 1-4, and b is 1-4; and an energy is applied to polymerize the photosensitive monomer to form And a polymer film on at least one of the first substrate and the second substrate as an alignment film. The manufacturing method of claim 11, wherein the energy is a light source and a voltage. The method of claim 11, wherein before the injecting the liquid crystal material, the method further comprises: forming a first alignment layer on the first electrode, and the first alignment layer is a polyimide layer Or a polymer layer synthesized by copolymerization of a polyimide and a photosensitive monomer represented by the formula (I). The manufacturing method of claim 11, wherein before injecting the liquid crystal material, further comprising: forming a second alignment layer on the second electrode And the second alignment layer is a polyammonium layer or a polymer layer synthesized by copolymerization of a sulfonamide and a photosensitive monomer represented by the formula (I). The production method according to claim 11, wherein each of R ₁ and R ₂ is independently a fluorine, chlorine, nitro group, a cyano group, a C _1-6 alkyl group, or a trifluoromethyl group. The method of claim 15, wherein each of R ₁ and R ₂ is independently a fluorine, a methyl group, or an ethyl group, a is 1-2, and b is 0-2. The production method according to claim 11, wherein the formula (I) is the following formula (III) or formula (IV):