Patent Publication Number: US-2013250217-A1

Title: Liquid Crystal Display Panel and Manufacturing Method Thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of liquid crystal displaying techniques, and in particular to a liquid crystal display panel and manufacturing method thereof. 
     2. The Related Arts 
     As the technology develops, video products, in particular, digital video or audiovisual products have been a part of daily lives. Among these digital video or audiovisual products, the display device is an important element for displaying information. Viewers can read information from the display device as well as operate the device. 
     Liquid crystal display (LCD) panel is a major component of a liquid crystal display device, mainly comprising a color filter (CF) substrate and a thin film transistor (TFT) substrate. The two substrates are disposed with transparent electrodes on inner surfaces facing each other, and a layer of liquid crystal molecules is disposed between the two substrates. The liquid crystal display panel realizes the display capability through the electric field controlling the orientation of liquid crystal molecules to change the optical polarization and with the polarizer for optical passing or blockage. 
     CF substrate and TFT substrate usually use a radiation curing agent (seal) for assembly. The radiation curing agent usually comprises acrylic, epoxy, photoinitiator, and so on. The radiation curing agent is cured through heating or UV radiation, or both, so CF substrate and TFT substrate are glued together. The current mainstream curing technique is to use both heating and UV radiation. When UV radiation is used to cure the radiation curing agent, the UV light is radiated from one side of TFT substrate. During the curing process, a UV mask is placed between UV light and the TFT substrate to shield UV light from radiating upon the display area and to prevent the UV light from damaging the PI material and liquid crystal material in the display area. 
     The above method has the following shortcomings: when the panel size changes, a corresponding UV mask must be manufactured, which increases the manufacture cost. Also, because the peripheral of TFT substrate usually includes large-area opaque metal routes, which may shield the radiation curing agent under the metal routes from UV light curing and cause the radiation curing agent to suffer insufficient curing. 
     SUMMARY OF THE INVENTION 
     The technical issue to be addressed by the present invention is to provide a liquid crystal display panel and manufacturing method thereof to solve the problems of high manufacturing cost and insufficient curing of known techniques. 
     The present invention provides a manufacturing method of liquid crystal display panel, which comprises the steps of: preparing a first substrate and a second substrate, the first substrate and second substrate being disposed oppositely, the first substrate further comprising a color filter array area and a first non-display area disposed in peripheral of the color filter array area, the first substrate or the second substrate being coated with radiation curing agent corresponding to the first non-display area; using curing radiation to shine on the first substrate from a side of the first substrate away from the second substrate so that the incident curing radiation to the color filter array area being absorbed by the color filter array area, and the incident curing radiation to the first non-display area curing the radiation curing agent to adhere the first substrate and the second substrate. 
     According to a preferred embodiment of the present invention, the second substrate comprises a thin film transistor array area corresponding to the color filter array area, and a second non-display area disposed in peripheral of the thin film transistor array area, the second non-display area includes a first black matrix, and the radiation curing agent is coated on the first black matrix or the area on the first non-display area corresponding to the first black matrix. 
     According to a preferred embodiment of the present invention, the color filter array area comprises a plurality of color filter units arranged in an array format, and thin film transistor array area comprises a second black matrix corresponding to border area between color filter units. 
     According to a preferred embodiment of the present invention, the first black matrix and the second black matrix are formed at the same time. 
     According to a preferred embodiment of the present invention, the color filter array area comprises a plurality of color filter units arranged in an array format, and a second black matrix disposed between color filter units. 
     According to a preferred embodiment of the present invention, the radiation curing agent is an UV curing agent and the curing radiation is UV light. 
     The present invention provides a liquid crystal display panel, which comprises: a first substrate, further comprising color filter array area and a first non-display area disposed in peripheral of the color filter array area; a second substrate, disposed opposite to the first substrate, further comprising a thin film transistor array area corresponding to the color filter array area, and a second non-display area disposed in peripheral of the thin film transistor array area, the second non-display area including a first black matrix; radiation curing agent, coating on the first black matrix to adhere the first substrate and the second substrate. 
     According to a preferred embodiment of the present invention, the color filter array area comprises a plurality of color filter units arranged in an array format, and thin film transistor array area comprises a second black matrix corresponding to border area between color filter units. 
     According to a preferred embodiment of the present invention, the first black matrix and the second black matrix are formed at the same time. 
     According to a preferred embodiment of the present invention, the color filter array area comprises a plurality of color filter units arranged in an array format, and a second black matrix disposed between color filter units. 
     According to a preferred embodiment of the present invention, the radiation curing agent is an UV curing agent. 
     The present invention provides a manufacturing method of liquid crystal display panel, which comprises the steps of: preparing a first substrate and a second substrate, the first substrate and second substrate being disposed oppositely, the first substrate further comprising a color filter array area and a first non-display area disposed in peripheral of the color filter array area, the second substrate further comprising a thin film transistor array area corresponding to the color filter array area, and a second non-display area disposed in peripheral of the thin film transistor array area, the second non-display area including a first black matrix, the color filter array area comprising a plurality of color filter units arranged in an array format, the thin film transistor array area comprising second black matrix corresponding to border area between color filter units; the first back matrix or the area of the first non-display area corresponding to the first black matrix being coated with radiation curing agent; using curing radiation to shine on the first substrate from a side of the first substrate away from the second substrate so that the incident curing radiation to the color filter array area being absorbed by the color filter array area, and the incident curing radiation to the first non-display area curing the radiation curing agent to adhere the first substrate and the second substrate. 
     According to a preferred embodiment of the present invention, the first black matrix and the second black matrix are formed at the same time. 
     According to a preferred embodiment of the present invention, the radiation curing agent is an UV curing agent and the curing radiation is UV light. 
     The efficacy of the present invention is that to be distinguished from the state of the art. The manufacturing method of liquid crystal display device according to the present invention uses curing radiation to shine from one side of the substrate having the color filter array area. By using color filter array area to absorb the incident the curing radiation and using the non-display area in the peripheral area of the color filter array area to allow the curing radiation to pass through and cure the radiation curing agent, the method effectively solves the insufficient curing problem caused by the shielding of metal routes of the peripheral of thin film transistor array area and reduces the manufacture cost of the liquid crystal display panel without using UV mask. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To make the technical solution of the embodiments according to the present invention, a brief description of the drawings that are necessary for the illustration of the embodiments will be given as follows. Apparently, the drawings described below show only example embodiments of the present invention and for those having ordinary skills in the art, other drawings may be easily obtained from these drawings without paying any creative effort. In the drawings: 
         FIG. 1  is a schematic view showing the flowchart of manufacturing method of liquid crystal display panel according to the present invention; 
         FIG. 2  is a schematic view showing an embodiment of structure of the liquid crystal display panel manufactured according to the method in  FIG. 1 ; and 
         FIG. 3  is a schematic view showing another embodiment of structure of the liquid crystal display panel manufactured according to the method in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following detailed description refers to figures and embodiments of the present invention. 
       FIG. 1  is a schematic view showing the flowchart of manufacturing method of liquid crystal display device according to the present invention, and  FIG. 2  is a schematic view showing an embodiment of structure of the liquid crystal display panel manufactured according to the method in  FIG. 1 . The manufacturing method of liquid crystal display panel comprises the following steps: 
     Step S 100 : preparing a first substrate  21  and a second substrate  22 , the first substrate  21  and the second substrate  22  being disposed oppositely. 
     In the present embodiment, first substrate  21  further comprises a color filter array area  211  and a first non-display area  212  disposed in peripheral of color filter array area  211 . Second substrate  22  comprises a thin film transistor. array area  221  corresponding to color filter array area  211 , and a second non-display area  222  disposed in peripheral of thin film transistor array area  221 . Second non-display area  222  includes a first black matrix  2221 . Thin film transistor array area  221  comprises an array area having thin film transistor (TFT, not shown) and pixel electrodes (not shown). First black matrix  2221  surrounds thin film transistor array area  221 , for preventing the peripheral area from bad conduction caused by the curing radiation diffraction. 
     In the present embodiment, color filter array area  211  comprises a plurality of color filter units  2111  arranged in an array format, and second black matrix  2112  between color filter units  2111 ; wherein a plurality of color filter units  2111  is for allowing pre-defined wavelength light to pass, and reflecting or absorbing other wavelength light to achieve the color display of liquid crystal display panel. A plurality of color filter units  2111  usually is arranged in an interweaving manner according to different base color, for example, red, green, and blue. Second black matrix  2112  is mainly for preventing light leaking between color filter units  2111  to enhance the color contrast of liquid crystal display panel. 
     In the present embodiment, the area of first non-display area  212  corresponding to first black matrix  2221  is coated with radiation curing agent  23 . In another embodiment, radiation curing agent  23  can also be coated onto first black matrix  2221 , or any appropriate area on first substrate  21  or second substrate  22  corresponding to first non-display area  212 . 
     Step S 200 : using curing radiation to shine on first substrate  21  from a side of first substrate  21  away from second substrate  22  so that the incident curing radiation to color filter array area  211  being absorbed by color filter array area  211 , and the incident curing radiation to first non-display area  212  curing radiation curing agent  23  to adhere first substrate  21  and second substrate  22 . 
     In the present embodiment, radiation curing agent  23  is preferably an UV curing agent and the curing radiation is preferably UV light. When UV light shines from one side of first substrate  21 , color filter units  2111  and second black matrix  2112  of color filter array area  211  on first substrate  21  will absorb about 95% of the UV light, and first non-display area  212  in the peripheral of color filter array area  211  cannot absorb any UV light. After the incident UV light arriving at radiation curing agent  23  on first non-display area  212 , the photoinitiator in radiation curing agent  23  absorbs the photonic energy of UV light and is decomposed into free radical causing the monomers to polymerize to adhere first substrate  21  and second substrate  22 ; wherein during the curing, the preferred manner is to use both heating and curing radiation. 
       FIG. 3  is a schematic view showing another embodiment of structure of the liquid crystal display panel manufactured according to the method in  FIG. 1 . As shown in  FIG. 3 , the liquid crystal display panel of the present invention comprises a first substrate  31  and a second substrate  32 , disposed oppositely. 
     In the present embodiment, first substrate  31  further comprises a color filter array area  311  and a first non-display area  312  disposed in peripheral of color filter array area  311 . Second substrate  32  comprises a thin film transistor array area  321  corresponding to color filter array area  311 , and a second non-display area  322  disposed in peripheral of thin film transistor array area  321 . Second non-display area  322  includes a first black matrix  3221 . Thin film transistor array area  321  includes second black matrix  3211 . Color filter array area  311  comprises a plurality of color filter units  3111 , arranged in an array format. Second black matrix  3211  is located at an area corresponding to border area between color filter units  3111 . 
     In the present embodiment, the area of first non-display area  312  corresponding to first black matrix  3221  is coated with radiation curing agent  33 . In another embodiment, radiation curing agent  33  can also be coated onto first black matrix  3221 , or any appropriate area on first substrate  31  or second substrate  32  corresponding to first non-display area  312 . 
     The difference between the present embodiment and the embodiment in  FIG. 2  is that, first black matrix  3221  and second black matrix  3211  are both formed on second substrate  32 , and can be formed at the same time to eliminate the step of forming second black matrix  3211  on first substrate  31 , and simplifies the manufacture process. When curing radiation shines on first substrate  31  from one side of first substrate  31  away from second substrate  32 , color filter units  3111  of color filter array area  311  on first substrate  31  will absorb most of the curing radiation, and first non-display area  312  in the peripheral of color filter array area  311  cannot absorb any curing radiation, resulting in curing radiation curing agent  33 . At this point, even though a small amount of curing radiation will penetrate from between color filter units  3111 , the penetrating curing radiation will be shielded by second black matrix  3211  on second substrate  32 ; hence, having no impact on display effect. 
     The present invention further provides liquid crystal display panels manufactured according to the aforementioned manufacturing methods. The structures are described in details in the above description and are thus not repeated here. 
     With the above method, the present invention uses curing radiation to shine from one side of the substrate having the color filter array area. By using color filter array area to absorb the incident the curing radiation and using the non-display area in the peripheral area of the color filter array area to allow the curing radiation to pass through and cure the radiation curing agent, the method effectively solves the insufficient curing problem caused by the shielding of metal routes of the peripheral of thin film transistor array area and reduces the manufacture cost of the liquid crystal display panel without using UV mask. 
     Embodiments of the present invention have been described, but not intending to impose any unduly constraint to the appended claims. Any modification of equivalent structure or equivalent process made according to the disclosure and drawings of the present invention, or any application thereof, directly or indirectly, to other related fields of technique, is considered encompassed in the scope of protection defined by the clams of the present invention.