Coating processes – Optical element produced – Transparent base
Reexamination Certificate
1997-02-14
2001-07-10
Beck, Shrive (Department: 1762)
Coating processes
Optical element produced
Transparent base
C427S162000, C427S287000, C427S422000, C118S216000, C118S313000, C118S315000, C347S017000, C347S106000, C347S107000
Reexamination Certificate
active
06258405
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a color filter manufacturing method and apparatus for manufacturing a color filter by discharging inks onto a substrate using ink-jet heads and coloring each pixel of the color filter, a color filter, a display device, an apparatus having the display device, and a print method.
2. Description of the Related Art
With recent advances in personal computers, especially portable personal computers, the demand tends to arise for liquid crystal displays, especially color liquid crystal displays. However, in order to further popularize the use of liquid crystal displays, a reduction in cost must be achieved. Especially, it is required to reduce the cost of a color filter which occupies a large proportion of the total cost. Various methods have been tried to satisfy the required characteristics of color filters while meeting the above requirements. However, any method capable of satisfying all the requirements has not been established. The respective methods will be described below.
The first method is a pigment dispersion method, which is currently replacing a dyeing method. In this method, a pigment-dispersed photosensitive resin layer is formed on a substrate and patterned into a single-color pattern. This process is repeated three times to obtain R, G, and B color filter layers.
The second method is the dyeing method. In the dyeing method, a water-soluble polymer material as a dyeable material is coated on a glass substrate, and the coating is patterned into a desired shape by a photolithography process. The obtained pattern is dipped in a dye bath to obtain a colored pattern. This process is repeated three times to form R, G, and B color filter layers.
The third method is an electrodeposition method. In this method, a transparent electrode is patterned on a substrate, and the resultant structure is dipped in an electrodeposition coating fluid containing a pigment, a resin, an electrolyte, and the like to be colored in the first color by electrodeposition. This process is repeated three times to form R, G, and B color filter layers. Finally, these layers are calcined.
The fourth method is a print method. In this method, a pigment is dispersed in a thermosetting resin, a print operation is performed three times to form R, G, and B coatings separately, and the resins are thermoset, thereby forming colored layers. In either of the above methods, a protective layer is generally formed on the colored layers.
The point common to these methods is that the same process must be repeated three times to obtain layers colored in three colors, i.e., R, G, and B. This causes an increase in cost. In addition, as the number of processes increases, the yield decreases. In the electrodeposition method, limitations are imposed on pattern shapes which can be formed. For this reason, with the existing techniques, it is difficult to apply this method to TFTs. In the print method, a pattern with a fine pitch is difficult to form because of poor resolution and poor evenness.
In order to eliminate these drawbacks, methods of manufacturing color filters by an ink-jet system are disclosed in Japanese Patent Laid-Open Nos. 59-75205, 63-235901, and 1-217320. In these methods, coloring solutions containing coloring agents of three colors, i.e., R (red), G (green), and B (blue), are sprayed on a transparent substrate by an ink-jet system, and the respective coloring solutions are dried to form colored image portions. In such an ink-jet system, R, G, and B filter elements (pixels) can be formed at once, allowing great simplification of the manufacturing process and a great reduction in cost.
In a color filter used for a general liquid crystal display device or the like, the opening portions (i.e., pixels) of the black matrix which partition off the respective pixels are rectangular, whereas the shapes of inks discharged from ink-jet heads are almost spherical. It is therefore difficult to discharge a required amount of ink for one pixel at once and uniformly spread the ink over the entire opening portion of the black matrix. For this reason, a plurality of inks are discharged onto each pixel while the ink-jet head is scanned with respect to the substrate, thereby coloring each pixel. In this case, if a plurality of inks are simply discharged onto the respective pixels uniformly, density irregularity may occur between a plurality of pixels in the process of coloring the pixels in the scanning direction when, for example, the amounts of inks discharged vary as the state of the ink-jet head changes over time. That is, the coloring density of the pixels colored in the first period of the scanning operation may differ from that of the pixels colored in the second period of the scanning operation.
In addition, a color filter is to be colored by using a multi-head having a plurality of ink discharging nozzles in a direction substantially perpendicular to the scanning direction, the amounts of ink discharged from the respective nozzles vary, and hence density irregularity may occur between the pixels arrayed in the direction substantially perpendicular to the scanning direction.
Such a problem is posed not only in the manufacture of the above color filter but also in a general printing operation using an ink-jet head.
SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above problems, and has as its object to provide a color filter manufacturing method and apparatus which can manufacture a high-quality color filter with little density irregularity, a color filter manufactured by the method and apparatus, a display device having the color filter, an apparatus having the display device, and a print method of performing a print operation with little density irregularity.
In order to solve the above problems and achieve the above objects, according to the present invention, there is provided a method of manufacturing a color filter by coloring the respective pixels with a plurality of discharged inks arranged in a scanning direction while relatively scanning an ink-jet head over a substrate, the ink-jet head having a plurality of ink discharging nozzles in a direction substantially perpendicular to the scanning direction, comprising the step of performing a coloring operation while changing an ink discharging pattern for each of the arrayed pixels or each pixel group.
According to the present invention, there is provided an apparatus for manufacturing a color filter by coloring the respective pixels with a plurality of discharged inks arranged in a scanning direction while relatively scanning an ink-jet head over a substrate, the ink-jet head having a plurality of ink discharging nozzles in a direction substantially perpendicular to the scanning direction, comprising control means for controlling the ink-jet head to perform a coloring operation while changing an ink discharging pattern for each of the arrayed pixels or each pixel group.
According to the present invention, there is also provided a color filter manufactured by coloring the respective pixels with a plurality of discharged inks arranged in a scanning direction while relatively scanning an ink-jet head over a substrate, the ink-jet head having a plurality of ink discharging nozzles in a direction substantially perpendicular to the scanning direction, wherein a coloring operation is performed while an ink discharging pattern is changed for each of the arrayed pixels or each pixel group.
In addition, according to the present invention, there is provided a display device having a color filter manufactured by coloring the respective pixels with a plurality of discharged inks arranged in a scanning direction while relatively scanning an ink-jet head over a substrate, the ink-jet head having a plurality of ink discharging nozzles in a direction substantially perpendicular to the scanning direction, comprising a color filter colored by changing an ink discharging pattern for each of the arrayed pixels or each pixel group, and light amount changing mea
Fujiike Hiroshi
Wada Satoshi
Yamaguchi Nobuhito
Yokoi Hideto
Beck Shrive
Calcagni Jennifer
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
LandOfFree
Color filter manufacturing method and apparatus, color... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Color filter manufacturing method and apparatus, color..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color filter manufacturing method and apparatus, color... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2564088