JP3382475B2 - Manufacturing method of color filter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter, and more particularly to a method for manufacturing a color filter using a printing method such as ink jet. The color filter manufactured by the present invention is used in the field of color liquid crystal display devices and the like.

[0002]

2. Description of the Related Art In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal displays, especially color liquid crystal displays, has increased. However, for further widespread use, it is necessary to drastically reduce the cost, and in particular, it is required to reduce the cost of the color filter, which is heavy in terms of cost.

In order to satisfy such requirements, a method of manufacturing a color filter using an ink jet is as follows:
JP-A-4-121702, JP-A-6-34763
No. 7, etc., describes a method of providing a partition on a transparent substrate with a material having a different critical surface tension from the substrate and applying ink between the partitions.

However, in these methods, since the partition also serves as the black matrix, it is necessary to have a sufficient thickness for ensuring the light-shielding property. As shown in FIG. 2, even if the ink 3 is applied to the openings (portions that become pixels) surrounded by the partition 5 after such a thick partition 5 is formed, the ink does not reach the corner 6 below the opening. There is a possibility that voids may be generated without being filled, and as a result, there is a problem in that the corners of pixels are not sufficiently colored and defects such as white spots occur.

[0005]

DISCLOSURE OF THE INVENTION According to the present invention, when partitions are formed on a transparent substrate and then colored ink is applied between the partitions to manufacture a color filter, the partitions are sufficiently filled with ink. And a method for producing a color filter having no white spots, no color mixture with adjacent pixels, and exhibiting high contrast when used in a liquid crystal display device and the like, and excellent performances produced by this method. The purpose is to provide a color filter.

[0006]

The present invention provides a method for producing a color filter, which comprises a step of forming a partition portion on a transparent substrate and a step of applying a colored ink to a gap between the partition portions. Is a resin component and a black pigment
Or multiple layers with different critical surface tensions containing dye components
Formed by stacking, the transparent substrate side of the partition (lower layer
Side) bottom layer and surface side (upper layer side) top layer, and
As the material of the colored ink, the critical surface tension of each is
It is characterized in that the one satisfying the relation of the following Expression 1 is used.
The present invention relates to a method for manufacturing a color filter. (Formula 1) [Bottom layer of partition]>[Ink]> [Top layer of partition] (however, [Bottom layer of partition], [Ink] and [Partition]
The uppermost layer of the cut portion] represents each critical surface tension. ) In the present invention, the material of the partition and the colored ink is
Then, the respective critical surface tensions are expressed by the following equations 2-4.
It is preferable to use the ones that simultaneously fill. (Formula 2) [Bottom layer of partition part] ≧ 35 dyne / cm (Formula 3) [Top layer of partition part] <35 dyne / cm (Formula 4) [Bottom layer of partition part] -5 dyne / cm> [ Ink >> [ top layer of partition ] +5 dynes / cm (however, [bottom layer of partition], [ink] and
The uppermost layer of the cut portion] represents each critical surface tension. )

In the present invention, the partition portion is laminated from the transparent substrate side (lower layer side) to the surface side (upper layer side), and a plurality of layers having different critical surface tensions are laminated in order from a layer having a large critical surface tension to a layer having a small critical surface tension. It is preferable to form it.

The partition may be a multi-layer having three layers or more, but if it has two layers, the manufacturing process can be simplified. At this time, a layer having a high critical surface tension is a lower layer, and a layer having a low critical surface tension is an upper layer.

The present invention further includes a partition portion on the transparent substrate.
And by applying colored ink to the gap between the partition parts.
A color filter having a pixel portion formed by
The partition part is made of a resin component and a black pigment or dye.
Consisting of multiple layers with different critical surface tensions containing the ingredients,
The lowermost layer and the front surface of the partition section on the transparent substrate side (lower layer side)
Surface side (upper layer side), and the critical surface of the colored ink
Color that is characterized in that the tension satisfies the relationship of the following expression 1.
-Regarding filters. (Formula 1) [Bottom layer of partition]>[Ink]> [Top layer of partition] (however, [Bottom layer of partition], [Ink] and [Partition]
The uppermost layer of the cut portion] represents each critical surface tension. )

[0010]

In the present invention, as described above, the lowermost layer of the partition portion is made of a material which easily wets the ink. Therefore, since the ink penetrates to the corners of the partition part, the blank defect does not occur. In addition, since the uppermost layer of the partition portion easily repels ink, the ink does not flow over the partition portion to the adjacent pixel and cause color mixing.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The material forming the partition used in the present invention contains a resin component and a black pigment or dye component, and may be photosensitive or non-photosensitive.

When a non-photosensitive material is used, the partition portion is formed on the transparent substrate by etching or lift-off method using photoresist, printing method such as screen printing, offset printing, gravure printing, or dry film. It can be formed into a pattern using a known method such as a sheet transfer method. Usually, in these forming methods, a composition containing a suitable solvent in addition to the above resin component and black pigment component is used.

Examples of the resin component having a critical surface tension of 35 dyne / cm or more include polyethylene terephthalate (43 dyne / cm) and 6-6 nylon (42 dyne / cm).
cm), methyl polyacrylate (39 dyne / cm),
Examples of the resin component having a critical surface tension of less than 35 dyne / cm include polyvinyl hexafluoride (16 dyne / cm) and polytrifluoride. Ethylene (22 dynes / c
m), polydimethylsiloxane (24 dyne / cm),
Examples thereof include polyethylene (31 dynes / cm).

In addition, in order to form the partition portion using a photosensitive material, it is possible to form the thin film on the entire surface by, for example, spin coating, followed by exposure and development. In this case, a photoresist having a required critical surface tension can be appropriately selected from known photoresists and used. For example, as the photoresist having a critical surface tension of 35 dyne / cm or more, a photoresist material made of a mixture of a naphthoquinonediazide compound such as naphthoquinonediazide sulfonate and a phenol novolac resin can be used.

As the black pigment component, carbon black, organic pigment, etc. can be used.

Further, in order to obtain the required critical surface tension, for example, a water repellent such as amorphous fluoropolymer,
The surface tension may be adjusted by adding a hydrophilic agent such as a silane coupling material.

First, preferably, a lower layer of the partition portion is formed into a pattern using a material having a large critical surface tension first, and then a material having a critical surface tension smaller than this layer is used so as to overlap the pattern of the lower layer. Another layer is formed in a pattern. In this case, the method of forming each layer may be different depending on the material used.

The critical surface tension required for the partition is
At least the surface that comes into contact with the ink is sufficient, and the inside is not limited to such a material.

The ink used in the present invention is an aqueous solution containing a pigment, a water-soluble dye and the like, an appropriate resin, and optionally an organic solvent which can be mixed with water and other additives.

By adjusting the material of the partition portion and the material of the ink so as to simultaneously satisfy the relation of the above-mentioned formula 1, preferably the relation of the formulas 2 to 4, the ink is applied on the partition portion. It can be easily repelled, and the pixel portion in the gap between the partition portions can be easily wet.

As the ink application method, a general printing method such as offset printing, gravure printing, screen printing or the like can be used. In particular, according to the inkjet printing method using an inkjet printing machine, a plate is not used during printing. Therefore, if the diameter of the ink droplet is manipulated, high-precision patterning is possible, which is preferable.

As the transparent substrate used in the present invention, for example, glass is often used, but a plastic film or a plastic sheet may be used. Further, if necessary, in order to improve the adhesion between the transparent substrate and the partition and the colored ink, a thin film for improving the adhesion can be formed in advance on the transparent substrate.

[0024]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 On the glass substrate 4 of FIG. 1, polyethylene terephthalate (critical surface tension 43 dyne /
cm) and carbon black as a black material are mixed in toluene, a predetermined pattern is printed by a screen printing machine, and then left in an oven at 200 ° C. for 1 hour to form a lower layer of a partition part having a line width of 20 μm and a height of 1 μm. 1 was formed in a pattern.

Next, a silicone resin (critical surface tension 24
(Dyne / cm) and a black dye as a black material are mixed in ethanol, and the mixture is drawn by an inkjet printing machine so as to overlap the lower layer pattern and dried at 150 ° C. for 30 minutes.
The partition upper layer 2 was formed in a pattern having a height of 1 μm.

A critical surface tension of 35 is obtained by using an ink jet device in the portion surrounded by the partition portion formed by the two layers.
When the red, green, and blue inks 3 of dyne / cm were ejected, the ink penetrated to the corners of the pixels, while the ink did not mix into the adjacent pixels.

As a result, it was possible to manufacture a color filter in which the corners of the pixel were sufficiently colored and had no white spots.

[Comparative Example 1] Polyethylene terephthalate (critical surface tension: 43 dynes / cm) was formed on a glass substrate by the same forming method as that for forming the lower layer of the partition portion in Example 1.
The partition part including the was formed with a line width of 20 μm and a height of 2 μm.

Next, in the same manner as in Example 1, ink having a critical surface tension of 35 dynes / cm was ejected to a portion surrounded by the partition by using an ink jet device. A color mixture with

[Comparative Example 2] A partition portion containing a silicone resin (critical surface tension of 24 dynes / cm) was formed on a glass substrate by the same forming method as that for forming the upper layer of the partition portion of Example 1, and the line width was 20 μm. It was formed with a height of 1 μm.

Next, as in Example 1, ink having a critical surface tension of 35 dynes / cm was ejected to a portion surrounded by the partition by using an ink jet device. The part that did not penetrate remained.

[0033]

According to the present invention, when a partition is formed on a transparent substrate and then colored ink is applied between the partitions to produce a color filter, the space between the partitions is sufficiently filled with the ink. Method for producing a color filter having no omission, no color mixture with adjacent pixels, and exhibiting high contrast when used in a liquid crystal display device, etc., and a color filter produced by this method and exhibiting excellent performance Can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a color filter formed by a manufacturing method of the present invention.

FIG. 2 is a cross-sectional view of a color filter formed by a conventional manufacturing method.

[Explanation of symbols]

1 Partition lower layer 2 Upper part of partition 3 colored ink 4 glass substrates 5 dividers 6 White spots

─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Asako Takekoshi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Junichi Sakamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. Within the corporation (56) Reference JP-A-6-186416 (JP, A) JP-A-6-347637 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G02B 5/20 101

Claims (5)

(57) [Claims] 1. A method of manufacturing a color filter, comprising: a step of forming a partition part on a transparent substrate; and a step of applying a colored ink to a gap of the partition part, wherein the partition part comprises a resin component and a black pigment. Alternatively, it is formed by laminating a plurality of layers containing dye components and having different surface tensions, and the lowermost layer on the transparent substrate side (lower layer side) and the front surface of the partition part.
The uppermost layer on the surface side (upper layer side) and as the material for the colored ink
And each critical surface tension satisfies the relation of the following formula 1.
Of color filters characterized by using
Build method. (Formula 1) [Bottom layer of partition]>[Ink]> [Top layer of partition] (however, [Bottom layer of partition], [Ink] and [Partition]
The uppermost layer of the cut portion] represents each critical surface tension. ) As wherein the material of the partition portion and the color ink, each of the critical surface tension, claim 1, wherein the use of which satisfies the following relationship of equation 2-4 simultaneously
A method for producing the described color filter. (Formula 2) [Bottom layer of partition part] ≧ 35 dyne / cm (Formula 3) [Top layer of partition part] <35 dyne / cm (Formula 4) [Bottom layer of partition part] -5 dyne / cm> [ Ink >> [top layer of partition] +5 dynes / cm (however, [bottom layer of partition], [ink] and
The uppermost layer of the cut portion] represents each critical surface tension. ) 3. The transparent substrate side (lower layer side) of the partition section
3. The color filter according to claim 1, wherein a plurality of layers having different critical surface tensions are laminated in this order from a layer having a large critical surface tension to a layer having a small critical surface tension. Production method. The method according to claim 4, wherein said partitioning portion, collar according to any one of claims 1 to 3 in which the layer with the greater critical surface tension and a lower layer, and forming by laminating two layers of small layer as the upper layer Filter manufacturing method. 5. A partition part on a transparent substrate, and the partition part
An image formed by applying colored ink to the gap
In a color filter having a base portion, the partition
The critical part contains a resin component and a black pigment or dye component.
It is composed of a plurality of layers having different surface tensions, and is the lowermost layer on the transparent substrate side (lower layer side) of the partition and the front surface.
Surface side (upper layer side), and the critical surface of the colored ink
Color that is characterized in that the tension satisfies the relationship of the following expression 1.
ー Filter. (Formula 1) [Bottom layer of partition]>[Ink]> [Top layer of partition] (however, [Bottom layer of partition], [Ink] and [Partition]
The uppermost layer of the cut portion] represents each critical surface tension. )