WO2013162071A1

WO2013162071A1 - Method for forming cured layer or cured pattern, method for producing color filter, and color filter, solid-state imaging device and liquid crystal display device produced by using the methods

Info

Publication number: WO2013162071A1
Application number: PCT/JP2013/062870
Authority: WO
Inventors: Mitsuji Yoshibayashi
Original assignee: Fujifilm Corporation
Priority date: 2012-04-27
Filing date: 2013-04-26
Publication date: 2013-10-31
Also published as: TW201348866A; KR20140137015A; CN104246547A; JP2013231878A

Abstract

The invention is directed to a method for forming a cured layer or cured pattern, including: heating, in an environment where oxygen concentration is 100 ppm or less, a coating layer formed by applying a polymerizable composition containing a compound having a heat-polymerizable group onto a substrate or a pattern formed by the coating layer.

Description

DESCRIPTION

Title of Invention

METHOD FOR FORMING CURED LAYER OR CURED PATTERN, METHOD FOR PRODUCING COLOR FILTER, AND COLOR FILTER, SOLID-STATE IMAGING DEVICE AND LIQUID CRYSTAL DISPLAY DEVICE PRODUCED BY USING THE METHODS

Technical Field

The present invention relates to a method for forming a cured layer or cured pattern, a method for producing a color filter, and a color filter, solid-state imaging device and liquid crystal display device produced by using the methods.

Background Art

For instance, a transparent film for use in a solid-state imaging device is ordinarily obtained by coating a transparent polymerizable composition on a substrate and then subjecting the coating layer to a post-baking treatment.

Also, a color filter for use in a solid-state imaging device is ordinarily obtained by irradiating a colored layer formed from a colored radiation-sensitive composition with an ultraviolet ray through a prescribed mask pattern, subjecting the exposed colored layer to a development processing with an alkali solution to from a pattern image, and then subjecting the pattern image to a post-baking treatment. Thus, a color filter in which organic pixels of plural colors, for example, a red color pixel, a green color pixel or a blue color pixel, are two-dimensionally arrayed on a support, for example, a semiconductor substrate is provided.

Further, the transparent film is ordinarily formed on the color filter to form a microlens whereby the solid-state imaging device is constituted.

By the way, increase in the number of pixels in the solid-state imaging device is remarkable in recent years and when it is compared with a traditional solid-state imaging device having the same inch size, reduction of pixel size is noticeable. Further, along with the reduction of pixel size, performance demand on color separation becomes strict, and in order to maintain device characteristics, for example, color shading characteristics or color mixing prevention, performances, for example, reduction in thickness, rectangularization or elimination of overlap area in which colors are overlapped between respective colored pixels are required for the color filter.

As a method for producing such a color filter, a photolitho method has been often employed. The photolitho method is a method in which a colored radiation-sensitive composition is coated on a support and dried to form a colored layer and the colored layer is subjected to pattern exposure, development and the like to form a colored pixel of a first color (for example, green color), and then colored pixels of remaining colors are formed in the same manner as above.

For example, a technique is disclosed in JP-A-2009-65178 (the term "JP-A" as used herein means an "unexamined published Japanese patent application") in which reflectivity at 365 nm of a planarizing layer acting as a base layer for the colored pixel is controlled to 2% or less in order to provide a solid-state imaging device in which in a pixel size of 3.5 μιτι or less, moreover 3.0 um or less, variations in the pixel size and shape in color filter are considerably restrained to reduce influences on image quality and color unevenness, and generation of residue is considerably restrained to reduce influences on color unevenness.

Summary of Invention

However, along with the miniaturization of pixel in the solid-state imaging device, it becomes difficult for pattern formation by a conventional photolitho method to balance a spectral characteristic with a pattern-forming property of color filter toward the request for miniaturization and reduction in thickness of color filter.

In particular, in a color filter for solid-state imaging device, along with the reduction in thickness of organic pattern constituting the color filter, there is a tendency to seek the miniaturization so that, for example, the thickness is 1 μηι or less and the pixel size is 2 μπι or less (for example, from 0.5 to 2.0 μιτι). With the progress of miniaturization of color filter, since the influence of residue generated in the process of photolitho method on the image quality and color unevenness increases, a technique which can be significantly restrained the generation of residue has been requested.

The present invention has been made in view of the problems described above and an object of the invention is to provide a method for forming a cured layer or cured pattern which provides a layer which is excellent in strength as the layer itself and can be significantly restrained the generation of residue when used as a base layer of a colored film formed from a colored radiation-sensitive composition, a method for producing a color filter having an excellent spectral characteristic, and a color filter, solid-state imaging device and liquid crystal display device produced by using the method.

Another object of the invention is to provide a method for forming a cured layer or cured pattern which can lower heating temperature in heat curing, a method for producing a color filter having an excellent spectral characteristic, and a color filter, solid-state imaging device and liquid crystal display device produced by using the methods. In the production of color filter, the array order of pixels constituting the color filter can be appropriately set. However, in case of forming a color filter array having pixels of n kinds of colors by using the photolitho method described above, it is necessary to perform n times of coatings, exposures, developments and post-baking treatments, and a value obtained by n times integration of a defective rate occurred in the series of processes of coating, exposure, development and post-baking treatment results in contributing to a yield for production of the color filter array finally obtained.

In view of the above, as a result of intensive investigations, the inventor has hound particularly that development residue generated in the processes of forming a coating layer using a colored radiation-sensitive composition and exposing and developing the coating layer most contributes to the defective rate of color filter finally produced.

In particular, for example, in case of forming a colored film on a transparent film formed as a lower layer of color filter by using the nth colored radiation-sensitive composition and exposing and developing the colored film, colored residue derived from the nth colored radiation-sensitive composition generated in the unexposed area (which is an area where the nth colored film should be removed with a developer and an area for forming other colored pixel, for example, the (n + l)th colored pixel, the (n + 2)th colored pixel and the like in the processes performed later) influences to a transmission spectral characteristic of the other colored pixels described above to become a factor for increasing the device defective rate.

In order to efficiently remove the development residue in the unexposed area, an approach to optimize process conditions of development and rinse has been made, but it is rarely expected to achieve a drastic improvement.

In order to restrain the generation of residue, it is also considered to suppress the contents of photosensitive component and component of expressing a developing characteristic in the colored radiation-sensitive composition. In such a case, however, the amount of components necessary for the photolitho method decreases so that the problem is apt to occur that a pixel minimized in thickness and size is hardly formed in the desired shape (that is, a patterning characteristic becomes poor).

In view of the circumstances described above, the inventor has investigated on the development residue, the main cause of which is often considered to be the degree of alkali-solubility of a layer formed from a photosensitive composition, with drawing attention to a degree of curing (degree of polymerization) in a base layer for the layer formed from a photosensitive composition. As a result, in the case of using a method in which the base layer is formed from a photocurable composition and the exposure is performed with high exposure energy, diffusion of the exposure energy in the direction of the layer surface also increases and it is difficult to control the size of pixel finally obtained. On the contrary, however, it has been found that in the case where the base layer is formed from a heat-curable composition and heated in the state where oxygen concentration is controlled in a specific low range to perform curing, even when a coating layer is formed on the base layer using a photosensitive composition and the coating layer is exposed and developed, the generation of development residue can be dramatically restrained in the state of controlling the size of pixel.

The inventor has also found that by heating the coating layer formed using a heat-curable composition in the state where oxygen concentration is controlled in a specific low range as described above, the curing degree (polymerization degree) of the cured layer increases so that the strength of the cured layer itself can be improved.

The inventor has further found that in the situation where the curing degree (polymerization degree) of the cured layer to be requested is not so high, by heating the coating layer formed using a heat-curable composition in the state where oxygen concentration is controlled in a specific low range as described above, the heating temperature can be decreased lower than the conventional level and that this is extremely effective particularly in case of using a base material of low heat resistance as the base layer, thereby completing the invention.

Specifically, the invention includes the following items.

(1) A method for forming a cured layer or cured pattern, comprising: heating, in an environment where oxygen concentration is 100 ppm or less, a coating layer formed by coating a polymerizable composition containing a compound having a heat-polymerizable group on a substrate or a pattern formed by the coating layer.

(2) The method for forming a cured layer or cured pattern as described in (1) above, wherein the heating of coating layer or pattern is performed in a sealed heating tank in the presence of an inert gas.

(3) The method for forming a cured layer or cured pattern as described in (1) or (2) above, wherein the polymerizable composition is a transparent polymerizable composition.

(4) The method for forming a cured layer or cured pattern as described in any one of (1) to (3) above, wherein the polymerizable composition is a component further containing (i) a colorless transparent particle or (ii) at least any one of a colored pigment and a dye.

(5) The method for forming a cured layer or cured pattern as described in any one of (1) to (4) above, wherein the heat-polymerizable group is a radical polymerizable group.

(6) A method for producing a color filter comprising the method for forming a cured layer or cured pattern as described in any one of (1) to (5) above. (7) A color filter obtained by the method for producing a color filter as described in (6) above.

(8) A solid-state imaging device comprising the color filter as described in (7) above.

(9) A liquid crystal display device comprising the color filter as described in (7) above.

According to the invention, the configurations described below are preferred.

(10) A method for producing a color filter as described in (6) above wherein the coating layer is a transparent coating layer formed by coating a transparent polymerizable composition containing a compound having a heat-polymerizable group on a substrate and the transparent coating layer is heated in an environment where oxygen concentration of 100 ppm or less to form a transparent cured layer, and the method further comprises: coating (applying) a first colored radiation-sensitive composition onto the transparent cured layer to form a first colored radiation-sensitive layer; and exposing and developing the first colored radiation-sensitive layer to from a first colored pattern.

(11) The method for producing a color filter as described in (10) above wherein the first colored pattern is a pattern comprising a through-hole group comprising a first through-hole part group and a second through-hole part group formed in the first colored radiation-sensitive layer, and the method further comprises: stacking a second colored radiation-sensitive layer comprising a second colored radiation-sensitive composition on the first colored pattern so as that an inside of each through-hole of the first through-hole part group and second through-hole part group is filled with the second colored radiation-sensitive composition to form a plurality of second colored pixels; exposing and developing a position of the second colored radiation-sensitive layer corresponding to the first through-hole part group provided in the first colored layer to remove the second colored radiation-sensitive layer and the plurality of second colored pixels formed in the inside of each through-hole of the second through-hole part group provided in the first colored layer; stacking a third colored radiation-sensitive layer comprising a third colored radiation-sensitive composition on the first colored pattern so as that an inside of each through-hole of the second through-hole part group is filled with the third colored radiation-sensitive composition to form a plurality of third colored pixels; and exposing and developing a position of the third colored radiation-sensitive layer corresponding to the second through-hole part group provided in the first colored radiation-sensitive layer to remove the third colored radiation-sensitive layer.

(12) The method for producing a color filter as described in (11) above wherein the first colored radiation-sensitive composition is a composition containing a compound having a heat-polymerizable group, and the method further comprises heating the first colored pattern in an environment where oxygen concentration of 100 ppm or less before the stacking a second colored radiation-sensitive layer.

(13) The method for producing a color filter as described in (6) above wherein the pattern formed by the coating layer is a first colored pattern formed by exposing and developing a first colored radiation-sensitive layer formed by coating a first colored radiation-sensitive composition on the substrate and the first colored pattern is heated in an environment where oxygen concentration of 100 ppm or less to from a cured pattern, wherein the first colored pattern is a pattern comprising a through-hole group comprising a first through-hole part group and a second through-hole part group formed in the first colored radiation-sensitive layer, and the method further comprises: stacking a second colored radiation-sensitive layer comprising a second colored radiation-sensitive composition on the cured pattern so as that an inside of each through-hole of the first through-hole part group and second through-hole part group is filled with the second colored radiation-sensitive composition to form a plurality of second colored pixels; exposing and developing a position of the second colored radiation-sensitive layer corresponding to the first through-hole part group provided in the first colored layer to remove the second colored radiation-sensitive layer and the plurality of second colored pixels formed in the inside of each through-hole of the second through-hole part group provided in the first colored layer; stacking a third colored radiation-sensitive layer comprising a third colored radiation-sensitive composition on the first colored pattern so as that an inside of each through-hole of the second through-hole part group is filled with the third colored radiation-sensitive composition to form a plurality of third colored pixels; and exposing and developing a position of the third colored radiation-sensitive layer corresponding to the second through-hole part group provided in the first colored radiation-sensitive layer to remove the third colored radiation-sensitive layer. (14) The method for producing a color filter as described in any one of (11) to (13) above wherein the second colored radiation-sensitive composition is a composition containing a compound having a heat-polymerizable group, and the method further comprises heating the second colored pattern in an environment where oxygen concentration of 100 ppm or less before the stacking a third colored radiation-sensitive layer.

According to the present invention, a method for forming a cured layer or cured pattern which can form a layer which is excellent in strength as the layer itself and can be significantly restrained the generation of residue when used as a base layer of a colored film formed from a colored radiation-sensitive composition, a method for producing a color filter having an excellent spectral characteristic, and a color filter, solid-state imaging device and liquid crystal display device produced by using the methods can be provided.

Also, a method for forming a cured layer or cured pattern which can lower heating temperature in heat curing, a method for producing a color filter having an excellent spectral characteristic, and a color filter, solid-state imaging device and liquid crystal display device produced by using the methods can be provided. Brief Description of Drawing

Fig. 1 is a schematic cross-sectional view showing a configuration example of a color filter and a solid-state imaging device.

Fig. 2 is a schematic cross-sectional view showing a state in which a first colored radiation-sensitive layer is provided on a transparent cured layer.

Fig. 3 is a schematic cross-sectional view showing a state in which a first colored pattern is formed by forming a through-hole group in the first colored radiation-sensitive layer in Fig. 2.

Fig. 4 is a schematic cross-sectional view showing a state in which a second colored pattern and a second colored radiation-sensitive layer are formed.

Fig. 5 is a schematic cross-sectional view showing a state in which the second colored radiation-sensitive layer and a part of a second colored pixel constituting the second colored pattern in Fig. 4 are removed.

Fig. 6 is a schematic cross-sectional view showing a state in which a third colored pattern and a third colored radiation-sensitive layer are formed.

Fig. 7 is a schematic cross-sectional view showing a state in which the third colored radiation-sensitive layer in Fig. 6 is removed.

Fig. 8 is a view showing a result of measuring a green color pattern in Example 1 by a critical dimension scanning electron microscope.

Fig. 9 is a view showing a result of measuring a green color pattern in Comparative Example 1 by a critical dimension scanning electron microscope.

Fig. 10 is a view showing a result of measuring a blue color pattern in Example 2 by a critical dimension scanning electron microscope.

Fig. 11 is a view showing a relation between a wavelength and transmittance in a red cured layer before forming a blue radiation-sensitive layer and a relation between a wavelength and transmittance in a red region of a stack after forming a blue color pattern in Example 2.

Fig. 12 is a view showing a result of measuring a blue color pattern in Comparative Example 2 by a critical dimension scanning electron microscope.

Fig. 13 is a view showing a relation between a wavelength and transmittance in a red cured layer before forming a blue radiation-sensitive layer and a relation between a wavelength and transmittance in a red region of a stack after forming a blue color pattern in Comparative Example 2. [Description of reference numerals and signs]

10: Solid-state imaging device

11 : First colored radiation-sensitive layer 12: First colored pattern

13, 100: Color filter

14: Planarizing film

15: Microlens

20G Green color pixel (first colored pixel)

20R Red color pixel (second colored pixel)

20B Blue color pixel (third colored pixel)

21 : Second colored radiation-sensitive layer

22: Second colored pattern

31: Third colored radiation-sensitive layer

32: Third colored pattern

41: P well

42: Photo detector (photo diode)

43: Impurity diffusion layer

44: Electrode

45: Wiring layer

46: BPSG film

47: Insulating film

48: P-SiN film

49: Planarizing layer

60: Transparent cured layer

120: Through-hole group

121 : First through-hole part group

122: Second through-hole part group

Description of Embodiments

In the specification, with respect to the description of a group (atomic group), when the group is not indicated whether substituted or unsubstituted, the group includes the group which has a substituent as well as the group which does not have a substituent. For example, the description "an alkyl group" includes not only an alkyl group which does not have a substituent (an unsubstituted alkyl group) but also an alkyl group which has a substituent (a substituted alkyl group).

The description of the constituent element below is made based on the typical embodiment of the invention in some cases, but the invention should not be construed as being limited thereto. In the specification, a numerical value range represented by using the term "to" means a range which includes the numerical values described before and after the term "to" as a lower limit and an upper limit, respectively.

In the specification, the term "(meth)acrylate" represents acrylate and methacrylate, the term "(meth)acryl" represents acryl and methacryl, and the term "(meth)acryloyl" represents acryloyl and methacryloyl. The monomer in the invention is distinguished from an oligomer and a polymer and means a compound having a weight average molecular weight of 2,000 or less. In the specification, a polymerizable compound means a compound having a polymerizable group and may be a monomer or a polymer. The polymerizable group means a group involved in a polymerization reaction.

The term "radiation" as used in the invention means and includes visible light, an ultraviolet ray, a far ultraviolet ray, an electron beam, an X ray and the like.

The method for forming a cured layer or cured pattern according to the invention comprises heating a coating layer formed by coating a polymerizable composition containing a compound having a heat-polymerizable group on a substrate or a pattern formed by the coating layer in an environment where oxygen concentration of 100 ppm or less.

According to the method for forming a cured layer or cured pattern, the layer which is excellent in strength as the layer itself and can be significantly restrained the generation of residue when used as a base layer of a colored film formed from a colored radiation-sensitive composition can be provided. As a result, in the case of production of color filter by using the method for forming a cured layer or cured pattern, the color filter having an excellent spectral characteristic can be produced. The reason for this is not quite clear, but it is assumed as follows.

In the method for forming a cured layer or cured pattern according to the invention, the cured layer or cured pattern is formed by heating to cure a coating layer formed by coating a polymerizable composition containing a compound having a heat-polymerizable group on a substrate or a pattern formed by the coating layer in an environment where oxygen concentration of 100 ppm or less.

By performing the heat curing of the coating layer or pattern in the environment of extremely low oxygen concentration as described above, it is believed that the heat polymerization is not inhibited with oxygen and can be progressed at a very high efficiency in the coating layer or pattern. In other words, it is believed that the remaining amount of heat-polymerizable group derived from the compound having a heat-polymerizable group in the cured layer or cured pattern can be extremely reduced.

In the method for producing a color filter, it is assumed that the heat-polymerizable group in the coating layer or pattern is capable of reacting with an unreacted component in a colored radiation-sensitive layer formed on the coating layer or pattern and when the reaction described above proceeds for some reasons in a region which should be removed by development of the colored radiation-sensitive layer, a residue of the colored radiation-sensitive layer may be apt to remain on the cured layer or cured pattern even after the development.

According to the invention, however, since the remaining amount of heat-polymerizable group in the cured layer or cured pattern can be extremely reduced as described above, it is assumed that the reaction described above is inhibited, whereby the generation of development residue can be dramatically restrained. Also, according to the invention, since generation of development residue can be restrained as described above, it is believed that color mixing or the like with other colors can be inhibited, whereby the color filter having an excellent spectral characteristic can be produced.

Further, it is believed that since the heat polymerization is not inhibited with oxygen and can be progressed at a very high efficiency as described above, the curing degree (polymerization degree) of the cured layer or cured pattern increases, whereby the strength of the cured layer or cured pattern it self can be improved.

Moreover, according to the invention since the heat polymerization can be progressed at a very high efficiency as described above, in the situation where the curing degree (polymerization degree) of the cured layer or cured pattern to be requested is not so high, the heating temperature at time of formation of the cured layer or cured pattern (time of the heat curing) can be decreased and this is effective particularly in case of using a base material of low heat resistance as the base layer.

In particular, the method for forming a cured layer or cured pattern according to the invention is efficient for producing a color filter for solid-state imaging device required to be a minute size, for example, of 0.7 um or less in thickness and/or 2 um or less (for example, from 0.5 to 2.0 um) in pixel pattern size (length of one side of square pattern).

Therefore, the invention also relates to the method for producing a color filter including the method for forming a cured layer or cured pattern.

Now, as to the solid-state imaging device according to the embodiment of the invention, one example is briefly described with reference to Fig. 1.

As shown in Fig.l, a solid-state imaging device 10 is composed of a photo detector (photo diode) 42 provided on a silicon substrate, a color filter 13, a planarizing film 14, a microlens 15 and the like. According to the invention, the planarizing film 14 is not always necessarily provided. In Fig. 1 , in order to clarify each of the parts, the ratio between the thickness and width is disregarded and partly exaggerated.

As a support, in addition to the silicon substrate, any support used for a color filter may be employed without particular restriction. For instance, soda glass, borosilicate glass and quartz glass and those obtained by attaching a transparent conductive film thereto used for a liquid crystal display element or the like and a photoelectric conversion element substrate, for example, an oxidized film, silicon nitride used for a solid-state imaging element or the like are exemplified. Also, an intermediate layer or the like may be provided between the support and the color filter 13 so far as the advantage of the invention is not impaired.

On the silicon substrate is formed a P well 41 and the P well has a photodiode 42 in a portion of the surface thereof. The photodiode 42 is formed by ion-implantation of n-type impurity, for example, P or As and then conducting a heat treatment. Also, an impurity diffusion layer 43 having an n-type impurity concentration which is higher than that of the photodiode 42 is formed in a region of the surface of the P well 41 of silicon substrate which is different from the portion described above. The impurity diffusion layer 43 is formed by ion-implantation of n-type impurity, for example, P or As and then conducting a heat treatment and plays a role of a floating diffusion layer for transferring charges generated upon receiving incident light by the photodiode 42. In addition to use the composition wherein the well 41 functions as a p-type impurity layer and the photodiode 42 and the impurity diffusion layer 43 function as n-type impurity layers, a composition wherein the well 41 functions as an n-type impurity layer and the photodiode 42 and the impurity diffusion layer 43 function as p-type impurity layers can also be practiced.

On the P well 41, the photodiode 42 and the impurity diffusion layer 43, an insulating film 47 composed, for example, of Si0₂ or Si0₂/SiN/Si0₂ is formed. On the insulating film 47, an electrode 44 composed, for example, of poly Si, tungsten, tungsten silicide, Al or Cu is provided. The electrode 44 plays a role of a gate of a gate MOS transistor and can play a role of a transfer gate for transferring the charges generated in the photodiode 42 to the impurity diffusion layer 43. Above the electrode 44, further, a wiring layer 45 is formed. Above the wiring layer 45, further, a BPSG film 46 and P-SiN film 48 are formed. An interface between the BPSG film 46 and the P-SiN film 48 is formed in the form of curving downward above the photodiode 42, and plays a role of an intralayer lens for efficiently guiding incident light to the photodiode 42. On the BPSG film 46 is formed a planarizing layer 49 for the purpose of planarizing the surface of the P-SiN film 48 and irregular portions other than the pixel area.

On the planarizing layer 49 is formed a color filter 13. In the description below, a colored film formed on a silicon substrate without partitioning areas (a so-called solid film) is referred to as a "colored (colored radiation-sensitive) layer" and a colored film formed with partitioning areas into a pattern (for example, a film patterned in a stripe shape) is referred to as a "colored pattern". Also, of the colored patterns, a colored pattern (for example, a colored pattern patterned in a square shape or a rectangle shape) which is an element constituting the color filter 13 is referred to as a "colored (red color, green color or blue color) pixel".

The color filter 13 is constituted from a plurality of green color pixels (first colored pixels) 20G, red color pixels (second colored pixels) 20R and blue color pixels (third colored pixels) 20B two-dimensionally arrayed. The colored pixel 20R, 20G and 20B are formed at the position above the photo detectors 42, respectively. The green color pixel 20G is formed in a checkered pattern and the blue color pixel 20B and the red color pixel 20R are formed between the respective green color pixels 20G. In Fig. 1, for the purpose of explaining that the color filter 13 is constituted from the three color pixels, the colored pixel 20R, 20G and 20B are arranged in a row.

The planarizing film 14 is formed so as to cover above the color filter 13 to planarize a surface of the color filter.

The microlens 15 is a condenser lens arranged so as to direct the convex surface thereof upward and is provided above the planarizing film 14 (or the color filter when the planarizing film is not formed) and above the photo detectors 42. Each of the microlenses 15 efficiently guides light from the object to each of the photo detectors 42.

Next, the method for forming a cured layer or cured pattern according to the invention is described in detail with reference to a method for producing a color filter.

In the method of producing a color filter according to the embodiment of the invention, first of all, a transparent coating layer is formed by coating a transparent polymerizable composition containing a compound having a heat-polymerizable group on a substrate.

For example, in the case of producing a solid-state imaging device shown in Fig. 1, the transparent polymerizable composition is coated on P-SiN film 48 by a coating method, for example, a spin coating method, a slit coating method or a spray coating method, followed by drying to form the transparent coating layer.

The thickness of the transparent coating layer may be appropriately varied depending on the intended use and, for example, in case of using the transparent coating layer as a base layer (planarizing layer) of a color filter for solid-state imaging device, it is preferably in a range from 0.005 to 1 um, more preferably in a range from 0.01 to 0.8 um, and still more preferably in a range from 0.05 to 0.7 um.

Then, the transparent coating layer obtained as described above is heated in an environment where oxygen concentration of 100 ppm or less to form a transparent cured layer.

The environment where oxygen concentration of 100 ppm or less is preferably an environment where oxygen concentration of 50 ppm or less. In case of the environment where oxygen concentration of 100 ppm or less, the oxygen concentration is ordinarily 0.01 ppm or more. The heating method in the environment where oxygen concentration of 100 ppm or less is not particularly restricted so far as the low oxygen concentration can be achieved and, for example, a method in which a body to be heated having the transparent polymerizable layer is placed in a heating tank, the heating tank is sealed and then heated in the presence of inert gas by introducing the inert gas while exhausting air from the heating tank is preferred. The method can prevent the heating temperature from fluctuating.

Examples of the inert gas include nitrogen gas, argon gas and helium gas, and nitrogen gas is preferred.

The heating method in the environment where oxygen concentration of 100 ppm or less may also be a method in which a body to be heated having the transparent containing layer is placed in a heating tank, the heating tank is sealed, the air in the heating tank is exhausted, for example, by a vacuum pump to form a vacuum sate, and heating tank is heated under vacuum.

Examples of the heating device for performing the heating in the environment where oxygen concentration of 100 ppm or less include a hot plate and an oven.

In the case where the increase in strength of the layer itself and the restraint of the generation of residue are the main purposes, the heating temperature is preferably from 120 to 250°C, more preferably from 180 to 230°C, and particularly preferably from 200 to 220°C.

In the case where the decrease in the heating temperature at the time of formation of the cured layer or cured pattern (at the time of the heat curing) is the main purpose, the heating temperature is preferably from 120 to 180°C, more preferably from 120 to 160°C, and particularly preferably from 120 to 150°C. The heating time may vary depending on the heating means, and is ordinarily from about 1 to about 60 minutes, preferably from 1 to 10 minutes, and more preferably from 1 to 5 minutes.

In view of the above, the heating device is preferably a hot plate unit capable of providing a sealed space maintained at oxygen concentration of 100 ppm or less is preferred.

Since such a hot plate can be ordinarily installed into a semiconductor coater developer, there is an advantage in that the production efficiency of color filter is hardly impaired.

As described above, the transparent cured layer is formed by heating the transparent coating layer and, for example, in the case of producing the solid-state imaging device shown in Fig. 1, the transparent cured layer constitutes the planarizing layer 49.

Also, in the formation of transparent cured layer, a pre-curing treatment wherein the transparent coating layer is subjected to exposure with g-ray, i-ray, h-ray or the like, preferably with i-ray may be performed before the heating in an environment where oxygen concentration of 100 ppm or less. Then, as shown in the schematic cross-sectional view of Fig. 2, a first colored radiation-sensitive layer 11 is formed on the transparent cured layer 60 formed as described above (which corresponds to the planarizing layer 49 in the solid-state imaging device 10 shown in Fig. 1) by coating a first colored radiation-sensitive composition.

The formation of first colored radiation-sensitive layer 1 1 is performed by coating the first colored radiation-sensitive composition on a support by a coating method, for example, a spin coating method, a slit coating method or a spray coating method, followed by drying to from the colored layer.

The thickness of the first colored radiation-sensitive layer 11 is preferably in a range from 0.3 to 1 μιη, more preferably in a range from 0.35 to 0.8 μιη, and still more preferably in a range from 0.35 to 0.7 urn.

Next, a position 11A on the first colored radiation-sensitive layer 11 is exposed and developed to remove, for example, the unexposed area of first colored radiation-sensitive layer. As a result, a through-hole group 120 is formed in the first colored radiation-sensitive layer 11, whereby a first colored pattern 12 is formed (see the schematic cross-sectional view of Fig. 3).

The positions 11A are so determined that the through-hole group 120 is provided in a checkered pattern as viewed from above the first colored radiation-sensitive layer 11. Therefore, the first colored pattern 12 in which the through-hole group 120 is provided in the first colored radiation-sensitive layer 11 has plural first colored pixels of square shape in the checkered pattern.

Also, the through-hole group 120 has a first through-hole part group 121 and a second through-hole part group 122.

In the case where the first colored radiation-sensitive composition is a composition containing a compound having a heat-polymerizable group, it is preferred for heating the first colored pattern 12 to from a cured pattern.

The heating is performed preferably in the environment where oxygen concentration of 100 ppm or less, more preferably in the environment where oxygen concentration of 50 ppm or less (wherein the oxygen concentration is ordinarily 0.01 ppm or more) same as in the case of heating the transparent coating layer described above. The conditions of heating temperature, heating time, heating means and the like are same as those described with respect to the heating of transparent coating layer.

Thus, it is believed that the heat polymerization in the first colored pattern is not inhibited with oxygen and progresses at a very high efficiency. In other words, it is believed that the remaining amount of heat-polymerizable group derived from the compound having a heat-polymerizable group in the first colored pattern is extremely reduced. Therefore, in the case where for the purpose of forming the second or third colored pixel, a second or third colored radiation-sensitive composition is provided on the first colored pattern to form a second or third colored radiation-sensitive layer, followed by performing exposure and development as described hereinafter, a fear of the generation of residue resulting from a reaction between the heat-polymerizable group remaining in the first colored pattern and an unreacted component in the second or third colored radiation-sensitive composition can be restrained so that a color filter having more excellent spectral characteristic can be produced.

Then, as shown in the schematic cross-sectional view of Fig. 4, a second colored radiation-sensitive layer 21 is stacked using a second colored radiation-sensitive composition on the colored pattern 12 having the through-hole group 120 formed in the first colored radiation-sensitive layer 11 so as that an inside of each through-hole of the first through-hole part group 121 and second through-hole part group 122 is filled with the second colored radiation-sensitive composition to form a plurality of second colored pixels. Thus, a second colored pattern 22 having the plurality of second colored pixels is formed in the through-hole group 120 in the first colored radiation-sensitive layer 11. The second colored pixel is a pixel having a square shape. The formation of the second colored radiation-sensitive layer 21 can be carried out in the same manner as in the method of forming the first colored radiation-sensitive layer 11 described above.

The thickness of the second colored radiation-sensitive layer 21 is preferably in a range from 0.3 to 1 um, more preferably in a range from 0.35 to 0.8 um, and still more preferably in a range from 0.35 to 0.7 um.

Then, a position 21 A of the second colored radiation-sensitive layer 21 corresponding to the first through-hole part group 121 provided in the first colored radiation-sensitive layer 1 1 is exposed and developed to remove the second colored radiation-sensitive layer 21 and the plurality of second colored pixels 22R formed in the inside of each through-hole of the second through-hole part group 122 are removed (see the schematic cross-sectional view of Fig. 5).

In the case where the second colored radiation-sensitive composition is a composition containing a compound having a heat-polymerizable group, it is preferred that the second colored pixel is heated by a heating device, for example, a hot plate or an oven to cure. The heating temperature is preferably from 120 to 250°C, and more preferably from 160 to 230°C. The heating time may vary depending on the heating means, and is ordinarily from about 3 to about 30 minutes in case of heating on a hot plate, or ordinarily from about 30 to about 90 minutes in case of heating in an oven.

Thus, it is believed that the heat polymerization in the second colored pixel is not inhibited with oxygen and progresses at a very high efficiency. In other words, it is believed that the remaining amount of heat-polymerizable group derived from the compound having a heat-polymerizable group in the second colored pixel is extremely reduced.

Therefore, in the case where for the purpose of forming the third colored pixel, a third colored radiation-sensitive composition is provided on the first colored pattern where the second colored pattern having the second colored pixel is formed in the first through-hole part group to form a third colored radiation-sensitive layer, followed by performing exposure and development as described hereinafter, a fear of the generation of residue resulting from a reaction between the heat-polymerizable group remaining in the second colored pixel and a photosensitive component in the third colored radiation-sensitive composition can be restrained so that a color filter having more excellent spectral characteristic can be produced.

Then, as shown in the schematic cross-sectional view of Fig. 6, a third colored radiation-sensitive layer 31 is formed using a third colored radiation-sensitive composition on the first colored pattern 12 where the second colored pattern 22 is formed in the first through-hole part group 121 so as that an inside of each through-hole of the second through-hole part group 122 is filled with the third colored radiation-sensitive composition to form a plurality of third colored pixels. Thus, a third colored pattern 32 having the plurality of third colored pixels is formed in the second through-hole part group 122 in the first colored layer 11. The third colored pixel is a pixel having a square shape. The formation of the third colored radiation-sensitive layer 31 can be carried out in the same manner as in the method of forming the first colored radiation-sensitive layer 11 described above.

The thickness of the third colored radiation-sensitive layer 31 is preferably in a range from 0.3 to 1 μηι, more preferably in a range from 0.35 to 0.8 μπι, and still more preferably in a range from 0.35 to 0.7 um.

Then, a position 31A of the third colored radiation-sensitive layer 31 corresponding to the second through-hole part group 122 provided in the first colored radiation-sensitive layer 11 is exposed and developed to remove the third colored radiation-sensitive layer 31, whereby, as shown in the schematic cross-sectional view of Fig. 7, a color filter 100 having the first colored pattern 12, the second colored pattern 22 and the third colored pattern 32 is produced. Although the method of producing a color filter according to the embodiment of the invention is described above, an embodiment wherein the heating of transparent coating layer is not performed in the environment where oxygen concentration of 100 ppm or less in the embodiment described above, but as the first colored radiation-sensitive composition, a composition containing a compound having a heat-polymerizable group is used, the first colored pattern formed from the first colored radiation-sensitive composition is heated in the environment where oxygen concentration of 100 ppm or less to from a cured pattern, and on the cured pattern is stacked the second colored radiation-sensitive layer composed of the second colored radiation-sensitive composition is also suitable for the method of producing a color filter according to the embodiment of the invention.

Further, the generation of development scum can be restrained in an embodiment wherein on a base layer (for example, a silicon substrate) which does not fall into the cured layer formed using a polymerizable compound (for example, the transparent cured layer formed by heating of the transparent coating layer described in the embodiment above) is formed the first colored pattern using the first colored radiation-sensitive composition in the manner as described above, the first colored pattern is heated in the environment where oxygen concentration of 100 ppm or less to from a cured pattern, and on the cured pattern is stacked the second colored radiation-sensitive layer composed of the second colored radiation-sensitive composition.

The reason for this is believed to be, first, that since the heat polymerization can be progressed at a very high efficiency in the first colored pattern by heating the first colored pattern in the environment where oxygen concentration of 100 ppm or less, the remaining amount of heat-polymerizable group in the first colored pattern can be extremely reduced so that the reaction between the surface portion of first colored pattern and an unreacted component in the second colored radiation-sensitive composition can be restrained, and as a result when the second colored radiation-sensitive layer is exposed and developed, the unexposed area of the second colored radiation-sensitive layer is surely removed with a developer.

Further, at the time of forming the first colored pattern (that is, at the time of development of the first colored radiation-sensitive layer), the unreacted material (mostly the transparent resin) derived from the first colored radiation-sensitive layer remains without being removed with the developer in the region where the first colored pattern is not formed (that is, the region where the surface of base layer is revealed) in some cases. However, according to the invention, it is believed to be that since not only the first colored pattern but also the unreacted material is formed through the heating in an environment where oxygen concentration of 100 ppm or less, the degree of progress of heat polymerization is high in the unreacted material so that the unreacted material in which the remaining amount of the heat-polymerizable group is small is formed and as a result, when the second colored radiation-sensitive layer is formed using the second colored radiation-sensitive composition on the first colored pattern, for example, a reaction between the unreacted material in the second colored radiation-sensitive composition and the unreacted material remaining in the region where the first colored pattern is not formed can be inhibited so that the generation of development scum can also be restrained in the region where the first colored pattern is not formed. [Polymerizable composition]

The polymerizable composition for obtaining the coating layer or pattern formed from the coating layer which is subjected to the heating step in an environment where oxygen concentration of 100 ppm or less in the method for forming a cured layer or cured pattem according to the invention contains a compound having a heat-polymerizable group.

In the case where the coating layer or pattem formed from the coating layer is a transparent coating layer or transparent pattern, the polymerizable composition is ordinarily a transparent polymerizable composition.

In the case where the coating layer or pattern formed from the coating layer is a colored coating layer or colored pattem, the polymerizable composition is ordinarily a colored radiation-sensitive composition.

The polymerizable composition is preferably a composition further containing (i) a colorless transparent particle or (ii) at least any one of a colored pigment and a dye. In the case where the polymerizable composition is the transparent polymerizable composition, an embodiment containing (i) a colorless transparent particle is preferred, and in the case where the polymerizable composition is the colored radiation-sensitive composition, an embodiment containing (ii) at least any one of a colored pigment and a dye is preferred.

The details of the compound having a heat-polymerizable group and other components and the preferred range of content of each component are same as those described in the transparent polymerizable composition below.

[Transparent polymerizable composition]

The transparent polymerizable composition is described in detail below.

-Polymerizable compound having heat-polymerizable group-

The transparent polymerizable composition according to the invention contains a polymerizable compound having a heat-polymerizable group.

The heat-polymerizable group is preferably a radical polymerizable group, and the radical polymerizable group suitably includes an ethylenically unsaturated bond group.

Specifically, the polymerizable compound is preferably selected from compounds having at least one ethylenically unsaturated bond group, preferably two or more ethylenically unsaturated bond groups. Such compounds are widely known in the field of art and these compounds can be used without any particular restriction in the invention. The compound may be in any of chemical forms, for example, a monomer, a prepolymer, specifically, a dimer, a trimer or an oligomer, a mixture thereof or a multimer thereof. The polymerizable compounds according to the invention may be used individually or in combination of two or more thereof.

More specifically, examples of the monomer and prepolymer thereof include an unsaturated carboxylic acid (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid or maleic acid), its esters and amides, and multimers thereof. An ester of an unsaturated carboxylic acid and an aliphatic polyhydric alcohol compound, an amide of an unsaturated carboxylic acid and an aliphatic polyvalent amine compound, and multimers thereof are preferred. Also, an addition reaction product of an unsaturated carboxylic acid ester or amide having a nucleophilic substituent, for example, a hydroxy group, an amino group or a mercapto group, with a monofunctional or polyfunctional isocyanate or epoxy compound, and a dehydration condensation reaction product of an unsaturated carboxylic acid ester or amide having a nucleophilic substituent with a monofunctional or polyfunctional carboxylic acid may be also suitably used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent, for example, an isocyanate group or an epoxy group, with a monoiunctional or polyfunctional alcohol, amine or thiol, and a substitution reaction product of an unsaturated carboxylic acid ester or amide having a releasable substituent, for example, a halogen atom or a tosyloxy group, with a monofunctional or polyfunctional alcohol, amine or thiol are also suitable. As other examples, compounds where the unsaturated carboxylic acid described above is replaced by an unsaturated phosphonic acid, a vinylbenzene derivative, for example, styrene, vinyl ether, allyl ether or the like may be also used.

As to specific examples of the compound, compounds described in Paragraph Nos. [0095] to [0108] of JP-A-2009-288705 may be suitably used also in the invention.

As the polymerizable compound, a compound having an ethylenically unsaturated group which contains at least one addition-polymerizable ethylene group and has a boiling point of 100°C or more under normal pressure is also preferred as a polymerizable monomer. Examples thereof include a monoiunctional acrylate or methacrylate, for example, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate or phenoxyethyl (meth)acrylate; a polyfunctional acrylate or methacrylate, for example, polyethylene glycol di(meth)acrylate, trimethylolethane tri(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, hexanediol (meth)acrylate, trimethylolpropane tri(acryloyloxypropyl)ether, tri(acryloyloxyethyl)isocyanurate, a compound obtained by adding ethylene oxide or propylene oxide to a polyfunctional alcohol, for example, glycerin or trimethylolethane, followed by (meth)acrylation, an urethane (meth)acrylate as described in JP-B-48-41708 (the term "JP-B" as used herein means an "examined Japanese patent publication"), JP-B-50-6034 and JP-A-51-37193, a polyester acrylate described in JP-A-48-64183, JP-B-49-43191 and JP-B-52-30490, and an epoxy acrylate as a reaction product of an epoxy resin and (meth)acrylic acid; and a mixture thereof.

A polyfunctional (meth)acrylate obtained by reacting a polyfunctional carboxylic acid with a compound having a cyclic ether group and an ethylenically unsaturated group, for example, glycidyl (meth)acrylate is also exemplified.

As other preferred polymerizable compounds, compounds having a fluorene ring and two or more ethylenically unsaturated groups described in JP-A-2010-160418, JP-A-2010-129825 and Japanese Patent No. 4,364,216, and a cardo resin may also be used.

As the compound which has a boiling point of 100°C or more under normal pressure and contains at least one addition-polymerizable ethylenically unsaturated group, compounds described in Paragraph Nos. [0254] to [0257] of JP-A-2008-292970 are also suitable.

In addition, radical polymerizable monomers represented by formulae (MO-1) to (MO-5) shown below may be suitably used. In the formulae, when T is an oxyalkylene group, the oxyalkylene group is connected to R at its terminal on the carbon atom side.

(M0-1)

CH₃

H₂C =CH -C-0 H C=C C o

I I II

O O

0 -C -(CH₂)_t— C- 0-C-NH-(CH₂)m-C-OH OH

I I II I I II

O O O O

-CH 3

T : *— (CH₂)_r— * — OCH₂- — OCH₂CH₂- OGH2CH 2CH2-" OCH2CH2CH2GH2

-0(CO) -(CH₂)m— , -COO— (CH₂)m— -OGH ( GH ₃) -CH ₂— -OCH₂CH(CH₃) -

I■ -O - _! -O -C -NH— (CH₂)n -NH -C O -

O O

In the formulae above, n is from 0 to 14 and m is from 1 to 8. When plural Rs or plural Ts are present in one molecule, plural Rs or plural Ts may be the same or different from each other.

In each of the radical polymerizable monomers represented by formulae (MO-l) to (MO-5), at least one of plural Rs represents a group represented by -OC(=0)CH=CH₂ or -OC(=0)C(CH₃)=CH₂.

As to specific examples of the radical polymerizable monomers represented by formulae (MO-1) to (MO-5), compounds described in Paragraph Nos. [0248] to [0251] of JP-A-2007-269779 may also be suitably used in the invention.

Compounds obtained by adding ethylene oxide or propylene oxide to the above-described polyfunctional alcohol and then (meth)acrylating the adduct, represented by formulae (1) and (2) described together with their specific examples in JP-A- 10-62986 may also be used as the polymerizable compound.

Among them, preferred polymerizable compounds include RP 1040 (produced by Nippon Kayaku Co., Ltd.), dipentaerythritol triacrylate (as a commercial product, KAYARAD D-330, produced by Nippon Kayaku Co., Ltd.), dipentaerythritol tetraacrylate (as a commercial product, KAYARAD D-320, produced by Nippon Kayaku Co., Ltd.), dipentaerythritol penta(meth)acrylate (as a commercial product, KAYARAD D-310, produced by Nippon Kayaku Co., Ltd.), dipentaerythritol hexa(meth)acrylate (as a commercial product, KAYARAD DPHA, produced by Nippon Kayaku Co., Ltd.), and structures where the (meth)acryloyl group of the compounds described above are connected through an ethylene glycol or propylene glycol residue. Oligomer types of these compounds may also be used.

The polymerizable compound may be a polyfunctional monomer having an acid group, for example, a carboxyl group, sulfonic acid group or phosphoric acid group. Therefore, when the ethylenic compound has an unreacted carboxyl group as in the case of the mixture described above, it may be utilized as it is but, if desired, a non-aromatic carboxylic anhydride may be reacted with a hydroxy group of the ethylenic compound to introduce an acid group. In this case, specific examples of the non-aromatic carboxylic anhydride include tetrahydrophthalic anhydride, an alkylated tetrahydrophthalic anhydride, hexahydrophthalic anhydride, an alkylated hexahydrophthalic anhydride, succinic anhydride and maleic anhydride.

In the invention, the acid group-containing monomer is preferably a polyfunctional monomer which is an ester of an aliphatic polyhydroxy compound and an unsaturated carboxylic acid and obtained by reacting a non-aromatic carboxylic anhydride with an unreacted hydroxyl group of the aliphatic polyhydroxy compound to introduce the acid group, and particularly preferably the ester described above where the aliphatic polyhydroxy compound is pentaerythritol and/or dipentaerythritol. Examples of the commercial product thereof include polybasic acid-modified acryl oligomers M-510 and M-520 produced by Toagosei Co., Ltd.

One of the monomers may be used alone, but since it is difficult to use a single compound in view of production, two or more monomers may be used as a mixture. Also, as the monomer, a polyfunctional monomer having no acid group and a polyfunctional monomer having an acid group may be used in combination, if desired.

The acid value of the polyfunctional monomer having an acid group is preferably from 0.1 to 40 mg-KOH/g, and particularly preferably from 5 to 30 mg-KOH/g. When the acid value of the polyfunctional monomer is too low, the development dissolution characteristic decreases, whereas when the acid value of the polyfunctional monomer is too high, the production or handling thereof becomes difficult, the photopolymerization performance decreases and the curing property, for example, surface smoothness of pixel deteriorates. Therefore, in the case where two or more polyfunctional monomers having different acid groups are used in combination or in the case where a polyfunctional monomer having no acid group is used in combination, it is essential to adjust the acid value as the total polyfunctional monomer falls within the range described above.

Also, it is a preferred to contain a polyfunctional monomer having a caprolactone structure as the polymerizable monomer.

The polyfunctional monomer having a caprolactone structure is not particularly restricted so far as it has a caprolactone structure in the molecule thereof, and includes, for example, an ε-caprolactone-modified polyfunctional (meth)acrylate obtained by esterification of a polyhydric alcohol, for example, trimethylolethane, ditrimethylolethane, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, glycerol, diglycerol or trimethylolamine with (meth)acrylic acid and ε-caprolactone. Among them, a polyfunctional monomer having a caprolactone structure represented by formula (1) shown below is preferred.

In formula (1), all of six Rs are groups represented by formula (2) shown below, or one to five of six Rs are groups represented by formula (2) shown below and the reminder is a group represented by formula (3) shown below.

In formula (2), R¹ represents a hydrogen atom or a methyl group, m represents a number of 1 or 2, and * represents a connecting portion.

In formula (3), R¹ represents a hydrogen atom or a methyl group and * represents a connecting portion.

The polyfunctional monomer having a caprolactone structure is commercially available as KAYARAD DPCA Series from Nippon Kayaku Co., Ltd. and includes DPCA-20 (compound represented by formulae (1) to (3), wherein m is 1, a number of the groups represented by formula (2) is 2, and all of R¹ are hydrogen atoms), DPCA-30 (compound represented by formulae (1) to (3), wherein m is 1, a number of the groups represented by formula (2) is 3, and all of R¹ are hydrogen atoms), DPCA-60 (compound represented by formulae (1) to (3), wherein m is 1, a number of the groups represented by formula (2) is 6, and all of R¹ are hydrogen atoms) and DPCA-120 (compound represented by formulae (1) to (3), wherein m is 2, a number of the groups represented by formula (2) is 6, and all of R¹ are hydrogen atoms).

The polyfunctional monomers having a caprolactone structure may be used individually or as a mixture of two or more thereof in the invention.

It is also preferred that the polyfunctional monomer for use in the invention is at least one compound selected from the group consisting of compounds represented by formulae (i) and (ii) shown below.

In formulae (i) and (ii), E each independently represents -((CH₂)_yCH₂0)- or -((CH₂)_yCH(CH₃)0)-, y each independently represents an integer from 0 to 10, and X each independently represents an acryloyl group, a methacryloyl group, a hydrogen atom or a carboxyl group.

In formula (i), the total number of acryloyl groups and methacryloyl groups is 3 or 4, m each independently represents an integer from 0 to 10, and the total of each m is an integer from 0 to 40, provided that when the total of each m is 0, any one of Xs is a carboxyl group.

In formula (ii), the total number of acryloyl groups and methacryloyl group is 5 or 6, n each independently represents an integer from 0 to 10, and the total of each n is an integer from 0 to 60, provided that when the total of each n is 0, any one of Xs is a carboxyl group.

In formula (i), m is preferably an integer from 0 to 6, and more preferably an integer from 0 to 4. The total of each m is preferably an integer from 2 to 40, more preferably an integer from 2 to 16, and particularly preferably an integer from 4 to 8.

In formula (ii), n is preferably an integer from 0 to 6, and more preferably an integer from 0 to 4. The total of each n is preferably an integer from 3 to 60, more preferably an integer from 3 to 24, and particularly preferably an integer from 6 to 12. In a preferred embodiment, -((CH₂)_yCH₂0)- or -((CH₂)_yCH(CH₃)0)- in formula (i) or (ii) is connected to X at its terminal on the oxygen atom side.

The compounds represented by formulae (i) and (ii) may be used individually or in combination of two or more thereof. In particular, an embodiment where all of six Xs in formula (ii) are acryloyl groups is preferred.

The total content of the compound represented by formula (i) or (ii) in the polymerizable compound is preferably 20% by weight or more, and more preferably 50% by weight or more.

The compound represented by formula (i) or (ii) can be synthesized through a process of connecting a ring-opened skeleton of ethylene oxide or propylene oxide to pentaerythritol or dipentaerythritol by a ring-opening addition reaction, and a process of introducing a (meth)acryloyl group into the terminal hydroxyl group of the ring-opened skeleton by reacting, for example, (meth)acryloyl chloride, which are conventionally known processes. Each process is a well-known process and the compound represented by formula (i) or (ii) can be easily synthesized by a person skilled in the art.

Of the compounds represented by formulae (i) and (ii), a pentaerythritol derivative and/or a dipentaerythritol derivative are more preferred.

Specific examples of the compounds include compounds represented by formulae (a) to (f) shown below (hereinafter, also referred to as Compounds (a) to (f) sometimes), and Compounds (a), (b), (e) and (f) are preferred.

(total of each n is 6)

(b)

(total of each n is 12)

(total of each n is 6)

(total of each m is 4)

(total of each m is 12)

Examples of commercial product of the polymerizable compounds represented by formulae (i) and (ii) include SR-494, which is a tetrafunctional acrylate having four ethyleneoxy chains, produced by Sartomer Company, and DPCA-60, which is a hexafiinctional acrylate having six pentyleneoxy chains and TPA-330, which is a trifunctional acrylate having three isobutyleneoxy chains, both produced by Nippon Kayaku Co., Ltd.

Furthermore, urethane acrylates as described in JP-B-48-41708, JP-A-51-37193, JP-B-2-32293 and JP-B-2- 16765, and urethane compounds having an ethylene oxide skeleton described in JP-B-58-49860, JP-B-56- 17654, JP-B-62-39417 and JP-B-62-39418 are also suitable as the polymerizable compound. In addition, by using as the polymerizable compound, an addition-polymerizable compound having an amino structure or a sulfide structure in the molecule thereof described in JP-A-63-277653, JP-A-63 -260909 and JP-A-1- 105238, a curable composition very excellent in photosensitive speed can be obtained.

Examples of commercial product of the polymerizable compound include urethane oligomers UAS-10 and UAB-140 (produced by Sanyo Kokusaku Pulp Co., Ltd.), UA-7200 (produced by Shin-Nakamura Chemical Co., Ltd.), DPHA-40H (produced by Nippon Kayaku Co., Ltd.), UA-306H, UA-306T, UA-306I, AH-600, T-600 and AI-600 (produced by Kyoeisha Chemical Co., Ltd.).

Further, ethylenically unsaturated compounds having an acid group are also suitable for the polymerizable compound. The ethylenically unsaturated compound having an acid group is obtained, for example, by a method wherein partial hydroxy groups of the polyhydric alcohol described above are (meth)acrylated and the remaining hydroxy groups are subjected to an addition reaction with an acid anhydride to from a carboxy group. Examples of commercial product thereof include polybasic acid-modified acryl oligomers M-510 and M-520 (produced by Toagosei Co., Ltd.).

As to the polymerizable compound, details of the method of using thereof, for example, the structure thereof, individual or combination use or the amount thereof added can be appropriately determined in accordance with the final characteristic design of the transparent polymerizable composition. For example, from the standpoint of sensitivity, a structure having a large unsaturated group content per molecular is preferred, and in many cases, a difunctional or higher functional structure is preferred. From the standpoint of increasing the strength of transparent cured film, a Afunctional or higher functional compound is preferred. Further, a method of using compounds having different numbers of functional groups or different polymerizable groups (for example, an acrylate, a methacrylate, a styrene compound or a vinyl ether compound) in combination to control both the sensitivity and the strength is also effective. Moreover, a combination use of Afunctional or higher functional polymerizable compounds having different ethylene oxide chain length is preferred because the development property of transparent polymerizable composition can be adjusted and the excellent pattern forming ability can be obtained. Furthermore, the selection and use method of the polymerizable compound are also important factors for the compatibility and dispersibility with other components (for example, a photopolymerization initiator, a colorless transparent particle or a binder polymer) contained in the transparent polymerizable composition. For example, the compatibility can be sometimes improved by using a low-purity compound or using two or more kinds of the compounds in combination. Also, a specific structure may be selected for the purpose of improving the adhesion property to a hard surface of a support or the like.

The content of the polymerizable compound having a heat-polymerizable group in the transparent polymerizable composition according to the invention is preferably from 0.1 to 100% by weight, more preferably from 1.0 to 80% by weight, particularly preferably from 2.0 to 70% by weight, based on the solid content of the transparent polymerizable composition.

Further, in the case where the transparent polymerizable composition contains a colorless transparent particle described in detail below, a weight ratio of the colorless transparent particle and the polymerizable compound having a heat-polymerizable group is preferably from 1 : 2 to 20 : 1, more preferably from 1 : 1 to 10 : 1, from the standpoint of reduction in thickness.

Polyfunctional thiol compounds having two or more mercapto (SH) groups in their molecules may be used with the polymerizable compound. In particular, compounds represented by formulae (I) shown below are preferred.

1 2 (

In formula (I), R represents an alkylene group, R represents an n-valent linking group, R represents an alkyl group, and n represents an integer from 2 to 4.

Specific examples of the polyfunctional thiol compound represented by formula (I) include l,4-bis(3-mercaptobutyryloxy)butane (represented by formula (II)),

l,3,5-tris(3-mercaptobutyloxyemyl)-l,3,5-triazine-2,4,6(lH,3H,5H)trione (represented by formula (III)) and pentaerythritol tetrakis(3-mercaptobutylate) (represented by formula (IV)). The polyfunctional thiol compounds may be used individually or in combination of two or more thereof.

The amount of the polyfunctional thiol compound added to the transparent polymerizable composition is preferably from 0.3 to 8.9% by weight, more preferably from 0.8 to 6.4% by weight, based on the total solid content exclusive of solvent of the composition. By the addition of polyfunctional thiol compound, the stability, odor, sensitivity, resolution, development property, adhesion property and the like of the transparent polymerizable composition can be improved.

-Heat-crosslinking agent-

The transparent polymerizable composition according to the invention may contain a compound having a heat-crosslinking group (hereinafter, also referred to as a heat-crosslinking agent. The heat-crosslinking agent is preferably that having at least one group selected from an epoxy group, a methylol group, an alkoxymethyl group and an acyloxymethyl group.

More preferred examples of the heat-crosslinking agent include (a) an epoxy compound, (b) a melamine compound, guan amine compound, glycoluril compound or urea compound substituted with at least one substituent selected from a methylol group, an alkoxymethyl group and an acyloxymethyl group, and (c) a phenol compound, naphthol compound or hydroxyanthracene compound substituted by at least one substituent selected from a methylol group, an alkoxymethyl group and an acyloxymethyl group. Among them, a polyfunctional epoxy compound is particularly preferred as the heat-crosslinking agent.

The total content of the heat-crosslinking agent in the transparent polymerizable composition may be varied depending on the material, and is preferably from 0.1 to 50% by weight, more preferably from 0.2 to 40% by weight, particularly preferably from 1 to 35% by weight, based on the total solid content of the transparent polymerizable composition.

-Various additives-

The transparent polymerizable composition according to the invention may contain various additives, for example, a binder, a curing agent, a curing catalyst, a solvent, a filler, a polymer compound other than described above, a polymerization initiator, a surfactant, an adhesion accelerator, an antioxidant, an ultraviolet absorbing agent, a coagulation preventing agent or a dispersing agent, if desired, within the range where the effects of the invention are not impaired. -Binder-

The binder may or may not have alkali solubility and it is sufficient to be soluble in an organic solvent and to have performance of maintaining dispersion stability and curing property.

The binder is preferably a linear organic polymer and soluble in an organic solvent. Examples of such a linear organic polymer include a polymer having a carboxylic acid group in its side chain, for example, a methacrylic acid copolymer, an acrylic acid copolymer, an itaconic acid copolymer, a crotonic acid copolymer, a maleic acid copolymer, a partially esterified maleic acid copolymer as described in JP-A-59-44615, JP-B-54-34327, JP-B-58-12577, JP-B-54-25957, JP-A-59-53836 and JP-A-59-71048. Also, an acidic cellulose derivative having a carboxylic acid group in its side chain is useful.

Of the binders, a polyhydroxystyrene resin, a polysiloxane resin, an acrylic resin, an acrylamide resin or an acryl/acrylamide copolymer resin is preferred from the standpoint of heat resistance, and an acrylic resin, an acrylamide resin or an acryl/acrylamide copolymer resin is more preferred from the standpoint of controlling the development property.

As the acrylic resin, a copolymer comprising a monomer selected, for example, from benzyl (meth)acrylate, (meth)acrylic acid, hydroxyethyl (meth)acrylate and (meth)acrylamide, for example, benzyl methacrylate/methacrylic acid copolymer, benzyl methacrylate benzylmethacrylamide copolymer, KS RESIST- 106 (produced by Osaka Organic Chemical Industry Ltd.), CYCLOMER P Series (produced by Daicel Chemical Industries, Ltd.) or ACA230AA (produced by Daicel Chemical Industries, Ltd.) is preferred.

-Curing agent- In the case where as the heat-crosslinking agent, for example, an epoxy compound is used, a curing agent is preferably added. Since the curing agent for epoxy compound has a wide variety of kinds, and the property, usable time of a mixture of the epoxy compound and curing agent, viscosity, curing temperature, curing time, heat generation and the like are widely varied depending on the kind of the curing agent used, it is required to select an appropriate curing agent depending on the intended use, conditions for use and operation conditions of the curing agent. With respect to the curing agent, detailed explanations are made in Hiroshi Kakiuchi ed., Epoxy Jushi (Epoxy Resin), Chapter 5 (Shoukoudo). Examples of the curing agent are shown below.

Examples of the curing agent acting catalytically include a tertiary amine and a boron trifluoride-amine complex; examples of the curing agent reacting stoichiometrically with a functional group of the epoxy compound include a polyamine and an acid anhydride; examples of the curing agent of normal temperature curing type include diethylenetriamine and a polyamide resin, examples of the curing agent of medium temperature curing type include diemylaminopropylamine and tris(dimethylaminomethyl)phenol; and examples of the curing agent of high temperature curing type include phthalic anhydride and metaphenylenediamine. According to the classification based on the chemical structure, with respect to an amine, examples of an aliphatic polyamine include diethylenetriamine; examples of an aromatic polyamine include metaphenylenediamine; examples of a tertiary amine include tris(dimethylaminomethyl)phenol; examples of an acid anhydride include phthalic anhydride, a polyamide resin, a polysulfide resin and boron trifiuoride-monoethylamine complex; examples of a synthetic resin precondensate include a phenolic resin; and examples of others include dicyandiamide.

The curing agent is reacted with a heat-crosslinking group of the heat-crosslinking agent (for example, an epoxy group of the epoxy compound) by heating and polymerized to increase in crosslink density, thereby curing. Both the binder and the curing agent are preferably used in amounts as small as possible for the purpose of achieving the reduction in thickness, and particularly, with respect to the curing agent the amount thereof is 35% by weight or less, preferably 30% by weight or less, still more preferably 25% by weight or less, to the heat-crosslinking agent.

-Curing catalyst-

In addition to the curing by the reaction with the curing agent, curing by reaction of the epoxy groups mainly with each other is also effective. Thus, a curing catalyst may be used without using the curing agent. With respect to the amount of the curing catalyst added, it is possible to cure in a slight amount as approximately from 1/10 to 1/1,000, preferably approximately from 1/20 to 1/500, more preferably approximately from 1/30 to 1/250, on a weight basis of an epoxy compound having epoxy equivalent of approximately from 150 to 200. -Solvent-

The transparent polymerizable composition according to the invention can be used as a solution prepared by dissolving the composition in various solvents. The solvent which can be used in the transparent polymerizable composition according to the invention is basically not particularly restricted so far as the solubility of each component and the coating property of the transparent polymerizable composition are satisfied.

-Colorless transparent particle-

The transparent polymerizable composition according to the invention may contain a colorless transparent particle.

The colorless transparent particle is not particularly restricted and is preferably an inorganic fine particle. For example, in the case where the refractive index for light at a wavelength of 633 nm of the transparent cured film or transparent cured pattern finally obtained is desired to fall in the range from 1.60 to 1.90, the inorganic fine particle is preferably an oxide of one member or two or more members selected from the group consisting of Si, Ti, Zr, Al and Sn, more preferably an oxide of one member or two or more members selected from Ti, Al and Sn, and still more preferably an oxide of one member or two members selected from Ti and Al.

Specific examples of the oxide include Ti0₂, A1₂0₃, Si0₂, SnO and Sn0₂.

The production method of the inorganic fine particle is described, for example, in JP-A-10-81517 and JP-A-2001-26423.

The colorless transparent particle preferably has an average particle size from 1 to 200 nm, and more preferably from 10 to 100 nm.

The average particle size of the colorless transparent particle can be determined from a photograph obtained by observing dispersed particles through a transmission electron microscope. The projected area of a particle is measured, the equivalent-circle diameter is obtained therefrom to determine the average particle size (ordinarily, 300 or more particles are measured to determine the average particle size).

The refractive index of the colorless transparent particle is preferably from 1.6 to 2.8, more preferably from 1.7 to 2.7, and most preferably from 1.8 to 2.7.

The primary particle size of the colorless transparent particle is preferably from 1 to 100 nm, and more preferably from 1 to 60 nm.

The colorless transparent particle may be either crystalline or amorphous and may be a monodisperse particle or may be even an aggregate particle so far as the predetermined particle size is satisfied. The shape thereof is most preferably a spherical shape but may also be a beaded shape, a shape having a major axis/minor axis ratio of 1 or more or an indefinite shape. The specific surface area of the colorless transparent particle is preferably from 10 to 2,000 m²/g, more preferably from 20 to 1,800 m²/g, and most preferably from 40 to 1,500 m²/g.

As the colorless transparent particle, a commercially available product may be preferably used.

Examples of the commercially available product which can be used include TTO Series (for example, TTO-51(A) or TTO-51(C)), TTO-S and V Series (for example, TTO-S-1, TTO-S-2 or TTO-V-3) produced by Ishihara Sangyo Kaisha, Ltd., and MT Series (for example, MT-01 or MT-05) produced by Tayca Corp.

In the case of adding the colorless transparent particle to the transparent polymerizable composition in the form of a dispersion containing the colorless transparent particle and a dispersing agent (the dispersing agent will be described in detail below), the content of the colorless transparent particle in the colorless transparent particle dispersion is preferably from 10 to 50% by weight, more preferably from 15 to 40% by weight, and still more preferably from 15 to 30% by weight.

The content of the colorless transparent particle in the transparent polymerizable composition is preferably from 10 to 95 % by weight, more preferably from 20 to 90% by weight, and still more preferably from 30 to 80% by weight, based on the total solid content of the transparent polymerizable composition.

-Dispersing agent~

In the case where the transparent polymerizable composition particularly contains the colorless transparent particle, the transparent polymerizable composition may contain a dispersing agent in order to increase the dispersibility of the colorless transparent particle. The dispersing agent can be appropriately selected to use from known dispersing agents and examples thereof include a cationic surfactant, a fluorine-based surfactant and a polymer dispersing agent.

Various kinds of compounds are used as the dispersing agent, and examples of the dispersing agent include a phthalocyanine derivative (EFKA-745 produced by EFKA or SOLSPERSE 5000 produce by Lubrizol Japan Ltd.); Organosiloxane Polymer KP341 produced by Shin-Etsu Chemical Co., Ltd., a (meth)acrylic (co)polymer (POLYFLOW No. 75, No. 90 and No. 95 (produced by yoeisha Chemical Co., Ltd.), a cationic surfactant, for example, W001 (produced by produced by Yusho Co., Ltd.); a nonionic surfactant, for example, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, sorbitan fatty acid ester or PIONIN D-6315 and D-6112W (produced by Takemoto Oil & Fat Co., Ltd.); an anionic surfactant, for example, W004, W005 or W017 (produced by Yusho Co., Ltd.); a fluorine-based surfactant, for example, MEGAFAC F781 (produced by DIC Corp.); a polymer dispersing agent, for example, BYK-2001 (produced by BYK-Chemie), EFKA-46, EFKA-47, EFKA-47EA, EFKA Polymer 100, EFKA Polymer 400, EFKA Polymer 401 and EFKA Polymer 450 (produced by Morishita & Co., Ltd.), DISPERSE AID 6, DISPERSE AID 8, DISPERSE AID 15 and DISPERSE AID 9100 (produced by San Nopco Ltd.); various SOLSPERSE dispersing agent, for example, SOLSPERSE 3000, 5000, 9000, 12000, 13240, 13940, 17000, 20000, 24000, 26000 and 28000 (produce by Lubrizol Japan Ltd.); ADEKA PLURONIC L31, F38, L42, L44, L61, L64, F68, L72, P95, F77, P84, F87, P94, L101, P103, F108, L121 and P-123 (produced by ADEKA Corp.); and IONET S-20 (produced by Sanyo Chemical Industries, Co., Ltd.)

The dispersing agents may be used individually or in combination of two or more thereof. The amount of the dispersing agent added to the transparent polymerizable composition according to the invention is preferably approximately from 0.1 to 50 parts by weight to 100 parts by weight of the pigment.

-Radical polymerization initiator-

The transparent polymerizable composition according to the invention preferably further contains a radical polymerization initiator from the standpoint of further increase in the sensitivity.

The radical polymerization initiator is preferably a radical photopolymerization initiator. It is preferred to add the radical photopolymerization initiator because the radical photopolymerization initiator imparts photosensitivity to the polymerizable composition to provide a photosensitive composition, whereby the composition can be suitably used, for example, as a resist for forming a transparent pixel (white pixel) of color filter. As the radical polymerization initiator, compounds known as photopolymerization initiators described below can be employed.

The photopolymerization initiator is not particularly restricted so far as it has an ability of initiating polymerization of the polymerizable compound described above and can be appropriately selected from known photopolymerization initiators. For example, those having photosensitivity to light in a region from ultraviolet to visible light are preferred. The photopolymerization initiator may also be an activator capable of causing a certain action with a photoexcited sensitizer to generate an active radical or an initiator capable of initiating cationic polymerization depending on the kind of the monomer.

Further, the photopolymerization initiator preferably contains at least one kind of a component having a molecular extinction coefficient of at least about 50 in the range from about 300 to about 800 nm (more preferably from 330 to 500 nm).

Examples of the photopolymerization initiator include a halogenated hydrocarbon derivative (for example, a compound having a triazine skeleton or a compound having an oxadiazole skeleton), an acylphosphine compound, for example, an acylphosphine oxide, a hexaarylbiimidazole, an oxime compound, for example, an oxime derivative, an organic peroxide, a thio compound, a ketone compound, an aromatic onium salt, a ketoxime ether, an aminoacetophenone compound and a hydroxyacetophenone.

Examples of the halogenated hydrocarbon compound having a triazine skeleton include compounds described in Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), compounds described in Britain Patent 1,388,492, compounds described in JP-A-53-133428, compounds described in Germany Patent 3337024, compounds described in F.C. Schaefer et al., J. Org. Chem., 29, 1527 (1964), compounds described in JP-A-62-58241, compounds described in JP-A-5-281728, compounds described in JP-A-5-34920 and compounds described in U.S. Patent 4,212,976.

The compounds described in U.S. Patent 4,212,976 include, for example, a compound having an oxadiazole skeleton (for example, 2-trichloromethyl-5-phenyl-l,3,4-oxadiazole,

2-trichloromethyl-5-(4-chlorophenyl)-l,3,4-oxadiazole,

2-trichloromethyl-5-( 1 -naphthyl)- 1 ,3 ,4-oxadiazole,

2-trichloromethyl-5-(2-naphthyl)-l,3,4-oxadiazole, 2-tribromomethyl-5-phenyl-l,3,4-oxadiazole, 2-tribromomethyl-5-(2-naphthyl)-l,3,4-oxadiazole, 2-trichloromethyl-5-styryl-l,3,4-oxadiazole, 2-trichloromethyl-5-(4-chlorostyryl)- 1 ,3,4-oxadiazole,

2-trichloromethyl-5-(4-methoxystyryl)-l,3,4-oxadiazole,

2-trichloromethyl-5-(l -naphthyl)- 1 ,3,4-oxadiazole,

2-trichloromethyl-5-(4-n-buthoxystyryl)-l ,3,4-oxadiazole or

2- tribromomethyl-5-styryl- 1 ,3 ,4-oxadiazole).

Examples of the photopolymerization initiator other than those described above include an acridine derivative (for example, 9-phenylacridine or l,7-bis(9,9'-acridinyl)heptane),

N-phenylglycine, a polyhalogen compound (for example, carbon tetrabromide, phenyl

tribromomethyl sulfone or phenyl trichloromethyl ketone), a coumarin (for example,

3 -(2-benzofuroyl)-7-diethylaminocoumarin, 3 -(2-benzofuroyl)-7-( 1 -pyrrolidinyl)coumarin,

3- benzoyl-7-diethylaminocoumarin, 3-(2-methoxybenzoyl)-7-diethylaminocoumarin,

3-(4-dimemylaminobenzoyl)-7-diethylaminocoumarin, 3,3'-carbonylbis(5,7-di-n-propoxycoumarin), 3,3' -carbonylbis(7-diethylaminocoumarin), 3 -benzoyl- 7-methoxycoumarin,

3-(2-furoyl)-7-diethylaminocoumarin, 3-(4-diemylammocinnamoyl)-7-diemylaminocoumarin, 7-methoxy-3-(3-pyridylcarbonyl)coumarin, 3-benzoyl-5,7-dipropoxycoumarin,

7-benzotriazol-2-ylcoumarin or coumarin compounds described, for example, in JP-A-5- 19475, JP-A-7-271028, JP-A-2002-363206, JP-A-2002-363207, JP-A-2002-363208 and

JP-A-2002-363209), an acylphosphine oxide (for example,

bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimemoxybenzoyl)-2,4,4-trimethylpentylphenylphosphine oxide or Lucirin TPO), a metallocene (for example,

bis(r|5 -2,4-cyclopentadien- 1 -yl)-bis(2,6-difluoro-3 -( 1 H-pyrrol- 1 -yl)phenyl)titanium or

η5-cyclopentadienyl-η6-cumenyl-iron(l+)-hexafluorophosphate(l-)), and compounds described, for example, in JP-A-53- 133428, JP-B-57-1819, JP-B-57-6096 and U.S. Patent 3,615,455.

Examples of the ketone compound include benzophenone, 2-methylbenzophenone,

3- methylbenzophenone, 4-methylbenzophenone, 4-methoxybenzophenone, 2-chlorobenzophenone,

4- chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone,

2-ethoxycarbonylbenzophenone, benzophenone tetracarboxylic acid or a tetramethyl ester thereof, a 4,4'-bis(dialkylamino)benzophenone (for example, 4,4'-bis(dimethylamino)benzophenone, 4,4' -bis(dicyclohexylamino)benzophenone, 4,4' -bis(diethylamino)benzophenone or

4,4'-bis(dihydroxyethylamino)benzophenone), 4-methoxy-4'-dimemylaminobenzophenone, 4,4' -dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, benzyl, anthraquinone, 2-tert-butylanthraquinone, 2-methylanthraquinone, phenanthraquinone, xanthone, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, fluorenone,

2-benzyl-2-dimethylamino- 1 -(4-moφholinophenyl)- 1 -butanone,

2-memyl-l-[4-(memylthio)phenyl]-2-moφholi o-l- ropanone,

2-hydroxy-2-methyl-[4-(l-methylvinyl)phenyl]propanol oligomer, benzoin, a benzoin ether (for example, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin phenyl ether or benzyl dimethyl ketal), acridone, chloroacridone, N-methylacridone, N-butylacridone and N-butyl-chloroacridone.

A hydroxyacetophenone compound, an aminoacetophenone compound and an acylphosphine compound may also be suitably used as the photopolymerization initiator. More specifically, for example, an aminoacetophenone initiator described in JP-A- 10-291969 and an acylphosphine oxide initiator described in Japanese Patent No. 4,225,898 may be used.

As the hydroxyacetophenone initiator, IRGACURE-184, DAROCUR-1173, IRGACURE-500, IRGACURE-2959 and IRGACURE-127 (trade names, all produced by BASF) may be used. As the aminoacetophenone initiator, commercially available IRGACURE-907, IRGACURE-369 and IRGACURE-379 (trade names, all produced by BASF) may be used. As the aminoacetophenone initiator, compounds in which the absoφtion wavelength matches a light source having a long wavelength, for example, 365 nm or 405 nm described in JP-A-2009-191179 may also be used. As the acylphosphine initiator, commercially available IRGACURE-819 and DAROCUR-TPO (trade names, both produced by BASF) may be used.

The photopolymerization initiator more preferably includes an oxime compound. Specific examples of the oxime initiator used include compounds described in JP-A-2001 -233842, compounds describe in JP-A-2000-80068 and compounds described in JP-A-2006-342166.

Examples of the oxime compound, for example, an oxime derivative, which is suitably used as the photopolymerization initiator in the invention, include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutan-2-one, 3-propionyloxyiminobutan-2-one, 2-acetoxyiminopentan-3-one, 2-acetoxyimino- 1 -phenylpropan- 1 -one, 2-benzoyloxyimino- 1 -phenylpropan- 1 -one, 3-(4-toluenesulfonyloxy)iminobutan-2-one and 2-ethoxycarbonyloxyimino- 1 -phenylpropan- 1 -one.

Examples of the oxime ester compound include the compounds described in J. C. S. Perkin II, pp. 1653-1660 (1979), J. C. S. Perkin II, pp. 156-162 (1979), Journal of Photopolvmer Science and Technology, pp. 202-232 (1995), JP-A-2000-66385, JP-A-2000-80068, JP-T-2004-534797 (the term "JP-T" as used herein means a published Japanese translation of a PCT patent application) and JP-A-2006-342166.

Commercially available IRGACURE-OXE01 (produced by BASF) and IRGACURE-OXE02 (produced by BASF) may be also suitably used.

As the oxime ester compound other than those described above, for example, compounds described in JP-T-2009-519904 where oxime is connected to N-position of carbazole, compounds described in U.S. Patent 7,626,957 where a hetero substituent is introduced into a benzophenone moiety, compounds described in JP-A-2010-15025 and U.S. Patent Application Publication No. 2009-292039 where a nitro group is introduced into a dye moiety, ketoxime compounds described in WO 2009/131189, compounds containing a triazine skeleton and an oxime skeleton in the same molecule described in U.S. Patent 7,556,910 and compounds having an absorption maximum at 405 nm and exhibiting good sensitivity to a g-ray light source described in JP-A-2009-221114 may be also used.

Furthermore, cyclic oxime compounds described in JP-A-2007-231000 and JP-A-2007-322744 may be also suitably used. Of the cyclic oxime compounds, cyclic oxime compounds fused to a carbazole dye described in JP-A-2010-32985 and JP-A-2010-185072 are preferred from the standpoint of high light absorbing property and high sensitivity. Also, oxime compounds having an unsaturated bond at a specific site thereof described in JP-A-2009-242469 can be suitably used because they can achieve high sensitivity by regenerating an active radical from a polymerization inactive radical.

Most preferably, oxime compounds having a specific substituent described in JP-A-2007-269779 and oxime compounds having a thioaryl group described in JP-A-2009-191061 are exemplified.

Specifically, the oxime photopolymerization initiator is preferably a compound represented by formula (1) shown below. The oxime compound may be a compound where the N-0 bond of oxime is (E) form, a compound where the bond is (Z) form or a compound where the bond is a mixture of (E) form and (Z) form.

In formula (1), R and B each independently represents a monovalent substituent, A represents a divalent organic group, and Ar represents an aryl group.

In formula (1), the monovalent substituent represented by R is preferably a monovalent nonmetallic atom group. Examples of the monovalent nonmetallic atom group include an alkyl group, an aryl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a heterocyclic group, an alkylthiocarbonyl group and an arylthiocarbonyl group. These groups may have one or more substituents. The substituent described above may be further substituted with other substituent.

Examples of the substituent include a halogen atom, an aryloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acyl group, an alkyl group and an aryl group.

The alkyl group which may have a substituent is preferably an alkyl group having from 1 to 30 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a decyl group, a dodecyl group, an octadecyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a 1-ethylpentyl group, a cyclopentyl group, a cyclohexyl group, a trifluoromethyl group, a 2-ethylhexyl group, a phenacyl group, a 1-naphthoylmethyl group, a 2-naphthoylmethyl group, a

4- methylsulfanylphenacyl group, a 4-phenylsulfanylphenacyl group, a 4-dimethylaminophenacyl group, a 4-cyanophenacyl group, a 4-methylphenacyl group, a 2-methylphenacyl group, a 3-fluorophenacyl group, a 3-trifluoromethylphenacyl group and a 3-nitrophenacyl group.

The aryl group which may have a substituent is preferably an aryl group having from 6 to 30 carbon atoms, and specific examples thereof include a phenyl group, a biphenyl group, a 1-naphthyl group, a 2-naphthyl group, a 9-anthryl group, a 9-phenanthryl group, a 1-pyrenyl group, a

5- naphthacenyl group, a 1-indenyl group, a 2-azulenyl group, a 9-fluorenyl group, a terphenyl group, a quaterphenyl group, an o-, m- or p-tolyl group, a xylyl group, an o-, m- or p-cumenyl group, a mesityl group, a pentalenyl group, a binaphthalenyl group, a ternaphthalenyl group, a quaternaphthalenyl group, a heptalenyl group, a biphenylenyl group, an indacenyl group, a fluoranthenyl group, an acenaphthylenyl group, an aceanthrylenyl group, a phenalenyl group, a fluorenyl group, an anthryl group, a bianthracenyl group, a teranthracenyl group, a quateranthracenyl group, an anthraquinolyl group, a phenanthryl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a pleiadenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a pentacenyl group, a tetraphenylenyl group, a hexaphenyl group, a hexacenyl group, a rubicenyl group, a coronenyl group, a trinaphthylenyl group, a heptaphenyl group, a heptacenyl group, a pyranthrenyl group and an ovalenyl group.

The acyl group which may have a substituent is preferably an acyl group having from 2 to 20 carbon atoms, and specific examples thereof include an acetyl group, a propanoyl group, a butanoyl group, a tnfluoroacetyl group, a pentanoyl group, a benzoyl group, a 1-naphthoyl group, a 2-naphthoyl group, a 4-methylsulfanylbenzoyl group, a 4-phenylsulfanylbenzoyl group, a 4-dimethylaminobenzoyl group, a 4-diethylaminobenzoyl group, a 2-chlorobenzoyl group, a 2-methylbenzoyl group, a 2-methoxybenzoyl group, a 2-butoxybenzoyl group, a 3-chlorobenzoyl group, a 3-trifluoromethylbenzoyl group, a 3-cyanobenzoyl group, a 3-nitrobenzoyl group, a 4-fluorobenzoyl group, a 4-cyanobenzoyl group and a 4-methoxybenzoyl group.

The alkoxycarbonyl group which may have a substituent is preferably an alkoxycarbonyl group having from 2 to 20 carbon atoms, and specific examples thereof include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, a hexyloxycarbonyl group, an octyloxycarbonyl group, a decyloxycarbonyl group, an octadecyloxycarbonyl group and a trifluoromethyloxycarbonyl group.

Specific examples of the aryloxycarbonyl group which may have a substituent include a phenoxycarbonyl group, a 1-naphthyloxycarbonyl group, a 2-naphthyloxycarbonyl group, a

4-methylsulfanylphenyloxycarbonyl group, a 4-phenylsulfanylphenyloxycarbonyl group, a

4-dimethylaminophenyloxycarbonyl group, a 4-diethylaminophenyloxycarbonyl group, a

2-chlorophenyloxycarbonyl group, a 2-methylphenyloxycarbonyl group, a

2- methoxyphenyloxycarbonyl group, a 2-butoxyphenyloxycarbonyl group, a

3- chlorophenyloxycarbonyl group, a 3-trifluoromethylphenyloxycarbonyl group, a

3-cyanophenyloxycarbonyl group, a 3-nitrophenyloxycarbonyl group, a 4-fluorophenyloxycarbonyl group, a 4-cyanophenyloxycarbonyl group and a 4-methoxyphenyloxycarbonyl group.

The heterocyclic group which may have a substituent is preferably an aromatic or aliphatic heterocyclic group containing a nitrogen atom, an oxygen atom, a sulfur atom or a phosphorus atom. Specific examples thereof include a thienyl group, a benzo[b]thienyl group, a naphtho[2,3-b]thienyl group, a thianthrenyl group, a furyl group, a pyranyl group, an isobenzofuranyl group, a chromenyl group, a xanthenyl group, a phenoxathiinyl group, a 2H-pyrrolyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an indolizinyl group, an isoindolyl group, a 3H-indolyl group, an indolyl group, a IH-indazolyl group, a purinyl group, a 4H-quinolizinyl group, an isoquinolyl group, a quinolyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxanilyl group, a quinazolinyl group, a cinnolinyl group, a pteridinyl group, a 4aH-carbazolyl group, a carbazolyl group, a β-carbolinyl group, a phenanthridinyl group, an acridinyl group, a perimidinyl group, a phenanthrolinyl group, a phenazinyl group, a phenarsazinyl group, an isothiazolyl group, a phenothiazinyl group, an isoxazolyl group, a furazanyl group, a phenoxazinyl group, an isochromanyl group, a chromanyl group, a pyrrolidinyl group, a pyrrolinyl group, an imidazolidinyl group, an imidazolinyl group, a pyrazolidinyl group, a pyrazolinyl group, a piperidyl group, a piperazinyl group, an indolinyl group, an isoindolinyl group, a quinuclidinyl group, a morpholinyl group and a thioxantholyl group.

Specific examples of the alkylthiocarbonyl group which may have a substituent include a methylthiocarbonyl group, a propylthiocarbonyl group, a butylthiocarbonyl group, a hexylthiocarbonyl group, an octylthiocarbonyl group, a decylthiocarbonyl group, an octadecylthiocarbonyl group and a trifluoromethylthiocarbonyl group.

Specific examples of the arylthiocarbonyl group which may have a substituent include a

1- naphthylthiocarbonyl group, a 2-naphthylthiocarbonyl group, a

4-methylsulfanylphenylthiocarbonyl group, a 4-phenylsulfanylphenylthiocarbonyl group, a

4-dimethylaminophenylthiocarbonyl group, a 4-diethylaminophenylthiocarbonyl group, a

2- chlorophenylthiocarbonyl group, a 2-methylphenylthiocarbonyl group, a

2- methoxyphenylthiocarbonyl group, a 2-butoxyphenylthiocarbonyl group, a

3- chlorophenylthiocarbonyl group, a 3-trifluoromethylphenylthiocarbonyl group, a

3-cyanophenylthiocarbonyl group, a 3-nitrophenylthiocarbonyl group, a 4-fluorophenylthiocarbonyl group, a 4-cyanophenylthiocarbonyl group and a 4-methoxyphenylthiocarbonyl group.

The monovalent substituent represented by B represents an aryl group, a heterocyclic group, an arylcarbonyl group or a heterocyclic carbonyl group. These groups may have one or more substituents. Examples of the substituent include the substituents described above. Also, the substituent described above may be further substituted with other substituent.

Among them, structures shown below are particularly preferred.

In the structures below, Y, X and n have the same meanings as Y, X and n in Formula (2) described below, and preferred examples thereof are also the same.

Examples of the divalent organic group represented by A include an alkylene group having from 1 to 12 carbon atoms, a cyclohexylene and an alkynylene group. These groups may have one or more substituents. Examples of the substituent include the substituents described above. Also, the substituent described above may be further substituted with other substituent.

Among them, from the standpoint of increasing sensitivity and inhibiting coloration due to heating aging, A is preferably an unsubstituted alkylene group, an alkylene group substituted with an alkyl group (for example, a methyl group, an ethyl group, a tert-butyl group or a dodecyl group), an alkylene group substituted with an alkenyl group (for example, a vinyl group or an allyl group) or an alkylene group substituted with an aryl group (for example, a phenyl group, a p-tolyl group, a xylyl group, a cumenyl group, a naphthyl group, an anthryl group, a phenanthryl group or a styryl group).

The aryl group represented by Ar is preferably an aryl group having from 6 to 30 carbon atoms and may have a substituent. Examples of the substituent are the same as those of the substituent introduced into the substituted aryl group described above as the specific example of the aryl group which may have a substituent.

Among them, from the standpoint of increasing sensitivity and inhibiting coloration due to heating aging, a substituted or unsubstituted phenyl group is preferred.

In formula (1), the structure "SAr" formed by Ar and S adjacent thereto is preferably a structure shown below from the standpoint of sensitivity. In the structures below, Me represents a methyl group, and Et represents an ethyl group.

The oxime com ound is preferably a compound represented by formula (2) shown below.

In formula (2), R and X each independently represents a monovalent substituent, A and Y each independently represent a divalent organic group, Ar represents an aryl group, and n represents an integer from 0 to 5.

In formula (2), R, A and Ar have the same meanings as R, A and Ar in formula (1), and preferred examples thereof are also the same.

Examples of the monovalent substituent represented by X include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkoxycarbonyl group, an amino group, a heterocyclic group and a halogen atom. These groups may have one or more substituents. Examples of the substituent include the substituents described above. Also, the substituent described above may be further substituted with other substituent.

Among them, X is preferably an alkyl group from the standpoint of solvent solubility and increase in absorption efficiency in the long wavelength region.

In formula (2), n represents an integer from 0 to 5, and is preferably an integer from 0 to 2.

Examples of the divalent organic group represented by Y include structures shown below. In the groups shown below, * indicates a connecting position to the carbon atom adjacent to Y in formula (2).

Among them, structures shown below are preferred from the standpoint of high sensitivity.

Further, the oxime compound is preferably a compound represented by formula (3) shown below.

In formula (3), R and X each independently represents a monovalent substituent, A represents a divalent organic group, Ar represents an aryl group, and n is an integer from 0 to 5.

In formula (3), R, X, A, Ar and n have the same meanings as R, X, A, Ar and n in formula (2), and preferred examples thereof are also the same.

Specific examples (C-4) to (C-13) of the oxime compound suitably used are set forth below, but the invention should not be construed as being limited thereto.

The oxime compound is a compound having a maximum absorption wavelength in the wavelength region from 350 to 500 nm, preferably a compound having a maximum absorption wavelength in the wavelength region from 360 to 480 nm, and particularly preferably a compound having high absorbance at wavelengths of 365 nm and 405 nm.

The molar extinction coefficient at a wavelength of 365 nm or 405 nm of the oxime compound is preferably from 1,000 to 300,000, more preferably from 2,000 to 300,000, particularly preferably from 5,000 to 200,000, from the standpoint of sensitivity.

The molar extinction coefficient of compound can be determined using a known method and specifically, for example, it is preferably measured at a concentration of 0.01 g/L using an ethyl acetate solvent by an ultraviolet-visible spectrophotometer (Carry-5 Spectrophotometer, produced by Van an, Inc.).

The radical photopolymerization initiators which can be used in the invention may be employed in combination of two or more thereof, if desired.

The content (total content in case of using two or more kinds) of the radical photopolymerization initiator in the transparent polymerizable composition is preferably in a range from 0.1 to 20% by weight, more preferably in a range from 0.5 to 10% by weight, particularly preferably in a range from 1 to 8% by weight, based on the total solid content of the transparent polymerizable composition. In the range described above, good sensitivity and good pattern-forming property can be achieved.

The transparent polymerizable composition may contain a sensitizer for the purpose of improving radical generation efficiency of a radical initiator and shifting the sensitive wavelength to a longer wavelength. The sensitizer which can be used in the invention is preferably a sensitizer capable of sensitizing the radical photopolymerization initiator described above by the electron transfer mechanism or energy transfer mechanism.

Examples of the sensitizer which can be used in the transparent polymerizable composition include compounds described in Paragraph Nos. [0101] to [0154] of JP-A-2008-32803.

The content of the sensitizer in the transparent polymerizable composition is preferably from 0.1 to 20% by weight, more preferably from 0.5 to 15% by weight, in terms of solid content from the standpoint of light absorption efficiency to the deep portion and decomposition efficiency of the initiator.

The sensitizers may be used individually or in combination of two or more thereof.

-Organic solvent-

The transparent polymerizable composition according to the invention ordinarily contains an organic solvent. The organic solvent is basically not particularly restricted so far as the solubility of each component and the coating property of the transparent polymerizable composition are satisfied. The organic solvent is preferably selected in particular consideration of solubility of binder, coating property and safety. Also, in the preparation of transparent polymerizable composition according to the invention, it is preferred to use at least two kinds of the organic solvents.

Preferred examples of the organic solvent include an ester, for example, ethyl acetate, n-butyl acetate, isobutyl acetate, amyl formate, isoamyl acetate, isobutyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, methyl lactate, ethyl lactate, an alkyl oxyacetate (for example, methyl oxyacetate, ethyl oxyacetate, butyl oxyacetate (for example, methyl methoxyacetate, ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate or ethyl ethoxyacetate)), an alkyl 3-oxypropionate (for example, methyl 3-oxypropionate or ethyl 3-oxypropionate (for example, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate or ethyl 3-ethoxypropionate)), an alkyl 2-oxypropionate (for example, methyl 2-oxypropionate, ethyl 2-oxypropionate, propyl 2-oxypropionate (for example, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, methyl 2-ethoxypropionate or ethyl 2-ethoxypropionate)), methyl 2-oxy-2-methylpropionate, ethyl 2-oxy-2-methylpropionate (for example, methyl 2-methoxy-2-methylpropionate or ethyl

2- ethoxy-2-methylpropionate), methyl pyruvate, ethyl pyruvate, propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl 2-oxobutanoate or ethyl 2-oxobutanoate; an ether, for example, diethylene glycol dimethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate or propylene glycol monopropyl ether acetate; a ketone, for example, methyl ethyl ketone, cyclohexanone, 2-heptanone or 3-heptanone; and an aromatic hydrocarbon, for example, toluene or xylene.

From the standpoint of solubility of the monomer or resin, improvement in the coated surface state or the like, it is also preferred to mix two or more of the organic solvents. In this case, a mixed solution composed of two or more solvents selected from methyl 3-ethoxypropionate, ethyl

3- ethoxypropionate, ethyl cellosolve acetate, ethyl lactate, diethylene glycol dimethyl ether, butyl acetate, methyl 3-methoxypropionate, 2-heptanone, cyclohexanone, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol methyl ether and propylene glycol methyl ether acetate is particularly preferred.

From the standpoint of coating property, the content of the organic solvent in the transparent polymerizable composition is an amount to make the total solid content concentration of the transparent polymerizable composition preferably from 5 to 80% by weight, more preferably from 5 to 60% by weight, and particularly preferably from 10 to 50% by weight.

-Other additives-

The transparent polymerizable composition according to the invention may further contain various additives, if desired. Specific examples of the various additives include various additives described in JP-A-2005-326453. For example, a silane coupling agent is exemplified, and KBM-602 (produced by Shin-Etsu Chemical Co., Ltd.) is suitably used.

More specifically, the transparent polymerizable composition is preferably a composition which forms a cured film having a thickness of 1 um wherein light transmittance in a thickness direction of the cured film over a wavelength range from 400 to 700 nm is 90% or more.

Such a physical property of the light transmittance (transparency) is suitably achieved by adjusting the kind and content of each component contained in the transparent polymerizable composition. Also, in the case where the transparent polymerizable composition contains the colorless transparent particle described above, the physical property of the light transmittance is suitably achieved, for example, by adjusting the particle size of the colorless transparent particle or by adding a dispersing agent and adjusting its kind and amount.

With respect to the transparent polymerizable composition, the light transmittance over a wavelength range from 400 to 700 nm of 90% or more as described above is suitable for the transparent cured film or transparent cured pattern to sufficiently function as a base layer of a color filter or a transparent pixel (white pixel) in a color filter.

The light transmittance over the wavelength range from 400 to 700 nm described above is preferably 95% or more, more preferably 99% or more, and most preferably 100%.

The transparent polymerizable composition according to the invention is substantially not contain a coloring agent (content of the coloring agent is preferably 0% by weight based on the total solid content of the composition).

[Colored radiation-sensitive composition]

Now, the colored radiation-sensitive composition is described in detail below.

The colored radiation-sensitive composition (more specifically, each of the first colored radiation-sensitive composition, second colored radiation-sensitive composition and third colored radiation-sensitive composition in the embodiment described above) ordinarily contains a coloring agent.

The colored radiation-sensitive composition is preferably an embodiment containing at least any one of a colored pigment or a dye, as the coloring agent.

The first colored radiation-sensitive layer 11 is preferably a green color transmitting layer or a black colored layer for black matrix, and more preferably a green color transmitting layer.

The coloring agent used in the first colored radiation-sensitive layer is preferably one or more coloring agents selected from C. I. Pigment Green 7, 10, 36, 37 and 58, and C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125, 126, 127, 128, 129, 137, 138, 139, 147, 148, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 193, 194, 199, 213 and 214.

It is preferred the one of the second colored pixel and third colored pixel is a red color transmitting portion and the other is a blue color transmitting portion.

The coloring agent used in the colored composition for forming the red color transmitting portion is preferably one or more coloring agents selected from C. I. Pigment Orange 2, 5, 13, 16, 17:1, 31, 34, 36, 38, 43, 46, 48, 49, 51, 52, 55, 59, 60, 61, 62, 64, 71 and 73, and C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 9, 10, 14, 17, 22, 23, 31, 38, 41, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 49:2, 52:1, 52:2, 53:1, 57:1, 60:1, 63:1, 66, 67, 81 :1, 81:2, 81:3, 83, 88, 90, 105, 112, 119, 122, 123, 144, 146, 149, 150, 155, 166, 168, 169, 170, 171, 172, 175, 176, 177, 178, 179, 184, 185, 187, 188, 190, 200, 202, 206, 207, 208, 209, 210, 216, 220, 224, 226, 242, 246, 254, 255, 264, 270, 272 and 279. The coloring agent contained in the colored composition for forming the blue color transmitting portion is preferably one or more coloring agents selected from C. I. Pigment Violet 1, 19, 23, 27, 32, 37 and 42, and C. I. Pigment Blue 1, 2, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 22, 60, 64, 66, 79 and 80.

In each of the first colored radiation-sensitive composition, second colored radiation-sensitive composition and the third colored radiation-sensitive composition, the content of the coloring agent to the total solid content of the composition is preferably 30% by weight or more, more preferably 35% by weight or more, and still more preferably 40% by weight or more. Also, the content of the coloring agent to the total solid content of the composition is ordinarily 90% by weight or less, and preferably 80% by weight or less.

Also, as each of the first colored radiation-sensitive composition, second colored radiation-sensitive composition and the third colored radiation-sensitive composition, a negative radiation-sensitive composition is preferably used. As the negative radiation-sensitive composition, a negative radiation-sensitive composition which responds to radiation, for example, an ultraviolet ray (g-ray, h-ray or i-ray), a far ultraviolet ray including an excimer laser or the like, an electron beam, an ion beam or an X-ray is used. Of the radiations, g-ray, h-ray or i-ray is preferred and i-ray is more preferred.

Specifically, the negative radiation-sensitive composition is preferably a composition containing, for example, a photopolymerization initiator, a polymerization component (polymerizable compound) and a binder resin (for example, an alkali-soluble resin) is preferred and includes, for example, compositions described in Paragraph Nos. [0017] to [0064] of JP-A-2005-326453.

It is utilized that in such a negative radiation-sensitive composition, upon the irradiation of radiation the photopolymerization initiator initiates a polymerization reaction of the polymerizable compound and as a result, the composition is changed from an alkali-soluble state to an alkali-insoluble state.

The exposure of the first colored radiation-sensitive layer 11, second colored radiation-sensitive layer 21 and third colored radiation-sensitive layer 31 can be performed by exposing each layer to g-ray, h-ray or i-ray, preferably to i-ray.

The development carried out after the exposure is ordinarily performed by development processing with a developer.

As the developer, for example, a combination of various organic solvents or an aqueous alkaline solution is used. As the aqueous alkaline solution, an aqueous alkaline solution prepared by dissolving an alkaline compound so as to have concentration from 0.001 to 10% by weight, preferably from 0.01 to 5% by weight, is suitable. Examples of the alkaline compound include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, diethylamine, dimethylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine and l,8-diazabicyclo-[5.4.0]-7-undecene. When an aqueous alkaline solution is used as the developer, a washing treatment with water is ordinarily conducted after the development.

A length of one side of the first colored pixel, second colored pixel or third colored pixel (indicating a length of a short side when the pixel is a rectangle and a length of one side when the pixel is a square) is preferably from 0.5 to 1.7 um, more preferably from 0.6 to 1.5 μπι, from the standpoint of image resolution.

In the case where the colored coating layer or colored pattern formed by the colored radiation-sensitive composition is subjected to the heating step in the environment where oxygen concentration of 100 ppm or less, the colored radiation-sensitive composition contains a compound having a heat-polymerizable group. Specific examples of the compound having a heat-polymerizable group, preferred examples thereof and preferred range of the content thereof based on the total solid content of the colored radiation-sensitive composition are same as those described with respect to the transparent polymerizable composition above. The compound having a heat-polymerizable group may be a compound corresponding to a photopolymerizable compound so far as it has a heat-polymerization property or a compound having a heat-polymerization property among the compounds described in Paragraph Nos. [0017] to [0064] of JP-A-2005-326453 above.

The colored radiation-sensitive composition may contain each of the components described in the transparent polymerizable composition above so far as it contains the coloring agent described above, and in this case the content of each component (on a weight basis of the total solid content of the composition) is same as that described with respect to the transparent polymerizable composition above.

The color filter obtained by the method for producing a color filter according to the invention can be suitably used for a liquid crystal display device (LCD) or a solid-state imaging device (for example, CCD or CMOS). Also, it can be suitably used for an image display device, for example, electronic paper or an organic EL display device. In particular, the color filter according to the invention can be suitably used for a solid-state imaging device, for example, CCD or CMOS.

Further, the color filter according to the invention is suitable as a color filter for a liquid crystal display device. In this case, the cured film or cured pattern obtained by the method for forming a cured film or cured pattern according to the invention is suitably applied to a transparent member capable of forming by the transparent polymerizable composition containing compound having a heat-polymerizable group, a base layer for color filter, a colored pixel in a color filter or the like, each of which is an existing member constituting the liquid crystal display device.

The liquid crystal display device can display images of high image quality having good tint and excellent display characteristics.

The definition of the display device and details of the respective display devices are described, for example, in Akio Sasaki, Denshi Display Device (Electronic Display Device), published by Kogyo Chosakai Publishing Co., Ltd. (1990) and Sumiaki Ibuki, Display Device (Display Device), published by Sangyo-Tosho Publishing Co., Ltd. (1989). The liquid crystal display devices are described, for example, in Tatsuo Uchida, ed., Jisedai Ekisho Display Gijustu (Next Generation Liquid Crystal Display Techniques), published by Kogyo Chosakai Publishing Co., Ltd. (1994). The liquid crystal display device to which the invention can be applied is not particularly restricted and the invention can be applied to liquid crystal display devices of various systems described, for example, in Jisedai Ekisho Display Gijustu (Next Generation Liquid Crystal Display Techniques) above.

The color filter according to the invention is useful for color TFT liquid crystal display devices. The color TFT Liquid crystal display device is described, for example, in Color TFT Ekisho Display (Color TFT Liquid Crystal Display), published by Kyoritsu Shuppan Co., Ltd. (1996). Further, the invention can also be applied to liquid crystal display devices with enlarged viewing angle, for instance, of a transverse electric field driving system, for example, IPS or of a pixel division system, for example, MVA, and STN, TN, VA, OCS, FFS and R-OCB.

Moreover, the color filter according to the invention is applicable to a COA (Color-filter On Array) system with brightness and high definition. In a colored layer formed in the COA system, it is necessary to form a conductive path, for example, a rectangular through-hole having a length of one side approximately from 1 to 15 um or a reversed C-shaped recess in order to bring an ITO electrode arranged on the colored layer and a terminal of a driving substrate below the colored layer into conduction. The dimension of the conductive path (that is, length of one side) is particularly preferably set to 5 μιη or less, and it is also possible to form a conductive path of 5 um or less by using the invention. These image display systems are described, for example, in EL, PDP, LCD Display - Gijutsu to Shijo no Saishin Doko - (EL, PDP, LCD Display - Current Trend of Techniques and Markets -), published by Investigative Research Department, Toray Research Center, Inc. (2001), page 43.

The liquid crystal display device according to the invention is composed of, as well as the color filter according to the invention, various members, for example, an electrode substrate, a polarizing film, a retardation film, a backlight, a spacer or a viewing angle compensation film. The color filter according to the invention is applied to liquid crystal display devices composed of these known members. These members are described, for example, in Kentaro Shima, '94 Ekisho Display Shuhen Zairyo Chemicals no Shijo ('94 Markets of Peripheral Materials and Chemicals for Liquid Crystal Displays! published by CMC Publishing Co., Ltd. (1994) and Ryokichi Omote, 2003 Ekisho Kanren Shijo no Genjyo to Shourai Tenbo (Gekan)(2003 Liquid Crystal Related Market and Future Outlook (Last Volume), published by Fuji Chimera Research Institute Inc. (2003).

The backlight is described, for example, in A. Konno et al., SID Meeting Digest 1380 (2005) and Gekkan Display (Monthly Display), December, 2005, pages 18 to 24 (Yasuhiro Shima) and pages 25 to 30 (Takaaki Yagi).

In case of using the color filter according to the invention in the liquid crystal display device, a high contrast is achieved when combined with a heretofore known three-wavelength cold-cathode tube. In addition, by using LED light sources of red, green and blue (RGB-LED) as the backlight, a liquid crystal display device having high brightness and good color reproducibility with high color purity can be provided.

Examples

The present invention will be more specifically described below with reference to the following examples, but the invention should not be construed as being limited thereto so far as the gist of the invention is not deviated. In case of conducting a treatment using a commercially available treating solution in each step, unless otherwise particularly indicated, the treatment is conducted according to the method specified by the maker. Examples 1

[Preparation of transparent polymerizable composition]

A transparent polymerizable composition was prepared by mixing the components shown below.

Compound having heat-polymerizable group: CYCLOMER ACA230p 12.191 parts by (CR- 1000) (Mw: 7,700, solid content acid value: 15 mgKOH/g) weight

(produced by Daicel Chemical Industries, Ltd.)

Fluorine-based surfactant: MEGAFAC F-781 (produced DIC Corp.) 0.834 parts by weight

Solvent: Propylene glycol monomethyl ether acetate (PGMEA) 54.56 parts by weight

Solvent: Ethyl 3-ethoxypropionate (EEP) 32.415 parts by weight

[Formation of transparent cured layer]

A coater developer (ACT8, produced by Tokyo Electron Ltd.) provided with a heating tank having a hot plate as a heating means and constituted so as to be able to introduce nitrogen gas into the heating tank and to seal was provided.

A silicon (Bare-Si) substrate was placed on the hot plate and the transparent polymerizable composition prepared as descried above was coated on the silicon (Bare-Si) substrate so as to have a thickness of 0.1 um. The coating was dried at 100°C for 2 minutes on the hot plate and cooled as it was at 23 °C for one minute on the hot plate to from a transparent coating layer.

Then, the heating tank was sealed and nitrogen gas was introduced into the heating tank while exhausting air from the heating tank. The oxygen concentration in the heating tank was 80 ppm.

The coating was heated at 200°C for 5 minutes on the hot plate and then cooled at 23°C to from a transparent cured layer.

[Preparation of green radiation-sensitive composition]

A green radiation-sensitive composition was prepared by mixing the components shown below. Pigment dispersion: Green pigment dispersion Gl shown below 51.2 parts

Photopolymerization initiator: IRGACURE OXE-01 (produced by 0.87 parts BASF)

Polymerizable compound: KAYARAD RP- 1040 (produced by Nippon 4.7 parts Kayaku Co., Ltd.)

Binder: ACA230AA (produced by Daicel Chemical Industries, Ltd.) 7.4 parts

Polymerization inhibitor: p-Methoxyphenol 0.002 parts

Additive: PIONIN D-6112-W (produced by Takemoto Oil & Fat Co., 0.19 parts Ltd.)

Silane coupling agent: 0.9% By weight cyclohexanone solution of 10.8 parts KBM-602 (produced by Shin-Etsu Chemical Co., Ltd.)

Solvent: PGMEA 14.3 parts

Solvent: Cyclohexanone 6.4 parts

Fluorine-based surfactant: 0.2% By weight cyclohexanone solution of 4.2 parts F-781 (produced by DIC Corp.)

(Preparation of Green pigment dispersion Gl)

A PGMEA solution containing green pigment (C. I. Pigment Green 36/C. I. Pigment Green 7/C. I. Pigment Yellow 139 = 80/20/30 in weight ratio) and BYK-161 (produced by BYK-Chemie) as a dispersing resin was mixed and dispersed in a bead mill for 15 hours to prepare Green pigment dispersion Gl having a solid content concentration of 25.5% by weight and a pigment concentration of 15.3% by weight.

[Formation of green color pattern]

The green radiation-sensitive composition prepared as descried above was coated on the transparent cured layer so as to have a thickness of 0.6 um. The coating was dried at 100°C for 3 minutes on the hot plate and cooled as it was at 23 °C for one minute on the hot plate to from a green radiation-sensitive layer. The green radiation-sensitive layer thus-obtained was subjected to pattern exposure using an i-ray stepper (FPA3000i5+, ΝΑ/σ = 0.60/0.65, produced by Canon Inc.) in an exposure amount of 350 mJ/cm . The exposure pattern was a checkered pattern wherein the length of one side of square grid was 1.2 urn.

Then, the stack after exposure was mounted on a horizontal rotary table of a spin shower developing machine (Model DW-30, produced by Chemitronics Co., Ltd.) and subjected to puddle development at 23 °C for 60 seconds using CD-2040 (produced by FUJIFILM Electronic Materials Co., Ltd.).

Thereafter, the stack was fixed on the horizontal rotary table with a vacuum chuck system, and subjected to a rinse treatment for 60 seconds by supplying ultrapure water (DIW) at 23 °C from a straight nozzle above the center of rotation while the stack was rotated by a rotator at a rotation speed of 50 rpm, followed by spray drying.

Thus, the stack in which the checkered green color pattern was formed on the transparent cured layer was obtained (corresponding to the state shown in Fig. 3).

The upper surface of the checkered green color pattern thus-obtained was observed using a critical dimension scanning electron microscope (S-9260, Mag: x 30.0k, HV/IP: 600v/8.0pA, produced by Hitachi High-Technologies Corp.) and as a result, the residue was hardly confirmed in the through-hole group of the green color pattern as shown in Fig. 8.

Comparative Example 1

A green color pattern was formed in the same manner as in Example 1 except that the post-baking treatment in the formation of transparent cured layer was performed in the atmosphere by using a hot plate not having a function of nitrogen gas substitution.

The upper surface of the checkered green color pattern thus-obtained was observed using a critical dimension scanning electron microscope (S-9260, Mag: x 30.0k, HV/IP: 600v/8.0pA, produced by Hitachi High-Technologies Corp) and as a result, a lot of the residues were confirmed in the through-hole group of the green color pattern as shown in Fig. 9.

Example 2

[Preparation of red radiation-sensitive composition]

A red radiation-sensitive composition was prepared by mixing the components shown below.

Pigment dispersion: Red pigment dispersion Rl shown below 51.2 parts

Photopolymerization initiator: IRGACURE OXE-01 (produced by 0.87 parts BASF)

Compound having heat-polymerizable group: KAYARAD RP- 1040 4.7 parts (produced by Nippon Kayaku Co., Ltd.)

Binder: ACA230AA (produced by Daicel Chemical Industries, Ltd.) 7.4 parts

Polymerization inhibitor: p-Methoxyphenol 0.002 parts

Additive: PIONIN D-6112-W (produced by Takemoto Oil & Fat Co., 0.19 parts Ltd.)

Solvent: PGMEA 14.3 parts

Solvent: Cyclohexanone 6.4 parts

(Preparation of Red pigment dispersion Rl)

A mixed solution composed of 8.3 parts by weight of C. I. Pigment Red 254 and 3.7 parts by weight of C. I. Pigment Yellow 139 as pigments, 4.8 parts by weight of BYK-161 (produced by BYK-Chemie) as a pigment dispersing agent and 83.2 parts by weight of PGMEA was mixed and dispersed in a bead mill for 15 hours to prepare Red pigment dispersion Rl .

[Formation of red radiation-sensitive layer]

A silicon (Bare-Si) substrate was placed on the hot plate and the red radiation-sensitive composition prepared as descried above was coated on the silicon (Bare-Si) substrate so as to have a thickness of 0.7 μπι. The coating was dried at 100°C for 2 minutes on the hot plate and cooled as it was at 23 °C for one minute on the hot plate to from a red radiation-sensitive layer.

The red radiation-sensitive layer thus-obtained was subjected to open frame exposure (whole surface exposure) using an i-ray stepper (FPA3000i5+, produced by Canon Inc.) in an

2

exposure amount of 800 mJ/cm .

Then, the stack after exposure was mounted on a horizontal rotary table of a spin shower developing machine (Model DW-30, produced by Chemitronics Co., Ltd.) and subjected to puddle development at 23 °C for 60 seconds using CD-2060 (produced by FUJIFILM Electronic Materials Co., Ltd.).

The resulting stack was again conveyed in the heating tank of the coater developer described above.

The stack was heated at 200°C for 5 minutes on the hot plate and then cooled at 23 °C to from a red cured layer.

[Preparation of blue radiation-sensitive composition]

A blue radiation-sensitive composition was prepared by mixing the components shown below.

Pigment dispersion: Blue pigment dispersion B 1 shown below 51.2 parts

Photopolymerization initiator: IRGACURE OXE-01 (produced by 0.87 parts

BASF)

Polymerizable compound: KAYARAD RP-1040 (produced by Nippon 4.7 parts

Kayaku Co., Ltd.)

Binder: ACA230AA (produced by Daicel Chemical Industries, Ltd.) 7.4 parts

Polymerization inhibitor: p-Methoxyphenol 0.002 parts

Additive: PIONIN D-6112-W (produced by Takemoto Oil & Fat Co., 0.19 parts

Ltd.) Silane coupling agent: 0.9% By weight cyclohexanone solution of 10.8 parts KBM-602 (produced by Shin-Etsu Chemical Co., Ltd.)

Solvent: PGMEA 14.3 parts

Solvent: Cyclohexanone 6.4 parts

Fluorine-based surfactant: 0.2% By weight cyclohexanone solution of 4.2 parts

F-781 (produced by DIC Corp.)

(Preparation of Blue pigment dispersion Bl)

A mixed solution composed of 9.5 parts by weight of C. I. Pigment Blue 15:6 and 2.4 parts by weight of C. I. Pigment Violet 23 as pigments, 5.6 parts by weight of BYK-161 (produced by BYK-Chemie) as a pigment dispersing agent and 82.5 parts by weight of PGMEA was mixed and dispersed in a bead mill for 15 hours to prepare Blue pigment dispersion Bl.

[Formation of blue color pattern]

The blue radiation-sensitive composition prepared as descried above was coated on the red cured layer so as to have a thickness of 0.7 μιη. The coating was dried at 100°C for 2 minutes on the hot plate and cooled as it was at 23 °C for one minute on the hot plate to from a blue radiation-sensitive layer.

The blue radiation-sensitive layer thus-obtained was subjected to pattern exposure using an i-ray stepper (FPA3000i5+, produced by Canon Inc.) in an exposure amount of 800 mJ/cm². The exposure pattern was a pattern wherein a plural number of square isolated patterns each having the length of one side of 1.4 μηι were arrayed in a square configuration (distance between the centers of square isolated patterns was 2.8 um).

Then, the stack after exposure was mounted on a horizontal rotary table of a spin shower developing machine (Model DW-30, produced by Chemitronics Co., Ltd.) and subjected to puddle development at 23°C for 60 seconds using CD-2060 (produced by FUJIFILM Electronic Materials Co., Ltd.).

Thus, the stack in which the blue color pattern was formed on the red cured layer was obtained.

The upper surface of the blue color pattern thus-obtained was observed using a critical dimension scanning electron microscope (S-9260, Mag: x 30.0k, HV/IP: 600v/8.0pA, produced by Hitachi High-Technologies Corp.) and as a result, the residue was hardly confirmed in the region other than the blue color pattern (that is, the red color region) as shown in Fig. 10.

Also, the relation between a wavelength and transmittance in the red cured layer before forming the blue radiation-sensitive layer was compared with the relation between a wavelength and transmittance in the red region of the stack after forming the blue color pattern. The results obtained are shown in Fig. 11.

At a wavelength of 450 nm, a wavelength of 550 nm and a wavelength at which the transmittance exhibits the minimum value in a wavelength range from 650 to 800 nm, the specific values of transmittance are shown in Table 1 below.

TABLE 1

Ref: Transmittance (TRef) (unit: %) in the red cured layer before forming the blue radiation-sensitive layer

After Color Mixing Test: Transmittance (Tp) (unit: %) in the red region of the stack after forming the blue color pattern.

As is apparent from Fig. 11 and Table 1, in Example 2 there is no large difference between the relation between a wavelength and transmittance in the red cured layer before forming the blue radiation-sensitive layer and the relation between a wavelength and transmittance in the red region of the stack after forming the blue color pattern, and it is confirmed that the spectral characteristic of the red region is not degraded even after forming the blue color pattern.

Comparative Example 2

A blue color pattern was formed in the same manner as in Example 2 except that the post-baking treatment in the formation of red radiation-sensitive layer was performed in the atmosphere by using a hot plate not having a function of nitrogen gas substitution.

The upper surface of the blue color isolated pattern thus-obtained was observed using a critical dimension scanning electron microscope (S-9260, Mag: x 30.0k, HV/IP: 600v/8.0pA, produced by Hitachi High-Technologies Corp.) and as a result, the residues as circled were confirmed in the region other than the blue color isolated pattern (that is, the red color region) as shown in Fig. 12.

Also, the relation between a wavelength and transmittance in the red cured layer before forming the blue radiation-sensitive layer was compared with the relation between a wavelength and transmittance in the red region of the stack after forming the blue color pattern. The results obtained are shown in Fig. 13.

At a wavelength of 450 nm, a wavelength of 550 nm and a wavelength at which the transmittance exhibits the minimum value in a wavelength range from 650 to 800 nm, the specific values of transmittance are shown in Table 2 below.

TABLE 2

As is apparent from Fig. 13 and Table 2, in Comparative Example 2 the difference between the relation between a wavelength and transmittance in the red cured layer before forming the blue radiation-sensitive layer and the relation between a wavelength and transmittance in the red region of the stack after forming the blue color pattern is larger than that in Example 2, and it is confirmed that the spectral characteristic of the red region is changed by the formation of blue color pattern.

From the above, it can be seen that by heating the transparent coating layer or colored pattern after the formation thereof in an environment where oxygen concentration of 100 ppm or less to from the transparent cured layer or colored cured pattern, even when other colored radiation-sensitive composition is provided thereon, the spectral characteristic is hardly changed so that a color filter having the excellent spectral characteristic can be produced.

This application is based on Japanese patent applications No. 2012-104212 filed on April 27, 2012, the entire content of which is hereby incorporated by reference, the same as set forth at length.

Claims

1. A method for forming a cured layer or cured pattern, comprising: heating, in an environment where oxygen concentration is 100 ppm or less, a coating layer formed by applying a polymerizable composition containing a compound having a heat-polymerizable group onto a substrate or a pattern formed by the coating layer.

2. The method for forming a cured layer or cured pattern as claimed in Claim 1, wherein the heating of the coating layer or the pattern is performed in a sealed heating tank in the presence of an inert gas.

3. The method for forming a cured layer or cured pattern as claimed in Claim 1 or 2, wherein the polymerizable composition is a transparent polymerizable composition.

4. The method for forming a cured layer or cured partem as claimed in any one of Claims 1 to 3, wherein the polymerizable composition further contains (i) a colorless transparent particle or (ii) at least one of a colored pigment and a dye.

5. The method for forming a cured layer or cured pattern as claimed in any one of Claims 1 to 4, wherein the heat-polymerizable group is a radical polymerizable group.

6. A method for producing a color filter, comprising the method for forming a cured layer or cured pattern as claimed in any one of Claims 1 to 5.

7. A color filter obtained by the method as claimed in Claim 6.

8. A solid-state imaging device comprising the color filter as claimed in Claim 7.

9. A liquid crystal display device comprising the color filter as claimed in Claim 7.