JP2012215843A - Method for forming pixel pattern, color filter, and display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a pixel pattern for significantly expressing superior chromaticity characteristics of dye and lake pigment when the dye and the lake pigment are used as colorants.SOLUTION: The method for forming a pixel pattern includes steps for: (1) forming on a substrate, a coating film of a colored radiation-sensitive composition including at least one type selected from a group consisting of dye and lake pigment; and (2) applying radiation to at least one part of the coating film. The spectral distribution of the radiation includes a plurality of peaks within a range of 350 nm to 450 nm, and the maximum strength of the radiation of less than 350 nm is 50% or less than the maximum peak strength within the range of 350 nm to 450 nm.

Description

  The present invention relates to a method for forming a pixel pattern, a color filter manufactured by this method, and a display element including the color filter.

  The color filter transmits light in a specific wavelength region of visible light to generate colored transmitted light. A liquid crystal display element using liquid crystal cannot develop color by itself, but can function as a color liquid crystal display element by using a color filter. The color filter is also used for color display of an organic EL (Electro Luminescence) element using a white light emitting layer, electronic paper, or the like. Furthermore, if a color filter is used, color imaging of a solid-state imaging device such as a CCD image sensor or a CMOS image sensor becomes possible.

  The following is known as a manufacturing method of a color filter. For example, a colored radiation-sensitive composition is applied on a transparent substrate or a transparent substrate on which a light-shielding layer having a desired pattern is formed, as a coloring composition that is sensitive to appropriate irradiation rays. Next, after the coating film is dried, the dried coating film is irradiated with radiation (hereinafter referred to as “exposure”) through a mask and subjected to a development treatment. This is a method for obtaining pixels of each color (see, for example, Patent Documents 1 and 2). Moreover, the method of obtaining the pixel of each color by the inkjet system using a colored curable resin composition is also known (for example, refer patent document 3).

  By the way, it is known that it is effective to use a dye or a lake pigment as a colorant in order to realize high brightness and high color purity of a display element or high definition of a solid-state imaging element (for example, And Patent Documents 4 and 5).

JP-A-2-144502 JP-A-3-53201 JP 2000-310706 A JP 2008-304766 A JP 2001-081348 A

  However, a colored radiation-sensitive composition containing a dye or a lake pigment is significantly inferior in process stability of chromaticity characteristics as compared with a colored radiation-sensitive composition containing only a pigment. Therefore, there is a problem that even if a dye or a lake pigment is used as the colorant, it is difficult to obtain a color filter having superior chromaticity characteristics over the pigment.

  The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a pixel pattern forming method for fully expressing the excellent chromaticity characteristics of the dye or the lake pigment when the dye or the lake pigment is used as the colorant. Another object of the present invention is to provide a color filter and a display device having the color filter and having excellent chromaticity characteristics.

  As a result of intensive studies, the present inventors have found that the above problem can be solved by using specific ultraviolet rays as exposure radiation when forming a pixel pattern.

  That is, the present invention includes (1) forming a coating film of a colored radiation-sensitive composition containing at least one selected from the group consisting of a dye and a lake pigment on a substrate, and (2) the coating film Irradiating at least a part of the radiation, the spectral distribution of the radiation has a plurality of peaks in the range of 350 nm to 450 nm, and the maximum intensity of the radiation below 350 nm is the maximum peak intensity at 350 nm to 450 nm. The present invention provides a method for forming a pixel pattern characterized by being 50% or less. In the following, “radiation having a spectral distribution having a plurality of peaks in the range of 350 nm to 450 nm and a maximum intensity below 350 nm being 50% or less of the maximum peak intensity at 350 nm to 450 nm” is referred to as “specific radiation”. Also called.

  In addition, the present invention provides a color filter including a pixel pattern formed by the above method, and a display element including the color filter.

  According to the present invention, when a dye or a lake pigment is used as a colorant, a color filter that can fully exhibit the excellent chromaticity characteristics of the dye or the lake pigment can be produced.

The figure which shows the typical spectral distribution of the radiation radiated | emitted from an ultrahigh pressure mercury lamp. The figure which shows the spectral distribution of the radiation obtained through the ultraviolet cut filter 1 to the radiation radiated | emitted from an ultrahigh pressure mercury lamp. The figure which shows the spectral distribution of the radiation obtained through the ultraviolet cut filter 2 to the radiation radiated | emitted from an ultrahigh pressure mercury lamp. The figure which shows the spectral distribution of the radiation obtained through the ultraviolet cut filter 3 to the radiation radiated | emitted from an ultrahigh pressure mercury lamp.

  Hereinafter, this embodiment will be described in detail.

<Pixel pattern forming method and color filter>
The pixel pattern forming method of the present invention includes at least the following steps (1) and (2).
(1) Forming a coating film of a colored radiation-sensitive composition containing at least one selected from the group consisting of a dye and a lake pigment on a substrate (hereinafter also referred to as “coating film forming process”).
(2) Step of exposing specific radiation to at least a part of the coating film (hereinafter also referred to as “exposure step”).

  Below, each process of (1) and (2) is demonstrated in detail, giving a specific example.

(1) Coating film forming step First, a substrate is prepared. As the substrate, for example, a transparent glass substrate such as borosilicate glass, aluminoborosilicate glass, alkali-free glass, quartz glass, synthetic quartz glass, soda lime glass, and white sapphire can be used. Also, acrylic such as polymethyl methacrylate, polyamide, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, triacetyl cellulose, syndiotactic polystyrene, polyphenylene sulfide, polyether ketone, polyether ether ketone, fluororesin, poly A transparent resin film such as ether nitrile, polycarbonate, modified polyphenylene ether, polycyclohexene, polynorbornene resin, polysulfone, polyethersulfone, polyarylate, polyamideimide, polyetherimide, or thermoplastic polyimide can also be used. In particular, alkali-free glass is a material having a small coefficient of thermal expansion, and is preferably used from the viewpoint of excellent dimensional stability and characteristics in high-temperature heat treatment.

  Moreover, on these substrates, if desired, in addition to chemical treatment and plasma treatment with a silane coupling agent, etc., a silicon dioxide film is formed by ion plating, sputtering, gas phase reaction or vacuum deposition, etc. Appropriate pretreatment can be applied.

  Next, a light-shielding layer (black matrix) is formed on the substrate so as to partition a portion where a pixel is to be formed. For example, a metal thin film such as chromium formed by sputtering or vapor deposition is processed into a desired pattern by using a photolithography method. Or you may apply | coat the radiation sensitive composition containing a black coloring agent on a board | substrate, and may form a desired pattern with the photolithographic method. The thickness of the light shielding layer made of a metal thin film is usually preferably 0.1 μm to 0.2 μm. On the other hand, the thickness of the light-shielding film formed using the black radiation-sensitive composition is preferably about 1 μm.

  In some cases, the light shielding layer is unnecessary, and in this case, the process of forming the light shielding layer can be omitted.

  Next, a negative blue radiation-sensitive composition containing, for example, a blue dye or a lake pigment is applied onto the substrate. Next, pre-baking is performed to evaporate the solvent, thereby forming a coating film.

  When the colored radiation-sensitive composition is applied to the substrate, a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or the like can be appropriately selected. From the viewpoint of obtaining a coating film having a uniform film thickness, it is preferable to employ a spin coating method or a slit die coating method.

  Pre-baking is usually performed by combining vacuum drying and heat drying. The drying under reduced pressure is usually performed until the pressure reaches 50 Pa to 200 Pa. Moreover, the conditions of heat drying are normally about 1 minute-10 minutes under the temperature of 70 to 110 degreeC using a hotplate. Moreover, the thickness of the coating film to apply | coat is 0.6 micrometer-8 micrometers normally as a film thickness after drying, Preferably it is 1.2 micrometers-5 micrometers.

  In addition, as another example of forming a coating film of a colored radiation-sensitive composition on a substrate, there is a method using an inkjet method disclosed in JP-A-7-318723, JP-A-2000-310706, and the like. It is done. In this method, first, a partition having a light shielding function is formed on the surface of the substrate. Next, a colored radiation-sensitive composition containing, for example, a blue dye or a lake pigment is discharged into the partition wall by an inkjet apparatus. Thereafter, pre-baking is performed to evaporate the solvent. The prebaking method and conditions are the same as in the first example.

  In addition, the above-mentioned partition fulfill | performs not only the light-shielding function but the function for the coloring radiation sensitive composition of each color discharged in the division not to be mixed. Therefore, the film thickness is thicker than the light shielding layer (black matrix) used in the first example. A partition is normally formed using a black radiation sensitive composition.

  Further, as a further example of forming a coating film of a colored radiation-sensitive composition on a substrate, there is a dry film method disclosed in JP-A-9-5991. In this method, a colored radiation-sensitive composition containing, for example, a blue dye or a lake pigment is applied on a film-like support, and pre-baked to evaporate the organic solvent, whereby the support is formed on the support. A dry film on which a colored radiation-sensitive composition layer is formed is produced. And the support body in which this colored radiation sensitive composition layer was formed is laminated | stacked on the board | substrate for color filter formation using a laminator. Thereafter, the colored radiation-sensitive composition layer is transferred to the substrate by peeling the colored radiation-sensitive composition layer from the support. The method for applying the colored radiation-sensitive composition on the support and the prebaking method and conditions are the same as those in the first example.

(2) Exposure step After the coating film forming step, at least a part of the formed coating film is usually exposed through a photomask having a predetermined pattern. The present invention is characterized in that the exposure radiation used at this time exhibits specific spectral characteristics. Usually, the radiation irradiated from the ultra high pressure mercury lamp used when manufacturing the color filter for color liquid crystal displays shows the spectral characteristics as shown in FIG. In FIG. 1, the peak at 436 nm is g-line, the peak at 405 nm is h-line, and the peak at 365 nm is i-line. It contains deep ultraviolet light with a peak of. The present inventors have found that the stability of dyes and lake pigments is increased by reducing the light intensity of less than 350 nm with respect to exposure radiation having such spectral characteristics, and have reached the present invention.

  In specific radiation, the maximum intensity at less than 350 nm is 50% or less of the maximum peak intensity at 350 nm to 450 nm, but is preferably 45% or less, and preferably 30% or less in order to enhance the desired effect. Further preferred.

  The specific radiation can be obtained using a lamp exhibiting the above-described spectral characteristics as a light source, but can also be obtained via an ultraviolet cut filter on radiation emitted from an ultrahigh pressure mercury lamp. The ultraviolet cut filter is not particularly limited as long as the light intensity of less than 350 nm can be reduced to the above conditions, and examples thereof include an ultraviolet cut filter UV-35, UV-33, UV-31 (manufactured by Toshiba Glass Co., Ltd.) and the like. Can do.

Exposure of a particular radiation is usually a 10~10,000J / m ^2, to enhance the desired effect is preferably 50~5,000J / m ^2, 100~2,000J / m ² is more preferable.

  After the exposure step, a step of (3) developing the coated film after exposure (hereinafter also referred to as “developing step”) and / or (4) a step of post-baking the coated film is performed as necessary.

(3) Development step After the exposure step, the unexposed portion of the coating film is dissolved and removed by developing with a developer. The developer is preferably an alkali developer, such as sodium carbonate, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, An aqueous solution such as 1,5-diazabicyclo- [4.3.0] -5-nonene is used. An appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, or the like can be added to the alkaline developer. Incidentally, after the alkali development treatment, washing with water is usually performed.

  As the development processing method, for example, a shower development method, a spray development method, a dip (immersion) development method, a paddle (liquid accumulation) development method, or the like can be applied. The development conditions can be, for example, 5 seconds to 300 seconds at room temperature.

  In addition, when the coating film of a colored radiation sensitive composition is formed by the said inkjet system, the image development process is unnecessary and abbreviate | omitted.

(4) Step of post-baking the coating film After the development step or after forming the coating film by the ink jet method and passing through the exposure step, it is preferable to post-bake the patterned coating film from the viewpoint of improving curability. . The conditions for the post-baking can be, for example, 150 ° C. to 250 ° C. for about 20 minutes to 40 minutes when a hot air heating furnace is used.

  In this way, a pixel array containing a blue dye or a lake pigment and having a blue pixel pattern arranged in a predetermined arrangement can be formed. Next, by using the negative type green radiation sensitive composition, by repeating the above process, a green image color pattern is formed on the same substrate, and further using the negative type red radiation sensitive composition, By repeating the above steps, a red pixel pattern is formed on the same substrate, whereby a pixel array in which pixel patterns of the three primary colors of red, green and blue are arranged in a predetermined arrangement can be formed on the substrate. . However, in this embodiment, the order in which the pixel patterns of the respective colors are formed on the substrate is not limited to the above example. The order of forming each color can be changed as appropriate.

  The film thickness of the pixel pattern formed as described above is usually 0.5 μm to 5 μm, preferably 1.0 μm to 3 μm.

  In the present invention, the pixel pattern constituting the color filter is not limited to red, green, and blue, but may be a pixel pattern having three primary colors of yellow, magenta, and cyan. In addition to the coloring patterns corresponding to the pixels of the three primary colors, the fourth and fifth coloring patterns can also be formed. For example, as disclosed in JP-T-2005-523465, etc., a fourth pixel (yellow pixel) for expanding the color specification range in addition to the coloring patterns corresponding to the three primary color pixels of red, green, and blue And a fifth pixel (cyan pixel) can be arranged.

  By providing a protective film on the pixel pattern thus formed, the display characteristics of the display element can be improved. Examples of the protective film include organic films or organic-inorganic hybrid films formed from curable compositions, or inorganic films such as SiNx films and SiOx films. In this Embodiment, it is preferable to form a protective film using a curable composition.

  As a method for forming a protective film using the curable resin composition, for example, a method disclosed in JP-A-4-53879 or JP-A-6-192389 can be employed.

  Examples of the curable resin composition used for forming the protective film include a thermosetting resin composition disclosed in JP-A-3-188153 or JP-A-4-53879, and JP-A-6-192389. And a polyorganosiloxane disclosed in Japanese Patent Application Laid-Open No. 2006-195420 or Japanese Patent Application Laid-Open No. 2008-208342. A curable composition etc. can be mentioned.

  According to the pixel pattern forming method of the present invention, excellent chromaticity characteristics of dyes and lake pigments can be exhibited without loss, that is, a pixel pattern having a small color difference (ΔE * ab) before and after exposure can be obtained. . Therefore, by using the pixel pattern forming method of the present invention, a color filter having excellent chromaticity characteristics can be obtained. The pixel pattern forming method of the present invention includes various colors such as a color filter for a color liquid crystal display element, a color filter for color separation of a solid-state image sensor, a color filter for an organic EL display element, and a color filter for electronic paper. It is suitable for manufacturing a filter, and particularly suitable for manufacturing a color filter for a color liquid crystal display element using a large substrate.

Next, the colored radiation-sensitive composition used in the pixel pattern forming method of the present invention will be described. The colored radiation-sensitive composition contains at least a colorant containing at least one selected from the group consisting of a dye and a lake pigment, a binder resin, a crosslinking agent, and a photopolymerization initiator. The colored radiation-sensitive composition is usually used as a liquid composition by blending a solvent.
Hereinafter, each component will be described.

  The colored radiation-sensitive composition used in the method for forming a pixel pattern of the present invention contains at least one selected from the group consisting of a dye and a lake pigment as a colorant. The dye is not particularly limited. For example, azo dyes, anthraquinone dyes, xanthene dyes, triarylmethane dyes, phthalocyanine dyes, quinoneimine dyes, quinoline dyes, nitro dyes, methine And dyes. Specific examples include those with the following color index (CI) names.

C. I. Acid Yellow 11, C.I. I. Acid Orange 7, C.I. I. Acid Red 37, C.I. I. Acid Red 180, C.I. I. Acid Blue 29, C.I. I. Solvent Red 89, C.I. I. Direct Red 28, C.I. I. Direct Red 83, C.I. I. Direct Yellow 12, C.I. I. Direct Orange 26, C.I. I. Direct Green 28, C.I. I. Direct Green 59, C.I. I. Reactive Yellow 2, C.I. I. Reactive Red 17, C.I. I. Reactive Red 120, C.I. I. Disperse Orange 5, C.I. I. Disperse thread 58, C.I. I. Disperse blue 165, C.I. I. Basic Blue 41, C.I. I. Basic Red 18, C.I. I. Molded Red 7, C.I. I. Azo dyes such as Moldant Yellow 5;

C. I. Bat Blue 4, C.I. I. Acid Blue 40, C.I. I. Acid Green 25, C.I. I. Reactive Blue 19, C.I. I. Reactive Blue 49, C.I. I. Disperse thread 60, C.I. I. Disperse Blue 56, C.I. I. Anthraquinone dyes such as Disperse Blue 60;
C. I. Basic Red 1, C.I. I. Basic Red 1: 1, C.I. I. Basic Violet 10, C.I. I. Xanthene dyes such as Solvent Red 49;
C. I. Basic Blue 7, C.I. I. Triarylmethane dyes such as Basic Blue 11;
C. I. Phthalocyanine dyes such as Pad Blue 5;
C. I. Basic Blue 3, C.I. I. Quinone imine dyes such as Basic Blue 9;
C. I. Solvent Yellow 33, C.I. I. Acid Yellow 3, C.I. I. Quinoline dyes such as Disperse Yellow 64;
C. I. Acid Yellow 1, C.I. I. Acid Orange 3, C.I. I. Nitro dyes such as Disperse Yellow 42;
C. I. Methine dyes such as Solvent Yellow 179.

  In addition, Claim 3 or Claim 4 of JP 2010-168531, JP 2010-170073, JP 2010-170074, JP 2010-275531, JP 2010-275533, etc. Azo dyes described in JP-A No. 2007-503477, claim 14 of Japanese Patent Publication No. 2007-503477, triarylmethane dyes described in International Publication No. 10/123071, pamphlet, etc. Examples thereof include xanthene dyes described in JP2010-244027A and JP2010-254964A.

Among these dyes, azo dyes, triarylmethane dyes, xanthene dyes, and methine dyes are preferable in that a particularly excellent effect can be obtained in the pixel pattern forming method of the present invention.
In this invention, dye can be used individually or in mixture of 2 or more types.

The lake pigment is a pigment that is insoluble with a precipitating agent. Examples of the precipitating agent include barium chloride, calcium chloride, ammonium sulfate, aluminum chloride, aluminum acetate, lead acetate, tannic acid, katanol, tamol, isopolyacid, heteropolyacid (for example, phosphotungstic acid, phosphomolybdic acid, phosphorous acid). Phosphotungstic molybdic acid, silicotungsten molybdic acid, silicotungstic acid, silicomolybdic acid) and the like. Among these, as the precipitant, isopolyacid and heteropolyacid are preferable.
Examples of such lake pigments include those having the following color index (CI) names.
C. I. Pigment blue 1, C.I. I. Pigment blue 2, C.I. I. Pigment blue 3, C.I. I. Pigment blue 9, C.I. I. Pigment blue 10, C.I. I. Pigment blue 14, C.I. I. Pigment blue 17: 1, C.I. I. Pigment blue 24, C.I. I. Pigment blue 24: 1, C.I. I. Pigment blue 56, C.I. I. Pigment blue 61, C.I. I. Pigment blue 62,
C. I. Pigment violet 1, C.I. I. Pigment violet 2, C.I. I. Pigment violet 3, C.I. I. Pigment violet 3: 1, C.I. I. Pigment violet 3: 3, C.I. I. Pigment violet 27, C.I. I. Pigment violet 39,
C. I. Pigment green 1, C.I. I. Pigment Green 4,
C. I. Pigment red 48: 1, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 48: 5, C.I. I. Pigment red 49, C.I. I. Pigment red 49: 1, C.I. I. Pigment red 49: 2, C.I. I. Pigment red 49: 3, C.I. I. Pigment red 52: 1, C.I. I. Pigment red 52: 2, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 54, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 58, C.I. I. Pigment red 58: 1, C.I. I. Pigment red 58: 2, C.I. I. Pigment red 58: 3, C.I. I. Pigment red 58: 4, C.I. I. Pigment red 60: 1, C.I. I. Pigment red 63, C.I. I. Pigment red 63: 1, C.I. I. Pigment red 63: 2, C.I. I. Pigment red 63: 3, C.I. I. Pigment red 64: 1, C.I. I. Pigment red 68, C.I. I. Pigment red 81, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 200, C.I. I. Pigment red 237, C.I. I. Pigment red 239, C.I. I. Pigment red 247,
C. I. Pigment yellow 61, C.I. I. Pigment yellow 61: 1, C.I. I. Pigment yellow 62, C.I. I. Pigment yellow 100, C.I. I. Pigment yellow 104, C.I. I. Pigment yellow 133, C.I. I. Pigment yellow 168, C.I. I. Pigment yellow 169, C.I. I. Pigment yellow 183, C.I. I. Pigment yellow 191, C.I. I. Pigment yellow 191: 1, C.I. I. Pigment yellow 206, C.I. I. Pigment yellow 209, C.I. I. Pigment yellow 209: 1, and C.I. I. Pigment yellow 212.

Of these lake pigments, C.I. I. Pigment blue 1, C.I. I. Pigment blue 2, C.I. I. Pigment blue 3, C.I. I. Pigment blue 9, C.I. I. Pigment blue 10, C.I. I. Pigment blue 14, C.I. I. Pigment blue 62, C.I. I. Pigment violet 1, C.I. I. Pigment violet 2, C.I. I. Pigment violet 3, C.I. I. Pigment violet 27, C.I. I. A triarylmethane lake pigment such as CI Pigment Violet 39 is preferable in that a particularly excellent effect can be obtained in the pixel pattern forming method of the present invention. Triarylmethane-based lake pigments having an isopolyacid or heteropolyacid as a precipitating agent are also disclosed in, for example, JP2011-150195A, JP2011-186043A, and the like.
In the present invention, the lake pigments can be used alone or in admixture of two or more.

  In the present invention, other colorants can be used as the colorant together with the dye and the lake pigment. Other colorants are not particularly limited, and colors and materials can be appropriately selected according to the use of the color filter. Specifically, any of organic pigments, inorganic pigments, and natural pigments can be used as a colorant, but organic pigments are preferably used because high color purity, luminance, and contrast are required.

  Preferable specific examples of the organic pigment include a color index (CI) name, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 224, C.I. I. Pigment red 242, C.I. I. Pigment red 254, C.I. I. Pigment green 7, C.I. I. Pigment green 36, C.I. I. Pigment green 58, C.I. I. Pigment blue 1, C.I. I. Pigment blue 15: 6, C.I. I. Pigment blue 80, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 139, C.I. I. Pigment yellow 150, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 211, C.I. I. Pigment orange 38, C.I. I. And CI Pigment Violet 23.

  The content of the colorant is usually 5 to 70% by mass, preferably 5 to 60% by mass in the solid content of the colored radiation-sensitive composition, from the viewpoint of forming a pixel having high luminance and excellent color purity. Solid content here is components other than the solvent mentioned later.

  The total content of at least one selected from the group consisting of dyes and lake pigments is preferably 5% by mass or more, particularly preferably 10% by mass or more, based on the total colorant.

  Although it does not specifically limit as binder resin in a colored radiation sensitive composition, It is preferable to contain the polymer which has an acidic functional group. Examples of the acidic functional group include a carboxyl group, a phenolic hydroxyl group, an imido acid group, a sulfo group, a sulfino group, and a sulfeno group. Of these, a carboxyl group is preferably used.

  Examples of the polymer having a carboxyl group include, for example, JP-A-5-19467, JP-A-6-230212, JP-A-7-140654, JP-A-7-207211, and JP-A-8-259876. JP-A-09-325494, JP-A-10-31308, JP-A-10-300902, JP-A-11-140144, JP-A-11-174224, JP-A-11-231523, Examples include polymers disclosed in Kaihei 11-258415, JP-A 2000-56118, JP-A 2002-296778, JP-A 2004-101728, and JP-A 2008-181095. it can.

The acid value of the binder resin is preferably 10 to 200 KOH / mg, more preferably 30 to 270 KOH / mg, and still more preferably 50 to 250 KOH / mg. Here, the “acid value” represents the number of mg of KOH required to neutralize 1 g of the solid content of the binder resin.
In this invention, binder resin can be used individually or in mixture of 2 or more types.

  The crosslinking agent in the colored radiation-sensitive composition is not particularly limited as long as it is a compound having two or more polymerizable groups. Examples of the polymerizable group include an ethylenically unsaturated group, an oxiranyl group, an oxetanyl group, and an N-alkoxymethylamino group.

  In the present invention, as the crosslinking agent, a compound having two or more (meth) acryloyl groups or a compound having two or more N-alkoxymethylamino groups is preferably used.

  Particularly preferred crosslinking agents include, for example, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, a compound obtained by reacting pentaerythritol triacrylate with succinic anhydride, dipenta A compound obtained by reacting erythritol pentaacrylate with succinic anhydride, a caprolactone-modified polyfunctional (meth) acrylate described in paragraphs [0015] to [0018] of JP-A-11-44955, N, N, N ′, N ′, N ″, N ″ -hexa (alkoxymethyl) melamine or N, N, N ′, N′-tetra (alkoxymethyl) benzoguanamine can be used.

  In this invention, a crosslinking agent can be used individually or in mixture of 2 or more types.

  The photopolymerization initiator in the colored radiation-sensitive composition is a compound capable of generating an active species capable of initiating the curing reaction of the above-mentioned crosslinking agent upon exposure to specific radiation.

  Preferred photopolymerization initiators include, for example, thioxanthone compounds, acetophenone compounds, biimidazole compounds, triazine compounds, O-acyloxime compounds, onium salt compounds, benzoin compounds, benzophenone compounds, α-diketones. Compounds, polynuclear quinone compounds, diazo compounds, imide sulfonate compounds, and the like.

  In the present invention, the photopolymerization initiator can be used in combination with a known sensitizer and a hydrogen donor. Moreover, a photoinitiator can be used individually or in mixture of 2 or more types.

  As long as the solvent in the colored radiation-sensitive composition disperses or dissolves each component constituting the colored radiation-sensitive composition and does not react with these components and has appropriate volatility, You can select and use.

In the present invention, preferred solvents include, for example, propylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, 3-methoxybutyl acetate, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexanone. 2-heptanone, 3-heptanone, 1,3-butylene glycol diacetate, 1,6-hexanediol diacetate, ethyl lactate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate , 3-methyl-3-methoxybutyl propionate, n-butyl acetate, i-butyl acetate, formic acid n- Mill, acetic i- amyl, n- butyl propionate, ethyl butyrate, i- propyl, and butyric acid n- butyl or ethyl pyruvate and the like.
In this invention, a solvent can be used individually or in mixture of 2 or more types.

  The colored radiation-sensitive composition can further contain other components. Other components include, for example, urethane dispersants, polyethylene imine dispersants, polyoxyethylene alkyl ether dispersants, polyoxyethylene alkyl phenyl ether dispersants, polyethylene glycol diester dispersants, sorbitan fatty acid ester dispersants. Dispersants such as polyester dispersants and acrylic dispersants; surfactants such as fluorine surfactants and silicon surfactants; vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane And adhesion promoters such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane. Kill.

<Display element>
The display element of this invention comprises the color filter manufactured by the method mentioned above. Specific examples of the display element include a color liquid crystal display element, an organic EL display element, and electronic paper.

  A color liquid crystal display element including a color filter manufactured by the method of the present invention includes, for example, a driving substrate on which a thin film transistor (TFT) is disposed, and a color filter according to the present embodiment. The substrate can be structured to face the liquid crystal layer. Alternatively, the color liquid crystal display element includes a substrate in which the color filter of this embodiment is formed on the surface of a driving substrate on which a thin film transistor (TFT) is disposed, and an ITO (Indium Tin Oxide) electrode. It is also possible to adopt a structure in which the substrate on which the film is formed faces the liquid crystal layer. The latter structure has the advantage that the aperture ratio can be remarkably improved, and a bright and high-definition liquid crystal display element can be obtained.

  The color liquid crystal display element includes a backlight unit. As the backlight unit, for example, a structure in which a fluorescent tube such as a cold cathode fluorescent lamp (CCFL) and a scattering plate are combined can be used. A backlight unit using a white LED as a light source can also be used. As the white LED, for example, a white LED that obtains white light by mixing a red LED, a green LED, and a blue LED, and a white light that is obtained by mixing a blue LED, a red LED, and a green phosphor to emit white light. A white LED that obtains white light by mixing white LEDs, a blue LED, a red light emitting phosphor, and a green light emitting phosphor to obtain white light by mixing colors, a white LED that obtains white light by mixing colors with a YAG phosphor, A combination of a blue LED, an orange light emitting phosphor, and a green light emitting phosphor to obtain white light by mixing colors, a white LED, an ultraviolet LED, a red light emitting phosphor, a green light emitting phosphor, and a blue light emitting phosphor And white LEDs that obtain white light by color mixing.

  The color liquid crystal display device including the color filter manufactured by the method of the present invention includes a TN (Twisted Nematic) type, a STN (Super Twisted Nematic) type, an IPS (In-Planes Switching) type, and a VA (Vertical Alignment) type. An appropriate liquid crystal mode such as an OCB (Optically Compensated Birefringence) type can be applied.

  An organic EL display element having a color filter manufactured by the method of the present invention can adopt an appropriate structure, and examples thereof include a structure disclosed in JP-A-11-307242.

  An electronic paper having a color filter manufactured by the method of the present invention can adopt an appropriate structure, and examples thereof include a structure disclosed in Japanese Patent Application Laid-Open No. 2007-41169.

  Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

[Preparation of pigment dye mixture, etc.]
Preparation Example 1
As a coloring agent, C.I. I. Pigment green 58 / C.I. I. Solvent Yellow 179 = 15 parts by mass of 60/40 (mass ratio) mixture, BYK-LPN21116 (by BYK) as a dispersant, 10 parts by mass (nonvolatile component = 40% by mass), and propylene glycol monomethyl ether acetate 75 as a solvent Mass parts were mixed and dispersed by a bead mill for 12 hours to prepare a pigment dye mixed solution (A1).

Preparation Example 2
As a coloring agent, C.I. I. Pigment Blue 15: 6 / C.I. I. 15 parts by weight of Basic Blue 7 = 60/40 (mass ratio) mixture, 10 parts by weight (non-volatile component = 40% by weight) of BYK-LPN21116 (produced by BYK) as a dispersant, and propylene glycol monomethyl ether acetate 75 as a solvent Mass parts were mixed and dispersed by a bead mill for 12 hours to prepare a pigment dye mixture (A2).

Preparation Example 3
As a coloring agent, C.I. I. Pigment Green 58 / Yellow dye (barbituric acid azo dye) represented by the following formula = 70/30 (mass ratio) mixture 15 parts by mass, BYK-LPN21116 (manufactured by BYK Corporation (BYK)) as a dispersant 10 parts by mass (Nonvolatile component = 40% by mass), and 75 parts by mass of propylene glycol monomethyl ether acetate as a solvent were mixed and dispersed by a bead mill for 12 hours to prepare a pigment dye mixture (A3).

Preparation Example 4
As a coloring agent, C.I. I. Pigment green 58 / C.I. I. Pigment Yellow 150 = 60/40 (mass ratio) 15 parts by mass of a mixture, BYK-LPN21116 (manufactured by BYK) as a dispersant, 10 parts by mass (nonvolatile component = 40% by mass), and propylene glycol monomethyl ether acetate 75 as a solvent Mass parts were mixed and dispersed by a bead mill for 12 hours to prepare a pigment dispersion (A4).

Preparation Example 5
As a coloring agent, C.I. I. Pigment Blue 15: 6 / C. I. Rhodamine 6G = 15 parts by mass of 60/40 (mass ratio) mixture, BYK-LPN21116 (produced by BYK) as a dispersant, 10 parts by mass (nonvolatile component = 40% by mass), and 75 parts by mass of propylene glycol monomethyl ether acetate as a solvent Parts were mixed and dispersed for 12 hours by a bead mill to prepare a pigment dye mixture (A5).

Preparation Example 6
As a coloring agent, C.I. I. Pigment Blue 15: 6 / Triarylmethane lake pigment represented by the following formula (wherein x = 1 to 2) = 60/40 (mass ratio) 15 parts by mass of the mixture, BYK-LPN21116 (BIC Chemie ( BYK)) 10 parts by mass (nonvolatile component = 40% by mass) and 75 parts by mass of propylene glycol monomethyl ether acetate as a solvent were mixed and dispersed for 12 hours by a bead mill to prepare a pigment dispersion (A6).

[Synthesis of binder resin]
Synthesis example 1
A flask equipped with a condenser and a stirrer was charged with 2 parts by mass of 2,2′-azobisisobutyronitrile and 200 parts by mass of propylene glycol monomethyl ether acetate, followed by 15 parts by mass of methacrylic acid and 20 parts by mass of N-phenylmaleimide. , 55 parts by mass of benzyl methacrylate, 10 parts by mass of styrene and 3 parts by mass of 2,4-diphenyl-4-methyl-1-pentene (manufactured by NOF Corporation, trade name: NOFMER MSD) as a molecular weight regulator, Replaced with nitrogen. Thereafter, the mixture was gently stirred to raise the temperature of the reaction solution to 80 ° C., and this temperature was maintained for 5 hours for polymerization to obtain a resin solution (solid content concentration = 33% by mass). The obtained resin was Mw = 16,000 and Mn = 7,000. This resin solution is referred to as “binder resin solution (B1)”.

Synthesis example 2
In a flask equipped with a condenser and a stirrer, 44 parts by mass of p-vinylbenzyl glycidyl ether, 40 parts by mass of N-phenylmaleimide, and 16 parts by mass of benzyl methacrylate are dissolved in 300 parts by mass of propylene glycol monomethyl ether acetate. 8 parts by mass of '-azobisisobutyronitrile and 8 parts by mass of 2,4-diphenyl-4-methyl-1-pentene were charged and purged with nitrogen. Thereafter, the reaction solution was heated to 80 ° C. while gently stirring and nitrogen bubbling, and polymerization was carried out for 5 hours while maintaining this temperature.
Next, 17 parts by weight of methacrylic acid, 0.5 parts by weight of p-methoxyphenol and 4.4 parts by weight of tetrabutylammonium bromide were added to the reaction solution, and the reaction was performed at a temperature of 120 ° C. for 9 hours. Furthermore, after adding 18.5 parts by mass of succinic anhydride and reacting at a temperature of 100 ° C. for 6 hours, the reaction solution temperature was maintained at 85 ° C. and washed twice with water, followed by concentration under reduced pressure to obtain a binder. A resin solution (solid content concentration = 33 mass%) was obtained. The obtained binder resin was Mw = 7,800 and Mn = 5,000. This binder resin solution is referred to as “binder resin solution (B2)”.

Example 1
(Preparation of colored radiation-sensitive composition)
100 parts by mass of pigment dye mixture (A1), 18 parts by mass of binder resin solution (B1) as a binder resin (solid content concentration = 33% by mass), KAYARAD MAX-3510 (dipentaerythritol manufactured by Nippon Kayaku Co., Ltd.) as a crosslinking agent 8 parts by mass of a mixture of hexaacrylate and dipentaerythritol pentaacrylate) and 4 parts by mass of KAYARAD DPCA-60 (caprolactone-modified dipentaerythritol hexaacrylate) manufactured by Nippon Kayaku Co., Ltd., 2-benzyl-2-dimethyl as a photopolymerization initiator 1 part by weight of amino-1- (4-morpholinophenyl) butan-1-one and ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) 3 parts by mass as a fluorosurfactant The DIC Corporation Megafac F-554 as a mixture of propylene glycol monomethyl ether acetate as 0.2 part by weight and a solvent to prepare a green radiation-sensitive composition with a solid content of 15% by mass.

[Formation of pixel pattern and evaluation of color stability]
The obtained green radiation-sensitive composition was applied on a glass substrate using a slit die coater and then pre-baked on a 90 ° C. hot plate for 4 minutes to form a coating film having a thickness of 2 μm.
Next, after the substrate on which the coating film was formed was cooled to room temperature, the radiation radiated from the ultrahigh pressure mercury lamp was obtained through the ultraviolet cut filter 1 (UV-31 (manufactured by Toshiba Glass Co.)), as shown in FIG. The coating film was exposed at a dose of 2,000 J / m ² through a striped photomask using radiation exhibiting spectral characteristics. Thereafter, a developer consisting of a 0.04 mass% potassium hydroxide aqueous solution at 23 ° C. was discharged at a development pressure of 1 kgf / cm ² (nozzle diameter 1 mm) on the obtained substrate, and shower development was performed for 1 minute. . Thereafter, this substrate was washed with ultrapure water and air-dried to form a green stripe pixel pattern on the substrate.
About the coating film before exposure and the formed pixel pattern, spectral characteristics were measured using a color analyzer (MCPD2000 manufactured by Otsuka Electronics Co., Ltd.), and a color difference (ΔE * ab) was obtained. The evaluation results are shown in Table 1.

Examples 2-11, Comparative Examples 1-5 and Reference Examples 1-2
In Example 1, each colored radiation-sensitive composition was prepared in the same manner as in Example 1 except that the type and content of each component were changed as shown in Table 1. Next, a pixel pattern was formed in the same manner as in Example 1 except that the exposure radiation was selected as shown in Table 1 using the obtained colored radiation-sensitive composition, and color stability was evaluated. . The evaluation results are shown in Table 1. The radiation having the spectral characteristics shown in FIG. 3 is obtained from the radiation radiated from the ultrahigh pressure mercury lamp through the ultraviolet cut filter 2 (UV-33 (manufactured by Toshiba Glass)), and the spectral characteristics shown in FIG. Is obtained through the ultraviolet cut filter 3 (UV-35 (manufactured by Toshiba Glass Co., Ltd.)) to the radiation emitted from the ultra-high pressure mercury lamp.

In Table 1, each component is as follows.
C1: caprolactone-modified dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name KAYARAD DPCA-60)
C2: monoesterified product of dipentaerythritol pentaacrylate and succinic acid, dipentaerythritol hexaacrylate and a mixture of dipentaerythritol pentaacrylate (manufactured by Toagosei Co., Ltd., trade name TO-1382)
C3: Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name KAYARAD MAX-3510)
C4: ethylene oxide oligomer-modified dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name KAYARAD DPEA-12)
D1: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one (product name: Irgacure 369, manufactured by Ciba Specialty Chemicals)
D2: Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) (trade name, manufactured by Ciba Specialty Chemicals) Irgacure OXE02)
D3: 2-mercaptobenzothiazole D4: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole (manufactured by Hodogaya Chemical Co., Ltd., product) Name B-CIM)
D5: 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., trade name CAYACURE DETX-S)
D6: 4,4′-bis (diethylamino) benzophenone D7: “trade name NCI930” manufactured by ADEKA

Claims (3)

  (1) forming a coating film of a colored radiation-sensitive composition containing at least one selected from the group consisting of a dye and a lake pigment on a substrate; and (2) radiation on at least a part of the coating film. The spectral distribution of the radiation has a plurality of peaks in the range of 350 nm to 450 nm, and the maximum intensity of the radiation below 350 nm is 50% or less of the maximum peak intensity at 350 nm to 450 nm. A method of forming a pixel pattern, characterized in that   A color filter comprising a pixel pattern formed by the method according to claim 1.   A display element comprising the color filter according to claim 2.

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