Chemical amplification resist composition.

0001The present invention relates to a chemical amplification resist composition which is high sensitive, in particular, to from visible to near infrared rays and from which the positive and negative type resist can be obtained.

0002A chemical amplification resist composition which can forms the pattern by producing a secondary chemical reaction with the catalytic action of an acid formed by exposure to light using a photochemical acid generator as a sensitizing agent, and thereby causing the change in the solubility in the developer is known [J. Synthetic Org. Chem., Japan, 49, 437 (1991), ), SEN-I GAKKAISHI, 47, 358 (1991)].

0003On the other hand, the squarylium compounds are known to be used for the resist material in the presence of an ethylenic unsaturated compound (JP-A-63-142346, JP-A-2-306247), the image formation system in the presence of light-unstable blocked surfactant (JP-A-60-243653), a charge generation material in the electrophotography (Dyes and Pigments, 9, 85 (1988), JP-A-52-55643, JP-A-60-224674), the medium material for optical memory disc (JP-A-3-149263), the resin plate material for beam-condensing (JP-A-63-235370), LB (Langmuir-Brodget) membrane material (Nikkei New Material, published October, 26, 1987) and the like.

0004The main object of the invention is to provide a chemical amplification resist composition which is high sensitive, in particular, to from visible to near infrared rays and from which the positive and negative type resist can be obtained.

0005This object has been achieved by providing a chemical amplification resist composition which comprises squarylium compounds represented by the formula (I): <chemistry id="chem0001" num="0001"><img file="EP0568993A2_D0001.tif" /></chemistry> wherein R¹ and R² are the same or different and represent substituted or unsubstituted aminophenyl, 9- julolidyl, Y=CH-(wherein Y is substituted or unsubstituted heterocyclic group containing nitrogen), or a group represented by the formula: <chemistry id="chem0002" num="0002"><img file="EP0568993A2_D0002.tif" /></chemistry> (wherein Z¹ and Z² are the same or different and represent substituted or unsubstituted phenyl), photochemical acid generators and binders.

0006As the heterocyclic group containing nitrogen in the formula (I), there are indolin-2-ylidene, benz[e]-indolin-2-ylidene, 2-benzothiazolinylidene, naphtho[2,1-d]thiazol-2(3H)-ylidene, naphtho[1,2-d]thiazol-2(1H)-ylidene, 1,4-dihydroquinolin-4-ylidene,1, 2-dihydroquinolin-2-ylidene, 2, 3-dihydro-1 H-imidazo[4,5-b]-quinoxalin-2-ylidene, 2-benzoselenazolinylidene and the like.

0007Aminophenyl, phenyl, 9-julolidyl and heterocyclic groups containing nitrogen are optionally substituted with the same or different one to three substituents. As the substituent, there are alkyl, alkoxy, aryl, aralkyl, halogen, nitro, hydroxy, amino and the like.

0008As the alkyl group, there is the alkyl having 1 to 6 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, amyl, hexyl and the like.

0009As the alkoxy group, there is the alkoxy having 1 to 6 carbon atoms, for example, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and the like.

0010As the aryl group, there is the aryl having 6 to 10 carbon atoms, for example, phenyl, naphthyl and the like. As the aralkyl, there is the aralkyl having 7 to 10 carbon atoms, for example, benzyl, phenylethyl, phenylpropyl and the like. As the halogen, there are fluorine, chlorine, bromine and iodine.

0011The squaryliums [compounds (I)] are the known compounds (see, for example, JP-A-63-142346 and JP-A-2-306247) and the novel compounds. Those compounds are prepared, for example, by the following method.

Preparation 1

0012<chemistry id="chem0003" num="0003"><img file="EP0568993A2_D0003.tif" /></chemistry>squarlic acid - compound (I) wherein R¹ and R² are as defined above, X represents chlorine, bromine, iodine or a group: <chemistry id="chem0004" num="0004"><img file="EP0568993A2_D0004.tif" /></chemistry>

0013This reaction is carried out by reacting R¹H (or R¹H₂⁺•X^-),the equivalent moles of R²H (or R²H₂⁺•X^-) and the equivalent moles of squarlic acid and, if necessary, from equivalent to 2 times moles of a basic compound at 90 to 110 °C for 1 to 24 hours in a solvent. As the solvent, an alcoholic solvent is used sole or in admixture with benzene or toluene (alcohol is not less than 50%). Alternatively, acetic acid is used as a solvent.

0014As the basic compound, there are triethylamine, quinoline, pyridine and the like.

0015The solvent is distilled off from the reaction mixture or the product is filtered to give a compound (I).

Preparation 2

0016<chemistry id="chem0005" num="0005"><img file="EP0568993A2_D0005.tif" /></chemistry> wherein R¹, R² and X are as defined above, R⁰ represents chlorine or OR³ (wherein R³ represents alkyl having 1 to 4 carbon atoms).

0017As the alkyl having 1 to 4 carbon atoms, there are methyl, ethyl, propyl, butyl and the like.

0018A compound (III) is prepared by reacting R¹H (or R¹H₂⁺•X^-) and the equivalent moles of a compound (II) and, if necessary, the equivalent moles of a basic compound or metallic sodium at 10 to 35 _°C for 5 minutes to 5 hours in a solvent.

0019As the basic compound, those described above can be used. As the solvent, there are chloroform, dichloromethane, 1,2-dichloroethane, diethyl ether, diisopropyl ether, tetrahydrofuran, toluene, benzene, dimethylformamide, dimethyl sulfoxide, methanol, ethanol, propanol, butanol and the like.

0020The compound (III) is isolated by distilling the solvent off or filtering the product.

0021A compound (IV) is prepared by reacting a compound (III) at 90 to 110 °C for 1 to 24 hours in a 50 to 90 (wt.%) aqueous solution of acetic acid. The compound (IV) is isolated as described above.

0022A compound (I) is prepared by reacting a compound (IV) and the equivalent moles of R²H (or R²H₂⁺•X^-) and, if necessary, the equivalent moles of a basic compound at 90 to 110 °C for 1 to 24 hours in a solvent. As the basic compound, the above compounds can be used. As the solvent, an alcoholic solvent is used sole or in admixture with benzene or toluene (alcoholic solvent is not less than 50%).

0023The compound (I) is isolated as described above. And the compound (I) can be further purified by recrystallization, forced precipitation, column chromatography and the like.

0024Then, the representative compounds (I) are shown in Table 1. <tables id="tabl0001" num="0001"><img file="EP0568993A2_D0006.tif" /></tables><tables id="tabl0002" num="0002"><img file="EP0568993A2_D0007.tif" /></tables>

0025As the photochemical acid generator, there are s-triazine compounds substituted with at least one trihalomethyl groups [such as 2,4,6-tris(trichloromethyl)-s-triazine, 2-(4-methoxyphenyl)-4,6-bis-(trichloromethyl)-s-triazine, 2-(4-methoxy-1-naphthalenyl)-4,6-bis(trichloromethyl)-s-triazine and the like], iron-arene complexes [such as a salt of PF₆₈ of (η⁶-isopropylbenzene) (η⁵-cyclopentadienyl)iron (II) and the like], onium salts {such as diaryliodonium salts [8-anilinenaphthalen-1-sulfonic acid diphenyliodonium salts and the like], triarylsulfonium salts, triarylselenonium salts, dialkylphenacylsulfonium salts, dialkyl-4-hydroxyphenylsulfonium salts, iodonium salts and the like), aryldiazonium salts, diazoketones, o-nitrobenzyl esters [such as 9,10-diethoxyanthracen-2-sulfonic acid-p-nitrobenzyl esters] and the like], sulfonic acid esters [such as a-hydroxymethylbenzoinsulfonic acid ester, N-hydroxyimidosulfonate and the like], silanol-aluninium complexes and the like. Among them, s-triazine compounds substituted with at least one trihalomethyl groups are preferable and they can be obtained, for example, according to the method described in JP-A-2-306247.

0026As the binder, there are acrylic acid or ester thereof, methacrylic acid or ester thereof, (anhydrous) maleic acid or ester thereof, acrylonitrile, styrene, a-alkylstyrene, a-acetoxystyrene, hydroxystyrene, a-alkylhydroxystyrene, a-acetoxyhydroxystyrene, or the substituted compounds obtained by protecting the hydroxy groups of the above compounds with a protecting group easily hydrolyzable by acid treatment (for example, trialkylsilyl group, tetrahydropyranyl group, t-butoxycarbonyl group and the like), or cyclic analogues thereof, vinyl acetate, vinyl chloride, vinylidene chloride, butadiene, crotonic acid, itaconic acid, N-substituted maleimide, vinyl benzoate, or copolymer of the above esters, polyethylene oxide, polyvinyl pyrrolidone, polyamide, polyurethane, polyethylene terephtalate, acetyl cellulose, methyl cellulose, ethyl cellulose, polyvinyl butyral, chlorinated polyolefine, polyalkylene, polyaldehyde, polycarbonate, epoxy resin, cresol novolak resin, melamine resin, alkyd resin, modified polyvinyl alcohol, or block or graft copolymer or modified polymer by combination of them and the like.

0027For improving the plasma-resistance upon development, an substituent containing silicone may be introduced in the binder before or after exposure to light.

0028The proportion of the compound (I) is 1 to 60 parts by weight (referred to as "part" hereinafter) relative to 100 parts of photochemical acid generator, and the amount of the binder is 2 to 100 parts, preferably 5 to 50 parts, relative to one part of the photochemical acid generator.

0029In particular, when the negative type resist is prepared by the thermal cross-linking reaction in the presence of an acid, a cross linking agent may be contained therein.

0030As the cross linking agent, there are amino compounds having as a functional group at least two alkoxymethyl group, methylol group, acetoxymethyl group and the like such as melamine derivative [hexamethoxymethylated melamine (manufactured by MITSUI-CYANAMID, LTD., CYMEL @ 300 series (1) )and the like], benzoquanamine derivative [methyl/ethyl mixed alkylated benzoguanamine resin (manufactured by MITSUI-CYANAMID, LTD., CYMEL @ 1100 series (2) )and the like], glycoluril derivative [tetramethylolglycoluril (manufactured by MITSUI-CYANAMID, LTD., CYMEL @ 1100 series (3)) and the like], at least disubstituted aromatic compounds having, as a functional group, alkoxymethyl group, methylol group, acetoxymethyl group and the like such as 1,3,5-trihydroxymethylbenzene, 1,3,5-triacetoxymethylben- zene, 1,2,4,5-tetraacetoxymethylbenzene and the like. These cross linking agents can be synthesized according to the method described in Polym. Mater. Sci. Eng., 64, 241 (1991).

0031The amount of the cross linking agent is 0.1 to 100 parts, preferably 0.2 to 50 parts, relative to one part of the photochemical acid generator.

0032Further, solvent (such as ethyl cellosolve and the like), dissolution inhibiting agent (such as silyl ether and the like), plasticizer (such as dioctyl phthalate and the like), sensitivity improving agent (such as tertiary amine and the like), dark reaction inhibitor, colorant composed of organic or inorganic dye or pigment and the like may be contained therein depending upon the use of the chemically amplifying resist.

0033The chemical amplification resist composition of the present invention is prepared, for example, by mixing the compound (I), the photochemical acid generator and the binder and, if necessary, cross linking agent and the like. Further, a photosensitive material having the high sensitivity to, in particular, from visible to near infrared rays can be obtained by coating a solution of the chemical amplification resist composition of the present invention dissolved in a solvent (such as ethyl cellosolve and the like) on the aluminium plate having the treated surface, silicon wafer, glass plate and the like and drying.

0034As the light source for from visible to near infrared rays, the source for the rays which can be absorbed by the compound (I) such as mercury lamp, carbon arc lamp, xenon lamp, metal halide lamp, fluorescent lamp, tungsten lamp, halogen lamp, light-emitting diode, laser rays and the like can be used.

0035The temperature at heat-treating following the light irradiation is not higher than the melting point (decomposition point) of a photosensitive material obtained at room temperature, most preferably 50 to 120 °C. Upon development for final image formation, the wet development using a solvent (for example, dilute aqueous alkaline solution and the like) and dry etching using heating, plasma, accelerated ion and the like can be used depending upon the composition of the photosensitive material.

0036The following Examples and Reference Examples further illustrate the present invention in detail but are not to be construed to limit the scope thereof.

Example 1

0037100 Parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co. Ltd., Resin M], 40 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL @ 301 8 8 parts of 2,4,6-tris(chloromethyl)-s-triazine and 1 part of the compound 1 were dissolved in 900 ml of ethyl cellosolve to give a solution of a chemical amplification resist composition. This solution was coated on the aluminium plate which had been treated by graining and anodic oxidation using a spin-coater and dried using a warm air drier to give the dry-state thickness of 1 µm. A step tablet having the optical density step of 0.15 was piled on the resulting photosensitive sample, and the rays (lo =80.5 µJ/cm²•s) having the wavelength around 630 nm were irradiated from 3 KW ultra-high pressure mercury lamp through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation), a colored glass filter R-61 and an interference filter [both filters are manufactured by Toshiba Glass Co., Ltd.]. Subsequently, the heat-treating was carried out in an oven at 100 °C for 5 minutes, the development was carried out using an aqueous solution containing 2 wt% sodium metasilicate, the ink was applied using the ink PI-2 for PS form plate development [manufactured by Fujiphoto Film Co., Ltd.], and the necessary energy for curing was calculated from the curing step number with the ink applied to give the high sensitivity of 0.7 mJ/cm^2.

Example 2

0038The sensitivity of 1.4 mJ/cm² was obtained according to the same manner as that in Example 1 except that one part of the compound 4 and heat treating conditions (90 °C, 10 minutes) were used in place of one part of the compound 1 and the heat treating conditions (100 °C, 5 minutes).

Example 3

0039The very high sensitivity of 0.24 mJ/cm² was obtained according to the same manner as that in Example 1 except that the heat treating conditions (90 °C, 10 minutes) were used in place of (100 °C, 5 minutes).

Example 4

0040The sensitivity of 3.4 mJ/cm² was obtained according to the same manner as that in Example 1 except that 8 parts of

PF

68

0041salt of (η⁶-isopropylbenzene) (η⁵-cyclopentadienyl) iron (II) was used in place of 8 parts of 2,4,6-tris-(trichloromethyl)-s-triazine.

Example 5

0042The sensitivity of 4 mJ/cm² was obtained according to the same manner as that in Example 1 except that one part of the compound 3 and the heat treating conditions (90 °C, 10 minutes) were used in place of one part of the compound 1 and heat treating conditions (100 °C, 5 minutes).

Example 6

0043The sensitivity of 4.5 mJ/cm² was obtained according to the same manner as that in Example 1 except that one part of the compound 2 and heat treating conditions (90 °C, 10 minutes) were used in place of one part of the compound 1 and heat treating conditions (100 °C, 5 minutes).

Example 7

0044The sensitivity of 5 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., PHS MARUKA LYNCUR H3F], one part of the compound 6 obtained in Reference Example 1 and the heat treating conditions (90 °C, 10 minutes) were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M], one part of the compound 1 and the heat treating conditions (100 °C, 5 minutes), and the rays (lo = 2.46 mJ/cm^2.s) having the wavelength around 600 to 800 nm were irradiated without using an interference filter KL-63 [manufactured by Toshiba Glass Co., Ltd.].

Example 8

0045The sensitivity of 5 mJ/cm² was obtained according to the same manner as that in Example 7 except that one part of the compound 7 obtained in Reference Example 2 was used in place of one part of the compound 6 obtained in Reference Example 1.

Example 9

0046The sensitivity of 18 mJ/cm² was obtained according to the same manner as that in Example 7 except that one part of the compound 5 was used in place of one part of the compound 6 obtained in Reference Example 1.

Example 10

0047The sensitivity of 0.9 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of polymethacrylic acid ester polymer and the heat treating conditions (90 °C, 6 minutes) were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M] and the heat treating conditions (100 °C, 5 minutes).

Example 11

0048A photosensitive sample having the dry-state thickness of 1 µm was obtained by spin-coating on the glass having the treated surface a solution of a chemical amplification resist composition prepared according to the same manner as that in Example 1 except that 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., PHS MARUKA LYNCUR H3F] and 40 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL ⁰ 300] were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M] and 40 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL ⁰ 301 and drying. The He-Ne laser rays were split into two light flux using a beam splitter and the two light flux were introduced in the photosensitive sample from the same plane at the angle Θ=74 °. After exposure to light, the photosensitive sample was heat-treated in an oven at 90 °C for 15 minutes, subsequently developed with an aqueous solution containing 2 wt% sodium metasilicate, washed with water and dried to give the bright surface hologram.

Example 12

0049The sensitivity of 0.7 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of metacresol novolak resin (m/p=6/4) and the heat treating conditions (90 °C, 10 minutes) were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M] and the heat treating conditions (100 °C, 5 minutes).

Example 13

0050The sensitivity of 6 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of styrene-maleic acid monoisobutyl copolymer and the heat treating conditions (90 °C, 1 minute) were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M] and the heat treating conditions (100 °C, 5 minutes).

Example 14

0051The sensitivity of 43 mJ/cm² was obtained according to the same manner as that in Example 7 except that 42 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL ® 300], 9 parts of 8-anilinenaphthalen-1-sulfonic acid diphenyliodonium salt, one part of the compound 1 and the heat treating conditions (90 °C, 6 minutes) were used in place of 40 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL ® 301 8 parts of 2,4,6-tris(trichloromethyl)-s-triazine, one part of the compound 6 obtained in Reference Example 1 and the heat treating conditions (90 °C, 10 minutes).

Example 15

0052The sensitivity of 3 mJ/cm² was obtained according to the same manner as that in Example 1 except that 8 parts of 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine and the heat treating conditions (90 °C, 12 minutes) were used in place of 8 parts of 2,4,6-tris(trichloromethyl)-s-triazine and the heat treating conditions (100 °C, 5 minutes).

Example 16

0053100 Parts of alkali-insoluble polyimide containing fluorine in which the hydroxy group is protected with tetrahydropyranyl group, 8.4 parts of 2,4,6-tris(trichloromethyl)-s-triazine and 0.9 parts of the compound 1 were dissolved in 900 ml of ethyl cellosolve to give a solution of chemical amplification resist composition. This solution was coated on the aluminium plate treated with graining and anodic oxidation using a spin-coater, and dried using a warm air drier to give the dry-state thickness of 1 µm. A step tablet having the optical density step of 0.15 was piled on the resulting photosensitive sample, and the rays having the wavelength around 610 nm were irradiated from 3KW ultra-high pressure mercury lamp through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation) and a colored glass filter R-61 [manufactured by Toshiba Glass Co., Ltd.]. The photosensitive sample was subsequently heat-treated in an oven at 120 _°C for 15 minutes, and developed with DN3C developer for PS form plate [manufactured by Fujiphoto Film Co., Ltd.], upon which the irradiated parts were dissolved to give a positive image.

Example 17

0054The sensitivity of 2.0 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., PHS MARUKA LYNCUR H3F], 40.8 parts of hexamethoxymethylated melamine [manufactured by K&amp;K], 7.6 parts of 2,4,6- tris(trichloromethyl)-s-triazine, 1.02 parts of the compound 6 obtained in Reference Example 1, the rays (l_o= 162 µJ/cm²•s) having the wavelength around 780 nm obtained by irradiating from 3KW ultra-high pressure mercury lamp and passing through KL-78 [manufactured by Toshiba Glass Co., Ltd.] and the heat treating conditions (90 °C, 10 minutes) were used in place of 100 parts of poly-p-hydroxystyrene [manufactured by Maruzen Petrochemical Co., Ltd., Resin M], 40 parts of hexamethoxymethylated melamine [manufactured by MITSUI-CYANAMID, LTD., CYMEL ⁰ 301 8 parts of 2,4,6-tris(trichloromethyl)-s-triazine, one part of the compound 1, the rays (lo = 80.5 µJ/cm²•s) having the wavelength around 630 nm obtained by irradiating from 3 KW ultra-high pressure mercury lamp and passing through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation), a colored glass filter R-61 and an interference filter KL-63 [both filters are manufactured by Toshiba Glass Co., Ltd.].

Example 18

0055The sensitivity of 1.36 mJ/cm² was obtained according to the same manner as that in Example 17 except that 1.25 parts of the compound 7 obtained in Reference Example 2 and the heat treating conditions (90 _°C, 11 minutes) were used in place of 1.02 parts of the compound 6 obtained in Reference Example 1 and the heat treating conditions (90 °C, 10 minutes).

Example 19

0056The sensitivity of 3.1 mJ/cm² was obtained according to the same manner as that in Example 17 except that 1.1 parts of the compound 8 obtained in Reference Example 3 and the heat treating conditions (90 °C, 13 minutes) were used in place of 1.02 parts of the compound 6 obtained in Reference Example 1 and the heat treating conditions (90 °C, 10 minutes).

Example 20

0057The sensitivity of 3.4 mJ/cm² was obtained according to the same manner as that in Example 1 except that 100 parts of poly-p-hydroxystyrene (manufactured by Maruzen Petrochemical Co., Ltd., PHS MARUKA LYNCUR H3F), 48 parts of hexamethoxymethylated melamine (manufactured by K&amp;K), 1.1 parts of the compound 9 obtained in Reference Example 4 and the heat treating conditions (90 °C, 8 minutes) were used in place of 100 parts of poly-p-hydroxystyrene (manufactured by Maruzen Petrochemical Co., Ltd., Resin M), 40 parts of hexamethoxymethylated melamine (manufactured by MITSUI-CYANAMID, LTD., CYMEL ⁰ 301), one part of the compound 1 and the heat treating conditions (100 °C, 5 minutes).

Example 21

0058The sensitivity of 1.9 mJ/cm² was obtained according to the same manner as that in Example 20 except that 1.1 parts of the compound 10 having the following structure was used in place of 1.1 parts of the compound 9 obtained in Reference Example 4.

0059The compound 10 is known (see, for example, JP-A-2-306247). <chemistry id="chem0006" num="0006"><img file="EP0568993A2_D0008.tif" /></chemistry>

Example 22

0060The sensitivity of 4.9 mJ/cm² was obtained according to the same manner as that in Example 20 except that 40 parts of hexamethoxymethylated melamine (manufactured by K&amp;K), 1.0 part of the compound 11, the rays (l_o = 2.55 mJ/cm²•s) having the wavelength of not less than 660 nm obtained by irradiating from 3KW ultra-high pressure mercury lamp and passing through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation) and a colored glass filter R-66 (manufactured by Toshiba Glass Co., Ltd.) and the heat treating conditions (90 °C, 18 minutes) were used in place of 48 parts of hexamethoxymethylated melamine (manufactured by K&amp;K), 1.1 parts of the compound 9, the rays (l_o =80.5 µJ/cm²•s) having the wavelength around 630 nm obtained by irradiating from 3KW ultra-high pressure mercury lamp and passing through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation), a colored glass filter R-61 and an interference filter KL-63 (both filters are manufactured by Toshiba Glass Co., Ltd.) and the heat treating conditions (90 _° C, 8 minutes).

Example 23

0061The sensitivity of 3.3 mJ/cm² was obtained according to the same manner as that in Example 20 except that 40 parts of hexamethoxymethylated melamine (manufactured by K&amp;K), 1.0 part of the compound 12, the rays (lo = 112 µJ/cm²•s) having the wavelength around 680 nm obtained by irradiating from 3KW ultra-high pressure mercury lamp and passing through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation), a colored glass filter R-66 and an interference filter KL-68 (both filters are manufactured by Toshiba Glass Co., Ltd.) and the heat treating conditions (90 °C, 5 minutes) were used in place of 48 parts of hexamethoxymethylated melamine (manufactured by K&amp;K), 1.1 parts of the compound 9, the rays (lo = 80.5 µJ/cm²•s ) having the wavelength around 630 nm obtained by irradiating from 3 KW ultra-high pressure mercury lamp and passing through a heat rays absorbing filter HA-30 (manufactured by HOYA Corporation), a colored glass filter R-61 and an interference filter KL-63 (both filters are manufactured by Toshiba Glass Co., Ltd.) and the heat treating conditions (90 °C, 8 minutes).

0062The compound 12 having the following structure is known (see, for example, JP-A-3-149263). <chemistry id="chem0007" num="0007"><img file="EP0568993A2_D0009.tif" /></chemistry>

Reference Example 1

006315 ml of dichloromethane was added to 0.3 g of 3,4-dichloro-3-cyclobuten-1,2-dione [Tetrahedron Lett. No. 10, P.781 (1970)], and 0.54 g of 1,1-bis(p-dimethylaminophenyl)ethylene was added thereto to stir at room temperature. After 1 hour, the dichloromethane was distilled off from the reaction mixture using a rotary evaporator. 7.6 ml of acetic acid and 10 ml of water were added to the residue and the mixture was heated on an oil bath at 100 °C. After heating for 1 hour, the acetic acid and water were distilled off using a rotary evaporator. 20 ml of n-butanol and 20 ml of benzene as well as 1.05 g of 1,3-di-n-hexyl-2-methylimidazo[4,5-b]quinoxalinium tosylate and 0.27 g of quinoline were added to the residue and the mixture was heated for 2 hours. Thereafter, the mixture was concentrated using a rotary evaporator, and purified by column chromatography to give 0.45 g of a compound 6.

0064The melting point and the results of elementary analysis are as follows. Melting point: 147 _°C (dec.) <tables id="tabl0003" num="0003"><img file="EP0568993A2_D0010.tif" /></tables>

Reference Example 2

0065A mixture of 1.98 g of 3,4-diisopropoxy-3-cyclobuten-1,2-dione, 2.99 g of N-ethyllepidinium iodide and 20 ml of isopropanol was stirred at room temperature, 0.23 g of sodium was added thereto and the mixture was stirred for 4 hours. The insolubles were filtered, the filtrate was concentrated, and the residue was purified by column chromatography. 30 ml of acetic acid and 10 ml of water were added to this purified material, and the mixture was heated at 95 _°C for 1.5 hours. After completion of the reaction, the volatile portion was concentrated and dried. 13 ml of n-butanol and 0.92 g of 1,3-di-n-butyl-2-methylimidazo[4,5-b]-quinoxalinium chloride and 0.27 g of quinoline were added to the dried material, and the mixture was heated to reflux for 4 hours. The solvent and produced water were distilled off using a rotary evaporator. The residue was purified by column chromatography to give 0.31 g of a compound 7.

0066The melting point and the results of elementary analysis are as follows. Melting point: 237-238 _° C (dec.) <tables id="tabl0004" num="0004"><img file="EP0568993A2_D0011.tif" /></tables>

Reference Example 3

0067A mixture of 1.98 g of 3,4-diisopropoxy-3-cyclobuten-1,2-dione, 2.99 g of N-ethyllepidinium iodide and 20 ml of isopropanol was stirred at room temperature, 0.23 g of sodium was added thereto, and the mixture was stirred for 4 hours. The insolubles were filtered, the filtrate was concentrated, and the residue was purified by column chromatography.

006830 ml of acetic acid and 10 ml of water were added to this purified material, and the mixture was heated at 90-100 °C for 1.5 hours. After completion of the reaction, the volatile portion was concentrated and dried. 0.37 g of 1,3,3-trimethyl-2-methyleneindoline, 21 ml of n-butanol and 21 ml of benzene were added to the dried material, and the mixture was heated to reflux for 5 hours. The volatile portion was concentrated, and the residue was purified by column chromatography to give 0.24 g of a compound 8 having the following structure.

0069<chemistry id="chem0008" num="0008"><img file="EP0568993A2_D0012.tif" /></chemistry>The melting point and the results of elementary analysis are as follows. Melting point: 260-263 _° C (dec.) <tables id="tabl0005" num="0005"><img file="EP0568993A2_D0013.tif" /></tables>

Reference Example 4

007020 ml of dichloromethane was added to 1.5 g of 3,4-dichloro-3-cyclobuten-1,2-dione, 1.7 g of 1 3,3-trimethyl-2-methyleneindoline was added dropwise under ice-cooling, and after 2 hours, the precipitates were filtered and dried. 35 ml of acetic acid and 50 ml of water were added to the dried material, the mixture was heated on an oil bath at 100 _°C for 1 hour, and the acetic acid and water were distilled off using a rotary evaporator. 100 ml of n-butanol, 5.25 g of 1,3-di-n-hexyl-2-methylimidazo[4,5-b]quinoxalinium tosylate and 1.01 g of triethylamine were subsequently added to the residue, and the mixture was heated to reflux for 3 hours. The volatile portion was concentrated, and the residue was purified by column chromatography to give 3.57 g of a compound 9 having the following structure. <chemistry id="chem0009" num="0009"><img file="EP0568993A2_D0014.tif" /></chemistry>

0071The melting point and the results of elementary analysis are as follows. Melting point: 173.5-174.9 °C <tables id="tabl0006" num="0006"><img file="EP0568993A2_D0015.tif" /></tables>

Reference Example 5

00720.17 g of a compound 11 having the following structure was prepared according to the same manner as that in Reference Example 3 except that 0.72 g of 1,1,2,3-tetramethyl-1 H-benz[e]indolium iodide and 0.28 g of quinoline were added in place of 1,3,3-trimethyl-2-methyleneindoline. <chemistry id="chem0010" num="0010"><img file="EP0568993A2_D0016.tif" /></chemistry>

0073The melting point and the results of elementary analysis are as follows. Melting point: 266-267.6 _° C (dec.) <tables id="tabl0007" num="0007"><img file="EP0568993A2_D0017.tif" /></tables>