DE3607598A1 - LIGHT SENSITIVE COMPOSITION - Google Patents

Description

The invention relates to a photosensitive composition (Preparation or mass), the improved safety light properties, an improved ballpoint pen resistance and has an expanded development latitude and is suitable for a photosensitive positive type lithographic printing plate and a photoresist material.

• / The photosensitive layers for the photosensitive Positive type lithographic printing plates or for a photoresist material usually contain an o-quinonediazide compound as a photosensitive component and an alkali-soluble resin as a component to improve film strength and solubility in alkali.

If several original films are to be printed one after the other in different positions on a photosensitive lithographic printing plate with a photosensitive layer made of such an o-quinonediazide compound, ie by the so-called step-and-repeat printing process, the position of the original can
can be marked on the photosensitive layer to adjust the positions of the original films. In this case, an oily ballpoint pen is usually used

* used as a writing tool for this marking. if however, a solvent for the paint in a ballpoint pen is an organic solvent, in particular a high-boiling glycol type solvent and the like. ° there is a tendency that the light-sensitive Layer of a photosensitive lithographic printing plate attacked by this color and successively is resolved. If the marked points are arranged in a part of the image, a disturbance may be caused, whereby, by developing the plate as such, the photosensitive layer in the marked part in one Image section removed and the marked part on a printed material when it is printed can be reproduced. A light-sensitive one is therefore desirable lithographic printing plate with a photosensitive layer which is susceptible to attack by the Color of a ballpoint pen (hereinafter referred to as "ballpoint pen resistance") is not sensitive is.

20th

It can also be used in photosensitive lithographic Printing plate in which this o-quinonediazide compound is used when printing (duplicating) When working under a white-light fluorescent tube, an optical haze often occurs and when the subsequent development can attack the photosensitive layer in the image portion, whereby a reduction in the layer and in the printing resistance during printing (duplicating) is caused. He wishes is therefore a photosensitive lithographic printing plate having a photosensitive layer with a improved resistance to optical fogging by a white light fluorescent light (hereinafter referred to as "safety light properties").

35

The development of a photosensitive lithographic Printing plate or photoresist material in which

(dem) o-Quinondiaζid compounds are used, is also usually carried out with a developer of an aqueous alkali solution; the development capacity However, a developer changes under changing conditions, with the development capacity May be as a result of exhaustion from treatment or development on a large scale or decrease the deterioration (deterioration) from air oxidation and even during treatment or development the photosensitive layer of the non-image portion in the printing plate or in the photoresist material not fully resolved. Also, on the contrary, there is a tendency that the developing capacity is increased beyond a standard value as a result of excessive supplementation or an increased amount Bath temperature versus atmospheric temperature, so that the image section in the printing plate can be attacked or points can disappear. Therefore, it is particularly a photosensitive lithographic printing plate is desirable that has a wide range of development latitude that has a similar value of development as with the treatment or development with a standard developer results even if either a developer with a reduced developing capacity or a developer having a more increased developing capacity than the standard developer is used will.

Both in photosensitive lithographic printing plates as well as in photoresist materials, novolak resins such as a phenol-formaldehyde resin or a cresol-formaldehyde resin, as an alkali-soluble one Resin together with the photosensitive o-quinonediazide compound used. On the other hand, DE-OS 26 16 992 indicates that the resistance to Alkali developers in photosensitive lithographic Printing plate or the abrasion resistance of the

Coating film in the photosensitive layer is improved can be obtained by using such a novolak resin which has been prepared by polycondensation of phenol substituted by an alkyl group having 1 to 9 carbon atoms with formaldehyde. Also in Japanese Unexamined Patent Application No. 127 553/1970, it is stated that the durability can be improved over alkali developers as noted above by using a copolycondensation novolak resin as a binder that has been produced by condensation of a phenol produced by an alkyl group having 3 to 12 carbon atoms or a phenyl group is substituted; of a phenol, one Phenol derivative which is substituted by methyl, or

15 a mixture thereof; and formaldehyde.

The above two types of resins can improve the safety light properties to some extent Grade improve but they are not easily soluble in alkali and a photosensitive lithographic printing plate, which has the photosensitive layer containing these resins is poor in alkali solubility on when it has been developed and may not be sufficient if sensitivity is reduced be developed when using a developer with a lower development capacity than the standard developer has been developed, for example by exhaustion over a longer development period.

In Japanese Unexamined Patent Application No.

116 218/1979 it is stated that the alkali solubility, Oleophilicity and acid resistance can be improved by using a copolycondensation novolak resin, which has been prepared by the condensation of a tertiary alkyl phenol having 4 to 8 carbon atoms and a phenol or cresol with formaldehyde, either alone or in combination of two or more

1 of them.

The resulting photosensitive lithographic printing plate in which the above-mentioned Novolak resin is used, however, has the disadvantage that the alkali solubility it is not always satisfactory that the development latitude is narrow and that the ballpoint pen durability is low.

10 In Japanese Unexamined Patent Application No.

57 841/1970 it is stated that the alkali solubility, the chemical resistance, the pressure resistance and the color receptivity can be improved with a novolak resin of the copolycondensed resin with phenol, cresol and aldehyde. However, this resin can if the weight average molecular weight (Mw) is not more than 6000, a photosensitive lithographic printing plate having good alkali solubility and high sensitivity, while at the same time exhibiting extremely poor ballpoint pen resistance and has extremely poor safety light properties, and when with a developer having an increased developing capacity as a result of an increased bath temperature and the like.

is treated (developed), a noticeable attack occurs in the image portions. on the other hand If the Mw is more than 600 0, the resistance to this developer becomes increased with an Development capacity beyond the standard value, increased with slightly improved safety light properties, however, the ballpoint pen resistance can hardly be improved along with a lower one Sensitivity or alkali solubility.

In US-PS 4,377,631 it is stated that the sensitivity and resolution in a photoresist Composition can be increased by using a resin obtained by copolycondensation of

■ J- -

m-cresol and p-cresol or o-cresol with formaldehyde has been made as the resin for the photoresist material. However, this resin, if its melting point is less than 110 ^° C., can give a photosensitive lithographic printing plate in which the resin is used having good alkali solubility, but it also gives poor ballpoint pen resistance and poor safety light properties. When the melting point is not below 110 ⁰ C, the Sicherkeitslicht properties can be up to a certain extent, improved, but the alkali solubility may decrease significantly, the non-image portion can not be sufficiently developed by the treatment (development) with an exhausted developer and Pen resistance cannot be improved either.

Japanese Patent Publication 23 570/1979 states that the sensitivity can be improved by using two types of phenol-formaldehyde novolak resins or resole resins that are different Have solubility in an alkali solution with a pH of not more than 12 than a resin contained in a photoresist composition is to be included.

In this case, however, a developer with a higher alkalinity with a pH of up to 13 was used for the photosensitive lithographic printing plate using o-quinonediazide compounds, used. When these two types of resins are applied on a photosensitive lithographic printing plate Therefore, although the sensitivity can be improved, the photosensitive layer or however, the image part in the non-exposed sections can be considerably attacked by an alkali !! developer with poor safety light properties and poor resistance to ballpoint pens.

In Japanese Unexamined Patent Application No. 101 833/1982 and 10 184/1982 is specified that the chemical resistance (chemical resistance), the Alkali solubility and pressure resistance can be improved by applying a condensate a polyhydroxyphenol and benzaldehyde such as a resorcinol-benzaldehyde resin, a pyrogallol-benzaldehyde resin and the like. Or a copolycondensation resin of polyhydroxyphenols and acetone such as pyrogallol-resorcinol-acetone resin and the like, on a photosensitive lithographic printing plate using o-quinonediazide compounds. However, this has the disadvantage of poor safety light properties and a small pen size

15 persistence.

Japanese Unexamined Patent Application No. 86 046/1984 states that alkali development is weak can be carried out by using a condensate of a catechol or hydroquinone derivative with an aldehyde for a photosensitive composition; the safety light properties and however, the ballpoint pen resistance is still poor as in the case of the above-mentioned Japanese

25 see patent application.

Japanese Unexamined Patent Application No. 157 238/1982 states that chemical resistance (Chemical resistance) can be improved with a shortened duration of the firing process by applying a novolak resin with halophenol units on a photosensitive lithographic printing plate using o-quinonediazide compounds will; however, the scope for development is narrow and

35 ballpoint pen resistance is poor.

The main aim of the present invention is therefore to provide a

- / δι to provide photosensitive composition, the improved safety light properties and improved ballpoint pen resistance as well has a wide range of development latitude, 5 without any decrease in sensitivity.

10 15 20 25 30 35

The aim according to the invention can be achieved by a photosensitive composition (preparation or mass), which contains an o-quinonediazide compound and a novolak resin, which is the o-quinonediazide compound is an o-naphthoquinonediazidosulfonic acid ester of a polycondensation resin of pyrogallol with acetone, which has a number average molecular weight

2 3

(Mn) from 5.0 χ 10 to 1.5 χ 10 and a weight average

2 has an average molecular weight (Mw) of 7.0 10 to 4.0 χ 10 and wherein the novolak resin has a weight average molecular weight (Mw ¹ ) of 6.0 χ 10

to 2.0 χ 10 and the ratio between the weight average molecular weight (Mw ¹ ) and the number average molecular weight (Mn ¹ ) of the

15 novolak resin (Mw '/ Mn ¹ ) is 2-14.

In the novolak resin used in the present invention is a resin that was produced by the condensation of a phenol with formaldehyde in the presence of an acid catalyst. Phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, 2,4-xylenol, 2,5-xylenol, carvacrol > Thymol, pyrocatechol, resorcinol, hydroquinone, pyrogallol, phloroglucinol, a p-C ^ -Cn-alkyl-substituted

25th phenol and the like. These phenols can be used alone or in Combination with two or more of them used for condensation with formaldehyde to make the resin will. Among these novolak resins, there can preferably be mentioned the resin produced by

30 Copolycondensation of at least one representative selected from phenol, m-cresol, o-cresol and p-cresol with Formaldehyde; there can be named, for example, a phenol-formaldehyde resin, a m-cresol-formaldehyde resin, an o-cresol-formaldehyde resin, a phenol-p-cresol-

35formaldehyde copolymer resin, a m-cresol-p-cresol-formaldehyde polycondensate resin, an o-cresol-p-cresol-formaldehyde co-polycondensate resin, a phenol-m-cresol-p-cresol-

Formaldehyde copolycondensate resin and a phenol-o-cresolp-cresol-formaldehyde copolycondensate resin. Among the novolak resins listed above, phenolm-cresol-p-cresol-formaldehyde resin can be preferred to be named. 5

A molecular weight (on a polystyrene basis) of the novolak resin of the present invention is a weight average Molecular weight (Mw) of 6.0 10 to 2.0 10, preferably 8.0 10 to 1.5 χ 10. That Ratio between the weight average molecular weight Mw and the number average molecular weight Molecular weight Mn of novolak resin (Mw / Mn). (Hereinafter referred to as "degree of dispersion") is 2 to 14, preferably 3 to 9, particularly preferably 6

15 to 9.

If the invention novolak resin has a weight average molecular weight Mw of less than 6.0 χ 10, it has a significantly .schlechte resistance to the developer k ^e i better safety light properties, a better pen suitability and development capacity as its default values (hereinafter referred to as "overdevelopment properties"). On the other hand, when the weight average molecular weight Mw is more than

4th
2.0 χ 10, the developability with the developer having a decreased developing capacity is inferior to its standard value (hereinafter referred to as "underdevelopment property") with a decreased sensitivity, making development impossible.

In addition, when the degree of dispersion (Mw / Mn) is less than 2, there are inferior underdevelopment properties to be observed, while poor safety light properties can be observed, when Mw / Mn is more than 14, which becomes narrow

Development s game room 'leads.

The molecular weight of the resin is determined by gel permeation chromatography (GPC) method. The number average molecular weight Mn and the Weight average molecular weights Mw are calculated according to a method in which the peak values in the oligomer area equalized or centers of the tip and the foot connected in the peak according to the method of Morio Tsuge et al in The Journal of the Chemical Society of Japan (in Japanese), pages 800 to 805 (1972).

The content of the novolak resin in the photosensitive Compositions is preferably 30 to 95% by weight, in particular 50 to 85% by weight.

The photosensitive composition of the present invention may preferably comprise two or more of the aforementioned novolak resins. It is particularly preferred that the respective molar proportion of phenol and p-cresol fed in, if combined resins are to be produced, is at least 5% of the total resin.

The novolak resin according to the invention can be produced, for example, by the method as described in "Polym. Sei. Polym. Chem.", V \ _, p. 939 (1973) by PW Kopf and ER Wagner.

In the o-quinonediazide compound used in the present invention can be used, it is a compound having at least one o-quinonediazide group, preferably an o-benzoquinonediazide group or an o-naphthoquinonediazide group, and she can be known

gg connections with different structures, e.g. such as those described in "Light-Sensitive Systems" by J. Kosar, John Wiley & Sons, Inc., 1965, pp

339-353, are described in more detail. Esters or amides of various hydroxy compounds or are particularly preferred Amino compounds with o-naphthoquinonediazidosulfonic acid. As preferred hydroxy compounds can be mentioned are condensed resins of a phenol with a carbonyl group-containing compound, in particular those which can be prepared by condensation in the presence of an acid catalyst. As phenol Phenol, resorcinol, cresol, pyrogallol and the like can be mentioned, for example. As those containing carbonyl groups Compound can be mentioned, for example, aldehydes, such as formaldehyde or benzaldehyde, and ketones, like acetone. Particularly preferred are a phenol-formaldehyde resin, a cresol-formaldehyde resin, a pyrogallol-acetone resin and a resorcin-benzaldehyde resin.

As representative examples of the o-quinonediazide compounds can be mentioned an ester of benzoquinone- (1,2) -diazidosulfonic acid or naphthoquinone (1,2) diazidosulfonic acid with a phenol-formaldehyde resin or a cresol-formaldehyde resin; an ester of naphthoquinone (1,2) diazidosulfonic acid with a pyrogallol-acetone resin, as in US Pat. No. 3,635,709 described; a condensate of naphthoquinone- (1,2) -diazido- (2) -5-sulfonic acid with a resorcinol-benzaldehyde resin as in Japanese Unexamined Patent Application No. 1044/1981; an ester compound of naphthoquinone- (1,2) -diazido- (2) -5-sulfonic acid with a resorcinol-pyrogallol-acetone copolycondensate, as described in Japanese Unexamined Patent Application No. 76,346/1980. As another useful one O-quinonediazide compounds can be mentioned an ester or a polyester having terminal hydroxyl groups with the o-naphthoquinone-diazidosulfonic acid, as in the Japanese Unexamined Patent Application No. 11,750/1975; an ester of a homopolymer of p-

Hydroxystyrene or a copolymer thereof with a other copolymerizable monomers with o-naphthoquinonodiazidosulfonic acid and the like

In the photosensitive composition according to the invention, the o-quinonediamide compound can preferably make up 5 to 60% by weight, particularly preferably 10 to 50% by weight, _f .

The o-quinonediazide compound is preferably an o-quinonediazidosulfonic acid ester Polycondensation resin of a polyhydroxyphenol with a ketone or aldehyde which is a number average Molecular weight from 4.0 10 to 2.0 χ 10 and a weight average molecular weight of

2 τ

5.0 10 to 4.0 10. Particularly preferred is the o-naphthoquinonediazidosulfonic acid ester of a polycondensation resin of pyrogallol with acetone, the

a number average molecular weight of

2 3

5.0 χ 10 to 1.5 χ 10 and a weight average

2 3

has a molecular weight of .7.0 10 to 4.0 χ 10.

The o-quinonediazidosulfonic acid ester can be prepared are made by dissolving a condensation resin of the phenol and that containing a carbonyl group Compound in a suitable solvent, e.g. in dioxane and the like, addition of o-quinonediazidosulfonic acid chloride and then adding dropwise an alkali carbonate to an equivalent point to carry out the Esterification.

In this ester compound, the rate of condensation of the o-naphthoquinonediazidosulfonic acid chloride is equal to Hydroxy group in the ester compound (% of an OH group) preferably 20 to 80%, in particular 25 to 70%, particularly preferably 30 to 60%.

The number average molecular weight and the weight average molecular weight of the ester compound will be the same as for that

Novolak resin described determined. 5

The photosensitive composition of the present invention may also contain other additives, if necessary, in addition to the above-mentioned components. As the plasticizer, there can be mentioned various compounds having a low molecular weight, such as e.g. phthalic acid esters, triphenyl phosphates, maleic acid esters; as coating improvers there can be mentioned surface active agents such as e.g. Fluorine-containing surfactants or non-ionic surfactants such as in usually ethyl cellulose polyalkylene ether; and various print-out materials to create a visible one Image when exposed to light.

The copy-out material can contain a compound which can form an acid or a free radical, and an organic dye that is able to restore its original hue by interacting with the to change the former. As the first-mentioned compound, for example, an o-naphthoquinonediazido-4-sulfonic acid halide can be mentioned, as described in Japanese Unexamined Patent Application No. 36 209/1975, a trihalomethyl (2) pyrone or a trihalomethyl triazine, as described in Japanese Unexamined Patent Application No. 36 223/1978, an ester compound of an o-naphthoquinonediazido-4-sulfonic acid chloride with a phenol or an aniline with one electron attractive substituents, as in the unexamined Japanese Patent application No. 6 244/1980 described a halomethyl-vinyl-oxadiol compound and a diazonium salt, as described in Japanese Unexamined Patent Application No. 77,742/1980, and the like.

• λ8 · '"

As an organic dye can be mentioned triphenylmethane, Diphenylmethane, oxazine, xanthene, iminonaphthoquinone, azomethine or anthraquinone paraffin, in the Usually e.g. Victoria Pure Blue-ΒΟΗ (trade name, obtainable from Hodogaya Chemical Co., Ltd.), Oil Blue ß60 3 (trade name, available from Orient Chemical Co., Ltd.), Patent Pure Blue (trade name, available from Sumitomo-Mikuni Chemical Co., Ltd.), crystal violet, brilliant green, ethyl violet, Methyl green, erythrocin B, basic fuchsine, malachite green, Oil Red, m-Cresol-Purple, Rhodamine B, Auramine, 4-p-diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide and the like. ■

A photosensitive resin that can be prepared by the condensation of an oleophilic phenol-formaldehyde resin and a p-substituted phenol-formaldehyde resin with an o-quinonediazidosulfonic acid chloride. will preferably added to improve oleophilicity. The oleosensitizer may preferably be 0.1 to 3% by weight based on the total amount of the photosensitive composition.

A sensitizer can be used to improve sensitivity the photosensitive composition of the present invention be incorporated. A gallic acid derivative can be mentioned, for example, as a sensitizer, as described in Japanese Unexamined Patent Application No. 118 237/1982, 5-membered cyclic Acid anhydrides, such as phthalic anhydride, tetrahydrophthalic anhydride, Hexahydrophthalic anhydride, maleic anhydride, succinic anhydride, pyromellitic acid, Itaconic acid as described in Japanese Unexamined Patent Application No. 80 022/1977, a 6-membered cyclic acid anhydride such as glutaric anhydride or derivatives thereof as described in Japanese Patent Application No. 11,932/1983, and the like.

among them, the cyclic acid anhydrides are preferred and the 6-membered cyclic acid anhydrides are particularly preferred.

The photosensitive composition according to the invention can be dissolved in a suitable solvent that can dissolve all of the above components, them can be applied in the form of a layer to a suitable substrate or carrier and dried are used to make, for example, a photosensitive lithographic printing plate or a Photoresist material.

As a solvent that can be used, there can be mentioned, for example, cellosolves such as methylcellosolve, Methyl cellosolve acetate, E thy Ice Ho solve, ethyl cellosolve acetate and the like, dimethylformamide, dimethyl sulfoxide, Dioxane, acetone, cyclohexanone, trichlorethylene, methyl ethyl ketone and the like. These solvents can be used alone or in combination with two or more of them.

The application in the form of a layer can be done using, known processes, for example by spin coating, wire rod coating, dip coating, Air knife coating, roller coating, blade coating, Curtain coating and the like., Performed will.

As a base or carrier on which a light-sensitive Layer is applied by applying the photosensitive composition according to the invention exemplified are a metal plate such as aluminum, zinc, copper, steel; a metal plate, which is metallized or coated with chromium, zinc, copper, nickel, aluminum, iron and the like; a Paper; a plastic film and a glass plate; a with

a resin coated paper; a paper pasted with a metal foil such as aluminum; a hydrophilic made plastic film and the like, with an aluminum plate being preferred.

If an aluminum plate as a support for a photosensitive lithographic printing plate is used, a surface treatment such as a Graining or roughening, an anodizing treatment and, if necessary, a sealing treatment, can be applied to the plate. These treatments can be carried out using known techniques will.

As a thinning treatment, there can be mentioned, for example mechanical processes or electrolytic etching processes are used. The mechanical methods can include for example ball abrasion, brush abrasion, the Abrasion from liquid honing, buffing and the like. Depending on the composition of the aluminum material used and others, the above methods can be used alone or in combination therewith. Electrolytic etching is preferred.

The electrolytic etching can be carried out in a bath containing an inorganic acid such as phosphoric acid, sulfuric acid, hydrochloric acid, nitric acid and the like . alone or in admixture therewith. After the roughening treatment, if necessary, cleaning treatment with an aqueous solution of an alkali or an acid can be applied to carry out neutralization and washing with water.

The anodizing treatment can be carried out using a solution containing one or more agents from the group consisting of sulfuric acid, chromic acid, oxalic acid, phosphoric acid, malonic acid and the like. Contains as an electrolyte

-M-

and an aluminum plate for electrolysis as a positive electrode. The amount of coating produced by the oxidation on the positive electrode is expediently 1 to 50 mg / dm ² , preferably 10 to 40 mg / dm ² , particularly preferably 25 to ^{40 mg / dm 2} . The amount of coating can be determined, for example, by immersing an aluminum plate in a phosphoric acid-chromic acid solution (prepared by dissolving 35 ml of an 85% phosphoric acid solution and 20 g of chromium (VI) oxide in 1 1 of water) to dissolve the oxidation coating, and Measure the change in weight before and after the dissolution of the plate coating film.

The sealing treatment may include, for example, treatments with boiling water, steam, sodium silicate or aqueous dichromate solution. In addition, an adhesive coating treatment with an aqueous solution of a water-soluble high polymer compound or a metal salt such as zirconium fluoride, ^au -f an aluminum plate pad to be applied.

In addition, there is also a method of improving vacuum contact, which generally involves a printing frame used under vacuum in contacting and printing

• 25 of an original film on a photosensitive lithographic Printing plate, on such a photosensitive lithographic printing plate in which the invention photosensitive composition is used, applicable.

As a method of improving the vacuum contact, there can be mentioned, for example, a method of making a To make the photosensitive layer surface mechanically uneven, a method for distributing solid powder on a photosensitive layer surface, a method of applying a matting layer on a photosensitive layer surface, as in FIG

Japanese Unexamined Patent Application No. 125805/1975 described a method of making solid powder by thermal fusion to a photosensitive layer surface to bind, as in the unexamined Japanese patent application

5 message no. 12 974/1980 described, and the like.

Photosensitive lithographic printing plates or photoresist materials, to which the photosensitive composition of the present invention is applied can be used in the same way as the conventional materials used so far.

For example, the plate can be covered by a transparent positive film with a light source such as e.g.

a positive pressure mercury lamp, a metal halide lamp, a xenon lamp, a tungsten lamp and the like., and then developed with an alkali developer leaving only the unexposed sections on the bare surface and a relief image

20 of the positive-positive type is generated.

An example of an alkali developer can be mentioned an aqueous solution of an alkali metal salt such as sodium hydroxide, Potassium hydroxide, sodium carbonate, potassium carbonate, sodium metasilicate, potassium metasilicate, sodium sec-phosphate or sodium tertiary phosphate. The concentration of the alkali metal salt is preferably 0.1 to 10% by weight. In addition, if necessary, the developer can add anionic surface-active agents, amphoteric surface-active agents or organic solvents, such as alcohols and the like.

The invention is illustrated in more detail by the following examples, without, however, being restricted thereto. 35

example 1

An aluminum plate with a thickness of 0.24 mm was made

degreased in a 5% strength aqueous sodium hydroxide solution and then ^{subjected to electrolytic etching in a 0.5 molar aqueous hydrochloric acid at a temperature of 25 °} C., a current density of 60 A / dm ² and a treatment time of 30 s. After a cleaning treatment with a 5% sodium hydroxide aqueous solution, anodic oxidation treatment was carried out in a sulfuric acid solution. The amount of the coating film by the anodization was 27 mg / dm ² by the method described above. Then, sealing treatment was carried out by immersing in hot water of 90 ^° C.

Subsequently, a photosensitive coating liquid having the composition given below was applied in the form of a layer on the resulting aluminum support by means of a rotary coater and then ^{dried at 100 °} C. for 4 minutes to prepare a photosensitive lithographic printing plate (A).

Composition of the photosensitive coating liquid

1) Ester compound of naphthoquinone- (1,2) -diazido- (2) -5-sulfonic acid chloride with a pyrogallol-acetone resin (number average molecular weight Mn = 1500, weight average molecular weight Mw = 1700, condensation rate 50 mol%) 1.6 g

2) Copolycondensation resin of phenol, m- and p-cresol mixture and formaldehyde (molar ratio phenol: m-cresol: p-cresol = 40: 36: 24, Mw = 9300, degree of dispersion Mw / Mn = 6.2, hereinafter referred to as "novolak resin (I)"

draws) 6.5 g

3) Ester compound of a novolak resin from p-tert-octylphenol and formaldehyde with naphthoquinone- (1,2) -diazido- (2) -5-sulfonic acid chloride (Condensation rate 50 mol%, Mw = 1800) ■ 0.164 g

4) Oil Blue ß60 3 (trade name, available from

Oriental K.K.) 0.08 g

5) ethylene glycol monoethyl ether 68 g

6) ethylene glycol monomethyl ether 33 g

Coating amount after drying about 2 2 mg / dm ²

The molecular weight and the degree of dispersion of the above-mentioned ester compound (1) and the above-mentioned copolycondensation resin (2) were determined by gel permeation chromatography (GPC). The GPC measurement conditions were as follows:

Apparatus: Type 635 from Hitachi Ltd .; Separating column, 3 columns manufactured by Shodex A802, A803 and A804 from Showa Denko K.K., in series with one another - tied together; Temperature: room temperature; Solvent:

25 tetrahydrofuran; Flow rate: 1.5 ml / min.

A calibration curve was produced using polystyrene as the standard.

On the photosensitive lithographic printing plate thus prepared, a step chart for performing sensitivity measurement was placed (Kodek step chart No. 2, manufactured by Eastman Kodak Co., Ltd., a gray scale of 21 steps with a density difference of 0.15) and the resultant The plate was exposed ^{to 8.0 mW / cm 2 for} 70 seconds using a 2 KW metal halide lamp as a light source (Idlefin 2000, manufactured by Iwasaki Electric Co., Ltd.). Then the

Sample developed with a 4% aqueous potassium metasilicate solution for 45 s at 25 ° C, whereby a non-image Area was completely removed to form a lithographic printing plate. The sensitivity measurement with the gray scale using the step table showed that 4 1/2 steps were fully developed or clear.

Then a developer was prepared which had a more dilute alkali concentration than the standard, a 4% aqueous Potassium metasilicate solution, and a developer that had a higher Alkali concentration as the standard to examine the development latitude. Under use the sample exposed for 70 seconds as described above underwent development with the developer with a reduced development capacity (underdevelopment) as well as development with the developer with excessive development capacity (overdevelopment) examined. When examining the underdevelopment development was carried out with a 2.1% strength and 1.9% strength aqueous potassium metasilicate solution for 45 seconds carried out at 25 ° C to assess the solubility of the non-image areas. The better the photosensitive The better the layer could be dissolved in the diluted developer in the non-image areas

25 underdevelopment.

On the other hand, when investigating overdevelopment, development was carried out with a 6% aqueous potassium metasilicate solution for 60 seconds at 25 ^° C. and 90 seconds at 25 ^° C. with a 7.2% aqueous potassium metasilicate solution; the solid step number (ie the minimum step number at which a photosensitive layer remained completely in the gray scale of the step table) was determined, and then the difference between

35 of this stage number and the solid stage number one

Standard development (for 4 5 s at 25 ^° C. with a 4% strength aqueous potassium metasilicate solution) was determined. The lower

this solid-stage number difference was, and the closer it was The standard development, the better the overdevelopment. Under a good development margin is to be understood that both the underdevelopment as

5 also the overdevelopment were good.

In order to examine the ballpoint pen resistance, three types of ballpoint pens, that is, using the ballpoint pen / JL] (ZEBRA N5100 Black, manufactured by Zebra KK ) JjLTj (GOLF blue manufactured by Tombow Enpitsu KK) and ΖΪΙΙ / (Pilot BS blue manufactured by Pilot Pen Co., Ltd.) _; Lines drawn. After standing for 10 minutes, the standard development was carried out without exposure. The ballpoint pen resistance was assessed by determining the attacked planes in the light-sensitive layer after writing with the

20 hands with three evaluation levels.

To examine the safety light properties, the photosensitive lithographic printing plate (A) before exposure and development for 10 minutes with a fluorescent tube (fluorescent lamp) of white color exposed at 310 lux to produce an optical fog and then it became the standard development subject. The film reduction rate in the photosensitive Layer was determined. The film reduction rate is to be understood as a value which indicates the decrease in film thickness, the film thickness being the photosensitive Layer in the photosensitive lithographic printing plate developed without optical fog compared becomes with the thickness of the optical haze developed layer. The lower this value is, around therefore the safety light properties are better.

-24-

In addition, to examine the decrease in printing resistance with the optical fog, the photosensitive lithographic printing plate (A) exposed in contact with a positive original film as described above, and, as mentioned above, an optical fog was made using a fluorescent tube (fluorescent lamp) with white Creates light.

The subsequent standard development was carried out to produce a lithographic printing plate / Ϊ /. On the other hand, another lithographic printing plate [TlJ was prepared using the same treatment method as described above without using any optical fog. The two lithographic printing plates flj and / Il7 were set together in an offset printing device (HAMADASTAR 900CDX, manufactured by Hamada Printing Press Manufacture Company Co., Ltd.) to perform printing (duplicating). The end point of printing resistance was determined as the point at which a solid (solid) part peeled off in the image portion and printing (duplicating) could no longer be performed.

The results of the determination of the sensitivity, des Development latitude, the ballpoint pen resistance and the safety light properties are summarized in Table I below.

30 Comparative Example 1

A photosensitive lithographic printing plate (B) was prepared using the same procedures as described in Example 1 except that the novolak resin [XXJ described below was used in place of the novolak resin JjJ in the photosensitive coating liquid.

1 novolak resin / Ϊΐ7

Copolycondensation resin from phenol and m- and p-cresol mixtures with formaldehyde (molar ratio phenol: m-cresol: p-cresol = 40: '36: .24, Mw = 1500, Mw / Mn = 6.2)

The novolak resins £ 1] and fllj were the same in terms of composition and degree of dispersion and only different in terms of Mw.
10

Coating weight after drying approx. 200 mg / dm ²

The photosensitive lithographic printing plate (B) became examined in the same way as in Example 1 to determine the sensitivity, the development bearing space, the ballpoint pen resistance and the safety light properties. The results are given in Table I.

20 Comparative Example 2

A photosensitive lithographic printing plate (C) was prepared by the same procedures as in Example 1 except that the novolak resin EIII described below was used in place of the novolak resin ΓΧΙ in the photosensitive coating liquid .

Novolak resin ΖΪΙΙ7

Copolycondensation resin of phenol and m- and p-cresol mixtures with formaldehyde (molar ratio phenol: m-cresol: p-cresol = 40: 36: 24, M _w = 9320, Mw / Mn = 15)

The novolak resins / i / and / ill / were compositionally and weight average molecular weight about the same but different in terms of

1 the degree of dispersion

Coating weight after drying ...... about 22 mg / dm ²

The photosensitive lithographic printing plate (C) was examined in the same manner as in Example 1 to determine the sensitivity, development latitude, ballpoint pen resistance, and Safety light properties. The results are given in Table I.

Comparative example 3

A photosensitive lithographic printing plate (D) was prepared by the same procedures as in Example 1 except that the following two novolak resins (total amount 6.5 g) were used in place of the novolak resin JHJ in the photosensitive coating liquid.
20th

1) Copolycondensation resin of phenol, p-tert-butylphenol and formaldehyde (molar ratio phenol: p-tert-butylphenol = 50:50, prepared on the same way as in Example 1 of the unexamined

25 Japanese Patent Application No. 127 553/1980

described, Mw = 5000, Mw / Mn = 4.5) 3.25 g

2) phenol formaldehyde novolak resin (Mw = 21,000,

Mw / Mn = 17) 3.25 g

Coating weight after drying ... about 22 mg / dm ²

The photosensitive lithographic printing plate (D) was examined in the same manner as in Example 1 to determine the sensitivity, development latitude, ballpoint pen resistance, and Safety light properties. The results are in

1 of Table I. Comparative example 4

A photosensitive lithographic printing plate (E) was prepared by the same procedure as in Example 1 except that the novolak resin shown below was used in place of the novolak resin JXJ in the photosensitive coating liquid. 10

Novolak resin

Copolycondensation resin of m-cresol and p-cresol with Formaldehyde (oil ratio m-cresol: p-cresol = 50:50, prepared in the same way as indicated in Synthesis Example 1 of DE-OS 2 6 16 992, Mw = 1800, Mw / Mn = 1.4)

Coating weight after drying about 22 mg / dm ²

The photosensitive lithographic printing plate (E) became examined in the same manner as in Example 1 to determine the sensitivity, the development latitude, the ballpoint pen resistance and the safety light properties. The results are given in Table I.

Comparative example 5

Following the same procedure as in Example 1, a photosensitive lithographic printing plate (F) was prepared, except that was used instead of the novolak resin [ij in the light-sensitive coating liquid described below, the novolak resin.

1 novolak resin

Copolycondensation resin of phenol and p-tert-butylphenol with formaldehyde (weight ratio phenol: ptert-butylphenol = 60:40 as in Synthesis Example 1 of Japanese Unexamined Patent Application No. 116 218/1979 described, Mw = 4500, Mw / Mn = 4.0)

Coating weight after drying about 22 mg / dm ²

The photosensitive lithographic printing plate (F) was examined in the same manner as in Example 1 to determine the sensitivity, development latitude, ballpoint pen resistance, and Safety light properties. The results are given in Table I.

Table I.

Enpf ind, Kuqelschrei, safety light features

sSen) £ ^{0% 1-2% V5;} (%)

25 ° C / 60 "25 ° C / 90" 2.1% 1.9% I II III

example 1 4th 1/2 2.0 3 .0 O O A. A. A. 8th 15th Comparison
example 1 5 5.0 O O C. B. C. 75 90 Comparison
example 2 4th 1/2 3.0 5 .0 O Δ C. B. B. 50 75 Comparison
example 3 3 1.0 2 .5 X χ B. A. B. 10 20th Comparison
example 4 3 1/2 1.5 2 .5 Δ X B. A. B. 13th 25th Comparison
example 5 2 1/2 1.0 2 .0 X X B. A. B. 10 18 -

In Table I above, the letter "A" indicates a minor attack in the image portion, the letter "B" represents little attack and a little exposed roughened surface in the substrate below of the photosensitive layer and the letter "C" shows one marked attack and one complete exposed roughened surface in the support below the photosensitive layer.

In the underdevelopment column, the open circle symbol (Q) shows complete dissolution and removal of the light-sensitive layer in the non-image area, the open triangle symbol (Δ) shows the partial right of the photosensitive layer and the X symbol (X) shows a low resolution of the photosensitive layer Shift on.

In the overdevelopment column, the value given gives the difference in the number of solid levels with the Standard development on and the symbol (-) stands for a clearly damaged part of the image, which is too bad Indicates overdevelopment, so that the number of the solid stage could hardly be determined.

The results of the above example and the above comparative examples show the following: when Example 1 is compared with Comparative Example 1, the Overdevelopment, the pen resistance and the safety light properties significantly worse in the novolak resins used with the same composition if the weight average molecular weight Mw is not more than 6000 even if the degree of dispersion is not more than 14 in both Resins. The comparison between Example 1 and Comparative Example 2 shows that the overdevelopment and the safety light properties are greatly deteriorated when the two novolak resins used are the same

Composition have a degree of dispersion of not less than 14 even with the same weight average Molecular weight not less than 6000.

The performance of a photosensitive lithographic Printing plate should not be based on any one property alone, but generally on the basis of several properties be assessed. The above photosensitive lithographic printing plates (B) to (F) have one extraordinary disadvantage with regard to at least one of the properties in Table I: the comparative example 1 shows poor underdevelopment, poor ballpoint pen resistance and poor safety light properties, Comparative Example 2 shows poor safety light properties and poor Overdevelopment and Comparative Examples 3 to 5 show lower sensitivity and poor Underdevelopment.

The photosensitive lithographic of the present invention On the other hand, printing plate (A) of Example 1 above did not show any serious drawbacks, that is, it has superior over and under development, a wide exposure latitude and generally uniform one superior sensitivity, pen resistance and safety light properties.

Example 2

Using the same procedures as in Example 1, a photosensitive lithographic printing plate was prepared (G), but this time a photosensitive coating liquid of the one given below Composition in the form of a coating applied to the aluminum support prepared in Example 1 and was dried.

-32-

Composition of the photosensitive coating liquid

1) Ester compound of naphthoquinone- (1,2) -diazido- (2) -5-sulfonic acid chloride with m-cresol-formaldehyde novolak resin (condensation rate = 25 mol%, Mn = 1200,

Mw = 1800) 2.9 g

2) Copolycondensation resin of o-, m- and p-cresol mixtures and formaldehyde (weight ratio m-

Cresol: p-cresol: o-cresol = 70: 20: 10, Mw =

92 00, Mw / Mn = 8.0, melting point = 83 ⁰ C). . . "5.3 g

3) Victoria Pure Blue-ΒΟΗ (trade name, manufactured

from Hodogaya Chemicals Co., Ltd.) 0.08 g

4) Ethylene glycol monoethyl ether 100 g

Coating weight after drying about 22 mg / dm ²

The molecular weight and the degree of dispersion of the ester compound (1) and the copolycondensation resin (2) became determined in the same manner as in Example 1. The melting point (F.) was measured by means of a melting point measuring apparatus Buchi 510 manufactured by BUCHI Co., Ltd. was measured.

The photosensitive lithographic sheet thus obtained Printing plate (G) was examined in the same manner as in Example 1 to determine the sensitivity. latitude, pen resistance and safety light properties. The results are summarized in Table II below.

1 comparative example 6

By the same procedures as in Example 1, a photosensitive lithographic printing plate (H) was prepared. this time, however, instead of the copolycondensation resin (2) in Example 2, that described below Novolak resin was used.

Novolak resin

Copolycondensation resin of o-, m- and p-cresol mixtures with formaldehyde (weight ratio m-cresol: p-cresol: o-cresol = 70: 20: 10, Mw = 25,000, Mw / Mn = 8.0, melting point = 143 ⁰ C, synthesized in the same manner as indicated in Example 2 of U.S. Patent 4,377,631) 5.3 g

Coating weight after drying ...... about 22 mg / dm ²

The photosensitive lithographic printing plate (H) was examined in the same manner as in Example 1 to determine the sensitivity, the development latitude, the ballpoint pen resistance and the safety light properties. The results are in the

25 Table II.

Comparative example 7

By the same procedures as in Example 1, a photosensitive lithographic printing plate (I) was prepared. this time, instead of the copolycondensation resin (2) in Example 2, the following novolak resin was used.

35 novolak resin

Copolycondensation resin of o-, m- and p-cresol mixtures with formaldehyde (weight ratio m-cresol: p-cresol:

1 o-cresol = 70: 20: 10, Mw = 25,000, Mw / Mn = 15,

Melting point = 100 ^° C.) 5.3 g

Coating weight after drying about 22 mg / dm ²

The photosensitive lithographic printing plate (I) was examined in the same manner as in Example 1 to determine the sensitivity, development latitude, ballpoint pen resistance, and Safety light properties.

The results of Example 2 and Comparative Examples 6 and 7 are also given in Table II.

Table II

Sensitive- developmental leeway

ability (number

the clear _fiu,. , _Ί

Stages) development

Ballpoint security light properties

Underdeveloped "J JJJ ^ Fxlmreduk- Druckbestänlung "rate of downtime reduction

4th 6.0%
25 C / 60 " 7.2%
25 C / 90 " 2.1% 1.9% I. II III (%) txonsrare Example 2 2 1/2 1.5 2.5 O O A. A. A. 5 10 Comparison
example 6 3 1.0 1.5 X X B. Ά B. 10 20th Comparison
example 7 2.5 3.5 Δ Δ B. B. B. 30th 50

ι co Sen

In Table II, the symbols and values given have the same meanings as in relation to Table I. specified.

As a comparison of Example 2 with Comparative Example 6 shows, the underdevelopment and sensitivity were significantly worse even with novolak resins the same composition and the same degree of dispersion if the weight-average molecular weight

4 10 weight was not less than 2.0 χ 10.

A comparison of example '2 with the comparative example 7 also shows that both overdevelopment and underdevelopment were slightly worse, so that a narrow development leeway was achieved, with poorer ones Safety light properties, even with novolak resins of the same composition when the degree of dispersion is not more than 14 and the weight average

4 molecular weight (Mw) were not less than 2.0 10.

Example 3

By the same procedures as in Example 1, a photosensitive lithographic printing plate (J) was prepared. this time using the following novolak resin instead of the copolycondensation resin (2) of Example 2 became.

Novolak resin 30

Copolycondensation resin of m- and p-cresol mixtures with Formaldehyde (molar ratio m-cresol = p-cresol = 90: 10, MW = 6500, Mw / Mn = 4.5) 5.3 g

Coating weight after drying ... about 22 mg / dm ²

The photosensitive lithographic printing plate (J) became examined in the same way as in Example 1 for

Determination of the sensitivity, the development latitude, the ballpoint pen resistance and the safety light properties .

As a result, it was found that the sensitivity was so high that four grades of gray scale of a grading table were clear. Regarding overdevelopment, the difference in the number of solid stages was 2.0 under the condition of developing with a 6.0% aqueous potassium metasilicate solution at 25 ^° C. for 60 seconds, while the difference in the number of solid Under the condition of development with a 7.2% strength aqueous potassium metasilicate solution at -25 ° C. for 90 seconds, the underdevelopment was found to have a solubility of the open circle symbol (O) or the open triangle symbol (/ \) as determined in Table I under the condition of development with a 2.1% or 1.9% aqueous solution of potassium metasilicate at 25 ^° C. for 45 s ) B and for the ballpoint pens (II) and (III) A. The safety light properties were 12% for the film reduction rate and 20% for the print resistance reduction rate.

The photosensitive lithographic printing plate (J) showed generally favorable performance in terms of sensitivity, development latitude, ballpoint pen resistance and safety light properties on as well as the photosensitive lithographic printing plates

30 (A) and (G).

From the above, it can be seen that the inventive photosensitive composition containing the novolak resin with a specific weight average Molecular weight Mw and a specific degree of dispersion Mw / Mn, an improved resistance

versus an oily ballpoint pen in which an organic solvent is used as the solvent for the paint becomes, and improved safety light properties without decrease in sensitivity, excellent Properties in under- and overdevelopment and one has broad scope for development.

10 15th

25th 30th 35

Claims (11)

T 55 390 Applicant: Konishiroku Photo Industry Co., Ltd. 26-2, Nishi-shinjuku 1-chome, Shinjuku-ku Tokyo / Japan Claims 1- Photosensitive composition, g e k e η η draws by an o-quinonediazide compound and a novolak resin, which is the o-quinonediazide compound around an o-naphthoquinone-diazidosulfonic acid ester of a polycondensation resin from ·. · Pyrogallol with acetone, which is a numerical 2 average molecular weight (Mn) of 5.0 χ 10 to 1.5 χ 10 and a weight average molecular weight 2 3 weight (Mw) of 7.0 χ 10 to 4.0 χ 10, and wherein the Novalak resin has a weight average molecular weight (Mw ¹ ) of 6.0 χ 10 to 2.0 χ 10 and the ratio of weight average molecular weight (Mw ¹ ) to number average molecular weight (Mn ¹ ) of novolak resin (Mw ¹ / Mn ¹ ) is 2-14. 2. Photosensitive composition according to claim 1, characterized in that the novolak resin is a resin made by Copolycondensation of at least one member from the group consisting of phenol, m-cresol, o-cresol and p-cresol, with formaldehyde. 3. Photosensitive composition according to claim 2, characterized in that it is the novolak resin is a resin that was produced by copolycondensation of phenol, m-cresol and p-cresol with Formaldehyde. 4. Photosensitive composition according to one of claims 1 to 3, characterized in that the weight average molecular weight of the novolak resin (Mw ¹ ) is 8.0 χ 10 ³ to 1.5 χ 10 ⁴ ! 5. Photosensitive composition according to any one of claims 1 to 4, characterized in that the ratio of weight average molecular weight (Mw ¹ ) to number average molecular weight (Mn ') of the novolak resin (Mw' / Mn ¹ ) is 3 to 9. 6. Photosensitive composition according to any one of claims 1 to 5, characterized in that the ratio of weight average molecular weight (Mw ¹ ) to number average molecular weight (Mn ¹ ) of the novolak resin (Mw '/ Mn ¹ ) is 6 to 9. 7. Photosensitive composition according to any one of claims 1 to 6, characterized in that the The content of the novolak resin is 30 to 95% by weight. 8. Photosensitive composition according to claim 7, characterized in that the novolak resin content is 50 to 85% by weight. 9. Photosensitive composition according to any one of claims 1 to 8, characterized in that it is the o-quinonediazide compound is an o-naphthoquinonediazidosulfonic acid ester a polycondensation resin of pyrogallol with acetone and an o-naphthoquinonediazidosulfonic acid chloride acts. 10. Photosensitive composition according to claim 9, characterized in that the rate of condensation of the o-naphthoquinonediazidosulfonic acid chloride to the OH group in the o-naphthoquinonediazidosulfonic acid ester is 20 to 80%. 1 11. Photosensitive composition according to claim 10, characterized in that the condensation rate is up to 70%.