JPS62288849A - Original plate for waterless lithographic printing plate - Google Patents

Abstract

PURPOSE:To maintain scratching strength which remains high for a long period of time by using silicone rubber obtd. by contg. a specific compd. as an essential component for a silicone rubber layer. CONSTITUTION:The silicone rubber layer of an original plate for waterless lithographic printing constituted by laminating a substrate, photosensitive layer and silicone rubber layer in this order contains the silicone rubber obtd. by contg. at least one kind of the compd. among the following compds. and curing the same as the essential component: The silane or siloxane in which a hydrocarbon group having an urethane bond and hydrolyzable group are directly bonded to a silicon atom, silane or siloxane in which a hydrocarbon group having a urea bond and hydrolyzable group are directly bonded to a silicon atom or silane or siloxane in which the monovalent org. group expressed by formula and hydrolyzable group or hydroxyl group are directly bonded to a silicon atom. The silicone rubber layer to be used consists essentially of the silicone rubber obtd. by crosslinking the organopolysiloxane having the repeating unit expressed by formula, where n is >=2 integer, R<6>, R<7> are a hydrogen atom, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to an original plate for waterless planographic printing that can be printed without using dampening water.

[Prior Art 1] Many waterless lithographic plates have been proposed that use a silicone rubber layer as an ink repellent layer and are capable of printing without using dampening water.

Among these, waterless planographic plates, which are composed of a substrate, a photosensitive layer, and a silicone rubber layer in this order, are characterized by ease of plate making and good ink repellency. In particular, a waterless lithographic printing Kawahara plate containing a quinonediazide compound in the photosensitive layer, as shown in Jiko No. 55-110249, is useful as a negative-type plate for normal exposure.

However, in such printing plates, the adhesive strength between the photosensitive layer and the silicone rubber layer is less than 1q, and as a result, there are problems such as easy scratches in non-image areas and poor image reproducibility of halftone dots. It was causing problems.

[Problems to be Solved by the Invention] The following have been proposed to supplement the adhesive strength between the photosensitive layer and the silicone rubber layer. Japanese Unexamined Patent Publication No. 1983
-158169 proposes providing an adhesive layer between the photosensitive layer and the silicone rubber layer. In addition, JP-A-55-110249 and JP-A-49-73202 propose adding a silane coupling agent to the silicone rubber layer, but other than (aminoalkyl) (alkoxy) silane, it is not effective as a raw material. There is nothing. Further, Japanese Patent Laid-Open No. 58-60744 proposes adding a titanium compound to a silicone rubber layer. Additions of these (aminoalkyl)(alkoxy)silanes, organic titanium compounds, etc. have high adhesive strength initially after the original plate is manufactured, but the physical properties of the rubber deteriorate over time, and when operations such as plate ink cleaning are performed, silicone The problem was that the rubber layer was easily damaged.

The present invention was devised in view of the various shortcomings of the prior art, and the purpose of the present invention is to obtain a waterless lithographic printing original plate that maintains high scratch strength over time based on a study of adhesion imparting performance. .

[Means for Solving the Problems] The present invention provides a waterless lithographic printing original plate that is constructed by laminating a substrate, a photosensitive layer, and a silicone rubber layer in this order, in which the silicone rubber layer has the following (I>, (II) >, (■) Contains at least one type of compound and cures to 1q silicone rubber as a main component. This relates to adhesion agents.

(I> Hydrocarbon group having a urethane bond, J: Silane or siloxane with a hydrolyzable group directly bonded to a silicon atom, (II) Hydrocarbon group having a urea bond and a hydrolyzable group directly bonded to a silicon atom (III) A silane or siloxane in which a monovalent organic group represented by the general formula (A) and a hydrolyzable group or a hydroxyl group are directly bonded to a silicon atom, a silane or siloxane having the formula (A> (where R1, R2 , R3, R4 are hydrogen atoms or 1
R5 is a divalent hydrocarbon group).

The substrate in the present invention is not particularly limited, and any substrate used in known waterless lithographic printing original plates may be used.

Examples include metal plates such as aluminum, iron, and zinc, paid polymer films such as polyester, polyamide, and polyolefin, and composites thereof. It is also possible to further coat these substrates for purposes such as preventing halation.

As the photosensitive layer of the present invention, various photosensitive layers used in waterless lithographic printing original plates, which are formed by laminating a known substrate, a photosensitive layer, and a silicone rubber layer in this order, can be used. Particularly effective components in the photosensitive layer include (1) those having a group that can be converted into two groups by exposure (for example, a cinnamylidene group) as shown in JP-A No. 60-21050; (2) JP-B No. 5B-23150; (3) Those having a quinonediazide group as shown in JP-A No. 55-59466. Among the most useful are the quinonediazide compounds.

As the quinonediazide compound, for example, normally positive PS
The quinonediazides used in the printing plates, Waibon printing plates, Fu, TL-Regime 1~, etc. are not used. Specific compounds include, for example, esters of benzoquinone-1,2-diazide-4- or 5-sulfonic acid and polyhydroxyphenyl, naphthoquinone-1,2-diazide-4- or -
Esters of 5-sulfonic acid and pyrogallol acetone resin, def 1-quinone-1,2-diazide-4- or -
Esters of 5-sulfonic acid and phenol formaldehyde novolac resin, esters of naphthoquinone-1,2-diazide-4- or -5-sulfonic acid and polyhydroxystyrene, such as those proposed in Mochima 1980-80046. Examples include reaction products of quinonediazide compounds and polyfunctional compounds.

Particularly preferable quinonediazide compounds in the present invention are partially esterified products of naphthoquinonediazide-5-sulfonic acid and phenol formaldehyde novolak resin or polyhydroxystyrene. It is also possible to add various components to the photosensitive layer for the purpose of improving coating film formation, improving adhesion to a substrate, coloring, etc., within a range that does not impair the effects of the present invention.

The thickness of the photosensitive layer is selected to be 0.1 to 100 microns, more preferably 0.5 to 30 microns.

If it is too thin, pinholes will easily form in the photosensitive layer.
On the other hand, if it is too thick, it is economically disadvantageous, so the above range is preferable.

The silicone rubber layer used in the present invention is mainly composed of silicone rubber obtained by crosslinking organopolysiloxane having repeating units as shown in the following formula.

Here, n is an integer of 2 or more, and R6 and R7 are hydrogen atoms or unsubstituted or substituted (e.g., halogen atoms, cyano groups, amino groups) hydrocarbon groups having 1 to 10 carbon atoms; Desirably, it is an alkyl group, an alkenyl group, or a phenyl group, and it is particularly desirable that 60% or more of the sum of R6 and R7 is a methyl group.

As a structure of the present invention, the crosslinking method for producing a silicone rubber from an organopolysiloxane is as follows. A condensation reaction is carried out with a silane or siloxane in which two or more (more preferably three or more) groups (such as silane, ketoximate group, amino group, aminooxy group, or halogen atom) are bonded to a silicon atom. In this case, it is possible to crosslink by making the number of silanol groups and the number of hydrolyzable groups in the organopolysiloxane almost the same, or by setting the number of hydrolyzable groups in excess and performing hydrolytic condensation to effect crosslinking. .

The desirable composition of this silicone rubber before curing is as follows: (a) Organopolysiloxane having an average of 1.5 or more silanol groups, 100% by mass) A crosslinking agent having a hydrolyzable group: 0.5% ~20 hand ω parts, and it is also possible to add a coating film solvent, a reinforcing filler, a curing catalyst, and a known adhesive agent.

Compound (I) having adhesion imparting performance, which is a feature of the present invention,
A detailed explanation of (II> and (DI)) is provided below.These hydrocarbon groups having a urethane bond, hydrocarbon groups having a urea bond, and organic groups represented by the formula (A) are used as a waterless lithographic printing original plate. This is a new product that has the adhesive performance of

(i> Hydrocarbon group having a urethane bond, silane or siloxane in which a hydrolyzable group is bonded to a silicon atom.

Here, the hydrolyzable group is exemplified by the above-mentioned groups, but from the viewpoint of ease of synthesis, an alkoxy group of a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms is preferable, and more preferably an alkoxy group having 1 to 10 carbon atoms. 6, an alkyloxy group or an alkenyloxy group.

Also, the hydrocarbon group that forms the urethane bond is
General formula (in the formula, R8 is a substituted or unsubstituted 1 having 1 to 40 carbon atoms)
a valent hydrocarbon group, which may contain heteroatoms such as O, N, S, etc. In the formula, R9 is a monovalent group represented by a substituted or unsubstituted divalent hydrocarbon group having 2 to 10 carbon atoms, preferably a substituted or unsubstituted alkylene group having 2 to 5 carbon atoms, or a monovalent group represented by the general formula (formula R10 and R11 are defined in the same way as R9, and R is a divalent hydrocarbon group, preferably a substituted or non-replaceable hydrocarbon group having 2 to 40 carbon atoms, provided that heterogeneous groups such as 0, A divalent base (which may contain an atom) is exemplified. Among these groups, (B
), (E) are effective.

The general structural formula of compound (I) is as follows:
or their hydrolyzed condensates are shown in 1911.

(In the formula, R13 is a monovalent hydrocarbon group having a urethane bond, R18 is a divalent hydrocarbon group having a urethane bond,
R14 and R16 are hydrogen atoms or substituted or unsubstituted monovalent hydrocarbon groups having 1 to 10 carbon atoms, R15 and R17
is a hydrolyzable group defined as above, 0 is 0 or more and 3
The following integers, m and n are integers from 1 to 3, 2≦m+n
≦4).

Specific examples of such compounds include the following:
Or its hydrolyzed condensate can be mentioned.

In the formula, n is an integer of 2 or more, meaning that it has a repeating structure.

H U+-+ :2 days +3' +3 S)3, :2)-15>3, ii (0C2Hs)3, Si(OC2H5)3, An example of their synthesis is (isocyanatoalkyl) (alkoxy)silane and an alcohol compound or a phenol compound under conditions such that the number of isocyanate groups and hydroxyl groups is the same to form a urethane bond.

(II) A hydrocarbon group having a urea bond, and a silane or siloxane in which a hydrolyzable group is directly bonded to a silicon atom Examples of the hydrolyzable group include those mentioned above, but preferred are An alkoxy group of a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, more preferably an alkyloxy group or alkenyloxy group having 1 to 6 carbon atoms.

In addition, the hydrocarbon group having a urea bond mentioned here is as follows: divalent hydrocarbon group, provided that R21, R38
is 0. It may also contain heteroatoms such as N and S. R
22 is a substituted or unsubstituted divalent hydrocarbon group having 2 to 10 carbon atoms, preferably a substituted or unsubstituted divalent hydrocarbon group having 2 to 5 carbon atoms. R23 and R24 are a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 40 carbon atoms, and it is preferable that at least one of R23 and R24 is a hydrogen atom. or the general formula (wherein R25 and R26 are defined in the same manner as R22 above.
Defined similarly to R24. It is preferable that at least one of R27 and R28 is a hydrogen atom, and it is preferable that at least one of R29 and R30 is a hydrogen atom. R31 is a divalent hydrocarbon group, preferably a substituted or unsubstituted hydrocarbon group having 2 to 40 carbon atoms, but may contain a heteroatom such as 0, N, or S. The following groups are exemplified.

The general structural formula of compound (II>) is exemplified by the following or a hydrolyzed condensate thereof.

(In the formula, R32 is a monovalent hydrocarbon group having a urea bond,
R37 is a divalent hydrocarbon group having a urea bond, R34,
R36 is a hydrolyzable group, R33 and R35 are a hydrogen atom or a substituted or unsubstituted group having 1 to 10 carbon atoms≦m+n≦4
).

Specific examples of such compounds include the following:
Or its hydrolyzed condensate can be mentioned.

Hυ H OCH3)s Si (OC2H5) 3 (Shidari)3≧1+Sil″12s3N-
He-shi-I I\ / II HOCIIkoC1120 (CHz+3Si (OCI(+>3QCH3)3 +C)lko+33i (OCt(s)3 0Hgo)3 (CH2> 33i (OCH3> 3Cth)3 N-4Cll -3si(OCH+)3 1'' (in the formula, n is an integer of 2 or more and means having a repeating structure) As a method for synthesizing these compounds, for example, (- or secondary aminoalkyl) ( It can be obtained by reacting an (isocyanatoalkyl)(alkoxy)silane with a monovalent or divalent isocyanate compound, or by reacting an (isocyanatoalkyl)(alkoxy)silane with a compound having one or two -grade or secondary amine groups. It will be done.

Next, the compound (■), that is, represented by the general formula (A)]
A detailed explanation will be given of silanes or siloxanes in which a valent organic group and a hydrolyzable group or a hydroxyl group are directly bonded to a silicon atom.

(In the formula (A>, R1, R2, R3, and R4 are hydrogen atoms or monovalent hydrocarbon groups, but preferably have 1 to 1 carbon atoms.
10 hydrocarbon groups, most preferably methyl, ethyl, propyl, and phenyl groups.

R5 is a divalent hydrocarbon group, preferably having 2 carbon atoms.
~10 hydrocarbon groups, more preferably ethylene groups,
These are trimethylene group and tetramethylene group.

The following structures are exemplified as general structural formulas of compound (I[I).

General formula (wherein R39 is an organic group having the structure (A>), R41 is the same hydrolyzable group as above, and is preferably a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms for ease of synthesis. R is an alkoxy group, more preferably an alkyloxy group or alkenyloxy group having 1 to 6 carbon atoms.
40 is a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, m is an integer of 1 to 3, and n is 1
A silane or a hydrolyzed condensate thereof represented by an integer of 3 or less, 2≦m+n≦4.

In addition, the general formula (wherein R39 is an organic group having the @ structure of (A), R42
, R44, R45, R46 are hydrogen atoms or have 1 carbon number
-10 substituted or unsubstituted monovalent hydrocarbon groups, more preferably a methyl group, ethyl group, vinyl group, propyl group, halogenated propyl group, phenyl group, or hydrogen atom. R43 is a hydroxyl group or a hydrolyzable group. R47, R4
8, R49, R50, R51, and R52 are monovalent groups arbitrarily selected from organic groups having the structure of (A) or the same groups as defined for R42 and R43. Each structural unit may be random or block, and l, m, and n are integers of 0 or more.

However, the structure must have one or more hydroxyl groups or hydrolyzable groups, and one organic group having the structure (A) must be present.
(It is necessary to have at least 1)

Specific examples of the compound (III) include the following.

R39-3i (0C3H? > 3.

R39-3i (0C3Hs) 3.

(R39± 2 si+oc t13>2゜(R39
±2Si+0C2t~I5>3゜R39-Si+OCR
3) 2CR2CR2CR2Cα.

R39-Si+OC2Hs) 2 number CR2CR2C1-12CD,.

(In the formula, R39 is a fumama group having the structure of (A>, h, m
, n is an integer of 1 or more, and the structure may be random or block. Specific examples of R39, that is, an organic group having the structure (A>), are as follows: Among these, the group bonding to the nitrogen atom is methyl. It is preferable that it is a base or an ethyl group.

Compound (III) can be synthesized by a dehydrochlorination reaction between a compound in which a halogenated alkyl group is bonded to a silicon atom and a guanidine compound in which an active hydrogen is bonded to a nitrogen atom. An example of this is the reaction shown below.

The following method is exemplified for incorporating the above compounds into silicone rubber.

(1) After coating the photosensitive layer on the substrate, a composition containing at least one of the compounds (I>, (II), and (III), which is a feature of the present invention, is coated, and then uncured silicone rubber is coated. A method of applying a composition and curing it to form a silicone rubber layer.

(2) After coating the photosensitive layer on the substrate, an uncured silicone rubber composition containing at least one of the compounds (I>, (II>, and (I[l)) that is a feature of the present invention is applied. A method of curing to form a silicone rubber layer.

In the method (1), as for the coating thickness of the composition containing the compound which is a feature of the present invention, a monomolecular film in a dry and hardened state is enough to obtain adhesion imparting performance, but if it is too thin, it will cause problems. There is a problem of areas where the silicone rubber layer does not adhere due to holes etc., and if it is too thick, there is a problem of suppressing the penetration of the developer, so the thickness is 0.01 to 0.5 micron, more preferably 0.05 micron. It is desirable that the diameter is from 0.2 microns. In general, the thickness of the silicone rubber layer coated on top of the silicone rubber layer can be set arbitrarily, but if it is too thick, it will be prone to scratches, and if it is too thick, it will be difficult to peel off the silicone rubber layer during development, resulting in poor image reproducibility. Therefore, the thickness is preferably from 0.5 microns to 10 microns.

In the composition containing the compound that is a feature of the present invention in method (1), it is also useful to add the following substances. Examples include a coating solvent, a catalyst that promotes the condensation reaction of hydrolyzable groups, a known adhesion promoter, an organopolysiloxane, a reinforcing filler, and a silicone ff14n agent.

When these compositions are applied onto a photosensitive layer, it is common to volatilize the solvent by heating, and it is optional whether or not to crosslink the nonvolatile components at that time.

In the method (2), compounds (I), (■), which are the characteristics of the present invention, are added to the uncured silicone rubber composition.
, (III) can be added in an arbitrary amount, but desirably, the organic group having a urethane bond, the organic group having a urea bond, or the la group having the structure (A) is added to the silicone after curing. 0.005 to rubber layer
It is effective to set the addition amount to 10% by weight, more preferably 0.05 to 5% by weight. This is because when the amount is too small, there is a problem of insufficient adhesive strength, and when it is too large, there is a problem that it is not only uneconomical but also reduces the ink repellency.

In method (2), the thickness of the silicone rubber layer can be set arbitrarily, but for the same reason as mentioned above, it is from 0.5 microns to 10 microns.
Preferably microns.

In methods (1) and <2), after the silicone rubber is cured, the hydrolyzable groups of compounds (I), (n), and (I[I) become crosslinking points to form a crosslinked structure of organopolysilokinane. It will react and exist inside.

The waterless lithographic printing original plate according to the present invention is manufactured, for example, as follows. First, a composition solution to form a photosensitive layer is applied onto the support using a conventional coater such as a reverse roll coater, an air knife coater, a Meyer bar coater, or a rotary coating device such as a Whaler, and then dried and coated as necessary. After heat curing, if necessary, a composition containing at least one of the compounds (I>, (II>, and III) is applied onto the photosensitive layer, and after drying, a silicone rubber is applied thereon before curing. The composition solution is applied in a similar manner and heat treated for several minutes, usually at a temperature of 50''C or higher, to fully cure and form a silicone rubber layer.

If necessary, a protective film of a polymer such as polyester or polyolefin is covered over the silicone rubber layer using a laminator or the like.

The waterless lithographic printing original plate of the present invention thus produced is exposed to actinic rays through, for example, a vacuum-adhesive negative film or positive film. The light source used in this exposure process is one that generates abundant ultraviolet light, and can be a mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a tungsten lamp, a fluorescent lamp, or the like.

The printing plate is then rubbed with a developing pad containing a developer al solution to remove at least the silicone rubber layer in the image area, yielding a printing plate in which the exposed surface of the photosensitive layer or substrate serves as an ink-receiving surface.

As the developer used in the present invention, JP-A-60
-Developer shown in 28656 A') Aliphatic hydrocarbons (hexane, hebukun, kallin, kerosene, etc.),
The following polar solvents or polar solvents and water added to aromatic hydrocarbons (toluene, xylene, etc.) or halogenated hydrocarbons YI (t'ricrene, etc.) are suitable.

Alcohols (methanol, ethanol, etc.) Ethers (dioxane, etc.) Cellosolves (ethyl cellosolve, methyl cellosolve,
butyl cellosolve) carpitol lupitor esters (ethyl acetate, del cellosolve acetate, methyl cellosolve acetate, tol acetate, etc.)
It is.

When the printing plate smoothed in this manner is mounted separately for offset printing and printed without applying dampening water, a printed matter with excellent image reproducibility is obtained.

[Example] Examples are shown below. Parts in the examples are parts by weight.

In addition, the scratch strength test method in the text is as follows. In other words, continuous loading type scratch strength tester (TYPE
-HE ICON-18>, a sapphire needle with R = 0.5 mm was scanned at a speed of 60 crn/min, and the non-image area of the printing plate was treated with an organic solvent "Isopar E" manufactured by Esso Corporation.
While immersed in H, scratches are made while applying continuous load. The scratched printing plate is printed using a flatbed proofing machine that does not use dampening water, and the load on the areas where ink is receptive is measured.

This means that a printing plate with a large load that causes ink adhesion due to scratches has excellent scratch strength.

Table 1 shows the chemistry (
The 111 model is shown. A commercially available product or a product synthesized by the method of (e) above from which unreacted substances were removed by distillation under reduced pressure was used.

Examples 1 to 18, Comparative Examples 1 to 5 Sumitomo Durez Co., Ltd. was placed on an aluminum plate with a thickness of 0.24 mm.
Coat phenol formaldehyde resol resin (Sumirai 1 to Resin PC-1) to a thickness of 1 micron,
Cure for 3 minutes at 0 0'C! It was used as a substrate.

A tetrahydrofuran solution having the following composition was applied thereon and heat treated at 125°C for 35 seconds to form a photosensitive layer with a thickness of 2 microns.

(1) Phenol formaldehyde novolak resin with a number average degree of polymerization of 5.6 and naphthoquinone-1.

Partial esterification product with 2-diazide-5-sulfonic acid chloride (esterification rate 49%) 100 parts (2) 4.4-diphenylmethane diane 1 to 30
Part (3) Dibutyltin diacetate-1 to 0.2 part C
A silicone rubber silicate having the following composition (solvent n-heptane/methyl isobutyl ketone = 85/15 weight ratio) was coated thereon with a vacuum cleaner, and dried and cured at 120'C for 4 minutes. 2 microns thick.

(1) α,ω-dihydroxypolydimethylsiloxylene (number average degree of polymerization 20,000> 100 parts (2)
Vinyltris(methylethyl-oxime)silane
10 parts (3) Dibutyltin diacetate - 1-0.01 parts (4) Additives listed in Table 2, added ♀ Zara ni Toshishiku Co., Ltd.) r! A printing original plate was prepared by laminating the polypropylene film with "Trephan" (thickness: 10 microns).

Negative film is vacuum-adhered to the iqed original printing plate,
Exposure was carried out for 60 seconds using a metal halide lamp "Idol Fin 2000J" manufactured by Uwa Denki Co., Ltd. at an illuminance of 11 mW/- in Oak Seisakusho'@JUV Meta-rUV402AJ.Then, the film was peeled off and n-hebutane/
When developed using a developing pad containing a developer made of ethanol (50150 weight/distance ratio), the silicone rubber in the exposed areas was removed and the photosensitive layer was exposed, while the silicone rubber layer remained in the non-exposed areas. A printing plate with good reproducibility or a printing plate with poor image reproducibility in which the silicone rubber layer had peeled off in both the exposed and non-exposed areas was prepared. The image reproducibility results are shown in Table 2. Example 1
Comparing Comparative Example 1 with Comparative Example 1, it can be seen that the compound, which is a feature of the present invention, has adhesive properties and provides good image reproducibility.

A printing plate with good image reproducibility was attached to an offset printing machine, and using Toyo Ink Co., Ltd.'s iceless lithographic ink,
When printed without using dampening water, 1q of printed matter was obtained with excellent image reproducibility.

Regarding printing plates from which printing plates with good image reproducibility were obtained, printing plates were stored at room temperature for 3 days after the production of the plate, and printing plates were stored at 40°C and 70% RH for 30 days thereafter. The scratch strength of each printing plate was measured by 1q from the original plate. The measurement results are shown in Table 2. Hereinafter, those meeting the former condition will be referred to as initial printing plates, and the latter will be referred to as archival printing plates.

As is clear from Table 2, the scratch strengths of the printing plate blanks of Examples 1 to 18 hardly change after storage, whereas the scratch strengths of Comparative Examples 2 to 5 decrease with storage.

Examples 19 to 27, Comparative Examples 6 to 10 On the same substrate as in Example 1, 52 digits of the same photosensitive layer as in Example 1 were formed.

Then on each side, the compounds listed in Table 3 were added to n-heptane/
A composition dissolved in methyl isobutyl ketone (85/15 m maximum ratio) was applied and heated at 100'C for 2 minutes to form an intermediate layer. The thickness of each intermediate layer is listed in Table 3.

Next, a silicone rubber composition (n-hebutane solution) having the following composition was coated 5 on the intermediate layer and heated at 120'C for 4
A silicone rubber 1εj was applied for 1 minute.

(1) α,ω-dihydroxypolydimethylsiloxane 1 unit (number average degree of polymerization 20,000> 100 parts (2
) 10 parts of vinyl 1 to lith(1 to methyl ethyl to oxime) silane (3) 0.01 part of dibutyltin diacetate Further, in the same manner as in Example 1, "Trefampa" was laminated thereon to form a printing original plate.

When the obtained printing original plate was imagewise exposed and developed in the same manner as in Example 1, a printing plate with good image reproducibility or a printing plate in which the silicone rubber layer was completely peeled off was obtained as in the above-mentioned Example and Comparative Example. was gotten.

The image reproducibility on each side is shown in Table 3.

The results show that the compounds constituting the intermediate layer shown in Examples 19 to 271 have adhesion imparting performance compared to Comparative Example 6, and give a mark 1: plate with excellent image reproducibility. .

The scratch strength of the obtained printing plates is shown in Table 3. Examples 19 to 27 maintain their strength even in archival printing plates, while Comparative Examples 7 to 10 maintain their strength in archival printing plates. The strength will decrease.

Examples 28-35, Comparative Examples 11-12 On the substrate shown in Example 1, phenol formaldehyde noholac resin with a number average degree of polymerization of 5.6 and naphthoquinone-1,2-diazide-5-sulfonic acid chloride were added. 4
A solution of 9% esterified product in Te1-lahydrofuran was applied and dried at 80'C for 1 minute to form a photosensitive layer. thickness 2
micron.

A silicone rubber composition similar to that of Example 1 containing the additives shown in Table 4 in the indicated amounts was coated on the photosensitive layer, heated at 120'C for 4 minutes, and a thickness of 2. A micron silicone rubber layer was provided.

Next, in the same manner as in Example 1, trefampane was laminated and a printed Kawahara board was made.

The iW-treated printing original plate was subjected to image exposure under the same conditions as in Example 1, and then exposed for 4 seconds. Next, peel off the "Trephan" and add 40"C diethylene glycol/monoethanolamine (95/5 ff1ffi
After immersing it in a solution (ratio), it was developed with water using a nylon brush to obtain a printing plate. Table 4 shows the image reproducibility of each printing plate. In the table, “good image reproducibility” means:
In the exposed areas, the silicone rubber layer and the photosensitive layer are removed, exposing the substrate and making it receptive to ink, while in the non-exposed areas, the silicone rubber layer remains. In the table, image reproducibility is poor when the silicone rubber layer is peeled off in both exposed and non-exposed areas, exposing the photosensitive layer or substrate.

A comparison of Examples 28 to 35 and Comparative Example 11 shows that the compounds shown in each Example have adhesion-imparting properties and provide printing plates with good image reproducibility.

In addition, as shown in Table 4, when the scratch strength of the archival printing plates was compared with that of the initial stamp plate, Examples 28-
Examples 36 to 40, Comparative Examples 13 and 14 It can be seen that those of Comparative Example 35 retain strength better than Comparative Example 12. Applying n-hebutane/methyl isobutyl ketone ('85/15% m ratio) containing the compound, 1
An intermediate layer was formed by heating at 00° C. for 1 minute. The thickness of each intermediate layer is shown in Table 5.

Next, a silicone rubber layer was provided on the intermediate layer in the same manner as in Example 9, and "TOREFAN" was laminated thereon to obtain a printing original plate.

When the obtained printing original plate was exposed and developed in the same manner as in Example 28, a printing plate with good image reproducibility or a plate with poor image reproducibility in which the silicone rubber layer was completely peeled off was obtained. The results for each are shown in Table 5.

Comparing Examples 36 to 40 and Comparative Example 13, it can be seen that the compounds shown in each Example have adhesion-imparting properties and provide printing plates with good image reproducibility: t).

Further, as shown in Table 5, when the scratch strength of the preservation mark 9: plate was compared with the scratch strength of the initial printing plate, Example 36
It can be seen that the strength retention is significantly superior to that of Comparative Example 14.

(Effects of the Invention) The present invention has the effect of increasing the adhesion between the silicone rubber layer and the photosensitive layer by incorporating the above-mentioned compound with an IV constant into the silicone rubber layer. It has the effect of maintaining high scratch strength over time, that is, high plate surface strength, compared to compounds with an adhesion imparting performance of 44.

Table 1-1 Structural formula and abbreviation of additive C112 CH3-CH (m is average 6) Table 1-2 Table 1-3 6to1° (random copolymer, m is average 5, n is average 20) q
(Comparative example) H2N(CH2)3si (OCH3)3r (Comparative example) TOμ Silicone Braimer D S (Comparative example) (CH3CH2CH2CH20r*Ti Table 2 Table 3 Table 4 Table 5

Claims (1)

[Scope of Claims] In a waterless lithographic original plate formed by laminating a substrate, a photosensitive layer, and a silicone rubber layer in this order, the silicone rubber layer is at least one of the following (I), (II), and (III). A waterless lithographic printing original plate characterized in that its main component is a silicone rubber obtained by containing one type of compound. (I) A silane or siloxane in which a hydrocarbon group has a urethane bond and a hydrolyzable group is directly bonded to a silicon atom; (II) A silane or siloxane in which a hydrocarbon group has a urea bond and a hydrolyzable group is directly bonded to a silicon atom; Siloxane, (III) Monovalent organic group represented by general formula (A), and silane or siloxane in which a hydrolyzable group or hydroxyl group is directly bonded to a silicon atom, formula (A) ▲Mathematical formulas, chemical formulas, tables, etc. are available▼ (In the formula, R^1, R^2, R^3, and R^4 are hydrogen atoms or monovalent hydrocarbon groups, and R^5 is a divalent hydrocarbon group)
.