DE1797352A1 - Presensitized bimetallic printing plates and methods for their manufacture and use - Google Patents

Description

PATENT ADVOCATE

DR. F. ZUMSTEIN - DR. E. ASSMANN DR. R. KOENIQSBERQER - DIPL.-PHYS. R. HOLZBAUER

TBLiFON: US4T0 and 221011 t V / O Ό C. TELeQRAMME: ZUMPAT 8MDNOHENa,

«5βΤ · ΟΗΕΟΚΚθΝΤΟ: MONCHeN B11SS BRÄUHAUeeTRAaSB 4 / M

BANK ACCOUNT: ■ ANKHAUe H. AUFHXUeeR

52

OIL. 5316

K-IC COBPOBATIOH, Hew York, BT.Y./USA

Pre-approved, bin-metal printing plates and processes eu their manufacture and use

The present invention relates to the manufacture of biro-metallic planographic printing plates from pre-enibilized bimetallic printing plates which have all photosensitive coating a photopolymerizable one Own allyl ester resin "

In photolithography, long-running prints and high quality reproductions can be achieved by using bimetallic plates can be achieved. Dieae verdea made by making a photosensitive material on the metal coating of a metal base plate. The metal of the base plate and the metal

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plating are chosen so that one is oleophilic or accepts part and the other is hydrophilic or Water accepts «When exposed with a light motif the photosensitive coating in the exposed Surfaces hardened while he was in.den not irradiated Share remains unaffected * After the exposure is made the plate is designed to remove the unexposed uncured coating, leaving the cured Image surfaces remain unaffected and unchanged. Then an etching solution is applied, which the Solder away the plating in the unexposed areas not protected by the hardened protective image, and thereby exposing the metal of the plate. subject Removal of the hardened protection gives a planographic printing plate with metal printing surfaces and φ non-printing metal under the grand.

Hydrophilic or water-accepting surfaces are usually aluminum, stainless steel, or chrome surfaces; The oleophilic or color-accepting surface is generally made of copper. A typical bimetallic one The plate structure consists of a plate Made of aluminum, the surrounding of which is one side plated with a thin copper base, which is with

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a photosensitive colloid containing biohromates » like a solution of gum arabic * which is an alkali metal dichromate contains, coated iBt. The coating must be applied immediately before exposure because it loses sensitivity when stored. the The plate is put into a pear-shaped, planographic printing plate converted by exposing them to a light image to produce a hardened protective image, removed the unexposed, photosensitive coating and etched away the unprotected upper copper layer, whether expose the top surface of the aluminum base plate. The resulting, developed plate is in the unexposed areas, where the copper up to the aluminum base has been etched away, hydrophilic, while after the removal of the protective image, the resulting copper surfaces have a hydrophobic character. When coloring in an offset printing press, the plate takes up on the copper areas that correspond to the exposed image area, color on and the printed proofs become then made. Since the exposed areas of such a plate take on the color, one speaks of a negative process.

Although it became a very desirable item

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a pear-shaped, pre-sensitized plate suitable for the production of a flat print is generally usable, not yet completed. Although numerous sensitized, resinous materials and Polymers in addition to the well-known bichromate colloids were tested, none of them proved completely satisfactory. What is required is a storage-stable, photosensitive, non-shrinking, solvent-soluble, film-forming material with the correct spectral responsiveness, which after exposure and development a robust, durable uad relatively Solvent-insoluble protective layers can form can be easily removed from the finished panel.

According to the present invention, a balanced

nete bimetallic printing plate made from a pre-e

be made bimetallic plate, by placing a sensitized coating of a crosslinkable Allyleeter resin applies, the coating with a light motif exposed, developed by removing the non-hardened portions thereof, the photopolymer! sized Bild al β protection to the lic kb remains, which is not from the Schute

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the covered metal layer is etched away and attached Protection removed

In practicing the invention, a bimetallic * presensitized printing plate is first made, by applying a sensitive ethyl ester resin coating on the plated side of a metal baaieplatte. The necessary for the production of such a plate * Allyleeter resins used are prepolyraorlsate, the by addition polymerization of an addition polymerizable carboxylic acid allyl ester with several aliphatic-ethylenically unsaturated bonds, preferably 2 to 4 »of which at least one is an allyl ester group represents, can be obtained. The polymerization is carried out under conditions that are used here for others It is described in more detail that at least one of the ethylenically unsaturated bonds, preferably one of the allyl groups bonded to a monomer, remains intact and is not converted. this leads to a polymeric system that consists of a chain

I I of -C-G units, each of which is an ali phatic-äthylenieoh unsaturated group tr & gt _f is preferably an allyl ester. These remaining, unsaturated centers enable such resins to photopoly-

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merlsation as soon as eiβ are formulated and used according to the present invention _o

The polymerization of allyl ester monomers in the previously This manner is known and is based on the fact that the polymerization between allyl monomers is faster proceeds as the crosslinking of the allyl ester group »or other unsaturated groups in the bar polymer. This Difference in reactivity enables the production of Isolation of the non-crosslinked allyl resin. The latter types of hardness are solvent-soluble, solid at ambient temperature and usually contain a very small amount Percent eats the initial monomers, so that when crosslinking or photopolymerization by Lioht very little shrinkage occurs. The aforementioned physical bigenso adhesives are desirable among those who use uncontaminated allyl ester resin excellent materials for the production of the pre-enrolled printing plates described here Brooks

Allyl esters, which are used to make crosslinkable Allyl ester resins can be used, siad generally those carboxylic acid esters in which elme or

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several carboxylic acid functions with an allyl group are esterified, whereby they can belong to the aliphatic or aromatic series.

To the crosslinkable, aliphatic allyl ester hareem belong to the following classes:

(A) prepolymers derived from allyl esters of unsaturated monobasic acids, either with the general formula ^c _n ^H 2n «-1 ^{C00R or C} n ^H 2ft-1-y ^X y ^C00Rf ZcB. _{Allyl acrylate, allyl chloroacrylate, allalymethacrylate t} allyl crotonate, allyl cinnamonate, allyl cinnamalacetate, allyl furoate and allyl furfuryl acrylate. That means that la all "formula used here". R represents an allyl group and η can be any integer from 1 to inclusive, but if the acid is unsaturated, then η is 2 to 17, y is 1 or 2 and X is a halogen, hydroxyl, phenyl ₃ substituted phenyl or pururfuryl group or an alkyl or alkoxy group with 1 to 4 carbon atoms.

(b) premium polymers made from allyl esters of unsaturated monobasic acids; ZcB. Allyl methaorylate with Butadiene, allyl methacrylate with methyl methaorylate,

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methacrylate with styrene, allyl methaorylate with vinylidene chloride, Allyl crotonate with methyl methacrylate, allyl crotonate with styrene, allyl crotonate with vinyl chloride, allyl crotonate with vinyl acetate, allyl crotonate with vinylidene chloride, Allylorotonate with diethylene glycol maleate, Allycinnamate with vinylidene chloride, allylcinnainate with Styrene, Allylc innamat with Cinnamylc Innamat, AllyIfuroat with styrene and allyl furoate with vinylidene chloride.

(c) prepolymers derived from allyl esters, aliphatic carboxylic acids with 2 or more allyl groups, where they have one of the following general formulas; C _n H _2n (COOR) ₂ , C _n H _2n-1 (COOR) ₃ , C _n

^G _a ^H 2n-1- ^ ⁰⁰⁰¹¹ V ° n ^H 2n-2 ^(C00H) 2 · ^C n ^H 2 _a - or ROOCOR, 2.B ₀ diallyloacalate, diallyl malonate, diallyl euccinate, diallyleebacate, diallyl maleate, diallyl fumarate, diallylitaoonate, diallyl tartrate , Diallyl carbonate, diallyladlpat, triallyl citrate, triallyl carballylate, diallyl malate and diallyl citraconate,

(d) prepolymers made from allyleaders aliphatic Carboxylic acids with two or more allyi groups; «S.B. Diallyl oxalate with vinylidene chloride, diallyl oxalate with styrene, diallyl malonate with vinylidene chloride, diallyl

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suocinat with vinyl acetate, diallyleuocinate with vinylidene chloride, dialyisuccinate with polyvinyl acetate, diallyl adipate with vinylidene chloride, diallylsebacate with vinylidene chloride, diallyl maleate with methyl methacrylate, Diallyl maleate with styrene, diallyl maleate with vinylidene chloride and dialyl carbonate with methyl methacrylate,

In the aromatic series, those are networkableea Resins derived from an allyl ester, in which the acid normally interferes with the benzene and naphtha! In series, typical monomers bind diallylieophthalate, Diallyl terephthalate, triallyl mellitate, tetraallyl pyromellitate, iriallyl cyanurate and the like.

In the production of crosslinkable allyl ester resins, auoh known as prepolymers, the monomeric materials are polymerized in the usual way, with a Dissolution of a soluble polymer in the monomer up to mim point is made just before the gelation that then occurs when the crosslinking of the polymers reaches the point where it becomes insoluble in the monomer. These polymer i eat loounge η or thick tie ige item are then converted into a solvent-soluble Prepolymer fraction and a monomer fraction

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separates. This can be achieved by treating with one Solvent, “rich” the monomer, while ee the polymerized part precipitates, or by others Auxiliaries that provide a soluble prepolymer, which is practically free from monomers. A typical method for separating such crosslinkable prepolymers is described in US Pat. No. 3,030,341.

In order to obtain coatings which photopolymerize quickly enough to be technically useful, it is necessary to add a sensitizing agent to the prepolymer which absorbs quanta, dissociating into free radicals which accelerate the complete polymerization of the prepolymer. The sensitizing agents can be benzoin ethers such as methyl ether or benzoin; Benzophenone, ρ, ρ'-sabstituierte Bensophenone such as 4,4 ^I -Bie (dimethylamino »o) -benzophonon and 4.4 ^l -Bie (diethylamino) -benBoph" Noji | or Biβ- (1-anthraquinonylanino) -anthraquinones such as 1,4-Bls- (1 -anthraohinonylamino) -anthraohinone and 1,5-bis-O-anthraquinonylajainoJ-anthraquinone and combinations thereof. Other useful sensitizing agents include polynuclear quinones, such as xanthone, 1,2-

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Beneanthraquinone and 2-Methylanthraohinonj mononuclear Quinones, such as 2> 5-diphenyl-p-quinone; aromatic OC-difcetones such as benzil; substituted aryl methylenedioxy compounds, V7ie piperonal, piperoin, 3,4-methyleadioxy-alcohol and 5,6-methylenedioxyhydrindoa-i; substituted ß-haphthoselenazolines, such as 1-methyl-2-acetylmethylene-ß-nephthoeelenazolini, B-substituted B-benzothiazolines, such as 3- ^ ethyl-2-benzoylmethylenebenBthiaaolia.j substituted ß-naphthothiaaolin, such as 1-methyl-2-benaoylmethylene ~ ß-naphthothiaaolin; Anthrones, like Anthronj Beneanthrone, like Benz-2-äthylbemzaÄthron tuxd 7 ~ H-Ben «(de) -anthraj5en-7-one; and Azabenzanthrone, «in 2 ~ Keto-? Haethyl-1,3-diasabenaathrome

I) The concentration of the sensitizer in the photopolymerizable composition is dependent on the intrinsic sensitivity of the crosslinkable allyl ester resin present. In a typical case, where then Hare is the prepolymer of the allyl isophthalate, about 1 to 20 #, preferably 1 to 5 wt. anthraohinone needed. Some sensitizers, such as ρ, ρ ¹ -substituted benzophenones, e.g. 4 _t 4'-Biβ- (dinethy1-aoiino) -benzophenone cause less than

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1.5 + «a considerable increase in sensitivity to light. The sensitizer is excited by real quanta, which in turn initiates the polymerization. In all reactions it is assumed that the sensitizer dissociates into free radicals by light quanta or absorbed energy and that the resulting free radicals initiate the crosslinking of the prepolymer, whereby it becomes insoluble. The addition of the sensitizer to the allyl ester prepolymers increases their reactivity to light quanta by 100 to 200 times. During exposure, the films polymerize sufficiently quickly that they can be used in conventional plate-making processes.

The use of the prepolymer, which is essentially free of monomers, about 2 to 3 % monomer, ensures that the photosensitive coating, as soon as it is free of the solvents that were used to spread the film, gives a non-tacky coating Crosslinking and the insolubility of the prepolymer does not shrink when exposed to constant radiation, which ultimately leads to an exact reproduction of the work of art *

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The sheet metal materials used here exist from an oleophilic or color-accepting metal plating, which is based on an oleophobic or color-repellent Metal surface is applied. The dye-accepting layer is preferably copper clad onto an aluminum sheet, the aluminum sheet then as a carrier and as an oleophobic or non-staining surface »

Another suitable basic construction, the so-called trimetallic plate consists of a base plate, or Foil, with a metal layer, e.g. copper, on which ale oleophilic layer is plated and this in turn is plated with another metal e.g. chrome to serve as a hydrophilic layer. Such a record would represent a positive experience. From the point of view For photolithographic purposes, the trimetallieohβ Plate a bimetal! See plate type, the third The metal layer only serves as a base support. The Paohmann chooses that particular combination of basic materials that makes his own special Erfarderaisswi serve at the beaten.

The inventive, prJiaensib meierten, bimotallic

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Such plates are converted into a metal planographic printing plate by being presensitized Plate exposed with a Liohtmotiv, whereby dae crosslinkable allyl prepolymer resin on the exposed Make further polymerized or heard «you Plate is then developed by observing the β-polymerized allyl hsrs, corresponding to the unexposed Part of the plate that dissolves, causing the dye-attaching Copper layer is exposed. This is' with an etching solution, as it is common in photolithography, removes and brings the dye-repellent Aluniniu »- surface sum appearance Xn this context is ammonium persulfate in particular is useful because it is so can be formulated that it only attacks and removes the copper and leaves the base ua attacked. The developed and etched plate is then treated with buckets of organic solvent, with scrubbing or nioht rubs, to the photopolymerA Schute see below remove and expose the dye-accepting copper surfaces, creating a full-metal planographic printing plate with a dye-accepting copperplate. printing surface and a dye off-repellent aluminum surface.

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The liquids used to make the uncured allyl ester resin film from the aight-exposed Removing or dissolving the area is more advantageous Way relatively high-boiling organic solvents such as la. generally used in most lithography shops. A preferred solvent is tetrahydrofurfuryl phosphate, excellent solvents also include aromatic hydrocarbons and their chlorinated derivatives, such as Toluene, xylene, chlorinated xylene, chlorinated toluene, chlorinated aliphatic hydrocarbons, e.g. trichlorethylene, trichloroethane and the like, higher-boiling ketones, esters of glycol ethers, such as Eater d Ethylene glycol monoethyl ether (Gellosolve ** 7 and Eeter of diethylene glycol monoethyl ether (Carbitol ™. Such solvents can be used alone or in mixed combinations or as emulsions in water. The protection is achieved using solvents of the the aforementioned type removed by scrubbing.

The gate part of the prS-Bensilized plates produced according to the invention is the remarkably large Storage stability, longer than a year, and the excellent protection quality of the photopolymer protection

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which is extremely impermeable to its chemicals. A Another desirable characteristic of the allyl protective resins is that they have very little undercutting of the copper or the hydrophobic Allow layer, creating a remarkably harsh and a clear print is produced.

The present invention is further illustrated by the following examples without, however, _r be limited thereby:

example 1

A solution of a photoeneitive coating, as he is for The manufacture of sensitive printing plates is used, it is produced as follows:

12.0 g diallyliaophthalate prepolymer (Dapon M) 68.0 g pentoxone (4-methoxy-4-methylpentanone-2) 0.1 g benzil

0.1 g Mi chier's ketone

0.4 g xanthone

The PrSpolymerisat is dissolved in Fentoxon, the LCsuag

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purified to insoluble matter duroh filtering or Remove centrifugation. A Photosenaibilieator, like benzil, Michler's ketone or xanthone alone or in combination it is dissolved in Pentoxon and carefully mixed with the polymer solution. The solution to the Coating v, ird then using a

Slingshot device onto a commercially available from W

"Printing Development, InCc" purchased bimetallic Plate applied with an aluminum overlay or Contains base carrier plate on which a thin, electrolytically deposited copper coating with a Thickness of about / | b, 1 mil to 1.0 mil) is present. the photosensitive solution is applied to the copper coating

2,5,4.1 (T ⁴ Cm introduced and forms a uniform layer of / (0.1 mil) thickness. Hachdem a part of the solvent has evaporated, the plate ^c j minutes 51.7 ⁰ O (125 ⁰ P ) Λ

heated to most of the remaining solvent to remove. After cooling, the photosensitive coating appears as a dry film on the plated Metal. The tightened plate is lowered when it is lowered Illumination intensity. ^ Ehandhobt, as it ia is customary in record-making companies. the Plate is made using a carbon arc, a mercury vapor lorape or another * internal

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siren source of ultraviolet light dttroh «negatively exposed in the yellow-tone glass image. The exposure is enough if a strength level "7" in a 21-level Seneltlvltateskale is reached · The development of exposed plate is carried out by inserting it into Xylene is immersed in order to remove the non-hardened or non-polymerized resin from the canvas. whereby the copper of the picture surface remains ge a cn ut et, however, exposed in the Kicht image areas of the plate will. To complete the Bildest development is a lithographic etching "solution of the commonplace". Type say- ; ends and rubbed over the plate until the topper is in the non-picture areas has been completely removed. Subsequently, a de-sensitized phosphorus-hardening agent known in the specialist field ("desensitized phosphoric gum etch "), including dae AIwIn1na in the hicht-Bildbe ^ · '^ en hydrophilic or waseerannehsend to make and .aalt printing inks deviating from su aaonen. Of the Schute is then removed by scrubbing with water « whereby one uses a stencil remorer in the photolithographleohen (apply balloons stencil remorer). Finally, the completely bare metal surface of the plate is treated with a conditioning agent for. Copper treated like it is used to make an IJapfer- ί r>

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image for printing ink sensitive «u flat» alternative a dilute nitric acid solution can be used, to prick the copper picture capable of recording »

In the following example the procedure of the example repeated using the following solutions used:

Example 2

1.5 g of allyl methacrylate prepolymer 2.5g methyl isobutyl ketone

2.5 g cellosolve acetate

0.05 g benzene

0.01 g 4.4 ^f -Bis- (dimethylamino) -beasophencn.

The materials were mixed with slight expectation until all parts were solved. ”Then Once the solution was filtered, it was ready for use.

Example 3

2.4 g of a prepolymer made from a copolymer of a monoally ester of an unsaturated acid, such as

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Allyl methacrylate with styrene, are in a mixture from 5.0 g of methyl isobutyl ketone and 5.0 g of cellosolve acetate dissolved with gentle heating and stirring. Be damn 0.48g benzoin methyl ether for lusting the resin in Solvent added and mixed until dissolved. After filtering, the composition is ready for use.

Example 4

1.5 g diallyleuccinate prepolymer 5.0 g methyl isoamyl ketone 0.04 g piperonal 0.02 g of 4,4'-bis (dimethylaaiino) -ben »ophenone.

Example 5

1.5 g diallyl maleate prepolymer 5.0 g methyl isoamyl ketone ° »02 g 4,4 * -bis- (dimethylamino) -benzopheao».

Example 6

1.5 g prepolymer from a copolymer Diallyl maleate with methyl methacrylate

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5.0 g celloaolva acetate

0.02 g of 4,4'-bis (dimethylamine) -beaeophenoii.

Example 7

1.5 g prepolymer of a mixed polymer

Allyl dinnamate with styrene 2.0 g methyli-butyl ketone 2.0 g xylene 1.0 g cellosolve acetate 0.05 g 2-keto-3-methyl-1 _t 3-diaj5aben an throned.

Example 8

The procedure of Example 1 was repeated, but in this case the base plate failed Aluminum substrate covered with a thin layer of electrodeposited copper, "that in turn electrolytically deposited with a thin layer » Chromium was plated as the top layer. Yes this one For example, the photopolymerizable allyl prepolymer was deposited or applied to the top chromium layer. Because chromium has a hydrophilic »character owns and represents the nioht-druokende plan, will

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according to the present example one

Plate made; Examples 1 to 1, negative-working plates, exposure, development, etc. proceed in the same way as in the first example, in this case it is of course necessary to use an etching solution for the bed of the chromium, but one that does not dissolve the copper interlayer, which remain intact »

must, as it serves as a hydrophobic printing surface · Such Chrox etching solutions are known in the trade «.

The plates Examples described above, prepared according to both negative ale _v include also positive working types can be used long, and provide copies of the order of one million ·

The permanence of these Pl achdruokiae tallplattea, her- ™ posed via presensitized overviews that both

Having extended storage stability as well as sharp image reproduction, the technology with a photomechanically produced printing plate enriches with advantages that none of the previously known possesses.

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Claims (1)

PATENT CLAIMS: Process for making a bimetalll see ' planographic printing plate, characterized in that (i) on a bin »metallic base material, which consists of two composed of superimposed metal layers is »of which one accepts printing ink and repels the other printing ink, a photopolymerizable composition is applied which (a) a crosslinkable one Contains allyl ester resin, which polymerizes iron addition polymerizable carboxylic acid allyl ester bit several aliphatic-ethylenically unsaturated Biaduagea, at least one of which is an allyl ester group, was obtained, whereby this resin has a confirmed bond and a solvent-soluble » Material is that at the lowering temperature represents a 7th substance and that in the further polymerizat solder by actinic irradiation at room temperature little shrinkage and (b) contains a sensitizer that contributes to the absorption of actinic radiation Room temperature accelerates the polymerization of the PrE polymers mentioned; (Ii) this upper layer is exposed with a Liohtnotlr, producing a hardened, photopolymerized image 109812/0740 ,, .BAD OFUGlNAL (iii) the coating is developed, not hardened To remove parts of it »whereby the« phot op olymeri eiert Image as protection aurliekble ibt? (iv) the plate is validated with a Wsxmg which the upper metal layer not covered by the protection dissolves and thereby exposes the under “MtetallecJlicht j uad (v) the protection is removed to cover the remaining emde To expose metal layer. 2. The method according to claim 1, characterized in that it that the pear-shaped building material with a copper plating on it, which carries the photopolymerizable backing " 109812/0740 BATH