DE2064380C3 - Photosensitive mixture - Google Patents

Description

The invention relates to a photosensitive mixture according to the preamble of claim 1.

Positive-working mixtures and copier materials based on o-quinonediazides are in the Reproduction technology used on a large scale. These compounds become too in the light of decomposition converted into a five-membered carboxylic acid, which is more soluble in aqueous alkalis than the undecomposed one Link. Such copying layers can also be higher molecular weight compounds, in particular Condensation resins, add to improve their copying and printing properties, but is not known that these additives are included in the light reaction. The connections have that Disadvantages that they are not very photosensitive and that they are thermally unstable.

Other known positive working mixtures consist essentially of hexaaryldiimidazolyien and condensation resins. Such copying materials, however, result in printing plates with only a small amount Efficiency.

From US-PS 28 92 712 are photodepolymerizable mixtures of polymers, for. B. polyacpials or polymethyl methacrylate, and photoinitiators, e.g. B. Benzoin compounds. known In order to achieve sufficiently short exposure times, the exposure is carried out there in the presence of a solvent for the depolymerization products. This is particularly necessary in the case of addition polymers of ethylenically unsaturated compounds in order to avoid reversible regression of the polymer. Nevertheless, relatively long exposure times are still used there for image generation.

The object of the invention is to provide a positive working photosensitive mixture with high photosensitivity and good storage stability to find copies with high mechanical strength lets develop

The invention is based on a photosensitive mixture whose solubility is increased by exposure and which contains a polymer with acidic substituents and an initiator Mixture is characterized in that the initiator is an N-heterocyclic compound which at least

ίο a pyridine, pyrazine or dihydropyrazine ring and contains at least one benzene ring as a substituent or in fused form and on these rings optionally carries further non-photosensitive substituents

Base of the heterocyclic nitrogen compounds contained in the mixture according to the invention acridine, phenazine and 2,3-diphenylquinoxaline are preferred. The heterocyclic orundic bodies preferably carry substituents or fused benzene

2n rings. Examples of suitable substituents are alkyl, alkoxy, nitro, dimethylamino, acetylamino and phenoxy groups and halogen atoms.

Preferred substituents are alkoxy, especially methoxy groups. In detail, for. B. the > the following connections can be used successfully:

9-phenyl-acridine

9-p-methoxyphenyl acridine

9-p-hydroxyphenyl acridine

9-acetylamino-acridine

Benz (a) acndin

10-methyl-benz (a) acridine

Benz (a) phenazine

9,10-dimethyl-benz (a) phenazine

9-methyl-benz (a) phenazine / 10-methyl

benz (a) phenazine
9-methoxy-benz (a) phenazine / 10-methoxy-

benz (a) phena / in
Dibenz (a, c) phenazine
11 -Methoxydibenz (a, c) phenazine
Dibenz (a, j) phenazine
Dibenz (f, h) pyrido (2,3-b) quinoxaline
6,4 ', 4 "-trimethoxy- ?, 3-diphenyl-quinoxaline
6-methoxy-2,3-diphenyl-quinoxaline
4- (4-methoxyphenyl) -2-phenyl-quinazoIine
6-chloro-4 ^ "- dimethoxy ^ -diphenyl-

quinoxaline
6.7 dimethyl-4'.4 "-dimethoxy-2,3-diphenyI-

quinoxahn

2,3-Di-pyridy! - (2) -5 aza-quinoxaline
2,3-bis (4-methoxyphenyl) -5,6-cirfiydro-

pyrazine

2,5-bis (2.4dimethoxyphenyl) pyrazine
2,3,5,6 Tcti akis (4-methoxyphenyl) -

pyrazine
"2,3-Diphenyl 5.6-d; hydropyrazine

Much of these compounds are already in the older DF-PS 20 27 467 and 20 39 861 as photoinitiators proposed for photopolymerizable mixtures

ho been. The dor! described effect consists in to stimulate certain monomers to polymerize under the action of light, the exposed ones Layer parts are hardened. In contrast to this, the mixtures according to the invention are based on the

exposed areas more soluble. So far nothing is known about the mechanism of the reaction that takes place known,

Are particularly preferred by the invention

measured heterocyclic compounds used in 9-position substituted acridines, especially that 9-phenylacridine, the 4 ', 4 "-dimethoxy-2,3-diphenylchmoxalm and its substituted in the 6-position Derivatives, especially the 6-methoxy derivative.

With particular advantage, it is also possible to use compounds which are created by linking the aforementioned heterocyclic compounds with reactive side chains of a polymer are obtained.

The mixture of the invention can be used commercially in the form of a solution or dispersion, e.g. B. as so-called Copy varnish, are recovered, which the consumer himself on an individual carrier, z. B. to Etching of molded parts, for the production of copied circuits, stencils, signage or screen printing forms, applied and, after drying, exposed and developed into an imagewise distributed layer.

The mixture can, in particular, also be in the form of a solid, photopolymerizable one located on a support Layer as light-sensitive copying material for the production of printing forms, relief images. Etch protection layers, stencils, mats, screen printing forms, color proofing foils or single copies in the trade to be brought. An important application is the production of storable presensitizers Printing plates for flat, letterpress and gravure printing.

The Gemi & jhe according to the invention stand out characterized by high sensitivity to light and excellent thermal stability. You have opposite Diazo compounds have the further advantage that there is no gaseous nitrogen in the copy layer during exposure developed »vird. They also enable the production of positive reliefs or letterpress forms. The high molecular weight polymers with light-sensitive heterocyclic Mtenketten have no tendency to crystallize and can therefore be added to the copying layers in relatively large proportions can be added.

The photosensitive mixtures also contain a high molecular weight polymer, the units with acidic Substituents. especially with carboxylic acid, phosphonic acid, Sulfonic acid or N-arylsulfonyl urethane groups in combination with other units. Copolymers with acrylic and Methacrylic acid esters.

The polymers form the main part of the mixture (based on solids). The heterocyclic Compound is generally used in an amount of from 0.5 to 30, preferably from 5 to 15 parts by weight added per 100 parts by weight of polymer.

The mixtures can also contain dyes. Pigments. Plasticizers, wetting agents and color formers added will. Such additives should preferably be chosen so that they do not affect the light reaction absorb necessary light.

If triplienylmethane or phenazine dyes are added to the layers, these dyes are added bleached out the areas hit by the light, so that an immediately visible image is obtained.

Suitable plasticizers or wetting agents are 7. B.

Triethylene glycol, dibutyl phthalate,

Polyoxyäthyjen-Sprbitan-Fettsäureesterj
Polyoxyäthyienäthyläther,
p-nonylphenol polyglycol ether and
Polywadhse.

With these additives the flexibility of the layer can be increased set and regulate the development speed wedge.

If the mixtures are to be applied to copper carriers, they can be used to improve the Adhesion organic sulfur compounds, e.g. B. 2-mercapto-benzothiazole, can be added.

The mixtures are preferably used in the production of letterpress forms, relief images, offset printing forms, Bimetal and tri-metal printing forms, copied circuits, screen printing stencils and Printing forms for gridless offset printing.

ίο If the mixture is in liquid form as a so-called Copy varnish stored and only immediately before use on the base, z. B. a screen printing support or a printed circuit board is to be applied, the layer components are in a suitable Solvent or solvent mixture dissolved or dispersed The solvents are alcohols, ketones, Esters, ethers, amides or hydrocarbons are suitable. Above all, the partial ethers become more polyvalent Alcohols, especially the glycols, are used.

The solutions or dispersions can advantageously be used directly for the production of printing plates after their production applied to a suitable support and the products obtained as photosensitive Copy materials are stored and placed on the market. Here can be the same or solvents similar to those used for the preparation of the copying varnishes. The application is made

z. B. by pouring, spraying or immersion.

As a support are z. B. zinc, copper,

for example aluminum, steel, polyester or acetate film or polyamide, the surface of which a pretreatment if necessary may be subject to.

If necessary, an adhesion-promoting intermediate layer is placed between the support and the light-sensitive layer.

i> layer or an antihalation layer applied.

The copier layers exposed in the usual way are expediently made with organic solvents developed e.g. B. acetone, methyl ethyl ketone, ethylene glycol monoethyl ether, Trichlorethylene or glycerine,

4n which, if necessary, water from upper acids, e.g. B. sulfuric acid can add.

If the developed copy material is to be used as a printing form, the layer can be raised by heating higher temperature, e.g. B. above 180 ° C, »

4) burns "to the abrasion resistance and thus the To increase the number of copies.

The following examples describe embodiments of the invention. All percentages and proportions are, if nothing else is specified than

W to understand amounts of weight. One part by weight (Gt.) corresponds to 1 g. if 1 ecm is selected as the volume part (Vt.) will.

example 1
jj A coating solution is coming out

2.5 Gt. a methyl methacrylate / methacrylic acid copolymer with an average molecular weight of about 32,000 and an acid number of 137.

0.01 Gt. Supranol blue GL (Cl.50.335).
20.0 Gt. Ethylene glycoimonoethyl ether

and increasing amounts of S ^ phenyl-acridine and on electrolytically roughened and by anodizing ft? hardened 0.3 mm thick aluminum by spin coating applied and dried at 100 ° G for 2 minutes.

The samples are then placed under a gray wedge, the wedge steps of which are around the exposure

: 0 64

distinguish tor 1.4, 2 minutes with a tube exposure device, which contains 13 fluorescent tubes of 4OW arranged on an area of 60 χ 60 cm-13, exposed

Developed for 30 seconds with ethylene glycol monoethyl ether, about 10% water and 10% conc. Contains sulfuric acid, and then with protective paint colored.

The results are as follows:

The light sensitivity increases with the initiator content. The following table I gives the number of full exposed, i.e. completely removed wedge steps and the number of intermediate steps in brackets after them with different 9-phenyl-acridine content.

Table 1 Table Il

initiator

Wedge steps

10

15th

Gt. 9-phenyl-acridine

Wedge steps

(U 5 0 Example 2 (1! 0.20 I-. ' (1-2) 0.30 4-5 (1-2) 0.45 5 (2) 0.60 6th (4) 0.75 9-10 (4)

A coating solution is made

2.5 pbw of the polymer described in Example 1,

0.2 pbw of 9-phenyl-acridine,

0.01 Gt. Supranol blue GLund

20.0 Gt. Ethylene ^{glycol monoethyl ether jl}

prepared and applied by spin-coating to electrolytically roughened aluminum hardened by anodization, the oxide layer of which is 3 g / m ² , and dried at 100 ° C. for 2 minutes. The dry layer weight is 5 g / m ² .

Then, as described in Example 1, exposed through a photographic positive original, developed for 15 seconds at acetone by immersion for removing the non-image areas and v with aqueous sodium, wiped over metasilicate * \ nschließend is rinsed with water, fixed with l% phosphoric acid, Colored with protective paint and, if necessary, gummed with an aqueous gum arabic solution for preservation.

The offset printing form obtained in this way delivers at least 100,000 perfect ones on an Offse 'printing machine Prints.

To improve the abrasion resistance, the offset printing form can be baked for 10 minutes at 240 ° C will. The print run then increases to at least 200,000.

B e i s ρ i e I 3

A coating solution is prepared according to Example 1 and added 0.2 pbw for sensitization. one Initiator offset as indicated below.

The exposure is carried out according to Example 1, the (, 5 Processing according to example 2.

The light sensitivities observed are given in Table II below:

6-chloro-4 ', 4 "-dimethoxy-2,3-

diphenyl-quinoxaün 6 (2)

9-phenyl-acridine 5 (2)

Benz (a) acridine 5 (2)

Benz (a) phenazine 2 (2)

6,4 ', 4 "-trimethoxy-2,3-diphenyl-2 (2)

quinoxaline

6-acetylamino 4'-4 "-dimethoxy-2,3-diphenyl-quinoxaline 0 (3)

Mixture of esters from naphthoquinone

(1,2) -diazid- (2) -5-sulfonic acid
and 2,3,4-trihydroxy-benzophenone 0 (0)

The one used for comparison · - known positive working diazo compound results in the specified amount even with a significantly longer exposure time no picture.

Example 4
A coating solution is made

0.55 Gt. of the polymer described in Example 5.

0.70 Gt. the initiator specified below,

0.005 Gt. of the phenazine color used in Example 1

fabric and
15.0 Gt. Ethylene glycol monoethyl ether

prepared and applied as in Example 1 to anodized aluminum and dried. The copy layer is exposed for 2 minutes under a gray wedge and 15 seconds with that given in Example 1 Developer developed Then it is fixed with 1% phosphoric acid and colored with fat paint

The initiator used is made by reacting a copolymer of methyl methacrylate and glycidyl acrylate with 6-carboxy-4 ', 4 "-dimethoxy-23-diphenylquinoxaline according to the US patent 34 18 295 specified process. The nitrogen content of the reaction product is 2.8%.

Example 5
A coating solution is made

2.5 pbw of a methyl acrylate / methacrylic acid copolymer with an average molecular weight of about 30,000 and the acid number 157

0.2 pbw of 9-phenyl-acridine,

0.1 Gt. Supranol blue GLund
20.0 Gt. Ethylene glycol monoethyl ether

prepared and spun onto anodized aluminum and dried. In a parallel experiment, the Copy layer with an I-2 μm thick overcoat provided with polyvinyl alcohol and processed similarly. Exposure and development are done accordingly Example 1.

If one compares the photosensitivity of the two samples, this is the case with the latter, with which the Post-diffusion that oxygen is inhibited by the overcoat during exposure is 180% higher.

This effect is also observed when other nitrogen-containing heterocycles are used as initiators.

Example 6
A coating solution is made

2.5 Gt. of a copolymer of methyl methacrylate and N-ip-ToluolstilfonylJ-carbamiclsiuirc- (O-me (hacryloxy) -älhylster (65:35, acid number 60),

0.4Gt. 9-phenyl-acridine,

0.004 Gt, Ethyl Violet (Cl. Basic Violet 4) And
20.0 Gt. Ethyicngiykolmönoäthyläthcr

prepared and on 0.3 mm thick, anodized aluminum thrown off.

After drying, 4 minutes on a 5 KW under a positive original or under a gray wedge Xenon spotlight lamp exposed and transmitted for 10 seconds Treatment with the developer specified in Example 1 developed. The quality of the received Image corresponds to that of the images described in Example 3.

Example 7

A coating solution is prepared according to Example 2, but without dye, and applied to a 125 μ in thick, biaxially stretched polyester film with a hydrophilic adhesive layer DE-AS 12 28414 is provided, thrown off and dried.

Exposure and development correspond to Example 1.

This copy can be mounted in an offset printer and used to make prints will.

Example 8
Line coating solution is made

2.5 Gt. Methyl methacrylate / acrylic acid copolymer with an average molecular weight of 60,000 and an acid number of 82.
Polyoxyethylene sorbitan monolaurate.
9-phenyl-acridine,

of a phenazine dye according to Example 1 and
Ethyicngiykolmönoäthyläthcr

K) specified developer developed by brushing over.

The thickness of the Kcipicrschioh'l is 0.43 mrh \ die Washout depth 0.185 min.

Instead of the l'olyä (hyleh-sorbi (iin-mon () laurats körihch also Polyoxyälhylünc'ctyiethcf, p-Nohylphcnolpo-

lyglykolä liier or triethyleneglycol can be taken.

The resulting relief images are good in their quality comparable.

Example 10

A coating solution is prepared according to Example 2 and added with O ₁ I Gt. 2-mercapto-benzlhiazole added. Then it is spun onto a cleaned copper surface of a Cu / Al bimetal plate, then dried for 2 minutes at 100 ° C.

The exposure is 2 minutes under a positive original or under a gray wedge according to Example I, then developed for 40 seconds with the developer given in Example I.

To produce a bimetal offset printing form, the exposed copper is etched with an Eisc-n-III chloride etch etched away within a minute, then wiped over with |% phosphoric acid and then mil Felt color cin-dyed.

Example Il

For the production of color proofing foils, four ßcschitfitungslösungen are prepared according to Example 2, but instead of the dye used there colored as follows:

a) Gclbfolic:

b) Rolfoil:
^{! i} c) Blue foil:

0.25 Gt.
0.4 (Jt.
0.01 (Jt.

20.0Gt.

prepared and centrifuged onto anodized aluminum and dried. The exposure is 2 minulene under a positive original or under a gray wedge corresponding to Example 1, developed for 30 seconds by immersion in trichlorethylene. Then with l% igcr Phosphoric acid fixed and cingcfärbl with fat color. the The printing form is ready for printing.

Example 9
F. A coating solution is turned off

2.5 Gt. of the polymer described in Example 1.

0.2 Gl 9-phenyl-acridine,

0.75 Gt. Polyoxyethylene sorbitan monolaurate and

5.0 Gt. Ethyl glycol monoethyl ether

prepared and on a 0.3 mm thick aluminum sheet w> infused. The majority of the solvent is allowed to evaporate at room temperature and then dries for 3 hours at 100 ° C.

To produce a relief image or a letterpress form, the copying layer is 20 minules mil m the tube exposure device according to Example 1 under a photographic positive original and then 5 minutes with the ί 0.07 CJt in example. IeUgclb3G

(CI 12,700).
0.08 CJt Zapon real fire red B

(CM. Solvent Red S09),
0.01 (3t. Ethyl violet l

(CI.BasicVioicM).
d) Black folic: 0.08 (today rettschwarz IIB

(C .1.26.150)

α "These solutions are each aufgesc a 37 μιη thick biaxially stretched Polyäthylentercphlhalalfolie! i! c" dCRT ii "dv / ic c 2 ^(T in Example! ^rrv cknc * Dsnn the layers under the corresponding Silberfilmfarbausz.ügen (3 minutes Blue or red folic,

a; 5 minutes of yellow or black film) exposed with a Röhrcnbelichlungsgeräl and developed for 15 seconds with the developer specified in Example 1.

When the extracts are obscured, they are stolen

-, η corresponding to the original of the silver film extracts Duplicate.

Example 12
A coating solution is made

"" 2.5 Gt. of the polymer described in Example 1. 0.2 (5t. Note (a) acridine.
0.01 Gt Zaponechtfeucrrot B (CI. Solvent Red 109)

and
20.0 (it. Ethylene glycol monoethyl ether

prepared and on an aluminum / copper / chrome trim plate whipped up and dried.

Then, as in Example 1, exposure is carried out using a negative original and with that there specified FnUvirklcr developed for 30 seconds.

The exposed chromium is mixed with a solution of 17.4% CaC "l ·. 35.3% 7nC" l ·. 2.1% HCI and 45.2% water etched away within 7 minutes and then

the paint layer removed with alcohol. Finally will Wiped over with ten percent phosphoric acid and with a greasy color colored. The trim metal plate is ready to print.

Example 13

To produce a zinc high pressure mold, a Coating solution

2.5 gi. of the polymer described in Example 1,

0.2 Gt. 4 ', 4 "-dimethoxy; 2,3-diphehylquinoxaline,

0.02 Gt. Ethyl violet (CI ^1. Basic Violet 4f and

20.0 Gt. Ethylene glycol monoethyl ether

prepared and applied to a cleaned one-step zinc etched plate by spin coating and dried.

It is exposed for 3 minutes with a tube exposure device according to Example!, Developed for 1 minute with the developer given in Example I.

Then the exposed zinc surface is cleaned with 6% nitric acid at a temperature of 6 minutes. The shape created in this way is suitable for quality letterpress printing.

Example 14
A coating solution is made

2.5 Gt. of the polymer described in Example 1, 0.2 pbw. 4'-tert-butyl-9-phenyl-acridine,

0.02Gt. of the dye used in Example 12

and
20.0 Gt. Ethylene glycol monoethyl ether

prepared and on a mechanically roughened, 0.3 mm strong aluminum foil applied by spin coating and dried.

Exposure and development are carried out as in Example 1. The quality of the printing form obtained corresponds to that described under Example 2.

Example 15
A coating solution is made

2.5 Gt. of the polymer described in Example 1, 0.2 pbw. 6-chloro-4 ', 4 "-dimethoxy-2,3-diphenylquin-

oxaiin,

0.25 Gt. of the wetting agent used in Example 8,
0.02Gt ethyl violet (CI. Basic Violet 4) and
15.0 g of ethylene glycol monoethyl ether

made and on a monofilament polyamide fabric that 120 threads per cm, applied and dried.

It is exposed for 5 minutes under a negative original using a tube exposure device according to the example 1 and then 2 minutes with the developer specified in Example 1.

The stencil obtained in this way can be used for screen printing.

Example 16

A coating solution according to Example 15 is applied to the cleaned copper surface of a carrier, which consists of a plastic plate with a laminated copper skin, fanned out and dried. Dry layer weight: 10 g / m *.

Then a tube exposure device according to Example 1 is used for 10 minutes under a positive original j exposed, developed for 30 seconds with the developer specified in Example I and then with an iron-III chloride solution of 42 ° Be for 20 minutes etched.

The copier layer used is characterized by a hefvöffaging corrosion resistance and a good one Resolving power off.

Example 17
A coating solution is made

^{| j} 2.5 Gt. of a methyl methacrylate / methacrylic acid copolymer with an average molecular weight of about 20,000 and an acid number of 95.
O ₁ OlGt. RhodamineB,
" ⁽ 0.2 pt. 2,3-bis- (4'-melhoxyphenyl) -

5,6-dihydropyrazine,
20.0 Gt. Ethylene glycol monoethyl ether

prepared on electrochemically pretreated 0.1 mm thick aluminum by spinning at 100 Applied revolutions per minute and 2 minutes at

100 ⁰ C dried.
Then the plate is placed under a positive template in the

Exposure at a distance of 72 cm with an 8000 W xenon lamp for 2 minutes. The development follows through Wipe over with that given in Example 1

Developer within 35 seconds.
After fixing with 1% phosphoric acid, it becomes

colored with bold color,
π The quality of the printing form obtained is similar to that described in Example 3.

Example 18
A coating solution is made

2.5Gt.

ö, i5 Gi.
0.01 Gt.
0.2 Gt.

20.0 Gt.

of the polymer described in Example 17,

Rhodamine B,

of the wetting agent used in Example 8

and

Cyclohexanone

prepared and on 0.1 mm thick, electrochemically pretreated aluminum by spinning at 100 Revolutions per minute applied. After drying, the plate is placed under a positive template 2 Minutes exposed from a distance of 72 cm by an 8000 W xenon lamp

This exposed plate is made in 45 by wiping over with the developer given in Example 1 Developed in seconds and colored with protective paint after treatment with 1% phosphoric acid.

The quality of the printing form obtained corresponds to that of that described under Example 17.

Claims (5)

Patent claims: t. Light-sensitive mixture, the solubility of which is increased by exposure, and which is a polymer with acidic substituents and contains an initiator, characterized in that the Initiator is an N-heterocyclic compound, the at least one pyridine, pyrazine or dihydropyrazine ring and at least one benzene ring as Contains substituents or in fused form and optionally not others on these rings carries photosensitive substituents 2. Photosensitive mixture according to claim 1, characterized in that the N-heterocyclic Compound is of high molecular weight and contains a large number of N-heterocyclic radicals 3. Photosensitive mixture according to claim 1, characterized in that the N-heterocyclic Compound an acridine, a 2,3-diphenyl-quinoxaline substituted by methoxy groups or a phenazine is. 4. Photosensitive mixture according to claim 1, characterized in that it is a polymer with Contains carboxylic acid, phosphonic acid, sulfonic acid or N-arylsulfonyl urethane groups. 5. Photosensitive mixture according to claim 1, characterized in that it contains 0.5 to 30 parts by weight of N-heterocyclic compound per 100 parts by weight Contains polymer.