DE2107286A1 - Photoresist process - Google Patents

Description

Photoresist process

Photoresists are light-sensitive materials that can be used to add pictures solid substrates, such as metal, wood, ceramic surfaces, glass, plastic, synthetic resin, textiles, leather, Selectively reproduce synthetic or natural rubber.

Such photoresists are made from mixtures, which are normally soft or liquid, but which are transformed into one by actinic radiation such as ultraviolet light solid product can be cured or polymerized. Such mixtures are referred to as photocurable or photopolymerizable. In general, a very thin layer of the resist mixture is applied to the substrate applied, imagewise either directly with a point radiation source or through a grid or a photographic negative or positive with actinic radiation, for example exposed to ultraviolet light,

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After the imagewise exposure, the uncured or unpolymerized resist is removed in the non-image areas, leaving the solid support in these areas is exposed. The base can then be etched with such materials that the base dissolve, but do not attack the photocured or photopolymerized resist. For documents with a metal surface aqueous acids or bases are generally used as suitable etching agents. With plastic pads organic solvents are preferred.

The present invention relates to a photoresist method to produce an image in a solid base, which is characterized in that one

a) applying a photo-curable mixture to the surface of the base, which consists of

k 1) a polyene with at least two reactive un

saturated carbon / carbon bonds each Molecule and

2) consists of a polythiol with at least two thiol residues per molecule,

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where the total functionality of the unsaturated carbon / carbon turns per molecule in the polyene and that of the thiol residues per molecule in the polythiol is greater than k ₃

b) after which the photo-curable mixture is exposed imagewise to radiation ₃ so that the exposed parts of the mixture are cured selectively,

c) after which the unexposed parts of the mixture are made removed from this surface and

d) the exposed or exposed parts of the surface of the substrate are etched away.

The imagewise exposure _3, which is expediently exposure through an image-containing transparency or mask, leads to selective hardening of areas of the poly / polythiol mixture.

The polyene / polythiolite becomes too upon photo-curing hardened to a solid product, which is believed to be a crosslinked Is polythioether. This product can be considered insoluble

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made because there are solvents in which the exposed product is insoluble and the unexposed product Product is soluble. The exposure is followed by removal of the. unexposed mix, so that the required areas of the .unterlage under a layer of the photo-cured polyene / polythiol mixture lag behind. The invention can be used to create desired areas in photoresists, printed circuit boards, in electronic or electrical circuits, in photoelectric molding processes, in chemical etching, in Engraving printing, the photo-etching process, the photo-engraving process and for the production of name tags and the like to generate or to cover. The above-mentioned polyene / polythiol blend was found to be excellent Has properties that make it particularly suitable for use as a photoresist composition. These mixes namely, 1) adhere firmly to the substrate and do well when photo-curing or photo-polymerizing, or both; "furthermore, the mixture is not affected by the etchant for the base, but it can be easily processed in the end." remove with a solvent that does not affect the protected areas.

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One type of the method according to the invention is to be explained in more detail below, for example in connection with the manufacture of a printed circuit board. The base is a printed circuit board in the form of a 1.5 mm thick phenolic resin plate or base made of polyethylene terephthalate, as is generally the case with used in the manufacture of printed circuit boards; this plate has a 35.6 u thick copper layer. The plate is usually cleaned with a polishing detergent and dried. The light-curable The resist mixture is poured onto the surface of the copper layer and forms a corresponding layer their surface, excess photocurable mixture can be removed by holding the plate vertically or by making it evenly thick Coating removed the excess with a doctor blade.

The photocurable layer is either in direct contact with it or with a corresponding air gap in between a mask or an original, which can be a photographic negative of an electrical circuit can, hung up. This layer structure is then in the

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Vacuum frame of a printing machine inserted and 2 seconds exposed to a highly intense light source for up to 2 minutes or more. A radiation with one wavelength from 2,000 to 4,000 S is sufficient to cover the exposed photoresist material to harden sufficiently. After exposure, the layer is developed by putting the plate in a Introduces solvent, for example, in an aqueous detergent solution that contains the uncured Pnorresist mixture dissolves, but no longer attacks the hardened mixture.

^w The plate is preferably placed in a solvent which is stirred by a bath moved by ultrasound, the unhardened areas being removed within 1 second to about 1 minute. This process for dissolving the uncured polyene / polytniol mixture is described in the parallel patent application P 19 08-169.7.

The plate is then ready for the etching process and has the image of the electrical circuit on the copper surface; this image consists of a film of hard, dry, photohardened resist material. The surface of the pad that. is not fed by the resist image

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therefore made of pure copper. This exposed copper can with an appropriate acidic etchant, for example a ferric chloride solution can be removed. The plate is then "placed in a conventional spray-etching device, which sprays the ferric chloride solution onto the surface. The concentration of the ferric chloride solution has for example 38 ° trees. Within a few minutes, the bare unprotected copper surface is on the plate completely etched away. The plate is then thorough rinsed to remove any trace of ferric chloride and then dried. At the next step in the process, namely the removal of the hardened photoresist material, is only done if desired, as it can sometimes be beneficial can use the cured photoresist layer as a protective coating for the electrical circuit to be left in place. The plate is cured in a solvent for the photo Material, for example immersed in chloroform or toluene, to remove the photohardened resist image and to release the bare copper circuit. The finished copper plate can then be rinsed in hot water and dried will.

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The polyene contains at least two unsaturated, non-aromatic carbon / carbon bonds, ie ethylene bonds or acetylene bonds. The number of these bonds per molecule is referred to below as the functionality of the polyene. The "polythiol" contains at least two SH radicals per molecule, the number of these radicals per molecule being referred to as the functionality of the polythiol. For example, a triene has a functionality of 3. If the polyene and polythiol both have a functionality of 2, this is Sum of the functionalities 4, and the curing reaction produces an essentially linear polythioether. However, if the sum of the functionalities is greater than 4, a crosslinking takes place during the curing, with a three-dimensional network of crosslinks being created in the polythioether molecule generally polythioether has a greater solvent resistance, heat resistance, ^-. and resistance to deformation under load, than the linear polythioether Accordingly, the sum of the functionality should be greater than 4.

In general, the polyenes have a molecular weight of 50 to 20,000 and a viscosity of 0 to 20 million cP at 70 ° C; they have the general formula YES

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where X is a radical R-G = C- or R-CHiC and m

Il

RR

has at least the value of 2, where R is hydrogen, halogen, aryl, substituted aryl, cycloalkyl j substituted cycloalkyl, aralkyl, substituted aralkyl, alkyl or substituted alkyl of 1 to 16 Represents carbon atoms -and A is a polyvalent organic radical. A can be cyclic radicals or smaller Amounts of heteroatoms such as N, S, P or 0 contain but usually primarily carbon / carbon, Carbon / oxygen or silicon / oxygen compounds without unsaturated carbon / carbon bonds. With Unsaturated reactive carbon / carbon bonds are referred to as bonds with the -SH radicals of the PoIythiols can react. Practically this concerns a non-aromatic, i.e. ethylenic or acetylenic double bond, which takes part in a radical polymerization can participate.

The non-aromatic carbon / carbon unsaturated bonds can occur in the terminal region of a branched chain; they can be terminal

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or close to the terminal region, i.e. no more than 16 carbons from the end of the Main chain in the molecule, and there can be two or more such unsaturated bonds per molecule be. For example, a diene is a polyene compound that has two non-aromatic carbon / carbon double bonds possesses per molecule. Combinations or non-aromatic double bonds and triple bonds within fc half of the same molecule are also possible, as for example with monovinylacetylene. For the sake of brevity all these compounds are referred to below as polyenes.

One group of polyenes suitable for the present invention is given in German patent application P 17 20 856.9 described. In these compounds, the radical A has no (1st) reactive unsaturated carbon / carbon bond and (2) unsaturated radicals in conjugation with the reactive carbon / carbon unsaturated bonds in the X radical. Allyl terminated compounds that have at least two -CO-NH bonds are preferred as polyenes. Polyenes of this type are also in the German patent specification P 18 02 559.7. Preferred polyenes of the first group include the following compounds:

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a) the reaction product from 1 mole of tölylene diisocyanate with 2 moles of the dialkyl ether of trimethylolpropane;

b) the reaction product of 1 mole of a polymer Diisocyanates with 2 moles of allyl alcohol;

c) the reaction product of 1 mole of polyethylene glycol, preferably with a molecular weight of about 1500, with 2 moles of Talylen-2, * t-diisocyanate and 2 moles Allyl alcohol;

d) the reaction product of 1 mole of a polymeric hexol, preferably with a molecular weight of about 700, with 6 moles of allyl isocyanate;

e) the reaction product of 3 moles of a polyester diol, preferably with a molecular weight of about 3000, with 2 moles of allyl alcohol and 4 moles of tolylene-2 _S 4-diisocyanate.

The second group of those useful in the present invention Polyenes are unsaturated polymers in which the double bond or triple bond is primarily in the main chain of the molecule occurs, examples are below other conventional elastomers, which are primarily derived from the usual diene monomers, such as polyisoprene, Polybutadiene, styrene-butadiene-carbon, isobutylene isoprene,

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Polychloroprene, styrene / butadiene / acrylonitrile rubber and the same; unsaturated polyesters, polyamides and polyurethanes derived from monomers that form a contain reactive unsaturated double bonds, such as adipic acid / butenediol, 1,6-hexanediamine / fumaric acid and 2,4-tolylene diisocyanate / butenediol condensation polymers.

^ A third group of polyenes for the present invention are compounds in which the reactive unsaturated carbon / carbon bond is in conjugation is present with adjacent unsaturated radicals, as for example in German patent P 19 51 485.3 are described.

Another group of polyenes relevant to the present Invention are suitable, are compounds which (a) the reaction product of (i) an organic epoxide with "at least two -CH-CH- residues with (ii) hydrazine, one

^v 0

primary or secondary amine or a salt of a tertiary amine, an organic alcohol or thioalcohol or an organic acid, wherein the reactant (ii) has at least one non-aromatic unsaturated group

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contains, or (b) the reaction product from (iii) a organic epoxide with at least one non-aromatic unsaturated radical with (iv) hydrazine or an organic Compound which contains at least two radicals which have a hydrogen atom which is linked to an epoxy radical of the Reactant (iii) is reactive and has the following formula: '

-N-, -N ⁺ -H, OH, -BH, -SH or -PH.

H
Polyenes of this type are described in German patent application P 20 09 620.2. A particularly preferred polyene of this type is the reaction product of the diglycidyl ether of bisphenol A with allylamine or diallylamine in a molar ratio of 1: 2.

The polyenes used according to the invention generally have a viscosity of 0 to 20 million cP at TO ⁰ C. This also includes polyenes which exhibit such viscosities with an inert solvent, as an aqueous dispersion or with a plasticizer. The molecular weights of the polyenes are usually in the range from 50 to 20,000 and preferably between 500 and 10,000.

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The polythiols are simple or complex organic compounds with an average of two or more branched or terminal -SH radicals per molecule. Siehaben usually a viscosity of 0 and 20 million centipoise at 70 ⁰ C, measured with a Brookfield Viskosiineter; this also includes compounds that are within this range with an inert solvent as an aqueous dispersion or with a plasticizer. Habit ^. The molecular weight is between 50 and 20,000 and preferably between IGO and 10,000. Suitable polythiols are described in patent application P 17 20 856.9. Examples of polythiols, which are particularly preferred because of their low odor, are esters of thioglycolic acid (HS-CH ₂ COOH), '- mercaptopropionic acid (HS-CHCCH ₃ ) -COOH) and ß-mercaptopropionic acid (HS-CH ₂ CH ₂ COOH) with polyoxy compounds, such as glycols, triols, tetraols, pentaols or hexols. Typical examples of preferred polythiols are ethylene glycol bis (thioglycolate), ethylene glycol bis (ß-mercaptopropionate), trimethylolpropane-tris (thioglycolate), trimethylolpropane-tris (ß-mercaptopropionate), pentaerythritol-pentaerytopropionate), pentaerythritol-pentaerytopropionate (thioglycolate) , Polypropylene glycol bis (ß-mercaptopropionate) and tris-hydroxyethyl-isocyanurate-trisCß-mercaptopropionate). Polymeric polythiols contain thiol-terminated stylcyclohexyldimercaptan polymers, but these are less preferred.

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Functionality is the average number of non-aromatic unsaturated radicals and thiol radicals per molecule in the polyene or polythiol. The functionality of the polyene or polythiol is usually expressed in whole numbers, although in practice the actual functionality can be a fraction. For example, a polyene with a nominal functionality of 2 may actually have an effective functionality of slightly less than 2. In the case of an assumed synthesis of a diene from a glycol, in which the reaction takes place 100% , the functionality for 100% pure starting products is theoretically 2.0. However, if the reaction only takes 90% , then about 10 % of the molecules present have only one double bond, and traces of compounds without functional residues can still be present. Since about 90 % of the molecules have the desired diene structure, the product as a whole then has an actual functionality of 1.9. Such a product is also suitable for the method according to the invention and is referred to below as one with a functionality of 2.

The polyenes and polythiols mentioned can optionally

can also be formed in situ and in the case of the invention «Procedure hardened quickly.

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The polyene / polythiol mixtures can optionally contain further additives, such as antioxidants, accelerators, Dyes, inhibitors, activators, fillers, pigments, antistatic additives, flame-retardant additives, thickeners, thixotropic additives, surface-active additives Substances, viscosity modifiers, extender oils, plasticizers and gowns to increase stickiness. The additives should not be substantially impermeable to actinic radiation. Such additives are usually added to these compounds beforehand before or during the mixing of the polyene with the polythiol. Suitable fillers are described in German patent P 17 20 856.9. It'll be common up to 500 parts by weight of additives per 100 parts by weight of the polyene / polythiol mixture is used, preferably from 0.005 to 300 parts by weight.

^ The mixture usually contains at least 2 wt. one Polyene and at least 2 wt. a polythiol. The weight ratio these two components can vary between 49: 1 and 1:49. The mixes are common liquid or flowable at the appropriate temperatures. Many products are flowable at room temperature.

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The processing and manufacture of the components of the ■ photocurable mixtures before exposure to UV radiation can be done as described in the earlier applications mentioned above.

The preferred radiation for carrying out the curing takes place with actinic radiation, in particular an electromagnetic radiation with a wavelength of about 2,000 to 4,000 8, because of the simplicity, Economy and easy handling. When using visible light or ultraviolet radiation it is usually necessary to use a photo-curable composition containing a curing accelerator contains, such as a photo-exciter, generally in an amount of 0.0005 to 50 wt / s, based on the total amount of polyene and polythiol. Suitable Accelerators are described in patent application P 21 00 031.7 or in the other applications mentioned above.

Radiation other than visible radiation or UV light can also be used to trigger the curing reaction used; accelerators are usually not required in this case. However, there are none

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Concerns about providing a corresponding accelerator that causes a curing reaction with the radiation in question triggers. Other suitable types of radiation are image-wise aligned bundles of ionizing radiation, preferably high-energy particle radiation, gamma rays or x-rays. Examples of particle radiation are positive ion radiation such as protons, cc-particles and deuterons as well as electrons and neutrons. The charged particles can receive a corresponding acceleration, such as with a Van de Graaff generator, a cyclotron, a Cockroft Walton accelerator, a resonance cavity accelerator, a betatron, a G.E. resonance transformer or a synchrotron. In addition, can Particle radiation is also used by cathode tubes, radioactive isotopes or an atomic pile will. Gamma rays or X-rays can be from radioisotopes, for example from cobalt 60 or through Particle bombardment can be obtained from a suitable source.

The dosage for the irradiation is usually between 0.0001 to 25 megarads per second. The dosage can be considerable with ionizing radiation

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Frames vary, from 1 megarad or less to 10 megarads or more for electrons, preferably 0.02 to 5 megarads. With gamma rays or X-rays one can work with 0.0001 to 5.0 megarads. The irradiation is usually carried out at room temperature, but can also take place at temperatures below room temperature up to such temperatures, at which the substrate begins to decompose.

When using ionizing radiation, the depth of penetration depends on the density of the material to be penetrated Materials. When the ionizing radiation is used in the form of electrons, usually 0.2 to 12 million electron volts (Mev) used. at Gamma rays or X-rays usually operate in a range of 0.01 to 5> 0 Mev. This area allows penetration of the aluminum up to a depth of 25 / rev up to 30 mm or with titanium from 25 / rev up to 20 mm and for plastics from 25 / U to 10 cm or more and for wood, textiles and paper from 50 to 20 cm.

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Preparation of the polyenes example 1

1 mole of diglycidyl ether of bisphenol A with a molecular weight in the range from 370 to 384 and 2 moles of diallylamine were placed in a beaker at 25 ° C. The reaction was carried out with stirring for 18 hours exothermic, the reaction temperature being left below 80 ° C. The allyl-terminated liquid thus formed Prepolymers are referred to as prepolymer A in the following.

Example 2

1 mole of liquid polymeric diisocyanate was placed in a resin kettle equipped with a condenser, stirrer, thermometer and gas inlet and outlet. Furthermore, h g of dibutyltin dilaurate were added as a catalyst. 2 moles of allyl alcohol were slowly added, the temperature being kept below 80 ° C. because of the exothermic reaction. After the allyl alcohol had been added, the reaction was continued for a further 15 hours at 70 ^° C. under nitrogen. The allyl-terminated liquid prepolymer formed in this way is referred to as prepolymer B in the following.

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Example 3

1 mol of commercially available tolylene diisocyanate was placed in a kettle as in Example 2; then 2 moles of diallyl ether of trimethylpropane were slowly added. After the addition had ended, 4.0 g of dibutyltin dilaurate were added as a catalyst and the reaction was continued for 30 minutes at 70 ^° C. under nitrogen. The allyl-terminated liquid prepolymer formed in this way is referred to as prepolymer C in the following.

Example 4

1 mol of commercially available polyethylene glycol with a molecular weight of 1450 and a specific density of 1.21 was placed in a vessel according to Example 2 under nitrogen. 2.9 g of dibutyltin dilaurate were added to the kettle as catalyst together with 2 moles of 2-tolylene, ¹ l-diisocyanate and 2 moles of allyl alcohol. The reaction was carried out at 60 ° C. for 2 hours with stirring. Subsequently was

Worked for 2 hours under a vacuum of 1 mm Hg at 6O ⁰ C in order to remove excess alcohol. This CHp = CH-terminal prepolymer had a molecular weight of about 1950 and is referred to as prepolymer D in the following.

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Example 5

g of hexol with a molecular weight of 68 * 1 were
into a 1 liter four neck flask under nitrogen
HO ⁰ C heated under vacuum for 1 hour. Afterward
the product was cooled to about 60 ° C. and 0.1 ml of dibutyltin dilaurate was added, after which 83 g were slowly added
(1 mole) allyl isocyanate was added to make the
Temperature remained in the range of 70 to 80 ° CP during the addition. After the addition was complete, the reaction was still
1 hour at 70 ⁰ C continued. The obtained polymer
Hexaene polyene had a molecular weight of about 1200,
a viscosity of 300 cP at 70 ⁰ C undwird hereinafter referred to as prepolymer E.

Example 6

Into a 1 liter four-necked flask, 808 g of a PoIyesterdiols having a molecular weight of 3232 and 0.1 ml ψ dibutyltin dilaurate and heated to HO ⁰ C. Of the

The flask was left under vacuum at this temperature for 1 hour. It was then cooled to about 50 ° C. and flushed with nitrogen, a mixture of 10 g of allyl alcohol and 60 g of tolylene-2, ⁱ <-diisocyanate being added at a moderate rate via a dropping funnel.

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The reaction was allowed to proceed for 15 minutes. Because of the exothermic reaction, a maximum temperature of 90 ° C was generated. The polymer product obtained was solid at room temperature, but ^{liquid at 70 °} C .; it would have an average molecular weight of about 10,500, a viscosity of 270,000 cP at 70 ^° C. and is referred to as prepolymer F in the following.

Process for the manufacture of the printed circuits Example 7

1 mol of prepolymer A from Example 1 was mixed with 1 mol of pentaerythritol tetrakis (ß-mercaptopropionate) and 1.5 g Benzophenone processed into a photohardenable mixture. This mixture was uniform in one layer thickness of 1.25 / rev on the copper surface of a circuit board applied, which is made of a 50 u thick copper layer on a polyethylene terephthalate film of the same thickness was. The photocurable mixture was through an image, namely through a negative of a printed Circuit with an air layer of 175 / U spacing by means of exposed to a 275 watt sunlamp for 5 minutes with an intensity of ^ 000 microwatts / cm. After removing the

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Original image has been washed off the uncured unexposed area of the photo-curable mixture by dipping the circuit board in a vice agitated with ultrasound bath containing a 0.1 #ige aqueous cleaning solution of 60 ⁰ C. The circuit board was dried and then placed in a conventional spray etching device which sprayed a 38 ° Baume ferric chloride solution onto the copper surface. Within 10 minutes, the exposed copper layer was removed, leaving the copper circuit board, which was still protected by the cured photocurable mixture. The circuit board was freed from the ferric chloride solution by washing, dried and then immersed in a chloroform bath to swell the cured mixture. The swollen hardened mixture was then removed so that the copper circuit was exposed on the base.

Example 8 to .12

The procedure according to Example 7 was used in each case, but now using 1 mol of the prepolymers in each case B, C, D, E and P with half a mole or 1 mole or 1/2 mole or 1 1/2 mole or 1/2 mole pentaerythritol tetrakis (ß-mercaptopropionate) to which benzophenone was added to give a photohardenable mixture. the Results were essentially the same.

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Example 13

It was worked analogously to Example 7, but with now 1.5 moles of prepolymer C and 2.0 moles of tris (hydroxyäthylJisocyanurat-tris-Cß-mercaptopropionate) the following formula were added. Essentially the same results were obtained.

CH ₂ CH ₂ -SH

0 C = O "0

t η it

OCH ₂ CH ₂ -N N-CH ₂ CH ₂ OC

f f I

O = C C = O C IT. '

CH ₂ -SH

dd 0

Example 1 * 1 .

The procedure was analogous to Example 7, except that the photocurable mixture of 1.5 mol of prepolymer A now and 2 moles of trimethylolpropane-tris-mercaptopropionate) and 1.5 g of dibenzosuberone instead of 1.5 g of benzophenone. The results were essentially the same.

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Chemical etching Example 15

A 1.25 / U thin layer of the photocurable mixture according to Example 13 was applied evenly to a 0.15 mm thick aluminum sheet, and a 0.025 mm thick transparent polyethylene film was applied over the photocurable layer. This layer structure was covered on the polyethylene film side with a photographic line image master and exposed from above for 5 minutes with a 275 watt sun lamp with a surface intensity of h, 000 microwatts / cm. After removing the negative, the cover layer was removed and the image developed by washing the aluminum foil with ethanol to remove the uncured resist. The aluminum substrate, which was dried in the air and containing the image, was then treated on the image surface only with a 50% HCl at room temperature. After 1 minute, the entire exposed area of the aluminum foil was chemically etched through.

Example 16

Example 15 was repeated, except that the coating, the formation of the image and the development were described in FIG Way on both sides of the aluminum foil

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were carried out so that two identical images were superimposed on opposite sides. The chemical etching was effected by immersing the metal foil in a bath of the etching solution.

The following examples demonstrate the use of the photohardenable photoresist compositions in photoengraving.

Example 17

A customary 1.6 mm thick zinc foil was treated to dryness with a cloth that was moistened with a benzene solution of a photo-curable photoresist mixture consisting essentially of 1 mol of prepolymer A according to Example 1, 1 mol of pentaerythritol tetrakis (ß-mercaptopropionate) and 1.2 g of dibenzosuberone. The photocurable mixture was exposed for 1 minute through a negative original with a 275 watt sun lamp with a surface intensity of ² J,000 microwatts / cm to cure the exposed parts of the photocurable mixture. The original image was removed and the unhardened, unexposed parts of the photocurable mixture were washed off by immersing the plate in an ultrasonic bath with ethanol at 60.degree. The plate

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was dried and then in a usual powder-free Etching device introduced, where they are treated with a nitric acid bath, was etched until a relief depth of 0.8 mm was obtained. The photo-engraved plate was in a usual printing press used as a template and gave letters or character images of good quality.

With chemical etching, metal layers from 12.5 to 50OyU can be produced without difficulty with tolerances from 5 to 125 / U depending on the type and thickness of the metal. Larger metal layers can also be removed by etching however, a proportional increase in tolerance, usually 0.25-0.5 of the total thickness, is taken into account must become. The metals that can be etched according to the invention are extremely diverse and can, for example, aluminum, aluminum alloys, Bronze, copper, carbon steel, stainless steel grades, tool steel and nickel silver alloy} be alloys.

The thickness of the photo-curable photoresist layer depends on the desired photographic resolution. For images that require a large photographic resolution, such as for example, lines and spaces up to 5, u width, should

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'Photoresist layers of about 0, ^. U thickness used will. With a lower photographic resolution, thicker layers of photoresist can be used will. A photohardenable photoresist layer 0.4 to 125 #u thick is suitable.

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Claims (1)

Claim e 1/. Use of a mixture as a photoresist mixture for application to a metal surface for exposure to etch the areas of the metal that correspond to an image, characterized in that the mixture ^ (1) a Pölyen with at least two reactive unsaturated carbon / carbon bonds per molecule and (2) contains a polythiol which has at least two thiol residues per molecule, with the total functionality of the reactive unsaturated carbon / "Carbon bonds per molecule in the polyene and the thiol residues per molecule in the polythiol greater than * i is. 2. Use of a mixture according to claim I _5, characterized in that it is used for the production of printed circuits. 109836/1 365 3. Photoresist process for the production of an image on a solid support, wherein one a) applying a photo-curable mixture to the surface of the substrate, b) exposing the photo-curable mixture imagewise to radiation and thereby selectively exposing the exposed Parts of the mixture harden, c) removing the unexposed parts of the mixture from the surface and d) etching away the exposed parts of the surface on the substrate, characterized in that a mixture is applied in process step a) which consists of 1) a polyene with at least two reactive carbon / carbon unsaturated bonds per molecule and 2) a polythiol which contains at least two thiol residues per molecule, the total combined functionality of the reactive unsaturated carbon / carbon bond per molecule in the polyene and the thiol residues per molecule in the polythiol being greater than H. 109836 / 1.3 65 4. The method according to claim 3 »characterized in that that, as a further process step, the parts of the polyene / polythiol mixture which are produced after the process step d) left behind, removed from the substrate. 5. The method according to claim 3 to 4, characterized in that that the mixture is applied to a metal surface. 6. The method according to claim 5 _s, characterized in that the mixture is applied to the metal surface of a base which is a plate for printed circuits and has an electrically insulating base layer. 7. The method according to claim 3 to 5, characterized in that that the imagewise exposure in process step b) is exposure through an original. 8. The method according to claim 3 to 7> characterized in that that the image is a graphic material consisting of letters or numbers, or the representation an electrical circuit. 109836/1365 9. The method according to claim 3 to 8, characterized in that that in process step b) the mixture with radiation having a wavelength of 2,000 to 4,000 8 exposed. 10. The method according to claim 9> characterized in that a polyene / polythiol mixture is used in process step a) applies, which contains an accelerator for photocuring. 11. The method according to claim 3 to 10, characterized in that that in process step a) a mixture is applied which contains a polyene which A) the reaction product of (i) an organic epoxide with at least two -CH-CH- residues with (ii) hydrazine, a primary or secondary amine, a salt of a tertiary amine, an organic alcohol or thioalcohol or an organic acid, wherein the reactant (ii) is at least one non-aromatic Contains unsaturated carbon / carbon bond, or B) the reaction product of (iii) an organic epoxide with at least one non-aromatic unsaturated carbon / carbon bond with (iv) hydrazine or 109836/1365 an organic compound that contains at least two radicals that represent a hydrogen atom contain which is reactive with an epoxy radical of the reactant (iii) and the Formula: -N-, -N ⁺ -H, -OH, -BH, -SH or PH Has. 12. The method according to claim 11, characterized in that the polyene is the reaction product of 1 mole of diglycidyl ether of bisphenol A with 2 moles of diallylamine. 13 · Method according to claim 3 to 10, characterized in that that the polyene is the reaction product of 1 mole of tolylene diisocyanate with 2 moles of the diallyl ether Is trimethylol propane. lh. Process according to Claims 3 to 10, characterized in that the polyene is the reaction product of 1 mol of a polymeric diisocyanate with 2 MpI of allyl alcohol. 109836/1365 15. The method according to claim 3 to 10, characterized in that that the polyene is the reaction product of 1 mole of polyethylene glycol with a molecular weight of about 1500 with 2 moles of tolylene-2, I-diisocyanate and Is 2 moles of allyl alcohol. 16. The method according to claim 3 to 10, characterized in that that the polyene is the reaction product of 1 mole of a polymeric hexol with a molecular weight of about 700 and 6 moles of allyl isoeyanate. 17. The method according to claim 3 to 10, characterized in that the Pplyen is the reaction product of 3 moles of a polyester diol with a molecular weight of about 3,000 with 2 moles of allyl alcohol and k moles of ethylene-2 ₃ ⁱ -diisocyanate « 18. The method according to claim 3 to 1 ?, characterized in that that the polythiol is a pentaerythrx tetrakis (ß-mercaptopropionate), Trimethylolpropane tris (ß-mercaptopropionate) or tris (hydroxyethyl) isoeyanurate tris (ß-mercaptopropionate) is. 109836/1365 19. Printed circuit, characterized in that the electrically conductive parts have a protective layer from a solid polythioether. 2Ö. Printed circuit according to Claim 19, characterized in that that it is laminated to a base layer. ue: wy 109836/1365