DE2721292B2 - Process for the production of a thermosetting synthetic resin coating with a structured surface - Google Patents

Description

The invention relates to a method for producing a thermosetting synthetic resin coating with a structured Surface, especially made of transparent or translucent unsaturated polyester resin, in which the structured surface is produced by passing through an under the cover The applied layer creates sections in the topcoat at a slower rate cure than the remaining part of the top cover, so that shrinkage occurs during curing and that with lower speed hardening sections pulled out in the direction of the shrunk part be, so that the thickness of the coating on the sections with the formation of depressions is considerable is decreased.

ίο is a process of the type described above from DE-OS 19 42 780 become known. In this case, a print sample is provided on a carrier base a printing ink is formed which has a hardening retarder or accelerator for the to be applied over it Synthetic resin coating then contains the synthetic resin coating due to the If this retarder or accelerator is present, that part of the coating will harden that over the print color forming the print pattern

μ lies, decelerates or accelerates during the rest Part hardens normally To apply the synthetic resin coating, for example, solutions are unsaturated Polyester resins in monomeric vinyl compounds immediately before processing with a catalyst, such as a peroxide, and an accelerator added and the thus obtained reactive Solutions then applied to the printing ink.

This process has the disadvantage that the polymerization is mixed with catalyst and accelerator

Solution sets in very quickly and the solution within

becomes unusable for a short period of time if it is up is not processed there. For this reason, the process is only used discontinuously

The invention is based on the object

Process for the production of a thermosetting synthetic resin coating with a structured surface so that the risk of premature gelatinization the set resin solution is switched off and its processing time at the discretion of the

Processor can be done.

In the method described at the outset, this object is achieved according to the invention in that a radical polymerization initiator for the continuous production of the synthetic resin coating on a carrier substrate, Sensitizers, accelerators, activators, promoters and / or crosslinking agents for the curing of the synthetic resin coating containing active base layer applies the active base layer in sections with barrier-forming substances

jo sees that a difiusion or migration of the under the proportion of initiator, sensitizer, accelerator, activator, promoter located in these sections and / or prevent crosslinking agent upwards, and finally applies the synthetic resin coating.

With the method according to the invention, the disadvantages of the known method are overcome by that use is made of the active basic method known from DE-AS IO 17 960. This Method is based on the idea of making a synthetic resin coating by applying two separate ones To produce layers and their chemical reaction with one another. Both layers consist of the respective starting components of the coating which, when they come into contact with one another, cause hardening cause the same. The respective solutions for the active base layer and the synthetic resin coating are relatively durable. The rapid initiation of the reaction only occurs when the initiator,

Sensitizer, accelerator, activator, promoter and / or the crosslinking agent from the active base layer diffused into the applied synthetic resin coating. This has the great advantage that, with the method designed according to the invention, fully s continuous, d. H. from roll to roll, with optimal Degree of cure, d. H. with the lowest residual monomer content, can be worked.

The method according to the invention differs from that described at the beginning in DE-OS 19 42 780 known method basically in that the curing of the synthetic resin coating causing substances (initiators, sensitizers, Accelerator etc.) not in sections, d. H. in shape a print pattern, but in the form of a continuous base layer. To this According to the invention, the base layer becomes barrier-forming substances in sections (in the form of a print pattern) applied These substances have the task of a migration or diffusion of the initiators, Sensitizers, accelerators, etc. from the base layer into the plastic coating applied to it to prevent. Consequently, act in the invention Do not process the substances applied in sections by chemical means, as is the case with the known processes are the case, but rather form a "physical barrier" for the curing process the synthetic resin coating causing substances. The method according to the invention thus works without the use of inhibitors or retarders. The barrier-forming agents used according to the invention Substances are as such indispensable components of a printing varnish, while according to the Teaching of DE-OS 19 42 780 the printing varnish additionally hardening retarder or accelerator added Need to become.

The colored printing of the active base with composite according to the invention, i. H. the barrier-building Pigmented printing varnishes containing substances appear in the transparent resin coating a structuring exactly in accordance with the pattern printed on the active base, similar to an embossing effect. Such colored textured Resin coatings are used to apply to various substrates, experience has shown that they have been tried and tested for wall and Ceilings, interior fittings for automobiles, airplanes and campers, for Manufacture of furniture, doors and the like. In addition, those produced according to the invention can Coatings also on laminated or non-laminated metal foil substrates, in particular made of aluminum, be applied. These can be applied to plywood or chipboard, for example, and then used as a reflective or insulating panels for ceiling and wall cladding of apartments, airplanes, Campers etc. are used.

The following compounds, for example, are used as barrier-forming substances: Binders based on zeolite derivatives, Hydroxyethyl cellulose, cellulose acetate, cellulose acetobutyral, nitrocellulose or their combinations, Polymethyl methacrylate and rosin esters, such as methyl esters of rosin, modified pentaesters and pentaerythritol esters, hydrogenated methyl esters, maleic acid-modified esters and glycerol esters and pentaerytimes thritester of polymerized rosin, vinyl chloride Acrylate copolymers with active hydroxyl groups, allyl-modified polymeric plasticizers with a hydroxyl number of 40 to 50, polyurethanes and polyacrylonitrile.

Other barrier-forming substances are pigment preparations, their carrier material consists of a modified rosin ester with a small number reactive groups of the rosin

One embodiment of the method according to the invention is characterized in that one with Applying an active base layer with a peroxide component. Excellent results can be achieved with this achieve that surprise insofar as it could not be foreseen that printed on the active ground Substances would be able to prevent the peroxide, which dissolves rapidly in esters, from immediately penetrate into those sections of the applied transparent synthetic resin coating which be in contact with the substances mentioned. Although substances have become known that, on Plasticized PVC films are applied to prevent the plasticizer from getting into other surfaces or surrounding media to immigrate As such, for example Polymethyiinethacrylai?! s a barrier plastic substance in US-PS 34 16 948 described. Barrier plastics have also been used in recent years Actually, they have a low gas permeability, with polyacrylonitrile on top. For the However, such substances are by no means in the prior art in the present application described.

In the synthetic resin sections, the peroxide causes gel formation and hardening of the immediately onset unsaturated synthetic resin, coupled with a simultaneous decrease in volume, which is caused by its contraction forces thin out the not yet gelling and hardening synthetic resin coating sections to embossing-like colored structures that lie deeper in the level, which are linked to the Active base printed patterns are identical, so that an embossed printing effect is created.

Since the free-radical initiators from the Aktivgrund work from the bottom up, this takes place immediately gel formation, hardening and contraction in the same direction, beginning in sections.

A wide variety of possible combinations can be carried out with the method according to the invention. For example, a synthetic resin coating containing an accelerator can be applied. As an alternative or in addition to the content of free radical initiators, the active base layer can be used also contain a photosensitizer, which breaks down into radicals under the influence of UV rays. as Barrier-forming substances or in addition to these pigments are used, so that high-energy UV rays are prevented from removing the photosensitizers that lie under the applied pigments, Decay into radicals at the same rate as the uncovered photosensitizers. In addition to an active base layer containing a photosensitizer, an act » applied vator containing synthetic resin coating.

However, an active base layer containing an activator and a photosensitizer can also be used containing synthetic resin coating are applied, then portions of the activator are covered. Finally, active base layers can also be provided, which are both a photosensitizer and also have an activator.

The hardening of the synthetic resin coating can thereby

can be supplemented, accelerated and qualitatively improved that one already has a structuring Resin peeling cures optimally with the help of a photopolymerization and thus a surface with the lowest residual monomer content

Adapting the active basic process according to the invention for the production of a thermoset Synthetic resin coating with a structured surface offers an additional option, which is in it is that you the from bottom to top curing action by initiators, etc. with a additional, but from top to bottom acting hardening process completes what in an optimal Through hardening of the outermost parts of the already structured coating results. By applying itself known lacquer solutions in thin layer by means of nozzles or printing on the structured coating surface, this thin layer acts as one, so to speak nittiVucCKsCiiiCiit, uä they suitable nuuiüVe cmiiait, uic the layers underneath optimal, d. H. with the lowest residual monomer content, able to harden are. In addition, this applied thin layer improves the in the filmed and crosslinked state Stacking and blocking resistance of the end product.

In addition, the active top layer and the outermost Adjacent UP resin layer by adding a UV sensitizer with the help of photopolymerization are optimally cured.

UV sensitizers consist, for example, of benzoin derivatives as well as combinations of benzophenone and other aromatic ketones with catalysts, e.g. B. Amines.

The method according to the invention will now be clarified with the aid of the drawing and its description, whereby

F i g. 1 is a schematic representation of a machine Process possibility for the continuous production of a thermoset according to the invention Synthetic resin coating with a structured surface, applied to a base, such as. B. paper, shows laminated or unlaminated aluminum foils or thin aluminum strips, from roll to roll; and

F i g. Figure 2 shows an enlarged cross-section through the finished product, with the various layers are not shown true to size for reasons of demonstration.

As can be seen from FIG. 1 results in a substrate 1 on the back with the help of a doctor blade, roller or Cylinder screen application device 2 coated.

The back coat is dried by a heating device 3 and by means of the second application device 4 the substrate is coated on the right side with a pigmented primer and through the Drying device 5 dried By the printing units 6 and 8, the first part of a pattern is on the Primer printed and then briefly dried through 7 and 9

The active base is then applied with the aid of a doctor blade, roller or cylinder screen application unit 10 and dried in the drying device 11. Then the transparent active base with the Barrier-forming substances that the printing varnish contains as a binder in the printing device 12 printed with the remaining part of the desired pattern, which will be used in the later course of the work This printing varnish should appear as a structured scar is briefly dried in the device 13 and then with the unsaturated resin mixture coated by the application device 14. In the vertical heater 15, this becomes unsaturated

Synthetic resin coating gels and after a short ventilation

polymerized, creating an immediate onset

Shrinking effect that causes colored structuring. After cooling down on a teflonized Cooling roller 16 is the active cover layer through the Device 17 printed or sprayed in a thin layer

(not shown), whereby after evaporation of the small amounts of solvent in the area 18 the Active cover layer itself is crosslinked for the most part in area 19 and its additives at the same time cause optimal hardening of the outermost, already structured UP resin boundary layer, resulting in one blockable and stackable coating, the surfaces of which are cooled by the cooling rollers 20 before the material is rolled up in the winder 21.

rails UCi AkiivucCksCi'iiOi'ii UV-miiiaiuren added have been and the recipe has been compiled accordingly, one of the Speed corresponding number of UV medium or high pressure lamps can be installed.

F i g. Figure 2 shows in a not to scale manner

a cross section through a according to the in F i g. I presented method manufactured product, wherein the Suostrat 1 is provided with a coating 2 on the back and coated with a primer 4. The first parts of a multicolored print design 6 and 8 lie in a plane through the transparent one Aktivgrund 10 covered. The lightest part of the multicolored Design 12 is located under the structured, transparent thermosetting synthetic resin coating 14, which is covered by the thin active cover layer 17.

The back coating applied with the device 2 can serve as a back adhesive layer, when the finished product is used for surface finishing of wood-based materials and the adhesive layer is compiled accordingly.

The adhesive layer on the back can be composed of a mixture of binders, for example, that from about 60 parts by weight of a vinyl chloride-acrylate copolymer with an OH content of 2%, 20 parts by weight of a reactive polyester plasticizer with an OH number of around 40 and 20 parts by weight of a polyfunctional isocyanate. The binders can in solvent mixtures, consisting of ketones, various esters and their Mixtures with aromatics, with a solid content

so from 30 to 50 percent by weight, can be solved. To the Pigmentation, most used pigments and extender pigments can be used.

To increase the solids content, organosols, consisting of a part of the o. A. Adhesive layer and a remaining portion of a pasteable PVC homopolymer with a mixture of a monomer Plasticizer and a reactive plasticizer are used as a fast-setting back coating will.

For the gelation of the low application quantities of 25 to 40 g / m ^2, those in FIG. 1 are sufficient. 1 with 3,5,7,9,11, 13,15 and 18 and 19 designated heating devices completely. The cross-linking of the layer also takes place for the most part during completion.

The primer, applied by the device 4, must have good adhesion to the substrate and the overall coating must have sufficient stability

lend wedge. A coating with a binder mixture consisting of nitrocellulose, alkyd resin (non-drying) and a polyfunctional aliphatic isocyanate produced excellent adhesion to paper and aluminum substrates. In addition, it shows good compatibility with the following printing varnishes to be applied and the active base. This layer, too, dries quickly and is for the most part cross-linked during the subsequent work steps. However, the person skilled in the art will also find many other ways of putting together appropriate primers. The application quantities should be between 5 and 10 g / m ² dry.

Print design parts are applied to the transparent or glazed pigmented active base with Printing varnishes whose solid substances are able to form a barrier for the active base peroxide, which is located under the printed swatches, and prevent the peroxide from immediately entering the Diffuse sections of the unsaturated resin coating with the printed swatches are directly related to the active ground.

The best result according to the invention is achieved with binders based on cellulose derivatives, such as hydroxyethyl cellulose, cellulose acetate, cellulose acetobutyrate. Nitrocellulose and its combinations, Polymethyl methacrylate and rosin esters, preferably with still reactive double bonds Rosin, vinyl chloride-acrylate copolymers with active hydroxyl groups, allyl-modified polymeric plasticizers with a hydroxyl number of 40 to 50, polyurethanes and polyacrylonitrile.

The following rosin esters are known: methyl esters of rosin, modified pentaesters and Pentaerithritol esters, hydrogenated methyl esters, maleic acid-modified esters and glycerol esters and pentaerythritol esters of polymerized rosin.

Surprisingly, a group of pigment preparations turned out to be particularly well suited for this Pigmentation of the printing varnishes used. The coated carrier material of this range of pigment preparations consists of a modified rosin ester with a small number of reactive ones Groups of rosin.

The carrier material is compatible with the above-mentioned binders of the pressure paint, and that The range of this pigment group enables any desired color tone; the pigment preparations can easily into the above Incorporate binding agent.

The peroxide from the active base diffuses immediately into the solvent-based printing varnishes and forms with the Binders that contain reactive double bonds, crosslinked, barrier-forming, patterned sections, the prevent the remainder of the peroxide under these printed swatches from immediately diffuse into the sections of the unsaturated resin coating that are in contact with the print pattern immediate contact. Since it hardly seems possible, the required amount of effective Substances in the active primer, barrier-forming print varnish and to calculate optimally stoichiometrically in advance in the curable UP synthetic resin coating, this is done To determine preliminary tests experimentally.

For active base solutions that are generally used as binders with nitrocellulose and compatible resins and contain plasticizers, free radical donors in the form of organic peroxides are used, the one rapid solubility in e.g. B. show esters. As such are known:

Cyclohexanone peroxide and mixtures of cyclohexan

nonperoxide with methyl ethyl ketone peroxide and methyl

isobutyl ketone peroxide.

A flame retardant ketone peroxide that has been launched on the market in recent years Acetylacetone peroxide with an active oxygen content of approx. 4%, showed surprisingly good results in the examples listed below, although it was for Active basic solutions has not been mentioned until now. The peroxide content in such active base solutions is generally 10-20%.

UP resins are mixed condensates of saturated and unsaturated dicarboxylic acids, e.g. B. maleic acid and Phthalic acid, with dihydric alcohols, e.g. B. 1.2-propylene glycol, which are dissolved in a polymerizable vinyl compound, usually styrene. As a result of the multitude of the resin settings and types available on the market were shown in the examples below all round resin based on isophthalic acid, with a shrinkage of 7 - 8%. The UP resins on Isophthalic acid base show high water resistance, good chemical resistance and heat resistance. One The finest tuning was achieved by adding an allyl-modified polyester with an acid number of 8 and a hydroxyl number of 40-50 and of a highly reactive diacrylic acid ester of bisphenol A with an acid number of 0.1 and a hydroxyl number of 16, mainly to be able to do the Shrinkage -% - age to vary.

At the same time, the paintability with the above crosslinkable thin-film lacquers through this Modifications improved what their surface quality in terms of their scratch, cigarette, stack and Brings blocking resistance very close to that of decorative laminates based on melamine. the UP resin mixtures were mixed with cobalt accelerators in styrene and paraffin in reactive solvents, the flow of the resin mixture was promoted, as was the non-stickiness of the Surface achieved in that the paraffin is known to have a very thin, air-tight seal on the resin surface The active solvent forms a layer so that inhibition by atmospheric oxygen cannot occur of the paraffin polymerize and are thus fully integrated into the polyester resin. as Fumed silicas were used as matting agents.

The composition of the active topcoat lacquers offers many possible variations, especially if you start from a binder such as vinyl chloride-acrylate copolymer, reactive due to its free OH groups and compatible with many lacquer raw materials, so that it is possible to produce solvent-resistant lacquers that dry quickly and with Isocyanates, melamine, urea and phenolic resins are crosslinkable. These active top coats, sprayed or rolled on in a thin layer, ie with a solid weight of 5-10 g / m ² , are block-resistant after the evaporation of the small amounts of solvent and after a short time continue to crosslink even in the roll. In addition, small amounts of additives that are normally used in vinyl chloride-acrylic-urethanes as light stabilizers and when processing two-component polyurethanes as crosslinking accelerators with a specific anti-sticking effect can surprisingly reduce the underlying, structured UP resin

Cure layer with the lowest residual monomer content and thus the stability of the completed Increase the shrinkage of the structured pattern.

It is also part of the state of the art that when curing UP resins by means of high-energy Radiation by adding a photosensitizer supports the photopolymerization in that one Peroxides and / or isocyanates are additionally added, so that the hardening accelerates and the adhesion increases adjacent layers is increased. There is thus a cost-saving option if you use the in A thin layer applied, for example, isoeyanate-containing active top layer, a photosensitizer clogs; the photosensitizers used with good lightfastness are of the benzoin ether type and benzil dimethyl ketal, which has recently gained importance.

The invention will now be described on the basis of exemplary embodiments explained in more detail.

Cut to size on paper or aluminum substrate strips made of paper or aluminum-laminated or non-laminated film webs suitable for coating the layers are applied one after the other using the so-called "Meyer rod", whereby optionally on a back coating and a printing of the first design part on the right-hand side Primer can be dispensed with. After each work step it must be dried briefly or in the case the use of the aforementioned plastisols or organosols are gelled at a temperature which depends on the PVC homo- or copolymers used and the solvating properties the mono- or polymer plasticizers used. The Meyer rod represents a rigid rod around which a thin metal wire of a certain thickness is wound and soldered to the rod at its ends. The stick will placed on the substrate strip, which is on a flat surface, and a small puddle of the Coating compounds to be examined are spread out in front of the rod. Then the rod is over the substrate drawn. It leaves a layer thickness on the substrate that depends on the diameter of the around the rod wound wire is dependent. With bars wrapped with wires of different thicknesses, different layer thicknesses can be applied.

Conventional laboratory drying ovens can be used for drying or gelling. Do you want to Use of organosols, plastisols or photopolymerizing coatings for high-energy radiation small laboratory installations available on the market can be used, preferably use a combined IR-UV radiation system, whereby the infrared part can optionally be regulated by means of a rheostat.

The sample strips are z. B. on a Teflon coated Conveyor belts guided through the laboratory installation at variable speeds and exposed to radiation sources, causing the coating layers be completely polymerized or crosslinked.

Applied with the Meyer stick in an »· application amount of 20-25 g / in ² dry substance.

Back coating compound:

Parts by weight

Vinyl chloride / acrylate copolymers ■ 185/15 (K value: about 40, OH content: 2%) 75

Unsaturated, aliphatic
Straight-chain polyester with terminal OH groups (hydroxyl value: 36 - 44, acid number: max. 3) 25

Fungicidal, epoxidized plasticizer (epoxy oxygen 5-6%) 5

Acrylamide resin (60% in xylene) 10

Aromatic diisocyanate, reaction product with a polyol (75%) 50 Waxy org. Amine accelerator with

λ _.:1.1-1 rr ~ i .. /irtfU.:—: _ -ri ι \ ι λ

rillllKlCUCCIICIW ^ I l / TUIg III IUlUKJt / II /

Color pigments and extender fillers 30 Butyl acetate 25 Methyl ethyl ketone 80 Methyl isobutyl ketone 40

Toluene 50

Total weight: 400 Solid content: approx. 45%

This rear-side coating has excellent adhesion to paper and aluminum substrates and makes it easier for the later processor to glue it to other documents, e.g. B. wood-based panels, due to the content of acrylate and acrylamide resin. After this back coating had dried, the top of the paper or aluminum substrate was coated with a primer in an application amount of approx. 5 to 10 g / m ² dry substance. The primer had the following composition:

40 Primer: Parts by weight Nitrocellulose '/ 4 sec. 80 toluene-moistened 45 Alkyd resin, non-drying, 50 60% in xylene Aliphatic. trifunctional isocyanate 50 (75% solution) 0.2 Zn octoate (8% Zn.) cn Maleinate resin solid JV (Ring and ball melting range: 10 155-175 ° C) 30th Pigments and fillers 75 Methyl ethyl ketone " 65 55 Methyl isobutyl ketone 25th toluene 15th Cellos olve acetate 400.2 Total weight: Solid content: approx. 40%

Example i

It became a mass of the following composition on the back of the present substrate with die strips, coated with this primer and briefly dried, can with the first part of a two-tone print design, z. B. after the rotogravure printing process printed with conventional printing inks and then briefly dried. It the active primer is then applied to the possibly printed primer in a weight ratio to the unsaturated resin coating of approx. 30:70. That

Total weight of the reactive system consisting au ": Active base and curable synthetic resin coating is preferably 30 to 50 g / m ² solid substance, so DAT the solid ratios of active base tu resin coating is preferably 10-20 g / m ² to 22 -46 g / m ² are should.

The basic active solution had the following composition:

Active basic solution, transparent:

10

15th

20th

25th

After this active base solution had dried briefly, the area was printed with the part of the design that Responsible for the structured design part in the gelled and polymerized transparent resin coating is.

The barrier-forming printing varnish had the following composition:

Parts by weight Nitrocellulose, moistened with butanol (1/2 sec.) 85 Peanut oil mod. Alkyd resin (60% in xylene) 60 Maleinate resin, solid 20th Dibutyl phthalate 9 Ethyl acetate 100 Butyl acetate Ί6 toluene 65 Buta. ~> \ 15th Total weight: 400 Solid content: approx. 30% To this solution were added: Acetylacetone peroxide (active oxygen: 4%) 40-50

Barrier-forming printing varnish: (black)

Parts by weight Ethyl cellulose (low viscosity) 25th Methyl ester of rosin 5 Fuel 200 Ethyl glycol 50 Reacts containing rosin. Pigment preparation 35 dissolved in toluene 85 Total weight: 400

35

40

45

Viscosity: 18-20 "measured in a 4 mm Ford cup.

This last part of the design can be printed using the gravure printing process, but preferably using the flexographic printing process because with the help of the last-mentioned printing process, the design parts make the active base more even cover and thereby the structuring in the resin coating is formed with sharper contours.

After a short drying period, the unsaturated, pre-accelerated synthetic resin coating was created with the help of the Meyer rod applied in the above ratio to the active base.

The composition of the coating mass was as follows:

Unsaturated resin solution: (transparent)

Parts by weight

Polyester resin, containing styrene, highly reactive (based on isophthalic acid, acid number: 15) 320 allyl modified. Polyester,
Hydroxyl number: 45 20

Monostyrene

Pyrogenic silica (matting) Cobalt accelerator 1% in styrene Paraffin in reactive solvent Total weight:

Parts by weight

10

22nd

20th

400

This unsaturated synthetic resin coating was able to gel and harden immediately at room temperature are observed and, with favorable nV application ratios of active primer to synthetic resin coating, a simultaneous structure formation in the surface, which with the last printed part of the design, z. B. in the form of a finest wood pore, matches.

After curing the resin coating at room temperature or at elevated temperatures of 80 ° to 100 ⁰ C! .. wnrHp ILIP AktivHprWschicht sprayed with a simple spray gun. The composition of such an active top layer was as follows:

65 active top layer: (transparent)

Vinyl chloride / acrylate copolymer, 2% OH groups

Unsaturated straight chain. aliph. polyester

(see above)

Fungicidal, epoxidized polym.

Plasticizers

Phosphite stabilizer

BaCd stabilizer

UV light protection agent

(Tetramethyl piperidine)

Waxy org. Amine accelerator, 10%

Aliphatic. -aromat. Diisocyanate,

60% solution

Silicone-free level and wetting agent butyl acetate

Methyl ethyl ketone

Methyl isobutyl ketone

Cellosolve acetate

toluene

Parts by weight

75

25th

0.5

1.2

0.3 20

50 3

30 60 50 40 30 Fumed silica (matting agent) 10

Total weight: 400.00
Solid content: approx. 38%

The active top layer sprayed on in a thin layer dried very quickly and crosslinked after 24 hours a block- and stack-resistant surface and polymerized activating by its accelerating amine additives the remaining monomers of the unsaturated synthetic resin coating that are in close contact with structured surface.

Example 2

This example was carried out in the same order as Example As a back coating a gelling and hardening, gui-adhesive organosol composition was used

Organosol coating on the back:

Parts by weight

Vinyl chloride / acrylate copolymer 85/15 (K value: 40, OH content 2%) 35

Parts by weight

PVC homopolymer, paste quality,
K value: 70 100

Unsaturated, aTipk, straight chain polyester
with terminal OH groups,
Hydroxyl number: 36-44 30

Fungicidal, epoxidized plasticizer 5
Gradketöger trimellitic acid ester 10

2 ^ 4-trimethyl-l _I 3-pentadiol diisobutyrate 20
Ba-Cd stabilizer 3

Org. Substance derivative with a
org. Metallverü. (10% solution in
Ethyl acetate / ethylene chloride) 20

Polyurethane containing stearyl groups,
10% solution 20

Methyl ethyl ketone 50 Ethyl acetate 30

Aromatic Hydrocarbon Thinner 52
Diisocyanate, reaction product from
Polvolen and one aromatic:
Diisocyanate (75% solution)

Total weight:
Solid content: approx. 50%

25th
400

Parts by weight Nitrocellulose, moistened with butanol, 'Λ sec. 95 Peanut oil mod. Alkyd resin (60% in xylene) 55 Maleinate resin, solid 20th Dibutyl phthalate 10 Dioctyl phthalate 5

Ethyl acetate
Butyl acetate
toluene
Butanol

Parts by weight

100

40

70

400

Ges.-Gewic '* »:
Solid content: approx. 32%
The following were added to this solution: cyclohexanone peroxide (active basic quality) (active oxygen content: approx. 11%) 80-100

This radical donor is not suitable for heat curing, so that the unsaturated synthetic resin coating be Room temperature should be gelled and cured. In such cases, the benefits of using it A thin layer of sprayed active top layer can be used to remove the residual moisture with the aid of UV rays to reduce the monomer content optimally and the outermost UP resin layer a good stacking and blocking wedge to lend at low surface temperatures.

The briefly dried active base layer was mii printed with the following barrier-forming printing varnish:

Barrier-forming printing varnish: (black)

The mass was prepared in such a way that the vinyl chloride-acrylate copolymer is in the listed ^ the correct solvents dissolved, the pasteable PVC homopolymer separately in the mono- and Polymer plasticizers pasted and both components intimately mixed with one another. So it came into being an organosol that can be pigmented in a desired shade.

Inexpensive pigments and extender pigments can be used for pigmenting, but should natural iron oxide pigments and chromates, which can disrupt the thermal stability, are avoided. That Isocyanate is expediently added after the organosol has been completed, shortly before use.

^{15-25 g / m 2} dry weight are sufficient for the back side, so that about 30-50 g / m ^{2 of} the organosol has to be applied to the back side of the substrate. The coating is dried at 60-80 ⁰ C is fast and can be gelled at 140-160 "C in 45 to 60 sec.. In a continuous production of this coated first backing durchkäuft the whole plant and thereby completely crosslinked. The added stearylgruppenhaltige Polyurethane gives the surface an excellent release effect, but the specified quantities should not be exceeded in order not to interfere with the subsequent adhesion to other substrates.

The subsequent priming can be done with the same primer as in Example 1 and with a conventional printing varnish can be printed. The active reason can have the following composition.

Active basic solution, transparent:

Parts by weight 60 Vinyl chloride-acrylate copolymer (K value: 40th OH content 2%) 50 Allyl mod. Polymer plasticizers (Acid number: 8, OH number: 40 - 50) 20th Butadiene acrylonitrile (MÄK-Iöülich) 10 MÄK 60 Butyl acetate 30th Ethyl glycol 60 TerL butanol 10 Pigment preparation containing rosin 100 toluene

Total weight: 400 Viscosity: 18-20 "measured in a Ford cup 4.

After a short drying period, the UP resin mixture was applied in the above ratio to the active base. Dii mixture had the following composition:

Unsaturated resin mixture:

Parts by weight

300 20

20th

Mod. UP resin, containing styrene,

highly active (isophthalic acid base) such as the diacrylic acid ester of bisphenol A.

Allyl mod. polyester

(Hydroxyl number 40-50)

Fumed silica (matting agent) 20 Monostyrene 10 Cobalt accelerator 1% in styrene 15 Paraffin in reactive solvents 10 Dimethylethanolamine 5 Total weight 400

After the application of this unsaturated resin mixture, the gelling of the coating started immediately and the structuring became apparent almost at the same time. B <moderately elevated temperature curing can be nigt beschlei, but a temperature of 60 ° bi 80 ⁰ C should not be exceeded. The remaining monomers in the outermost coating layer can be sprayed on in a thin layer (3 to 5 g / m ² dry) with the help of the following active top layer, with a photosensitizer

stabilizing additive, optimally polymerized and crosslinked.

Active top layer:

Parts by weight

Vinyl chloride / acrylate copolymer 85/15 75 Unlined, straight chain, aliphatic

Polymer soft 20 fungicidal, epoxidized

Polymer plasticizer 5 Ba-Cd stabilizer 2

Organic phosphite 0.5 Waxy org. Amine accelerator
(10% solution in toluene) with

Anti-stick effect 20 Fumed silica (matting agent) 12

Leveling and wetting agent (silicone-free) IJS Methyl ethyl ketone 80

Parts by weight toluene 20th Aromatic hydrocarbon Thinner (evaporation rate: 45) 100 Di-ai'hoxyacetone phenone 2 Benzophenone 1 Implementation product of a aliph. and aromatic diisocyanate in 60% butyl acetate solution 60 Total weight: 400 Solid content: approx. 36%

The viscosity is adjusted to atomization
After the solvent has evaporated, the coated substrate is finished under UV-energy-rich irradiation lamps in a final step, provided with a structured surface that is resistant to blocks and stacks.

1 sheet of drawings

Claims (6)

Patent claims: 1. A process for the production of a thermosetting synthetic resin coating with a structured surface, in particular made of transparent or translucent unsaturated polyester resin, in which the structured surface is produced by producing sections in the upper coating which cure at a slower rate by means of a layer applied under the upper coating as the remaining part of the top cover, so that shrinking occurs during curing and the sections which harden at a slower rate are pulled out in the direction of the shrunk part, so that the thickness of the cover is considerably reduced at the sections with the formation of depressions, characterized in this that for the continuous production of the synthetic resin coating on a carrier layer, radical polymerization initiators, sensitizers, accelerators, activators, promoters and / or crosslinking agents for curing the synthetic resin coating e nthaltende active primer layer applied, the active primer layer in sections with barrier-forming substances bands, which prevent the diffusion or migration of the proportion of the initiator, sensitizer, accelerator, activator, promoter and / or crosslinking agent located below these portions upwardly, and finally d ^v, \ resin coat brings up 2. The method according to claim 1, characterized in that that an accelerator-containing synthetic resin oil is applied. 3. The method according to claim I, characterized in that one is a folosensitizer containing active base layer and a synthetic resin coating containing an activator 4. The method according to claim 1, characterized in that one containing an activator Applying active base layer and a synthetic resin coating containing a photosensitizer 5. The method according to any one of the preceding claims, characterized in that one before the application of the active base layer, the carrier substrate optionally only with a primer and provides a print design or a part thereof. 6. The method according to any one of the preceding claims, characterized in that the barrier-forming substances in the form of an independent single-color print pattern or in the form applies part of a multicolored print pattern.