DE102004016037A1 - Method for the permanent abrasion-resistant colored inscription and/or marking of plastics comprises preventing bleeding and/or blooming of the dye and/or absorber in the plastic during sealing of inscribed sites with a transparent polymer - Google Patents

Abstract

Method for the permanent abrasion-resistant colored inscription and/or marking of plastics comprises preventing bleeding and/or blooming of the dye and/or absorber in the plastic during sealing of inscribed sites with a transparent polymer. An independent claim is also included for a plastic with a sealed marking and/or inscription.

Description

The The present invention relates to the sealing of plastic labels, by means of laser on the plastic surface, preferably indirectly, have been generated.

With Help of laser beams of different wavelength it is possible materials and production goods permanently mark and label.

in the Another is the term "labeling" any type of Labeling by the laser, i. Labeling, marking, coding, etc., to be understood.

Under "colored Laser lettering " the labeling of plastics using all the colorful and achromatic pigments or dyes (all colors including black, white and all shades of gray) Understood.

• 1. auf das Material selbst (intrinsische Reaktion) oder
• 2. auf ein Beschriftungsmedium, welches von außen auf das zu beschriftende Material übertragen wird (indirekte Markierung).

The markings and / or inscriptions are made by the action of the laser energy

• 1. on the material itself (intrinsic reaction) or
• 2. on a labeling medium, which is transmitted from the outside to the material to be labeled (indirect marking).

So react with marking method 1) for example, metals on laser irradiation with different tempering colors, woods are irradiated to the Make dark (charring) and plastics, such as. As PVC show depending on plastic coloring light or dark discoloration (Foaming, Carbonation).

frequently reinforced or these effects are initiated in plastics by the addition of laser-sensitive pigments. The disadvantages are usually in that only the "colors" are white and black or different gray and bleaching stages can be achieved, and that the entire plastic material in the masterbatch the laser-sensitive Pigments must be added.

Meets in marking method 2) a laser beam of suitable energy and wavelength (For example, IR laser) on a labeling medium and is this in contact with the material to be labeled, the labeling medium transferred to the material and fixed there. Indirectly, materials can be used with suitable ones colorful and achromatic pigment or Dye mixtures, suspensions, pastes or laser films or tapes label. In this way a colored and black and white lettering is possible. The actually needed for labeling Amount of laser pigment is much lower than z. B. the masterbatch additive (Labeling method 1).

the Persons skilled in the art are generally familiar with marking media made of glass frits or glass frit precursors with laser energy absorbers, which - depending on desired Color - with inorganic and organic pigments, metal oxides, organometallic Substances or metal powders are added. Such methods be z. As described in WO 99/16625, U.S. Pat. 6,238,847, U.S. Pat. 6,313,436 and WO 99/25562.

After applying the pigment and / or dye mixtures directly to the medium to be labeled, for. B. by spraying, brushing, sprinkling, electrostatic charging, etc. or on carrier substrates such as tapes, films or the like, with the required laser energy (1-30 W output power in CW operation) or laser energy density (in the pulsed mode 100 W / cm ² -3 GW / cm ² ) irradiated and labeled. In this way, glass, ceramics, metal, stone, plastics and composites can be labeled. Such labeling methods are known, for example, from WO 03/035411, WO03 / 080334 and WO03 / 080335.

In the publications EP 1279517 A1 and DE 19942316 A1 Laser-sensitive mixtures of colorants / absorbers or glass pigments / plastic granules are described specifically for the colored laser marking and marking of plastics.

One significant disadvantage in the indirect generated in these methods Laser inscription of plastics is the locally very high pigment or dye concentration at the labeling points, which is often leads to smeared, blurry labels that bloom even later or can bleed out. This occurs especially when using organic pigments or dyes on.

While at the conventional plastic coloring with maximum pigment concentrations of ≥ 0.5 % for organic Pigments and ≥ 2 % for inorganic Pigments is worked, the pigment concentrations are at the e.g. according to WO 99/16625 laser-inscribed plastic sites well over 20%.

This overpigmentation leads - in dependence from the labeled plastic and the later use temperature - for migration the pigments or dyes to the plastic surface, for so-called efflorescence.

Become the captions brought into contact with other materials and there will be a transition the excess pigments or dyes in these materials, this is called bleeding.

This overpigmentation makes extra Post-cleaning and drying steps required, in particular for one inline production process with the product labeling as the last process step technological undesirable or unacceptable.

Of another bleeds or blooms the label turns off or fades in use, for example by environmental influences, Etc.

For certain Applications, such as labeling of food commodities, packaging for medicines, Children's toys, medical devices, etc., can be so bleeding or efflorescent Do not use labels at all.

task The present invention therefore is a non-efflorescent, non-bleeding Laser marking of plastics with high edge sharpness and high resistance to environmental influences to achieve, with the laser marking on the plastic surface, preferably indirectly, is generated.

Surprisingly it was found that the blooming or bleeding of the laser-marked in color with a laser plastics by sealing the labeled areas during the labeling process is prevented. The sealing is done with the help of transparent Layers of polymers, preferably glass transition temperatures ≥ 150 ° C, in particular ≥ 140 ° C, and completely particularly preferably ≥ 125 ° C, have.

object The invention is a method for permanent and abrasion resistant colored lettering of plastics, characterized that the bleeding or blooming of colorants and / or absorbers at the inscribed points in the plastic prevented by the places marked by a laser during the labeling process or immediately thereafter sealed with a transparent polymer layer.

• – Verschmieren und/oder späteres Ausbluten/Ausblühen der Pigmente oder Farbstoffe wird verhindert
• – unerwünschte Reinigungsschritte nach dem eigentlichen Beschriftungsprozess werden eingespart
• – die Farbechtheit der Beschriftung im späteren Gebrauch wird garantiert.

Compared with the prior art, the method according to the invention is characterized by the following features:

• - Smearing and / or later bleeding / blooming of the pigments or dyes is prevented
• - Unwanted cleaning steps after the actual labeling process can be saved
• - The color fastness of the label in later use is guaranteed.

The polymer layer for the sealing can be applied in a one-step process together with the laser inscription or in a two-step process to the inscription made in the first step. Layer systems according to the 1 - 4 proved.

The labeling of the plastic with a laser is preferably carried out by indirect labeling, for example as in WO 99/16625 or in the unpublished DE 10352857 is described. The plastics are labeled in color by the labeling medium is introduced by means of laser energy in the plastic substrate. If necessary, the labeling medium separates from the carrier film and then combines permanently with the likewise heated and thus locally softened plastic surface.

In 1 the 1-step process is shown schematically in the inventive method. Here, the layer system consists of a laser light-permeable and durable carrier layer ( 1 ei ner laser-sensitive energy absorber layer ( 2 ), a release layer ( 3 ), a sealing layer ( 4 ) and finally a labeling medium ( 5 ), the latter containing pigments and / or dyes. This layer system is brought with the Beschriftungsmediumseite in close contact with the plastic to be inscribed.

With a suitable laser, the inscription of a plastic with an overlying seal is generated in this one-step process. The necessary energy is transferred via the energy absorber layer ( 2 ) on the release layer ( 3 ), which softens and thus the sealing layer ( 4 ) and the labeling medium ( 5 ) transfers to the plastic. The laser energy must be chosen so that the plastic also softens at the inscription points and forms a firm connection with the sealing layer.

In the 2-step process, the labeling process is separate from the subsequent sealing. In step 1 the label is created. This can be done with layer structures as in the 2 and 3 shown, done.

On a laser light-permeable and resistant carrier foil ( 1 ) are either the energy absorber layer ( 2 ) and the labeling medium ( 5 ) as separate layers ( 2 ) or as a layer ( 6 ) consisting of a mixture of labeling medium and energy absorber ( 2 ) ( 3 ) applied.

With a suitable laser, the necessary energy through the energy absorber layer ( 2 ) on the labeling medium ( 5 ) and transferred to the plastic or just above the layer ( 6 ) transferred to the plastic. The labeling medium ( 5 ) goes over to the softened plastic and leads to a lettering of the plastic.

In the second step, the seal with a layer structure ( 4 ) made of a laser light-permeable and durable carrier layer ( 1 ), a laser-sensitive energy absorber layer ( 2 ), a release layer ( 3 ) and a sealing layer ( 4 ) generated.

With a suitable laser, the necessary energy through the energy absorber layer ( 2 ) on the release layer ( 3 ), which softens and thus the sealing layer ( 4 ) transfers to the plastic. The laser energy must be chosen so that the plastic softens again at the labeling points and forms a firm connection with the sealing layer.

As materials for the carrier layer ( 1 ) are all materials that are ideally transparent and / or translucent in the specified wavelength range for the laser light and are not damaged or destroyed by the interaction with the laser light.

It suitable materials are e.g. Glass and plastics, ideally in the form of films, tapes or plates are used and preferably Layer thicknesses of 5-250 microns, in particular 10-150 μm and whole more preferably 15-75 microns.

suitable Plastics are preferably thermoplastics. Especially consist of polyesters, polycarbonates, polyimides, Polyacetals, polyethylene, polypropylene, polyamides, polyesters, Polyesterester, Polyetherester, Polyphenylenether, Polybutylenenterephthalat, Polymethyl methacrylate, polyvinyl acetal, polyvinyl chloride, polystyrene, Acrylonitrile Butadiene Styrene (ABS), Acrylonitrile Styrene Acrylic Ester (ASA), Polyethersulfones and polyether ketones and their copolymers and / or mixture.

From The plastics mentioned are particularly preferably polyesters, Polycarbonates and polyimides.

When Energy absorbers can All materials used in the specified wavelength range sufficiently absorb the laser light energy and into heat energy convert.

The energy absorbers suitable for the labeling are preferably based on carbon, carbon black, anthracene, pentaerythritol, phosphates such as copper hydroxide phosphates, sulfides such as molybdenum disulfide, oxides such as antimony (III) oxide, Fe ₂ O ₃ and TiO ₂ , bismuth oxychloride, platy , in particular transparent or semitransparent substrates of z. Example, phyllosilicates, such as synthetic or natural mica, talc, kaolin, glass slides, SiO ₂ platelets or synthetic carrier-free platelets. Furthermore, platelet-shaped metal oxides, such as. Example, platelet-shaped iron oxide, alumina, Ti tan dioxide, silicon dioxide, LCP's (liquid crystal polymers), holographic pigments, conductive pigments or coated graphite platelets into consideration.

When platelet-shaped pigments can Also metal powder can be used, the uncoated or too covered with one or more metal oxide layers; prefers are z. B. Al, Cu, Cr, Fe, Au, Ag and steel flakes. Should be susceptible to corrosion metal plates such as B. Al, Fe or steel plates uncoated are used, they are preferably with a protective Coated polymer layer.

Next platelet-shaped substrates can also spherical Pigments are used, for. B. from Al, Cu, Cr, Fe, Au, Ag and / or Fe.

Particularly preferred substrates are mica flakes coated with one or more metal oxides. Both colorless high-index metal oxides, in particular titanium dioxide, antimony (III) oxide, zinc oxide, tin oxide and / or zirconium dioxide are used as metal oxides, as well as colored metal oxides, such as. For example, chromium oxide, nickel oxide, copper oxide, cobalt oxide and iron oxide in particular (Fe ₂ O ₃ , Fe ₃ O ₄ ). It is particularly preferred to use antimony (III) oxide alone or in combination with tin oxide as the energy absorber.

These substrates are known and mostly commercially available, for. B. under the trade name Iriodin ^® Lazerflair Fa. Merck KGaA, and / or can be prepared by standard methods known in the art. Pigments based on transparent or semi-transparent platelet-shaped substrates are e.g. As described in German patents and patent applications 14 67 468, 19 59 998, 20 09 566, 22 14 454, 22 15 191, 22 44 298, 23 13 331, 25 22 572, 31 37 808, 31 37 809, 31st 51 343, 31 51 354, 31 51 355, 32 11 602, 32 35 017, 38 42 330, 44 41 223.

Coated SiO ₂ platelets are z. B. known from WO 93/08237 (wet-chemical coating) and the DE-OS 196 14 637 (CVD method).

Multilayered pigments based on phyllosilicates are known, for example, from German Offenlegungsschriften DE 196 18 569 . DE 196 38 708 . DE 197 07 806 and DE 198 03 550 known. Particularly suitable are multilayer pigments which have the following structure: Mica + TiO ₂ + SiO ₂ + TiO ₂ Mica + TiO ₂ + SiO ₂ + TiO ₂ / Fe ₂ O ₃ Mica + TiO ₂ + SiO ₂ + (Sn, Sb) O ₂ SiO ₂ platelets + TiO ₂ + SiO ₂ + TiO ₂

Particularly preferred laser light absorbing substances are anthracene, pentaerythritol, copper hydroxide phosphates, molybdenum disulfide, antimony (III) oxide, bismuth oxychloride, carbon, antimony, Sn (Sb) O ₂ , TiO ₂ , silicates, SiO ₂ flakes, metal oxides coated mica and / or SiO _{2 2} platelets, conductive pigments, sulfides, phosphates, BiOCl, or mixtures thereof.

Of the Energy absorber can also be a mixture of two or more components be.

The labeling medium ( 5 ) can be applied as a paste or as a layer with carrier. The labeling medium consists essentially of colorant, binder and optionally polymer component, preferably in the form of particles, additives and adhesive.

For the label Both organic and inorganic colorants come into question. Suitable are all the colorants known to those skilled in the art do not decompose the laser irradiation. The colorant may be is also a mixture of two or more substances. The proportion of colorants in the labeling medium is preferably 0.1-30 % By weight, in particular 0.2-20 % By weight and very particularly preferably 0.5-10% by weight, based on the total mass the marking medium (polymer component + colorant + binder + Solvent).

Suitable colorants are all organic and inorganic dyes and pigments known to the person skilled in the art. Particularly suitable azo pigments and dyes, such as mono-, Diazopig mente and dyes, polycyclic pigments and dyes such. As perinones, perylenes, anthraquinones, flavanthrones, isoindolinones, pyranthrones, anthrapyrimidines, quinacridones, thioindigo, dioxazines, indanthronones, diketo-pyrolo-pyrroles, Chinonphthalone, metal-complexing pigments and dyes such. As phthalocyanines, azo, azomethine, dioxime, isoindolinone complexes, metal pigments, oxide and oxide hydroxide pigments, oxide mixed phase pigments, metal salt pigments, such as. As chromate, chromate-molybdate mixed phase pigments, carbonate pigments, sulfide and sulfide selenium pigments, complex salt pigments and silicate pigments.

From the colorants mentioned are particularly preferably copper phthalocyanines, Dioxazines, anthraquinones, monoazo and diazo pigments, diketopyrolopyrrole, polycyclic pigments, anthrapyrimidines, quinacridones, quinaphthalenes, Perinones, perylene, acridines, azo dyes, phthalocyanines, xanthene, Phenazines, colored oxide and oxide hydroxide pigments, oxide mixed phase pigments, Sulfide and sulfide selenium pigments, carbonate pigments, chromate, chromate-molybdate mixed-phase pigments, Complex salt pigments and silicate pigments.

Preferably, the ratio absorber / colorant for the 2-step process ( 3 ) 10: 1-1: 10, especially 5: 1-1: 5, most preferably 4: 1-1: 4.

to Improvement of the adhesion may be the labeling medium a polymer component be added. Preferably, it consists of low-melting Polymers such as e.g. Polyesters, polycarbonates, polyolefins, polystyrene, Polyimides, polyamides, polyacetals and copolymers of the above Polymers, and terpolymers of vinyl chloride, dicarboxylic esters and vinyl acetate or hydroxyl acrylate or mixtures thereof. The polymer component can be solved in the labeling medium or unresolved exist as a fine powder. The particle sizes are preferably 10 nm-100 μm, in particular 100 nm-50 μm and completely particularly preferably 500 nm-5 μm. It can also a mixture of different polymer particles are used, where both the particle sizes as can also distinguish the chemical composition.

The Contains labeling medium preferably 10-50 % By weight, especially 15-40 % By weight, and most preferably 20-35% by weight of polymers on the total mass of the color paste with polymer component + colorant + Binder + solvent.

Preferably is the relationship Polymer component / colorant 200: 1 - 1: 1, in particular 100: 1 - 2 : 1, most preferably 70: 1 - 3: 1.

When contains further component the labeling medium is a binder.

The Binder allows a homogeneous application of the labeling layer on materials such as. Glass and plastics, ideally in the form of films, Tapes or plates are present.

All binders known to the person skilled in the art are suitable, in particular cellulose, Cellulose derivatives, such as. Cellulose nitrate, cellulose acetate, hydrolyzed / acetalized Polyvinyl alcohols, polyvinyl pyrrolidones, polyacrylates as well as copolymers of ethylene / ethylene acrylate, polyvinyl butyrals, epoxy resins, polyesters, Polyisobutylene, polyamides.

The optionally added adhesive allows for a close contact of the marking medium ( 5 ) to the plastic and creates a firm connection between labeling medium ( 5 ) and sealing ( 4 ). The adhesive preferably consists of polymers and copolymers of polyvinyl acetates, methyl, ethyl, butyl methacrylates, unsaturated polyester resins or mixtures thereof.

The separating layer ( 3 ) is preferably formed from ester wax or polyvinyl alcohol. The release layer must release the sealant layer from the tape easily and completely (without damage) when heated.

The sealing layer ( 4 ) may consist of polymers, preferably with glass transition temperatures ≥ 100 ° C, in particular of polymers of styrene, methyl methacrylate or hydroxy-functional acrylates, PE waxes and dispersions, polyvinyl fluoride and nitrocellulose as a binder.

The layer thicknesses of the multilayer systems are preferably:

The Layer thicknesses of the multilayer systems should have a total thickness of 30-350 microns, preferably 50-250 microns and in particular of 70-100 μm, because with too thick layer systems an edge sharp marking and full Seal of the mark is not guaranteed.

The described multilayer systems are placed on the plastic and with the necessary contact pressure (mechanically or by added activatable Adhesive component) in close contact with the areas to be labeled brought. The inscription is done with a suitable laser in the Beam deflection method.

ever according to plastic type can For labeling all known in the art laser can be used. The laser parameters depend on the particular application and easily determined by the expert.

The inscription with the laser takes place in such a way that the specimen is brought into the beam path of a laser, preferably an Nd: YAG or Nd: YVO ₄ laser. However, even with other conventional types of lasers having a wavelength in a high absorption region of the laser light absorbing substance used, the desired results are to be obtained. The mark obtained is determined by the irradiation time (or pulse number in pulse lasers) and the irradiation power of the laser and the plastic system used. The power of the laser used depends on the particular application and can be determined in individual cases by the skilled person readily.

The laser used generally has a wavelength in the range of 157 nm to 10.6 μm, preferably in the range of 532 nm to 10.6 μm. For example, mention may be made here of CO ₂ lasers (10.6 μm) and Nd: YAG lasers (1064 or 532 nm) or pulsed UV lasers. The excimer lasers have the following wavelengths: F ₂ excimer laser (157 nm), ArF excimer laser (193 nm), KrCl excimer laser (222 nm), KrF excimer laser (248 nm), XeCl excimer laser (308 nm ), XeF excimer laser (351 nm), frequency multiplied Nd: YAG lasers with wavelengths of 355 nm (frequency tripled) or 265 nm (frequency quadrupled). Particular preference is given to using Nd: YAG lasers (1064 or 532 nm) and CO ₂ lasers. The energy densities of the lasers used are generally in the range from 0.3 mJ / cm ² to 50 J / cm ² , preferably 0.3 mJ / cm ² to 10 J / cm ² .

For labeling, an Nd: YAG laser, Nd-VO ₄ or CO ₂ laser in different laser wavelengths, 1064 nm, 532 nm or 808-980 nm, is preferably used. The marking is possible both in continuous cw mode (continuous wave) and in pulse mode. The suitable power spectrum of the marking laser comprises 2 to 100 watts, the pulse frequency is preferably in the range of 1 to 100 Hz.

Appropriate Lasers in the process of the invention can be used are commercially available.

The Labels according to the invention of plastics can be everywhere Find application, where previously plastic with printing, embossing or Engraving were labeled or anywhere, where ever no or no colorfast and permanent label / marking or only a label / marking using laser-sensitive Pigments in the plastic itself possible was. This concerns linear or thermolabelled cross-linked plastics, e.g. Polyolefins, vinyl polymers, polyamides, polyesters, polyacetals, Polycarbonates, z.T. also polyurethanes and ionomers.

The Advantages of the invention Beschriftungsart are the color fastness, permanence and flexibility / individuality, i. Marking is done without mask, cliché or stamp specification.

• • in der Verpackungsindustrie (Chargennummer, Haltbarkeitsdaten, Hinweise)
• • im Sicherheitsbereich (fälschungssichere Codierung und Kennzeichnung)
• • in der Kraftfahrzeug- und Flugzeugindustrie (Kabel, Stecker, Schalter, Behälter, Funktionsteile, Schläuche, Deckel, Griffe, Hebel, etc.)
• • in der Medizintechnik (Geräte, Instrumente, Implantate)
• • in der Landwirtschaft (Tierohrmarkenkennzeichnung)
• • in der Elektrotechnik/Elektronik (Kabel, Stecker, Schalter, Funktionsteile, Typen-, Leistungsschilder)
• • Dekorativer Bereich (Logos, Typenbezeichnung für Geräte aller Art, Behälter, Spielzeug, Werkzeug, individuelle Markierungen)

markiert und/oder beschriftet werden.It can be plastics of any kind and shape, eg

• • in the packaging industry (batch number, expiry dates, notes)
• • in the security area (forgery-proof coding and labeling)
• • in the automotive and aircraft industry (cables, plugs, switches, containers, functional parts, hoses, covers, handles, levers, etc.)
• • in medical technology (devices, instruments, implants)
• • in agriculture (animal earmarking)
• • in electrical engineering / electronics (cables, plugs, switches, functional parts, type and rating plates)
• • Decorative area (logos, type designation for all types of equipment, containers, toys, tools, individual markings)

be marked and / or labeled.

object The invention also relates to plastics which are obtained by the process according to the invention marked in color or labeled and their mark sealed has been.

The The following examples are intended to illustrate the invention without, however, limiting it. The percentages given are percent by weight.

embodiments

Depending on the layer thickness, the individual layer systems are applied to the polyester carrier film or the preceding layer using a doctor blade or a gravure roller or by screen printing and dried. Example 1: Production of an Energy Absorber Layer (2) 18.5 g ethyl acetate 1.5 g nitrocellulose 2.0 g Sn (Sb) O ₂ (d ₅₀ value <1.1 μm) (Du Pont)

Nitrocellulose is dissolved in the initially introduced solvent ethyl acetate and stirred well (Ultrathurax, 2000 rpm). Subsequently, the energy absorber Sb-doped SnO _{2 is} stirred in and a homogeneous paste is produced. The amount of energy absorber is dependent on the energy absorption of the colorant and the plastic to be marked and set to this. Example 2: Production of an Energy Absorber Layer (2) 18.5 g ethyl acetate 1.5 g nitrocellulose 2.0 g Gas black (special black 6 from Degussa)

The processing is carried out analogously to Example 1. As the absorber gas black is used. Example 3 Production of a Release Layer (3) 19.9 g toluene 0.1 g Esterwachs

The PE wax is dissolved in toluene and stirred well. Example 4: Preparation of a sealing layer (4) 8.0 g methyl ethyl ketone 4.6 g toluene 2.0 g cyclohexanone 3.9 g PMMA ( _Tg : 122 ° C) (Degussa) 1.5 g PE wax

The PE wax and PMMA are dissolved in the solvent mixture and homoge with a dissolver nized. Example 5: Preparation of a sealing layer (4) 8.0 g xylene 4.0 g polystyrene 2.0 g PE wax

The PE wax and polystyrene are dissolved in xylene and homogenized with a dissolver. Example 6: Preparation of a sealing layer (4) 40.0 g n-butyl acetate 10.0 g foamed polystyrene 0.5 g ethylcellulose

The ethylcellulose and the polystyrene are dissolved in n-butyl acetate and homogenized with a dissolver. Example 7 Production of a Polymer Particle-Containing Marking Medium (5) 20.0 g ethyl acetate 2.0 g nitrocellulose 6.0 g Polypropylene powder (d ₅₀ <50 mm) 2.0 g Cu phthalocyanine

The Nitrocellulose is dissolved in the initially introduced solvent ethyl acetate and good stirred. Subsequently, will the polypropylene powder and the colorant copper phthalocyanine stirred in and made a homogeneous paste. If necessary will improve the paste homogeneity a 3-roll chair used.

The paste is z. B. a squeegee on polyester films and dried. Example 8 Preparation of a Polymer Particle-Containing Marking Medium (5) 25.0 g methyl ethyl ketone 34.0 g toluene 12.0 g PVC / PVAc copolymer 16.0 g polyurethane 0.5 g titanium oxide

The processing is carried out analogously to Example 7. As the colorant titanium dioxide is used. Example 9 Production of a Polymer Particle-Containing Marking Medium (5) 35.0 g n-butyl acetate 6.0 g foamed polystyrene 2.0 g nitrocellulose 2.0 g Cu phthalocyanine

The processing is carried out analogously to Example 7. The colorant used is Cu phthalocyanine. Example 10 Production of a Layer (6) from Labeling Medium (5) and Energy Absorber (2) 20.0 g ethyl acetate 2.0 g nitrocellulose 6.0 g Irgazin Red 1.2 g Sn (Sb) O ₂

The processing is carried out analogously to Example 7. The colorant used is irgazine red and as absorber Sn (Sb) O ₂ .

Example 11: Marking Trials and Results

Example 12: Comparison of markings with and without seal with regard to the effect on bleeding / blooming

Claims (10)

Process for the permanent and abrasion-resistant colored lettering and / or marking of plastics, characterized in that the bleeding or blooming of the colorants and / or absorbers in the plastic is prevented by placing the laser-inscribed areas during the inscription process or immediately thereafter with a sealed transparent polymer layer. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 1, characterized in that the polymer has a glass transition temperature of ≥ 150 ° C. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 1 or 2, characterized in that the sealing layer from the polymers of styrene, of methyl methacrylate or hydroxy-functional Acrylates, polyvinyl fluoride exists. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to one of claims 1 to 3, characterized in that the polymer layer thicknesses of 1-10 μm. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to one of claims 1 to 4, characterized in that the marking by a indirect labeling process takes place. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 5, characterized in that the label with a laser and sealing done in one step. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 5, characterized in that in a two-stage process only the caption with a laser and immediately afterwards in a second step, the sealing of the labeled bodies takes place. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 5 or 6, characterized in that one uses a layer system, which consists of at least five superimposed Layers, wherein as the first layer, a laser light-transmissive carrier film serves, on which the laser light-sensitive energy absorber layer applied is, then the release layer and the sealant layer and as the last layer the marking medium containing colorant and possibly polymer particles, wherein the labeling medium under the action of laser light at the label / marking introduced into the plastic surface becomes. Process for permanent and abrasion resistant colored Labeling and / or marking of plastics according to claim 5 or 7, characterized in that for the lettering a layer system consisting of a laser light-transmissive carrier foil and the energy absorber layer and the labeling medium as separate layers or a layer system consisting of carrier foil and a layer consisting of a mixture of labeling medium and energy absorber used, marked with a laser, the Labeling medium on the softened plastic passes and in the second step, the seal is carried out with a layer system consisting of a laser light-transmissive carrier layer, a laser-sensitive absorber layer, a release layer and a Sealing layer and irradiated with a laser, with the necessary Energy over the energy absorber layer is transferred to the release layer, which softens and thus transfers the sealant layer to the plastic. Plastics obtained by the process according to a the claims 1 to 9 have a sealed mark and / or label.