DE102018120815A1 - Method for producing a laser-modified decal or heat transfer - Google Patents

Abstract

A method of making a decal comprising the following steps
a) providing a multilayer arrangement comprising at least one carrier film and a paint and / or ink layer with laser-reactive pigments;
b) providing the paint and / or ink layer with a lettering and / or a drawing by a laser beam of a laser and application on a substrate before or after the aforementioned laser irradiation; and
c) removing the carrier film;
wherein the laser beam is passed through the carrier film on the paint and / or ink layer and / or from one of the carrier film (2) opposite side on the paint and / or ink layer (3, 4) is passed;
as well as a decal.

Description

The present invention relates to a method for producing laser-modified decal or heat transfer.

Various methods for applying a drawing or lettering to a substrate are known from the prior art.

The DE 10 20014 115 910 describes the labeling of a label. In contrast to a decal, no layers are removed from the labeled surface at the end of the process. It is therefore another application with different procedural requirements.

From the DE 94 29 174 U1 a method for printing printed conductors on a laminate of a rigid printed circuit board is known. Here, laser light is passed through a translucent film and blackens an underlying substrate.

The WO 2017/108623 A1 discloses an adhesive film in which laser-reactive pigments can be arranged. However, an indication of a production process using these special laser-reactive pigments is not known from this document.

Based on the aforementioned prior art, it is the object of the present invention to provide a method for producing a decal, with which decals with high quality and with little time can be produced, but still individualized as in digital printing preferably individually for each decal or heat transfer individually can be.

The present invention solves this problem by a method having the features of claim 1.

1. a) Bereitstellen eines mehrschichtig aufgebauten Abziehbildes oder Hitzetransfers als eine Anordnung umfassend zumindest eine Trägerfolie und eine Lack- und/oder Farbschicht mit laserreaktiven Pigmente;

A method according to the invention for producing a decal or heat transfer comprises the following steps:

1. a) providing a multi-layered decal or heat transfer as an arrangement comprising at least one carrier film and a paint and / or ink layer with laser-reactive pigments;

The multilayer arrangement may comprise further layers.

Thus, it is advantageously possible that not only a color and / or lacquer layer but also a plurality of lacquer and / or color layers can be provided.

It is also advantageously possible for these multiple layers to comprise pigments, in particular laser-active pigments. Since the layers can reduce the intensity of the incident laser light, a layered staining can be carried out, wherein the pigments in the subsurface layers discolor in a smaller number, so that the coloring is less intense, even if the same pigments are used.

• b) Versehen der Lack- und/oder Farbschicht mit einer Beschriftung und/oder einer Zeichnung durch einen Laserstrahl eines Lasers und Applikation auf einem Untergrund vor oder nach der vorgenannten Laserbestrahlung;

It is also advantageously possible to use pigments with different chemical composition and thus different color change in different color and / or lacquer layers. As a result, a multi-color can be achieved.

• b) providing the paint and / or ink layer with a lettering and / or a drawing by a laser beam of a laser and application on a substrate before or after the aforementioned laser irradiation;

In this process step, a lettering or a drawing, ie a pattern of lines and lines, are applied by the laser. Also symbols e.g. Pictograms can be reproduced as a drawing. The lettering includes letters u.a. also numbers.

• c) Entfernen der Trägerfolie;

Before or after providing a label or drawing, the application can be carried out on a substrate. Here, advantageously, an adhesive layer offers, which allows a fixation on the ground.

• c) removing the carrier film;

For a decal typical now the carrier film is removed, so that the made by laser decal remains with the or the corresponding color and / or lacquer layer on the substrate to be applied.

A special feature of the present method is that the laser beam is passed through the carrier film on the paint and / or ink layer.
As an alternative to the conduction of the laser beam through the carrier, it is possible to direct the laser beam to the printed side of the transfer and therefore to individualize it from the back side, ie from the side opposite the carrier foil. This can be done by Direktbestahlung the paint and / or ink layer or preferably by irradiation through an adhesive layer.

As a result, for example, an on-site prefabrication of the decal take place, which at the application, typical of a decal or heat transfer, only from the Carrier film and, if necessary, must be separated from an optional backing paper. Alternatively, customers will be able to carry out customization by laser directly on site. As a result, secrecy, automation with software systems and / or individualization at the latest possible time for a more flexible production of the customer, can be maintained.

The laser-modified decal and / or the laser-modified heat transfer is flexible in contrast to a printed circuit board and pursues a decorative goal, whereas tracks are a purely technical implementation. The lettering of the decal or heat transfer is characterized by the fact that it can also be done before applying the target substrate (application background).

Advantages of this procedure are u.a. an ink-free printing process, a high resolution design of a label and / or a drawing and a possible uncomplicated transport, storage and application of the decal to a substrate.

The method can thus combine the advantages of a highly productive uniform printing process such as screen printing with the advantages of individualization such as digital printing by the possibility of individualization by means of laser.

Advantageous embodiments of the method according to the invention are the subject of the dependent claims.

By the laser beam, a color change of the pigments can take place, wherein the number of excited pigments and thus the intensity of the color change by the laser adjustment, in particular the intensity of the laser beam and the wavelength, are adjustable. This has the advantage that a light / dark graduation can be achieved analogous to a gray scale print.

The production of the decal by color change of the laser-reactive pigments can in particular be ink-free, so that discoloration to other printing media is excluded. At the same time the printed image is protected.

For easy and residue-free detachment of the release layer from the adjacent paint or ink layer, the multi-layer decal or heat transfer as a multi-layered arrangement between the support film and the paint and / or ink layer, a release layer, preferably on silicone and / or wax base have ,

For optimum irradiation of the carrier film by the laser while at the same time having sufficient tear resistance, the carrier film during stripping is a thickness between 75 and 130 μm particularly advantageous.

The laser used can advantageously be operated in the present process up to a power of up to 20 W, so that the matrix material of the paint and / or lacquer layer is not excessively damaged or even thermally decomposed upon irradiation of the pigments.

For advantageous fixing on a substrate, the paint and / or ink layer can advantageously have an adhesive layer on an opposite side of the carrier film. The carrier film forms starting from the viewing direction of a viewer (arrow A ) of the decal the top and the adhesive layer can make the bottom.

Alternatively, however, the bottom can also be formed by a masking paper, which prevents premature unintentional sticking of the adhesive layer. This can also be formed with a release layer, in particular of silicone or wax material.

The lacquer and / or color layer and / or the adhesive layer may have at least 50% by weight of a polyurethane and / or acrylate, which has proven to be comparatively insensitive to laser radiation. A lacquer layer in the sense of the present invention, in contrast to a color layer, has a functional character. In particular, protective effects, ie the use as a protective layer to protect an underlying color layer, can be realized thereby. In contrast to decoratively effective layers of paint, a lacquer layer is also transparent or semitransparent and controls the degree of gloss.

A color layer is delimited, in particular by the use of other additives, the application, for example by screen printing and pigments, of a lacquer layer.

In addition, the color layer may have at least one further non-laser-reactive pigment, in particular TiO ₂ , carbon black or the like, in order to achieve greater contrasting during color change.

Furthermore, according to the invention is a decal, which was prepared by the aforementioned method.

• 1 schematische Darstellung einer Ausführungsvariante eines bereitgestellten Abziehbildes zur Verwendung in einem erfindungsgemäßen Verfahren zur Erzeugung des laserveränderten Abziehbilds;
• 2 schematische Darstellung einer Laserbestrahlung des Abziehbildes der 1;
• 3 zurückgebliebene Farbschichten auf einem Untergrund nach Auftrag des Abziehbildes; und
• 4 schematische Darstellung einer alternativen Laserbestrahlung im Vergleich zu 2.

The invention will be explained in more detail with reference to an embodiment. The particular details are in no way limiting. In particular, numerous details can be taken for granted as separate features in analogous manner implemented in further embodiments are shown:

• 1 schematic representation of an embodiment of a provided decal for use in a method according to the invention for generating the laser-modified decal;
• 2 schematic representation of a laser irradiation of the decal of 1 ;
• 3 remaining paint layers on a substrate after application of the decal; and
• 4 schematic representation of an alternative laser irradiation compared to 2 ,

1 shows a decal in the form of a multilayer arrangement 1 comprising a carrier film 2 , a sequence of several layers of paint and / or varnish 3 and 4 , an adhesive layer 5 and a masking paper 6 ,

The carrier foil 2 , Also called carrier, can be at least 50 wt.% Based on the total weight of the carrier film 2 , preferably completely formed from a polyethylene terephthalate. Of course, the carrier film may also consist of other materials.

The carrier foil 2 can also with a release layer 8th be coated. This separation layer 8th may preferably be based on at least one silicone and / or a wax material or for the most part, in particular more than 50 wt.% Based on the total weight of the release layer, have. In addition, however, the release layer may also comprise other materials. The separation layer 8th is on the color layer 4 facing side of the release film 2 arranged.

Preferably, the carrier film is 2 transparent or at least translucent. The carrier foil 2 also has a thickness of 75 to 130 microns.

The order 1 may be adjacent to the carrier film 2 or to the release layer 8th an optional varnish layer 3 exhibit. This may be as a layer comprising at least 50% by weight, based on the total weight of the lacquer layer 3 , be formed on binders on polyurethane and / or acrylate-based layer.

Furthermore, varnish layer 3 advantageously additionally enriched by additives, such as leveling agents.

Adjacent to the paint layer 3 can then one or more color layers 4 be arranged. A preferred ink layer may comprise at least about 50% by weight, based on the total weight of the respective ink layer, of a binder. The binder may be formed on polyurethane and / or acrylate-based. Furthermore, the color layer 4 Pigments, preferably but not exclusively white pigments, particularly preferably with TiO2, and / or additives, particularly preferably film formers, have.

The one or more lacquer and / or color layers 3 and or 4 are in particular with a laser-reactive pigment 7 or a laser-reactive pigment-containing granules or powder, which can be excited by laser radiation to a permanent color change. The pigment may in particular be selected from substances comprising: SnSb oxide, Sb ₂ O _3, Cu ₃ (PO ₄ ) ₂ Cu (OH) ₂ , mica (phyllosilicate and / or mica), Fe ₃ O ₄ or mixtures. Likewise, these are characterized by a size between 1 and 70 microns. The laser-reactive portions may preferably be contained in a powder or granules and thereby be encapsulated or unencapsulated.

Adjacent to the paint and / or paint layer is an adhesive layer 5 for fixing one or more of the aforementioned layers on a substrate 10 intended. The adhesive layer 5 may be at least 50 wt.%, Based on the total weight of the respective ink layer, a polyurethane and / or acrylate, and optionally additives, have. The adhesive layer can be permanently adhesive in the case of decals, or, in particular in the case of heat transfers, can be activated by heat. This can be for example a so-called hot melt adhesive.

The adhesion of the adhesive layer is usually so high that a non-destructive redetachment of the decal or heat transfer is not possible.

A masking paper 6 may be adjacent to the adhesive layer 5 be arranged. This paper can also optionally but not exclusively, with a release layer 9 be coated.

This separation layer 9 may preferably be based on at least one silicone and / or a wax material or for the most part, in particular the aforementioned silicone and / or wax material to more than 50 wt.%, Based on the total weight of the release layer have. In addition, however, the release layer may also comprise other materials. The separation layer 9 is on the adhesive layer 5 facing side of the cover paper 6 arranged.

The separation layer 9 and the masking paper 6 prevent accidental premature bonding of the adhesive layer 5 ,

Each of the aforementioned layers, in particular all of the aforementioned layers, may be water- or solvent-based, i. the application is carried out in a solution of water and / or a solvent.

In the following, methods for producing the decal will be briefly explained:

In a first step, see 1 , the provision of the multilayer arrangement takes place 1 with the carrier foil 2 , the masking paper 6 , the or the lacquer and / or color layer (s) 3 and or 4 and the adhesive layer 5 ,

In a second step, see 2 , the laser treatment of the provided arrangement takes place. This is a laser beam 101 a laser source 100 passed through the transparent or translucent carrier film and excited to a color change and thus a change of the decal is generated. Alternatively, the laser can also be directed from the back directly to the transfer this is in 4 shown. In 4 the introduction of the laser beam from one of the carrier film takes place 2 opposite side on the paint and / or color layer 3 . 4 ,

The adhesive layer 5 can, as in 4 already shown on the paint and / or paint layer 3 . 4 be applied or applied only after the Bestahlung.

The reason for this color change is the excitation of the laser-reactive pigments 7 or the powder or granules by the laser beam 101 , In particular, in this case also the surrounding polymer can be dyed indirectly.

The aforementioned laser-reactive pigments or pigment-containing granules absorb the laser light and enable color change. This can i.a. also include carbonation or foaming. Typically, these phenomena occur simultaneously, with the color change of the polymer being predominant to avoid damage by combustion. This is also to be seen in contrast to the labeling by pure combustion of a coloring or other organic layer.

It is also possible that the matrix surrounding the pigment, e.g. the binder of the color layer or the material of which the color layer is predominantly formed is dyed. This can e.g. by rearrangement of complexes, by phase changes or the like.

Then in a third step, the release of the cover paper 6 from the adhesive layer 5 providing an adhesive surface for fixing the decal and the job on a substrate 10 ,

The substrate may be, for example, a stone, glass, wood, metal or preferably plastic substrate

In a fourth step, the removal of the carrier film then takes place 2 from the paint and / or paint layers 3 . 4 , with the decal on the ground 10 remains.

The aforementioned second and third steps may alternatively be interchanged in the order, so that first the application of the arrangement 1 comprising the carrier layer 2 to the underground 10 followed by laser treatment to produce the decal.

As a laser-modified decal 20 In the context of the present invention, laser-modified heat transfer is understood as meaning the modified decal or heat transfer, which has been individualized by laser irradiation by color patterns of the paint and / or varnish layer.

This decal 20 remains in the result without carrier film on the substrate to be decorated 10 ,

As a laser for labeling, a semiconductor laser, such as a YVO ₄ laser or YAG laser can be preferably used. The preferred wavelength range may be between 550 and 1070 nm.

Most preferably, it is a laser that has a 3-axis scanning system. In this case, the additional Z-axis can also be used, for example, to set the autofocus position and / or to set the focal length distance. The focal distance may be due to a secondary laser beam which is in addition to the laser beam 101 , which makes the energy input into the arrangement, are determined.

Particularly preferred may be the paint or color layer 3 and 4 comprise several layers, so that in color change of the pigment, a depth effect or different intense color changes are observed and thus a color gradation can be achieved or a general imaging by the pressure such as screen printing, is given.

By changing the intensity and / or the wavelength of the laser, in addition, the intensity of the energy input and thus the intensity of the color change can be varied. To ensure the correct parameters, so-called parameterization tests are to be carried out for each print batch.

By using different layers with mutually different pigments, the color variance can be additionally increased.

In 1 is just a color layer 4 shown. It can advantageously at least five, preferably at least seven, superimposed color layers 4 be provided.

Each of these color layers may comprise a laser-reactive pigment.

The decal or the heat transfer provided in step a) may in one embodiment of the invention be monochromatic, e.g. know, be educated.

However, the decal provided in step a) or the heat transfer may also already be a printed layer, for example as a color layer or decorative layer below the color and / or lacquer layer 3 . 4 have, which were printed with conventional printing methods, such as screen printing. In this case, the laser treatment can supplement pre-printed decor with a drawing or lettering. As a result, an individualization eg of a logo can be achieved.

LIST OF REFERENCE NUMBERS

1

arrangement

2

support film

3

paint layer

4

coat of paint

5

adhesive layer

6

Masking

7

pigment

8th

Interface

9

Interface

10

underground

20

decal

100

laser

101

laser beam

A

line of sight

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 1020014115910 [0003]
• DE 9429174 U1 [0004]
• WO 2017/108623 A1 [0005]

Claims (12)

A method of making a laser modified decal (20) or heat transfer comprising the following steps a) providing a multi-layered decal (1) or heat transfer comprising at least one carrier film (2) and a paint and / or ink layer (3, 4) with laser-reactive pigments (7); b) providing the paint and / or ink layer (3, 4) with a lettering and / or a drawing by a laser beam (101) of a laser (100) and application on a substrate (10) before or after the aforementioned laser irradiation; and c) removing the carrier film (2); wherein the laser beam (101) passes through the carrier film (2) onto the paint and / or ink layer (3, 4) and / or onto the paint and / or ink layer (3, 4) from one side opposite the carrier film (2) ). Method according to Claim 1 characterized in that a color change of the pigments (7) or indirectly of the surrounding polymer takes place by the laser beam, wherein the number of excited pigments and thus the intensity of the color change by the laser adjustment, in particular the intensity of the laser beam (101) and its wavelength, varies or is adjusted. Method according to Claim 1 or 2 , characterized in that the production of the laser-modified decal (20) by color change of the laser-reactive pigments, in particular ink-free, takes place. Method according to one of the preceding claims, characterized in that the multi-layered decal (1) or the multi-layered heat transfer in step a) between the carrier film (2) and the paint and / or ink layer (3, 4) a release layer (8 ), preferably based on silicone and / or wax. Method according to one of the preceding claims, characterized in that the carrier film (2) has a thickness between 75 to 130 microns. Method according to one of the preceding claims, characterized in that the laser (100) in step b) is operated with a power up to 20 W. Method according to one of the preceding claims, characterized in that the lacquer and / or color layer (3, 4) on one of the carrier film (2) opposite side has an adhesive layer (5). Method according to one of the preceding claims, characterized in that the lacquer and / or color layer (3, 4) and / or the adhesive layer (5) at least 50 wt.% Has a polyurethane and / or acrylate. Method according to one of the preceding claims, characterized in that the ink layer (3, 4) at least one further non-laser-reactive pigment, in particular TiO ₂ , having. Method according to one of the preceding claims, characterized in that the multi-layered decal (1) or the multi-layered heat transfer in step a) also a cover paper (6), in particular a cover paper (6) with a release layer (9), to protect Adhesive layer (5). Method according to one of the preceding claims, characterized in that the multi-layered decal and / or the multi-layered heat transfer (1) are designed to be flexible. Decal (20) produced by a method according to one of the preceding claims.

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