EP0616904B1 - Method and means of applying identification marks - Google Patents

Abstract

In a method for applying identification marks (10,16) on a sheetlike ground (12), the latter is provided with a base layer (18) of an adhesive which is or becomes transparent and then a pliant base web (14) which bears the mark (16) and whose format is at most that of the bed of adhesive (18) is pressed on, whereupon at least one further layer of adhesive (20) is applied with smoothing of the web (14) underneath. Preferably the web (14) has been lightly impregnated with a wet strength enhancer and is printed after it has dried with the mark (16) which is applied to the web (14) as a matter of choice in one or more colours and is heat-set thereon, for example 40 s at about 180@C. Of particular suitability is a paper web (14) having a basis weight below 25 g/m, a wall thickness of 10 to 500 mu m, preferably 50 to 100 mu m, and an average pore size of 100 to 300 mu m, preferably 150 to 250 mu m. The mark (16) consists of a very finely disperse, thinnable, light- and weather-resistant ink which has a solids content of not more than 20%.

Description

The present invention relates to a method for applying markings according to claim 1 and to marking means according to claim 8.

To label any objects, one uses printed stickers or the method of etching and / or coloring the body in question using a template. Tools and other objects for advertising purposes, protection against theft, etc. are often marked with glued-on foils. Very thin special foils adhere more or less well with appropriate adhesives, but can be removed relatively easily by heating and are with a solvent, with sharp-edged tools and the like. at least damage, so that the label is violated or unrecognizable. In many cases there is no weather resistance; self-adhesive films on raw wood in the outside area can be removed by moisture in a very short time. In addition, printed films can generally only be applied to clean and smooth substrates that are adhesive to the surface and in any case dust-free.

The same applies to decals according to US-A-2 094 430, which first receive a layer of water-soluble adhesive on a water-permeable carrier and then a layer of cellulose derivative. A pattern to be transferred is printed on this, which after drying is coated with a second cellulose derivative layer and by the two Layers must be covered overlapping. If the adhesive is dissolved in water and provided with a hardener, the decal can be applied to a glass surface, for example. The many work steps make the process very complex. Due to the multi-layer structure and low adaptability, durability on rough, not entirely clean surfaces is hardly achievable.

Also from US-A-1 926 685 decals that can be coated with lacquer or varnish are known, the pattern to be transferred is applied to a solvent-resistant transparent carrier which is provided on one or both sides with a water-insoluble layer and can be stuck to a base which in turn is smooth have to be. At most, very small motifs can be attached to non-absorbent surfaces.

EP-A-0 503 738 describes a method for applying patterns, images, lettering or the like. on cars. For this purpose, a transparent carrier made of polyester is provided with an adhesive layer and, after heat treatment, printed with a desired pattern or picture. A further adhesive layer and a protective layer are applied to the pattern, which are punched out together with the lower adhesive layer in accordance with the pattern. To apply the pattern, first remove the protective layer, which exposes the pattern with the remaining adhesive layer. The carrier is then turned over, placed on the surface and removed, the pattern adhering to the surface. In order for a lettering to appear legible, the carrier must be printed in reverse mirror image. Otherwise you have to remove the pattern from the carrier with a transfer belt and transfer it to the surface. In any case, the surface must also be free of dust and grease in order to achieve a certain durability,

Even with good adhesion of the adhesive used, such decals can be mechanically, e.g. with a fingernail, scraped off or at least damaged. Furthermore, since the cohesion in the decal is significantly higher than the adhesion to the substrate that can be achieved, cracks can form, which leads to peeling. The protective layers also become blind over time; then the motif can no longer be recognized or can only be recognized with difficulty.

For scaffold inscriptions, signs and other essentially flat surfaces, paint is applied using stencils, which, however, generally only allow single-color identification. Without template bars, fine, uninterrupted lines cannot even be achieved in one color, let alone multi-colored. Repainting is from The cost and time involved cannot be carried out economically, even with small quantities. In addition, stencils on curves, waves, angled and profiled surfaces etc. are not or only very difficult to use.

Screen printing is generally only possible on smooth substrates. In addition, this is only profitable if the objects to be printed can be placed on a printing table and a larger amount of the same parts is printed. In addition, a fit must be provided for multi-color prints. These requirements are not met with different scaffolding parts, curved signs or similar objects; Large bodies also cause transportation problems.

There are also so-called transfer prints, which are mainly used to textiles of various types with patterns, labels or the like. to provide. Here, motifs are printed on suitable carrier papers by means of screen printing, which are then transferred to the object to be printed with pressure and heat in a transfer press. To apply transfers to rigid substrates, the procedure is to remove the printing layer from the backing paper with water and apply it to the respective substrate. For weatherproof and mechanically stable transmission e.g. Such transfers are not suitable or only suitable to a very limited extent on heavily used industrial floors or scaffolding, where sharp-edged parts are pushed one above the other. Textile transfers cannot often be transferred to these rough, uneven and unclean surfaces. Water-soluble transfers do not have the necessary adhesion to the surface or are not mechanically strong. Although foils can be weatherproof, they do not withstand mechanical loads, especially in the floor area or when flat parts are touched by rigid parts that are moved against each other under load, e.g. Scaffolding parts during loading.

There is therefore an urgent need, in particular transportable rigid objects such as scaffolding parts, tools, formwork and the like. identified by a distinctive mark that is as difficult to remove as possible. The object of the invention is to provide methods and means for this and to permanently affix such markings in a simple manner. In buildings and large halls, it should also be possible to place notes or information on rough wall surfaces such as exposed concrete or on the floor, especially if the necessary wall surfaces are blocked or not available at all.

To achieve this object, the invention proposes the method according to claim 1 with configurations according to claims 2 to 7. The invention also relates to labeling means as specified in claims 8 to 14.

The method according to the invention for affixing markings to a flat surface provides that this is provided with a base layer made of a transparent or transparent adhesive and a base fleece with the identification is pressed into it, the format of which at most reaches that of the adhesive base layer, after which it is smoothed of the carrier fleece applies another layer of adhesive. This results in a weatherproof and mechanically highly resilient, distinctive marking, which is suitable for all rigid surfaces indoors and outdoors, but also for elastic bodies and for round, angled or wavy objects, uneven floors and walls, profiled panels or the like. The method allows such durability to be marked that removal or blurring is extremely difficult. It is therefore particularly well suited for the application of security labels, permanent information or for theft protection. With extremely simple means, a visually appealing, also effective advertising design is made possible.

Embodiments of the method are specified in claims 2 to 7. Preference is given to using nonwoven support fleeces soaked with a wet strength agent, which are printed with the label after drying. It is particularly advantageous if the marking is applied to the carrier fleece by optionally one-color or multi-color screen printing and is heat-set for at least 40 s at a temperature of approximately 180 ° C. The application of at least one cover layer, in particular from the same adhesive material, results in an all-round, homogeneous embedding of the carrier fleece.

As a marking agent, a transfer for application to a flat surface, in particular for carrying out the above-mentioned method, is specified in claim 8, the main component being a pliable carrier fleece which is printed with a marking, onto which an adhesive bed of at least the same size is made from a transparent or becoming transparent Adhesive-provided substrate can be applied well and covered with at least one adhesive layer.

Advantageous further developments are given in claims 9 to 14. The fleece is preferably a specifically light, thin paper fleece impregnated with a wet strength agent, the basis weight of which is below 25 g / m ² with a wall thickness in the range from 10 to 500 μm. Nonwovens whose average pore size is in the range from 100 to 300 μm are favorable. Nonwovens made from long-fiber material can be used with advantage, e.g. from manila hemp, sisal or palm fibers. Printing is greatly facilitated if the marking consists of heat-set, finely dispersed, water-dilutable, light and weather-resistant ink, which has a solids content of at most 20%. If the marking agent is also coated with a final layer of lacquer, this increases the durability of the applied transfers.

Fig.1

eine schematisierte Draufsicht auf einen Untergrundkörper mit aufgebrachtem Transfer in verschiedenen Verfahrensstufen,

Fig.2

eine schematisierte Schnittansicht entsprechend der Linie II-II in Fig.1 und

Fig.3

eine vergrößerte Querschnittsansicht einer besonders vorteilhaften Ausführungsform.

Further features, details and advantages result from the wording of the claims and from the following description of exemplary embodiments with reference to the drawing. In it show:

Fig. 1

2 shows a schematic plan view of an underground body with transfer applied in different process stages,

Fig. 2

a schematic sectional view along the line II-II in Fig.1 and

Fig. 3

an enlarged cross-sectional view of a particularly advantageous embodiment.

The application of a transfer, generally designated 10, to a substrate 12 is shown schematically in FIG. 1. The base 12 is provided with an adhesive base layer 18, also referred to as an adhesive bed, in which a fleece 14 of at most the same size is embedded, most simply by pressing in with a soft brush. Immediately afterwards, the fleece is coated with another layer of adhesive 20, expediently from the inside out until freedom from wrinkles and bubbles is ensured. After drying, a top coat can be applied if desired.

If white glue is used as the adhesive, the fleece initially appears white on the adhesive bed 18. Even as it is pressed into the adhesive bed 18, both become milky-light; The fleece 14 is already transparent when the further adhesive layer 20 is applied. It becomes completely transparent when the cover layer 22 is applied, so that the delimitation of the fleece 14 can only be seen at close range and the marking clearly stands out. You can still apply more layers of adhesive, with each subsequent layer, the fleece 14 with its boundary optically disappears more and more, so that only the marking 16 comes out sharply.

Fig. 2 shows the structure in schematic cross section. It can be seen that the transfer 10 or fleece 14 pressed into the adhesive base layer 18 is embedded in adhesive on all sides by the coating with the further adhesive layer 20. Dashed lines indicate that the further adhesive layer 20 need not be limited to the original area of the adhesive bed 18. The cover layer 22 made of adhesive or lacquer is indicated by dash-dotted lines. The size ratios are greatly exaggerated, since the fleece 14 and the adhesive layers 18, 20, 22 are extraordinarily thin overall.

3 shows a cross section through the finished structure even more enlarged; it can be seen that the outer surface is significantly smoother than the rough surface 12. The transfer 10 or fleece 14 is embedded in the adhesive bed 18 such that, thanks to its porosity, the adhesive of the layers 18, 20 penetrates it. In order to make the transfer 10 with printed areas 24 and unprinted areas 26 stand out more clearly in the illustration, the adhesive in the longitudinal center of FIG. 3 has been omitted, but is actually present.

For the production of the transfer 10, a fine paper fleece 14, which can also be stretched in the solvent, is used in the quality approximately as for teabag filters. Its specific weight per unit area is in the range from 10 to 25 g / m ² and the wall thickness in the range from 0.05 to 0.5 mm, preferably from 0.10 to 0.15 mm. The average pore size can be 0.15 to 0.25 mm. The fleece 14 is slightly impregnated with a wet strength agent such as epichlorohydrin resin or melamine resin so that it can better withstand the effects of moisture. The high porosity is retained and embedding in a base layer 18 is possible even with the use of an adhesive with a high solid content and full surface coverage with only one gluing process.

A finely dispersed, lightfast, water-thinnable, weather-resistant printing ink of the type usually used in screen printing is advantageously used for printing. Heat-fixing inks or so-called flexographic printing inks are advantageous. The residual moisture is removed by a fixation, for example, at about 180 ° C. for at least 40 s and the fleece becomes more flexible and cuddly at the same time. This is extremely cheap, especially on uneven surfaces. The solid content of the printing ink is expediently below 20% in order to achieve a print job that is as imperceptible as possible. In addition, the printing ink should not form a layer around the fiber, so that a largely homogeneous layer of the adhesive is created and the adhesive itself soaks the fiber.

A water-resistant white glue can be used as an adhesive, which, when added with a hardener, achieves stress group B4 according to DIN 68602 for wood gluing. The fresh white glue makes the transparency 10, ie the fleece 14 printed with the marking 16, extremely flexible and therefore pliable. The white glue dries transparently. It mainly contains PVA = polyvinyl acetate as a non-yellowing and weather-resistant binder.

While white glue is preferred, particularly indoors, on wavy surfaces, for designing doors, etc., a PUR adhesive (polyurethane base), e.g., is suitable for applying the transfers 10 to smooth metallic or painted surfaces. Polyurethane isocyanide. This is water vapor permeable even with a higher layer thickness of, for example, 0.7 mm and adheres to all non-slip materials such as steel, aluminum, hard plastics, glass fiber reinforced plastics, etc. Accordingly, the adhesive layers 18, 20, 22 with expansions of up to 300% are permanently elastic. Detachment by chemical means was not successful in the test; at most, violent scraping with tool aid or mechanically is possible. Thanks to its high UV resistance, there is no yellowing.

Regardless of which adhesive is used, the weather resistance can be increased by at least one cover layer 22. Tests have shown that the applied transfers 10 are very durable even without a protective layer or varnish, at most the transparency can decrease somewhat over time. However, this remains practically without influence on the marking 16 and its clear recognition.

The attachment can be carried out on all possible surfaces such as wood, steel, aluminum, scaffolding or scaffolding parts, coated industrial flooring, stoneware flooring, etc. The surfaces can be smooth, but also uneven, such as a wall plaster surface; Wavy, profiled or rough surfaces are also suitable. If no value is placed on absolute flatness, slight dust can be incorporated when applying the adhesive. With a previous application of a primer, especially with non-ferrous metals, the durability can be improved.

The invention contributes particularly to theft protection and to the permanent unmistakable identification of the objects in question. In the embedded fleece 14, the marking 16 cannot be removed without mechanical means, even if the transfer 10 has been attached at angles or fillets. Overpainting the embedded transfer 10 with a two-component lacquer, for example, prevents detachment even when using an aggressive paint stripper.

The invention is not restricted to the exemplary embodiments shown. However, it can be seen that a preferred embodiment proposes a method for applying markings 10 on a flat surface 12, in which the latter is provided with a base layer 18 made of a transparent or transparent adhesive and then a flexible carrier fleece 14 having the marking 16 is pressed in , the format of which at most reaches that of the adhesive bed 18, whereupon at least one further adhesive layer 20 is applied while smoothing the fleece 14. The fleece 14 is preferably slightly impregnated with a wet strength agent and, after it has dried, is printed with the optionally single-color or multi-colored marking 16, which is heat-set, for example, at about 180 ° C. for 40 s. A paper fleece 14 with a basis weight below 25 g / m ² , a wall thickness of 10 to 500 μm, preferably 50 to 100 μm, and an average pore size of 100 to 300 μm, preferably 150 to 250 μm is particularly suitable. The finished marking 10 consists of finely dispersed, dilutable, light and weather-resistant ink, which has a solids content of at most 20% and is suitable for screen printing or flexographic printing.

Reference numerals - list

10th

transfer

12th

Underground

14

Carrier fleece

16

Labelling

18th

Glue bed

20th

Adhesive layer

22

Top layer

24th

printed areas

26

unprinted places

Claims (14)

1. A method of applying identification marks to a planar substrate by providing the substrate with a basic layer of adhesive which is or becomes transparent, and by pressing a carrier web including the identification mark into the basic layer, the size of the carrier web being not more than the size of the basic adhesive layer, whereupon a further adhesive layer is applied to the carrier web with the latter being smoothed.
2. The method according to claim 1, wherein prior to being pressed into the basic adhesive layer the carrier web is impregnated with a wet-strength agent, preferably at an impregnation amount of less than 2% to 6%, based on the weight of the web.
3. The method according to claim 2, wherein the carrier web has the identification mark printed thereon after the impregnation has dried.
4. The method according to claim 3, wherein the identification mark is applied to the carrier web optionally in one or a plurality of colors and is heat-set.
5. The method according to claim 4, wherein the identification mark is heat-set at a temperature of about 180°C for at least 40 s.
6. The method according to any one of claims 1 to 5, wherein at least one adhesive and/or varnish layer is applied to the adhesive layer covering the carrier web.
7. The method according to any one of claims 1 to 6, wherein the basic adhesive layer as well as the adhesive layer and every further adhesive layer are made of the same material so that the carrier web is homogeneously embedded on all sides and absorbs binders.
8. Means of applying identification marks, particularly transfer (10) for application to a planar substrate (12), namely for performing the method according to any one of claims 1 to 7, consisting of a flexible carrier web (14) which has an identification mark (16) printed thereon and can liberally be applied to the substrate (12) which is provided with an at least equally sized adhesive bed (18) of an adhesive which is or becomes transparent, with the carrier web (14) being coatable with at least one adhesive layer.
9. The means according to claim 8, wherein the web (14) is a specifically lightweight, thin paper web impregnated with a wet-strength agent, such as epichlorohydrine resin or melamine resin.
10. The means according to claim 8 or 9, wherein the weight per unit area of the web (14) is below 25 g/m² and the wall thickness thereof ranges from 10 to 500 µm.
11. The means according to any one of claims 8 to 10, wherein the average pore size of the web (14) ranges from 100 to 300 µm.
12. The means according to any one of claims 8 to 11, wherein the identification mark (16) consists of a heat-set, extremely finely disperse, water-dilutable, light-fast and weather-resisting ink which is suited for screen printing or flexo printing.
13. The means according to claim 12, wherein the printing ink has a solid content of not more than 20%.
14. The means according to any one of claims 8 to 13, wherein the means is coated with a final layer of varnish.

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