DE1902632C3 - Self-adhesive decal - Google Patents

Description

45

The invention relates to a self-adhesive transfer for production which can be applied by light pressure of a pattern on a preferably heat-resistant, possibly curved base that consists of a backing layer, a separating layer, a pattern layer and a layer of a pressure-sensitive adhesive having high tack.

Self-adhesive decals have been known for a long time, but have several disadvantages. So They usually contain pressure-sensitive adhesives with low tack, which is an essential Require pressure to adhere to the receiving surface of a heat-resistant pad, so that their application on irregular surfaces or surfaces with complex curvatures does not succeed in a satisfactory manner

From GB-PS 9 91 640 decals are made of a backing layer, a separating layer, a pattern layer and a high tack pressure sensitive adhesive layer are known, but not can be stacked on top of each other, because then neighboring images will stick together and no longer in unstacked easily and satisfactorily

60

can be.

The object of the invention is to provide self-adhesive decals for the application of decorative and other To create patterns on preferably heat-resistant and possibly curved surfaces, soft these documents can be applied under slight pressure and can be used for storage and transport purposes can be stacked and easily unstacked again if necessary.

The decals according to the invention are characterized in that at least partially on each A separating layer is applied to the surface of the backing layer, the separating layers being different Peel off properties.

The separating layers with different peel properties are preferably made of polysiloxane material which has the general formula (R ₂ SiO) _n , where π is a positive integer and R in the simplest case is methyl groups. However, one or more of the methyl groups can be replaced by other alkyl groups and, depending on the substituents used, monomeric polysiloxane materials can also be modified in order to form a crosslinked molecule, resulting in a two- or three-dimensional polymer

The peel properties of a release liner mainly depend on two factors, namely the Composition of the release layer - a chemical factor - and relative smoothness (or Roughness) of the surfaces of the backing layer to which the separating layer is applied - one mechanical factor. For a separating layer, which has a certain chemical composition, therefore the peeling properties depend on the mechanical factor. For example, is the extent of Adhesion, or the mechanical bond between a relatively smooth surface and a film, a Color or an adhesive is relatively low, so the peel properties are good. On the other hand, the same film, paint or a binder on a less smooth surface, for example a coarse-grained one Surface, applied, the result is a relatively good mechanical bond.

The thickness of the release liner is usually such that the contour line or finish of the surface the separating layer is almost followed by the machining or contour line of the backing layer, or is in this reflects. So it is in the case that a release layer is applied to a backing layer with a smooth surface is, the surface of the release layer is also smooth and in the event that the backing layer has a rough or has a coarse-grained surface, the surface of the separating layer also has a rough or coarse-grained one Surface. This concept, that the machining or the contour line of the surface of the backing layer is in the machining or contour line of the separating layer is used in the invention to denote the Tendency of the decals to so-called "blocking", i. H. for gluing adjacent decals together in a pile, to diminish.

According to a feature of the invention, the surface of the backing layer, which is a separating layer, the pattern layer and the pressure-sensitive adhesive layer with high tackiness is smoother than the surface of the backing which carries a single release liner. Assuming the Decals in a stack with the layers of high tack pressure sensitive adhesive

are arranged at the top (which is usually the case), the second mentioned or single Separation layer has a relatively smaller contact surface area to the high tack pressure sensitive binder layer, i.e., des next decal in the stack, with easy removal of the decals from the stack It has been found that a backing layer with a peel strength of not higher than 1.2 g / cm for the side is suitable which has a release layer, pattern rail and adhesive layer with high adhesive pressure sensitivity carries, and that a peel strength not higher than 6 g / cm for the opposite Surface is suitable, which carries the individual separating layer

The backing layer may be in sheet or strip form and one or more layers may be one include flexible material. Suitable materials include:

1. a polyethylene of low to medium density, for example 0.92 to 0.935 g / cm ³ ;

2. a paper / polyethylene laminate;

3. a polyethylene / paper / polyethylene laminate;

4. Polyethylene or polyethylene / paper laminates;

5. paper, and

6. a flexible sheet material.

A backing-separating layer combination, which has been found to be particularly suitable, is located in the Commerce and includes a polyethylene layer which on each of its surfaces with a layer of a Polysiloxane material is coated

The pattern layer can be applied to the backing layer with the help of a screen, cliché, high-; Dry offset _: flexographic printing process or a lithography process or any combination thereof can be applied. The adhesive layer can be applied as a complete overcoat using any of the normal coating techniques, or it can be bonded to the decorative or other patterned surface by printing the adhesive by screen or cliché or flexographic printing techniques.

The decal made in this way can be put on heat-resistant or other documents such as cans, bottles, plastic containers and the like, either manually or automatically in die-cut form or from an endless path, d. H. with the back layer or the film in the form of a strip or tape. When applying such The decal binds the highly adhesive layer of adhesive to the heat-resistant base. As a result of low bond strength between the adhesive / pattern layers and the backing, which is made by a combination of color compositions and caused by surface properties of the backing, the latter can be easily removed, leaving the other decorative pattern firmly adhered to the heat-resistant base If paint is used with polyethylene films, the paint layer itself must be sufficiently flexible to allow for the Allow application of the pattern to surfaces with complex curvature. The manufacture of Decals according to the invention can also be used for the production of self-adhesive labels will.

The printing ink for the decorative or other

Pattern can be built on a variety of materials, such as nitrocellulose and cellulose esters, modified rosin, alkyd resins ^ condensates from cyclic ketones, maleic, amine and acrylic resins.

Acrylic resins are preferably used and it is desirable to add a plasticizer to the paint medium and surfactants to achieve the desired film-forming properties and peel properties admit it.

A typical color approach based on an acrylic resin is:

pigment 60% Acrylic resin 14.5% solvent 22.0% Plasticizers 1.5% Surface active substance 2.0%

100.0%

The coloring material used can be the heat-resistant one, depending on the intended use Base composed of an inorganic pigment with a proportion of a vitreous material be as it is well known to the person skilled in the art, or on the other hand in the case that the heat-resistant Underlay that is not exposed to high temperatures can be a heat-resistant organic pigment be added.

For example, a flux or a glass matrix made of lead silicate, lead borosilicate or lead alkali borosilicate with smaller amounts of modifying oxides and the addition of known, inorganic color compositions, such as cobalt aminate, cobalt sulfate, cadmium sulfoselenides or lead antmonth. Organic pigments can also be used provided they are lightfast and Heat-resistant up to at least 200 ° C (for non-ceramic uses). Typical pigments, which

have these properties are: isoindolinone yellow, orange and red dyes, dioxazine violet dyes, Phthalocyanine blue and green dyes. The following are examples of acrylic resins, solvents, plasticizers and surfactants listed:

Acrylic resins

Methyl methacrylate / butyl methacrylate copolymer, 2-ethyl hexyl acrylate and polybutyl methacrylate.

solvent

Esters such as amyl and butyl lactate aromatic Hydrocarbons, for example xylene, alcohols, for example diacetone alcohol, glycol ether esters, for example 2-ethoxyethanol acetate; however, other well known solvents can also be used.

Plasticizers

Dioctyl phthalate, dibutyl phthalate and butyl phthalyl butyl glycolate; however, others, well known Plasticizers can also be used.

Surface active substances

In order to achieve good film-forming properties when printing on silicone coatings, it is necessary to add surface-active substances to the printing medium. Stearic acid proved to be suitable materials and their derivatives, Glycerinir.onostearat, and

Stearic acid amide (known commercial product).

Various examples of specific color compositions with inorganic and organic Pigments are given below:

Inorganic coloring compositions for use in ceramic articles.

1. Cadmium Red; ceramic enamel
Polybutyl methacrylate
Xylene

Amyl lactate
Dioctyl phthalate

commercially available surfactant
Funds on the base
Stearic acid amide

64.3%

14.2%

8.4%

9.5%

1.8%

100.0%

61.5% 16.0% 18.8%

1.9% 1 on /.

I, U YU

100.0% 67.3%

13.5% 15.5% 2.0% 1.7%

100.0% color compositions with organic colors

2. lead antimony yellow; ceramic enamel
2-ethyl-hexyl acrylate
Amyl lactate

Butyl phthalyl butyl glycolate
Stearic acid

3. cobalt blue; ceramic enamel
Polybutyl methacrylate / methyl methacrylate copolymer
Diacetone alcohol
Dibutyl phthalate
Glycerol monostearate

4. Commercial yellow dye
Polybutyl methacrylate
Xylene
Amyl lactate
Dioctyl phthalate
commercial surfactant based on
Stearic acid amide

5. Commercially available orange dye
2-ethyl-hexyl acrylate
Amyl lactate

Butyl phthalyl butyl glycolate
Stearic acid

6. Commercial blue dye
Poiybutyl-nieihäeryjät / Meihy! -
methacrylate copolymer
Diacetone alcohol
Dibutyl phthalate
Glycerol monostearate

18.0% 36.0% 18.0% 24.0% 1.0%

3.0% 100.0%

15.0%

40.5%

40.5%

1.5%

2.5%

100.0%

10.0%

43.5%

43.5%

1.0%

2.0%

100.0%

The following printing ink compositions have proven to be very general as suitable:

70 - 59% anorg. Pigment content, 12 - 18% Acrylic or methacrylic Homo- or copolymers 15 - 19% org. Solvent, 1.5 - 2% Plasticizers and 1.5 - 2% Stearic acid or stearin acid derivative

B) 20
35

40
2
3

7% org. Colours,
45% acrylic or methacrylic

Homo- or copolymer,
45% org. Solvent,
1% plasticizer and
2% stearic acid or stearic acid derivative

100% 100%

The most suitable pressure sensitive adhesive is one that is quiet on firing with no sagging of a melting range burns off For this reason, adhesives are based on acrylic polymers and acrylic-vinyl acetate copolymers are the most suitable, and it is necessary that the selected material be internally plasticized and permanently tacky. A typical recipe that gives satisfactory results is:

Acrylic resin
alcohol
Ethyl acetate
Hexane

22.25%

50.0%

23.15%

4.6%

100.0%

Alternatively, if the use of an adhesive with even higher adhesiveness is desired the following recipe is suitable:

Acrylic resin

Sucrose acetate isobutyrate
alcohol
Ethyiacetai
Hexane

21.8

2.0

49.0

22.7

4.5

20.5%

7.5%

46.25%

£. I ₁ J "TO

425%

100% 100%

100.0% 100%

Commercially available adhesives of the most varied that are customarily used for the stated purpose are suitable Type. In practice, these substances are made with polymerized and hydrogenated rosin, Modified rosin esters, chlorinated diphenyl compounds and sucrose acetate isobutyrate

Examples of modified substances are a wide variety of commercial ice products, e.g. B. those based on Ethylene glycol esters of polymerized rosin, triethylene glycol esters of hydrogenated rosin, Plastics made from chlorinated diphenylene and polyphenylene, and sucrose acetate isobutyrate

The modifying substances are added in a proportion of 2 to 20% to achieve the desired Adhesive properties, cohesion and shelf life can be achieved using solvents and thinners also added to the adhesive solution in order to achieve the desired flow properties. The solvents and diluents are carefully chosen so that they remove the underlying color layer do not attack or penetrate them. In this regard, alcohols and aliphatic turned out to be

eo hydrocarbons considered satisfactory and typical examples are: nonyl alcohol, 2-ethyl-n-butyl alcohol, White spirit and aliphatic solvents. The solvents that can be used are not limited to these types are limited, for example,

mixtures of esters and aliphatic compounds also satisfactory.

The following are examples of solutions of pressure sensitive adhesives:

commercial adhesive
commercial modifier
based on ethylene glycol ester of

44%

polymerized rosin 5% 2-ethyl-n-butyl alcohol 51% 100% 8. Commercial adhesive 40% Sucrose acetate isobutyrate 20% commercial aliphatic solvent 40% 100% 9. Commercial adhesive 56% commercial modifier based on triethylene glycol ester of hydrogenated rosin 5% Nonyl alcohol 39%

10

10. Commercial adhesive
as under No. 8

commercial modifier
as under No. 9
Butyl lactate
Petrol (turpentine oil substitute)

100%

46.5%

4.5%
19.0%
30.0%

100%

20th

25th

A decal made in accordance with the invention may be single-layer or multi-layered Surfaces of a conductive or insulated or dielectric or semiconducting material or of Resistance material or of two or more such layers on top of one heat-resistant or other Underlay can be used in one step. The conductive material or resistor material, which is contained in a printing medium can be precious metals, for example gold, silver or platinum, or alloys or compounds which contain or include alloys and may contain these metals can then be fired in the open air. However, such materials can include other metals and their Contain compounds, for example molybdenum, which then in the air or in one of the affected material is burned. Alloys of molybdenum and manganese or metals or Alloys of the metals belonging to the eighth group of the periodic table can also be used will. Materials to be applied according to the procedure described include cermet compositions or other materials which are suitable as semiconductors.

The resistor materials can be composed of compounds such as oxides of any of the above metals exist alone or alloyed with one or more of the aforementioned metallic elements.

The conductive or resistor materials can include binders, which can be of a silicate-like nature, for example lead borosilicate or even quartz. This includes but not others using binders, such as Wismutoxy- ^ o chloride and other materials.

Dielectric materials can contain any state-of-the-art material, for example titanates such as barium titanate. Dielectric materials modified with other substances, for example Bismuth titanate, can also contain such binders as above in the description of Resistance materials and conductive materials explained.

Insulating materials can include materials with a glass phase such as lead borosilicate and they are available in two forms, namely as a vitrifiable material, and as a material which germs forms and crystallizes on cooling.

Examples of semiconducting materials are cadmium selenide and the sulfides of Cd, Pb, Zn and mixtures of this.

· The described procedure for applying decorations and other patterns to heat-resistant Documents offers a greater advantage over conventional working methods in that the inventive Decal on the backing without the application of high pressure to activate the Adhesive layer and also on surfaces that are uneven or complex curvatures have, can be applied.

Another advantage is that the transfer picture according to the invention is directly on unglazed biscuit porcelain without the need to seal the pores of the goods beforehand with a primer can.

As for the application of conductive or insulating or dielectric or semiconducting surfaces or resistance surfaces on heat-resistant substrates relates, so these are generally on a base in the form of a ceramic body, for example a ceramic disc, printed. Therefore it was not always possible to get a flat deposit of the printing ink to achieve because of the surface irregularities of the base. A manufactured according to the invention, self-adhesive decal overcomes this deficiency.

The decal has the further advantage that a multi-layered surface in one operation can be applied instead of requiring a series of separate, single coat applications as is often necessary with direct printing.

As an example, two decals according to the invention are shown in the drawing.

In the drawing the different layers of the decals are marked with numbers, where 1 a backing layer, 2 and 3 polysiloxane release layers, 4 a musier layer and 5 a pressure sensitive layer Mean high tack adhesive layer. If the decals according to the invention for decoration are used by ceramic, glass-like or other goods, the pattern consists of one pictorial representation. However, as previously indicated, the pattern can be a resistive material, conductive, semiconducting, dielectric or insulating material for use in the manufacture of electrical Items include.

1 sheet of drawings

Claims (8)

Patent claims: 1. Self-adhesive decal that can be applied with light pressure to create a pattern a preferably heat-resistant, possibly curved base, which consists of a backing layer, a release layer, a pattern layer and a pressure-sensitive adhesive layer high tack, characterized in that that a separating layer is applied at least partially to each surface of the backing layer, the separating layers being different Peel off properties. 2. Decal according to claim 1, characterized in that that the different separation properties due to the relative smoothness of the surfaces the back layer are conditional. 3. Decal according to claim 1, characterized in that that the surface of the backing layer, which is a release layer, the pattern layer and the Layer of adhesive with high tack is relatively smoother than the surface of the backing layer, which only has a separating layer. 4. Transfer according to Claims 1 to 3, characterized in that each separating layer consists of one Polysiloxane material is made. 5. Transfer according to claim 4, characterized in that the polysiloxane material has the general formula (R ₂ SiO) _n , where R is methyl groups and π is a positive integer. 6. Decal according to claim 5, characterized in that that at least one methyl group has been replaced by another alkyl group. 7. decal according to any one of claims 4,5 or ⁵ ^ 6, characterized in that the backing layer is a flexible material made of polyethylene or ^p aper constructed from one or more layers. 8. Transfer according to claim 7, characterized in that the polyethylene has a density between 0.92 and 0.935 g / cm ³ .