DE102007008073A1 - Method for transferring surface structures such as interference layers and holograms to glass, ceramic/metallic substrates, comprises applying flexible intermediate support layer to support film and then embossed sol, and producing a stack - Google Patents

Abstract

The method for transferring surface structures such as interference layers, holograms, and other highly refractive optical microstructures to glass, ceramic or metallic substrates, comprises applying a flexible intermediate support layer to a support film as a release layer, applying an embossed sol with a surface structure to the support layer, producing a stack encompassing a binder layer and the surface structure, removing the support film, and thermally treating the work piece at 450[deg] C. In relief hologram, the structuring takes place via simpler or thixotropic embossing. The method for transferring surface structures such as interference layers, holograms, and other highly refractive optical microstructures to glass, ceramic or metallic substrates, comprises applying a flexible intermediate support layer to a support film as a release layer, applying an embossed sol with a surface structure to the intermediate support layer, producing a stack encompassing a binder layer and the surface structure, removing the support film, and thermally treating the work piece at 450[deg] C. In relief hologram, the structuring takes place via simpler or thixotropic embossing. In the production of the stack, the binder layer is applied on the substrate and dried and then the surface structuring is transferred to the binder layer, and a binding agent is directly applied on the surface structuring and subsequently transferred the stack on the substrate. The transfer of a hot substrate takes place in the thermally treated work piece. The substrate temperature is 150-450[deg] C. The binding agent consists of a nano-composite obtained through surface modification of colloidal inorganic particles and one or more silanes of Rx-Si-A4-x, where A represents hydroxyl groups or hydrolytically separable groups, excluded methoxy, R represents hydrolytically non-separable groups and x is 0, 1, 2 or 3. In the 50% of the material quantity of silane, x is >= 1. Under the condition of the sol-gel-process with an understoichiometric water quantity related to the available hydrolysable groups, if necessary further hydrolysis and condensation of nanocomposite-sols takes place under formation of the nanocomposite-sols.

Description

The The invention relates to a method for transferring surface structuring, like interference layers, holograms and other high-refractive ones optical microstructures on substrates.

When Substrates come here especially glass, ceramic and metal surfaces in question.

The use of transfer films for transferring decors to various substrates, wherein also a burn-in of the decor can take place above or below a glaze, for example, from US 6,766,734 , of the US 6,694,885 and the US 6,854,386 known.

The application of hologram adhesive films on paper or plastic substrates is widespread, such as from the US 5,702,805 and the US 5,318,816 is apparent.

From the KR 2002/024286 A For example, a hologram transfer film and a manufacturing method therefor are known, but are not suitable for glass or ceramic surfaces. In the JP 2004/358925 A a hologram adhesive film is described, which is not einbrennbar. Also in the JP 2003/280498 A a hologram carrying transfer sheet described is not suitable for glass or ceramic surfaces, which is also the case in the subject of the US 5,702,805 A ,

• a) kolloidalen anorganischen Partikeln mit
• b) einem oder mehreren Silanen der allgemeinen Formel R_x-Si-A_4-x worin die Reste A gleich oder verschieden sind und Hydroxylgruppen oder hydrolytisch abspaltbare Gruppen darstellen, ausgenommen Methoxy, die Reste R gleich oder verschieden sind und hydrolytisch nicht abspaltbare Gruppen darstellen und x den Wert 0, 1, 2 oder 3 hat, wobei bei mindestens 50 Stoffmengen-% der Silane x ≥ 1 ist; unter den Bedingungen des Sol-Gel-Prozesses mit einer unterstöchiometrischen Wassermenge, bezogen auf die vorhandenen hydrolysierbaren Gruppen, unter Bildung eines Nanokomposit-Sols, gegebenenfalls weitere Hydrolyse und Kondensation des Nanokomposit-Sols vor dem Inkontaktbringen mit dem Substrat und anschließende Härtung, wobei das Substrat keine Glas- oder Mineralfaser ist und kein Pflanzenmaterial ist.

From the WO 98/22648 A2 there is known a composite material characterized by a substrate and a nanocomposite in functional contact therewith, which is obtainable by surface modification of

• a) colloidal inorganic particles with
• b) one or more silanes of the general formula R _x -Si-A _4-x wherein the radicals A are the same or different and represent hydroxyl groups or hydrolytically cleavable groups, except methoxy, the radicals R are the same or different and represent hydrolytically non-cleavable groups and x is 0, 1, 2 or 3, wherein at least 50 molar amounts -% of silanes x ≥ 1; under the conditions of the sol-gel process with a substoichiometric amount of water, based on the existing hydrolyzable groups, to form a nanocomposite sol, optionally further hydrolysis and condensation of the nanocomposite sol before contacting with the substrate and subsequent curing, wherein the substrate is not glass or mineral fiber and is not a plant material.

task The invention thus provides a method for transmitting of interference layers, holograms and other high-refractive elements to create optical microstructures on substrates that are also in the High temperature range is used.

• a) auf einer Trägerfolie wird eine flexible Trägerzwischenschicht als Release-Schicht aufgebracht,
• b) auf dieser Trägerzwischenschicht wird ein Prägesol appliziert und mit einer Oberflächenstrukturierung versehen,
• c) Herstellen eines Stapels, bestehend aus einer Bindemittelschicht und der Oberflächenstrukturierung,
• d) Entfernen der Trägerfolie,
• e) thermische Behandlung des Werkstückes.

This object is achieved according to the invention by a method for transferring surface structures, such as interference layers, holograms and other high-index optical microstructures, onto a substrate, comprising the following method steps:

• a) a flexible carrier intermediate layer is applied as a release layer on a carrier film,
• b) a embossing oil is applied to this carrier intermediate layer and provided with a surface structuring,
• c) producing a stack consisting of a binder layer and the surface structuring,
• d) removing the carrier film,
• e) thermal treatment of the workpiece.

It Thus, on a carrier film, a flexible carrier intermediate layer applied as a release layer.

On this carrier intermediate layer becomes the embossing oil, which have a sufficient refractive index difference to the adhesive should, applied and with a surface structuring, z. B. a hologram or other optical microstructure provided.

Subsequently a stack of a binder layer and the surface structuring is formed.

Then the carrier film is removed.

After all the workpiece is thermally treated, so that on End on the substrate surface only the structured high-index Stick layer by means of the binder layer.

With Such a transfer film may contain an interference layer, a hologram or other optical microstructure are transferred to a substrate, wherein the transferred layers are obtained in the transfer process remain so that a subsequent drying process and a furnace treatment in the high temperature range are possible.

The advantages of the invention consist essentially in the fact that a high-temperature-stable transfer film is created, the hot work materials or materials that are subsequently heated, applied and durable. This also means that the interference layers, holograms and other optical microstructures thereby applied can not be subsequently removed or damaged by thermal treatment. The transfer film can also be produced on a film coater with coupled embossing station in the form of film rolls and is thus suitable for mass production.

Consequently is it possible, for example, even on still hot Substrates to transfer a hologram or a hologram transferred to a substrate during the Use is heated to the high temperature range, for. B. one Engine block or a vehicle catalytic converter. This opens new possibilities, even those parts with security feature, for example, a testable hologram, to ensure counterfeit security.

The optical principle of the invention is based on a sufficient refractive index difference between the optical microstructure and the binder layer. This aspect allows a particular variability, since the hologram or the optical layer can be used in combination with the binder for controlling the optical effects. Thus, for example, high-temperature stable layer packages can be produced, which act as a total reflection or antireflection layer, or as a hologram. In this case, for example, only the surface of the relief hologram (or the optical layer) can be provided with a layer having an adequate refractive index or the hologram (or the optical layer) can be made entirely of the material with the appropriate refractive index. In this connection, it is of interest that the refractory index of the binder can be adjusted by using high refractive index nanoparticles instead of SiO ₂ nanoparticles.

Farther it is within the scope of the invention that in the case of relief holograms structuring by simple or thixotropic embossing he follows.

A thixotropic structurable material is for example from EP 1 248 685 B1 known.

A Embodiment of the invention is that in Step c) a binder layer applied to the substrate and is dried and then the surface structuring is transferred to the binder layer.

alternative it is also possible that in step c) the binder applied directly to the surface structuring and then transfer this stack to the substrate becomes.

• a) kolloidalen anorganischen Partikeln mit
• b) einem oder mehreren Silanen der allgemeinen Formel R_x-Si-A_4-x worin die Reste A gleich oder verschieden sind und Hydroxylgruppen oder hydrolytisch abspaltbare Gruppen darstellen, ausgenommen Methoxy, die Reste R gleich oder verschieden sind und hydrolytisch nicht abspaltbare Gruppen darstellen und x den Wert 0, 1, 2 oder 3 hat, wobei bei mindestens 50 Stoffmengen-% der Silane x ≥ 1 ist;

unter den Bedingungen des Sol-Gel-Prozesses mit einer unterstöchiometrischen Wassermenge, bezogen auf die vorhandenen hydrolysierbaren Gruppen, unter Bildung eines Nanokomposit-Sols, gegebenenfalls weitere Hydrolyse und Kondensation des Nanokomposit-Sols.It is within the scope of the invention that the binder consists of a nanocomposite which is obtainable by surface modification of

• a) colloidal inorganic particles with
• b) one or more silanes of the general formula R _x -Si-A _4-x wherein the radicals A are the same or different and represent hydroxyl groups or hydrolytically cleavable groups, except methoxy, the radicals R are the same or different and represent hydrolytically non-cleavable groups and x is 0, 1, 2 or 3, wherein at least 50 molar amounts -% of silanes x ≥ 1;

under the conditions of the sol-gel process with a substoichiometric amount of water, based on the existing hydrolyzable groups, to form a nanocomposite sol, optionally further hydrolysis and condensation of the nanocomposite sol.

at the process of the invention it is expedient the substrate has a glass surface, a ceramic surface or a metal surface.

As well it is advantageous that the carrier film is a polyethylene terephthalate film (PET) or a polyimide film.

It is advantageous in that the carrier intermediate layer a polyvinyl alcohol based film.

to Invention is also pertinent that in step e) the thermal treatment at temperatures up to 800 ° C, preferably at temperatures up to 450 ° C takes place.

After all Is also provided according to the invention that at the second alternative with respect to step c) in step e) transfer to a hot substrate, wherein the substrate temperature of about 80 ° C to 800 ° C, preferably from 100 ° C to 600 ° C and more preferably from 150 ° C to 450 ° C.

following The invention is based on drawings and an embodiment explained in more detail.

It demonstrate

1 a schematic representation of a transfer film for the inventive method,

2 a hologram structure after its fixation on a substrate.

How out 1 it can be seen, the transfer film used in the process according to the invention consists of a carrier film 1 which may be, for example, a polyethylene terephthalate or a polyimide film.

On this carrier foil 1 becomes a carrier interlayer 2 (or release layer), which contains in particular polyvinyl alcohol (PVA) and optionally additives, in particular fluorinated additives (eg zonyl) or similar acting additives, applied, with a layer thickness of about 40 microns applied, on which in turn a high-index layer 3 is applied. The carrier interlayer 2 is used because the adhesion between the backing layer 1 and the high refractive layer 3 would be too big.

In the high-refractive layer 3 a hologram structure is introduced.

By means of the inorganic binder 4 as it is from the WO 98/22648 A2 for producing a composite material, the transfer film is applied to a substrate 5 , which preferably has a glass, ceramic or metal surface, with the high-index layer to the substrate 5 Applied applied. The carrier foil 1 is from the carrier interlayer 2 removed before the thermal treatment. After curing of the binder layer 4 the fixing (burning out) takes place, so that at the end on the substrate only the structured high refractive index layer 3 by means of the binder layer 4 attached ( 2 )

The transferred structures remain with a periodicity of about 4 microns on an area of 1 cm ² during the transfer process, so that a subsequent drying process and a furnace treatment at temperatures of 450 ° C and in some cases up to 800 ° C is possible.

Embodiment:

1 Preparation of the brine

1.1 Glue - Sol

To submitted 327.5g methyltriethoxysilane and 95.5g tetraethyl orthosilicate are 142 g of silica sol Levasil 300/30 and 4 ml of a 37% HCl solution added with stirring. After cooling the Solution at about 15 ° C is a mixture of 327.5 g of methyltriethoxysilane and 95.5 g of tetraethyl orthosilicate of the reaction solution admix.

1.2 Embossing - Sol

To 22.43 g of isopropanol are 4.46 g of titanium isopropoxide with stirring to add quickly (part 1). To 22.43 g of 1-butanol 0.68 g of a 16.9% HCl solution was added with stirring (Part 2). Part 2 is to be added to Part 1 with stirring.

1.3 Release - Sol

To 36.50 g of an approximately 8 percent polyvinyl alcohol (PVA, Poval 235) in water solution are 4.22 g of isopropanol. To an aliquot of 38.56 g of the above PVA solution is a mixture of 0.16 g of diethylene glycol, 0.08 g of Zonyl FS-300 and a mixture consisting of 1.083 g of dist. Water with 0.007 g Tween 80 and this to mix.

2 production of the layer stack: release, embossable layer and structuring of the embossable layer

2.1 Preparation of the Release Layer

The Under the heading 1.3 described release sol is by a 400 μm knife gap on a PET carrier film applied and dried at 150 ° C for 20 min.

2.2 Production of the stampable coating

On the release layer will be that under the heading 1.2 described embossing sol applied by flooding.

2.3 Structuring of the stampable layer

By A silicone rubber stamp becomes a relief hologram in the wet Movie laid. With a load of about 1 kg per square centimeter for about 1 second the punch is to be pressed. After a rest period of The solvent is in the silicone rubber for 30 minutes diffused, so that the thus dried Prägeschicht a has sufficient strength and the silicone rubber stamp can be removed.

3 Transfer of the hologram to a substrate

3.1 Transfer of the hologram to glass

The glass substrate should be coated with the adhesive by dip coats at 1 mm / s. After evaporation of the solvent at RT for about 1 h, the headline 2 described structured layer stack are laminated to the glass substrate. Thereafter, the glass substrate for 8 h at 80 ° C, and to heat up to 450 ° C within 4 h. The temperature of 450 ° C is kept for 1 h, then the workpiece within 4 h to 20 ° C to cool.

3.2 Transfer of the hologram to ceramic

The Ceramic substrate should be coated with the adhesive (Dipcoating 1 mm / s). After evaporation of the solvent at RT for About 1 h may be the structured layer stack described under heading 2 be laminated to the ceramic. Thereafter, the ceramic substrate for 8 h at 80 ° C, and within 4 h at 450 ° C. heat. The temperature of 450 ° C is for 1 h, then the workpiece within 4 h to 20 ° C. cooling down.

3.3 Transfer of the hologram to stainless steel

The stainless steel substrate should be coated with the adhesive (dipcoating 1 mm / s). After evaporation of the solvent at RT for about 1 h, the headline 2 described structured layer stack are laminated to the stainless steel. Thereafter, the stainless steel substrate is at 80 ° C for 8 h, and heated to 450 ° C within 4 h. The temperature of 450 ° C is kept for 1 h, then the workpiece within 4 h to 20 ° C to cool.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 6766734 [0003]
• - US 6694885 [0003]
• US 6854386 [0003]
• US 5702805 [0004]
• US 5318816 [0004]
• - KR 2002/024286 A [0005]
• - JP 2004/358925 A [0005]
• - JP 2003/280498 A [0005]
• - US 5702805 A [0005]
• WO 98/22648 A2 [0006, 0035]
• - EP 1248685 B1 [0019]

Claims (9)

Method for transferring surface structuring, like interference layers, holograms and other high-refractive ones optical microstructures on a substrate, characterized by the following process steps: a) on a carrier film becomes a flexible carrier interlayer as release layer applied, b.) on this carrier intermediate layer a embossing oil is applied and provided with a surface structuring, c.) Producing a stack consisting of a binder layer and surface structuring, d) Remove the Carrier film, e) thermal treatment of the workpiece. Process according to claim 1, characterized characterized in that in the case of relief holograms the Structuring takes place by simple or thixotropic embossing. Process according to claim 1, characterized characterized in that in step c) a binder layer applied to the substrate and dried and then transfer the surface structuring to the binder layer becomes. Process according to claim 1, characterized characterized in that in step c) the binder directly on applied the surface structuring and then this stack is transferred to the substrate. A method according to claim 1, characterized in that the binder consists of a nanocomposite obtainable by surface modification of a) colloidal inorganic particles with b) one or more silanes of the general formula R _x -Si-A _4-x wherein the radicals A are the same or different and are hydroxyl groups or hydrolytically removable groups represent the radicals R are the same or different and represent hydrolytically non-cleavable groups and x is 0, 1, 2 or 3, wherein at least 50 mole% of the silanes x ≥ 1; under the conditions of the sol-gel process with a substoichiometric amount of water, based on the existing hydrolyzable groups, to form a nanocomposite sol, optionally further hydrolysis and condensation of the nanocomposite sol. Process according to claim 1, characterized characterized in that the substrate is a glass surface, a Ceramic surface or a metal surface is. Process according to claim 1, characterized in that the carrier film is a polyethylene terephthalate film or a polyimide film. Process according to claim 1, characterized characterized in that in step e) the thermal treatment at temperatures up to 800 ° C, preferably at temperatures up to 450 ° C takes place. A method according to claim 4, characterized characterized in that in step e) the transmission on a hot substrate, wherein the substrate temperature from about 80 ° C to 800 ° C, preferably from 100 ° C to 600 ° C and more preferably from 150 ° C to 450 ° C is.