EP1138525A1 - Phosphorescent, printable media - Google Patents

Abstract

The invention relates to a phosphorescent material, comprising a support layer and a phosphorescent ink-receiving layer. Said material can be printed or inscribed using transfer methods for digital data, especially relating to images and text.

Description

The present invention relates to a phosphorescent Material made using transfer systems resp. Transfer procedures for digital data, in particular Images and texts, such as laser lettering and in particular Ink-jet printer that can be labeled and printed on. Such Transfer systems resp. Transfer procedures or transfer technologies are subsequently called digital image transfer systems resp. -Procedure -technologies.

There are already coatings with phosphorescent Material known, e.g. Coatings for Textiles, bicycles etc. Increase such coatings the visibility of the appropriately coated objects in the dark. They are usually using printing processes such as screen printing, etc. applied.

The stand's phosphorescent layers technology have various disadvantages. Since the phosphorescent materials under light irradiation show only slight intrinsic color, their contrast is on light background, e.g. during the day or in a well lit area Space, very small. In addition, such layers usually applied by screen printing, i.e. every "motif" needs an appropriate template. At Combination of phosphorescent materials with usual Colors do not have the disadvantage of poor contrast on a light surface when exposed to light but different colors require a corresponding one Number of stencils.

Become phosphorescent layers alone e.g. applied to a light t-shirt, so they are with Hardly to see days. Such a t-shirt has little appeal for people who are not alone in the dark well visible image resp. a visible lettering want her t-shirt. Furthermore, due to the previous order process used an individual design not possible or only to a very limited extent. Individual Design of e.g. T-shirts are in high demand. materials and methods for individual design and Manufacture of T-shirts are known, e.g. from EP 0 850 786. These state-of-the-art t-shirts are available in Darkness not visible.

Even with labels that indicate in the dark are the existing labeling procedures only of limited suitability since the production of printing stencils is only worthwhile for large quantities, so that individually optimized labeling is hardly possible or is very expensive.

The aim of the present invention was therefore to one with digital printing process, respectively. corresponding Techniques printable resp. writable phosphorescent Provide material.

This goal was achieved through the provision of a phosphorescent material, the one Carrier layer and a color receiving layer includes and which is characterized in that the ink receiving layer contains a phosphorescent pigment.

Surprisingly, it was found that a material according to the invention has good ink receptivity and the phosphorescence of such a layer through the digitally applied layer of paint can be covered, making a clear in the dark A light-dark picture emerges.

The ink receiving layer can be a homogeneous Layer or from layers lying on top of each other be built up, with a sub-layer, preferably the the sublayer closer to the support, the phosphorescent Contains pigment.

So that the digitally applied image, for example a color image applied by means of laser or inkjet printing or lettering, is clearly depicted, ie shows a good resolution, it is advantageous if the ink-receiving layer comprises porous solid particles in a binder. Such porous particles are, for example, ceramic parts, such as zeolites, or plastic particles, it being possible for such particles to be obtained directly by a special production process or by subsequent shrinking or agglomeration. Preferred porous particles are porous, solid thermoplastics. Such particles preferably have a specific surface area of> 6 m ² / g, in particular 20 20 m ² / g, a particle size of 0.1-40 μm, in particular 5-15 μm, and a melting temperature of <200 ° C. Thermoplastics such as the products known under the name Orgasol, in particular Orgasol® 3501 from, for example, Elf Atochem, Pouteaux, France, with a particle diameter of approximately 10 μm and a surface area of approximately 25 m ² / g are particularly preferred.

E.g. Ceramic particles used like Zeolite, these are preferably in combination with porous solid thermoplastics such as Orgasol® 3501.

The ink receptive layer is made up of partial layers constructed, 2 sublayers being preferred, see above deep-melting porous particles are strongly preferred because these become transparent when they melt. Such porous Particles can either only in one sub-layer, preferably the sublayer without phosphorescent Pigment, or be present in both sub-layers.

The presence is for quick color absorption porous particles in the layer facing away from the carrier prefers.

Suitable as a phosphorescent pigment non-radioactive, long phosphorescent pigments, such as they e.g. in EP 0 622 440 = US 5,424,006 and e.g. by Nemoto (Europe) B.V. in Amsterdam NL at the name LumiNova® are available. Be used they usually in amounts of 5-60%, preferably in Amounts of approximately 35%. Such pigments phosphoresce in the generally at least 3 hours, often up to 8 hours.

It is additionally preferred if not only that Solid particles in the ink receptive layer, but instead the binder is also porous. Increased by such Porosity can local fluid intake, be it ink or pigment melt, increase what a better penetration of the entire layer with pigment and clear contours. A manufacturing process a porous binder layer is e.g. from EP 0 850 786 known.

The binder can be a thermoplastic Resin, if necessary after heating once and activation further networked or one already complete cross-linked, thermosetting resin. The choice of suitable binder, e.g. according to the purpose of the printed resp. labeled according to the invention Materials.

Preferred binders, especially for Transfer materials include polyvinyl alcohols, polyvinyl acetates, Polyvinylpyrrolidones, cross-linked, linear polyurethanes and especially preferred polyamides for which Transfer to e.g. Cotton t-shirts, especially thermoplastics with melting point <200 ° C, especially <140 ° C.

The ink-receiving layer usually has a proportion of binder of 10 to 90% by weight, preferably 20-70% by weight, particularly preferably approximately 30% by weight, of porous particles of 5 to 85% by weight, preferably approximately 35 wt .-% and phosphorescent pigment from 5 to 60 wt .-%, preferably about 35 wt .-%. It is applied to the support in amounts of (in the dried state) 5 to 80 g / m ² .

The phosphorescent according to the invention Materials include transfer layers, e.g. for the Transmission of images, i.e. the ink receptive layer, on a substrate. Such substrates are e.g. Fabrics, knitted fabrics, Nonwovens, especially textiles like T-shirts, however also objects such as doors, bicycles etc. In addition to the Transfer layers comprise the phosphorescent layers according to the invention Materials also "fixed" materials, i.e. Materials with the ink-receptive layer on the Carrier layer remains.

Fixed materials are relatively uncritical and can be a variety of different substrates , provided that their flexibility and the Liability of the ink absorption layer for the implementation of the Printing process is sufficient. To increase liability can optionally be a surface treatment of the carrier or an adhesion promoter layer between the carrier and the ink receiving layer can be provided.

With fixed materials, there is also the ink absorption layer, especially the binder critical as long as there is sufficient access to the porous Solid particles allowed. To add the color pigments to fix it may be advantageous be a e.g. thermally post-crosslinking thermoplastic To use binders that melt the porous particles loaded with color pigments and at least partially "sealed". It lies of course also in the context of this invention printed resp. labeled ink absorption layer through subsequent application of a cover, e.g. a slide, secure against mechanical damage, e.g. at Use as signs, such as floor labels, fittings or keyboard names etc.

Other applications put under this Materials referred to as transfer materials ahead, with at least the ink-receptive layer on a substrate, e.g. a textile that is transferred.

Non-phosphorescent transfer materials are known and described for example in EP 0 850 786. Such layer systems are basically also for the phosphorescent materials of this invention are suitable provided they are porous in the ink-receptive layer Contain solid particles, so this layer with phosphorescent pigment can be provided without that problems with only partial coverage of the Phosphorescence through the applied image resp. the angry one Lettering is achieved. A "show through" The phosphorescence could be the clear statement of the dark visible image affect what in particular with important inscriptions, e.g. of emergency exits, could have undesirable consequences.

Such transfer materials must have sufficient flexibility and sufficient adhesion of the ink-receiving layer to the support layer during printing or. Labeling also have good transfer properties, ie, for example, good removability of the carrier layer after heat treatment, for example ironing or hot lamination of the transfer material lying on the substrate with the ink-receptive layer, for example a textile. This separation of carrier and ink-receiving layer can be improved, for example, by a release layer between the carrier layer and ink-receiving layer, for example a silicone layer and / or a layer of a low-melting thermoplastic polymer, such a release layer of a low-melting thermoplastic polymer simultaneously providing a protective film over that on a substrate trained transfer ink layer and stabilize it. A release layer made of a deep-melting thermoplastic polymer has a melting point which corresponds approximately to the melting point of the binder in the ink-receiving layer. The release layer is usually applied in amounts of 5 to 50 g / m ² (based on dry substance).

A carrier material preferred for the transfer system is a siliconized paper on one side with a basis weight in the range of 50-150 g / m ² .

These are preferably transferred to a substrate Layers breathable so that this is the wearer especially during sporting activities, such as cycling, Running, hiking, but also when dancing, do not interfere.

The phosphorescent ink absorption layer can be easily made by powdered phosphorescent pigment with the other components the ink-receiving layer or a partial layer of the ink-receiving layer mixed and the resulting mixture to an optionally pretreated or pre-coated Carrier applied by the usual method becomes.

The use of the phosphorescent materials the present invention is very versatile. As already mentioned, these can be used for signaling e.g. Emergency exits, fire extinguishers etc. are used, but also for the designation of operating systems, their Safe operation also important, or especially in the event of a power failure is.

Another possible use is with Printing on textiles given, especially in their individual design, where by applying phosphorescent "White areas" in addition to the previously applied materials obtained aesthetic effect in a bright environment also an aesthetic effect in the dark or e.g. is achieved in a discotheque. At the same time is the carrier by the phosphorescence bad light made more visible, leading to that Security, e.g. as a pedestrian on poorly lit. Roads or paths.

The invention will now be illustrated by examples explained in more detail.

Example: Substances used:

1. Preparation of a binder solution for a porous hot melt layer: A polyamide, e.g. Elvamid, is in a mixture dissolved by water and ethanol or water and methanol. For later dispersing of the microporous Particles and the phosphorescent pigment and stabilization the standing dispersion can additionally be a Typical dispersing agent for organic fillers be stirred. The concentration of the polyamide in the Solution should be about 10 to 90 wt .-% and the mixing ratio Water / alcohol is adjusted in such a way that when coating the viscous binder solution on a carrier and then drying form approximately 60-80 ° C porous layers.

2. Microporous particles: polyamide powder, for example Orgasol 3501 (grain size approximately 10 microns, specific surface area approximately 25 m ² / g).

3. Phosphorescent pigment: Non-radioactive, phosphorescent pigment in powder form, for example Luminova G 300.

4. Diluent: Water / alcohol in the same mixing ratio as above.

5. Aqueous dispersion for applying the Hot melt layer (primer): A dispersion based on a sealable Ethylene-acrylic acid copolymer, for example a Enorex type with a solids content of approximately 40%.

Example 1: Production of a transfer film:

In a first step, the dispersion for the hot melt layer (release layer) is applied to the silicone side of a one-sided siliconized adhesive paper (120 g / m ² ) by means of a coating process, for example reverse roll, and then dried at a temperature of approximately 110 ° C. The dry application should be approximately 30 g / m ² . In a second step, the dispersion is prepared for the porous hot melt layer (ink absorption layer). Using a stirrer, portions of the polyamide powder (point 2), the phosphorescent pigment (point 3) and the diluent (point 4) are alternately stirred into the binder solution (point 1) under dispersing conditions until a coating of suitable viscosity that can be coated with coating methods, e.g. Reverseroll, is mixed arises. Alternatively, the polyamide powder (point 2) and the phosphorescent pigment (point 3) can be mixed in advance and this mixture can be stirred in in portions, alternating with the diluent (point 4). The dispersion for the porous hot melt layer (ink absorption layer) is then applied to the hot melt layer (release layer / 1st step) by means of a coating method, for example reverse roll, and is dried at a temperature of approximately 60-110 ° C. The dry application should be about 30 g / m ² . The solids content of the binder, based on the porous hot melt layer, is preferably around 30% by weight, the proportion of microporous particles is around 35% by weight and the proportion of phosphorescent pigment is around 35% by weight.

Such a layer has a good mechanical Stability and porosity and can be done with digital Print and label image transfer systems well, but it can also be used with common painting aids such as aqueous and solvent-based crayons, water colors and wax crayons similar to ordinary paper be painted.

The transfer to a substrate like white and colorful cotton t-shirts are done with the iron about 160 ° C to 200 ° C (heat setting for cotton). The hot melt material is printed with the resp. labeled Put the side against the T-shirt and the desired one Position. With the iron, the paper back brushed thoroughly under strong pressure so that the color can fuse with the layer and this combines with the fabric. When the hot The paper back has cooled down a bit, the adhesive paper deducted. Then several can Washing processes in a washing machine with common detergents be performed. The phosphorescent pigment and the colors showed good fastness to washing.

Analogously, the transfer can also be carried out using a hot laminator on e.g. a large-area textile, e.g. on Banner, done.

Example 2: Production of a "Fixed" Material:

The procedure is as described in Example 1, the ink-receiving layer directly (without release layer) is applied to the carrier. There with no transferability required for a "fixed" material is, the material used as a carrier does not need the To have separation-promoting layers, e.g. one to this Purpose of not using siliconized paper, Rather, depending on the requirements, an adhesion promoter can be used.

Claims (14)

By means of printing techniques resp. Labeling techniques for digital data, in particular data from images and texts, printable and inscribable material with a carrier layer and an ink absorption layer which contains porous solid particles and a binder, characterized in that the ink absorption layer also contains a phosphorescent pigment. Material according to claim 1, characterized in that the porous particles have a particle size of 5-40 µm, in particular 5-15 µm, and a surface area of ≥ 20 m ² / g. Material according to claim 1 or 2, characterized in that the ink-receiving layer consist of a uniform layer. Material according to claim 1 or 2, characterized in that the ink absorption layer consists of at least two and preferably two sub-layers. Material according to one of claims 2 to 4, characterized in that the porous particles are made of thermoplastic material. Material according to claim 5, characterized in that the porous particles are made of polyamide, have an average diameter of approximately 10 µm and a surface area of 25 m ² / g. Material according to one of claims 1 to 6, characterized in that the binder is a thermoplastic binder. Material according to one of claims 1 to 7, characterized in that the binder is porous. Material according to one of claims 1 to 8, characterized in that the phosphorescent pigment is a non-radioactive pigment with at least 3 hours of phosphorescence. Material according to one of claims 1 to 9, characterized in that it has a release layer between the carrier layer and the ink-receiving layer which melts at a temperature which corresponds at most to the softening temperature of the binder in the ink-receiving layer. A method for producing a material according to any one of claims 1 to 8, characterized in that the phosphorescent pigment is mixed with the other constituents of the ink-receiving layer or a partial layer thereof and is applied to the carrier layer optionally provided with a release layer. Use of the material according to one of the Claims 1 to 10 as a mark. Use of the material according to one of the Claims 1 to 10 for printing on substrates. Use according to claim 13, characterized in that the substrate is a woven, knitted or nonwoven, in particular a textile.