EP2212466A1

EP2212466A1 - Method for dying and/or printing adhesive closure parts

Info

Publication number: EP2212466A1
Application number: EP08802854A
Authority: EP
Inventors: Jan Tuma; Konstantinos Poulakis
Original assignee: Gottlieb Binder GmbH and Co KG
Current assignee: Gottlieb Binder GmbH and Co KG
Priority date: 2007-11-20
Filing date: 2008-10-10
Publication date: 2010-08-04
Anticipated expiration: 2028-10-10
Also published as: ATE533888T1; DE102007055428B3; PL2212466T3; JP5399405B2; WO2009065466A1; US8945685B2; CN101855399B; JP2011502769A; CN101855399A; US20100239780A1; EP2212466B1

Abstract

A method for dying and/or printing adhesive closure parts (10) having a plurality of hooks (12) predominately made of a plastic material connected to a carrier (14), applies a dye medium to the surface (16) of the adhesive closure part (10) or its parts by an application unit (18). Because the dye used is based on a solvent free wax applied by the application unit (18) in a melted form in droplets, bubbles, or pellet form, and enters into a fixed connection to the surface (16) in the cooled, cured state, a wax dye application may be achieved that is markedly colorfast and UV resistant.

Description

Process for dyeing and / or printing adhesive closure parts

The invention relates to a method for dyeing and / or printing adhesive closure parts with a plurality of entanglement means connected to a carrier, mainly consisting of a plastic material, wherein a color medium is applied by means of an applicator on the surface of the adhesive closure part or its parts.

These, usually tape-like fastener parts are freely available in a variety of embodiments on the market. The known adhesive closures consist regularly of two parts in the form of male or female engaging parts, the male engaging parts are formed from a hook or mushroom-shaped closure material as interlocking means, where female engaging parts can be set in the form of a hook or Velcro material, if the two Eingreifteile be joined together to form the actual adhesive closure. The pertinent interlocking means can be separated from each other again and again and connect with each other and main applications for patches are regularly found in the clothing industry; but are also the subject of technical applications, For example, as a fastener for wall or panel panels in vehicles and the like.

The tape-like adhesive closures mentioned can be obtained in one piece from plastic material by conventional shaping methods; However, it is also possible to obtain at least parts of these adhesive closures by weaving and / or knitting from a plastic fiber material. The plastic material used is usually colorless or has a colored base shade which originates from the extrusion process, which makes it difficult on a regular basis to adapt the finished adhesive closure products to color conditions, as is the case, for example, with the textile dyes in the clothing and textile industry result. In particular, if only small quantities of adhesive closures of a certain color are required, it causes difficulties for the manufacturer, the overall production process for a small one

To provide batch with a predetermined color of the plastic material.

In order to counter this, EP 1 502 988 A1 has already proposed to dye and / or print adhesive closure parts, which predominantly consist of plastic material, by means of inking nozzles, the output of solvent-containing ink being driven by a piezocrystal. In this way, very small color volumes, which lie in the pictoliter range, can be applied dropwise to the respective engaging part of the adhesive tape closure with a very fast application frequency. Starting from a colorless, preferably transparent base material or one with a basic coloration, color design tasks can be achieved in the extended frame. Depending on the color selected, even small amounts of engaging parts can be treated in terms of color and design. Furthermore, it is also possible to use the respective inking nozzle to realize a specific color design pattern on the engaging part, so that also Characters in the form of numbers or letters can be applied. In particular, it is possible with the known method solution to dye or produce small quantities of sealing material without the other production process being hindered for the engaging parts, that is to say for the agents.

As applied colors, in the known solution, inks, in particular reactive inks, acid inks or dispersion inks are used. The pertinent inks are solvent-containing, so that they are not particularly suitable for labeling adhesive fastener parts used in the food, cosmetics and pharmaceutical industries. Also, it has been found that, especially in a very long-lasting operation with numerous washes, the ink used bleaches, which reduces the clarity of ink application over time and leads to an unsightly appearance. Also, the inks are often not as lightfast and then bleach under the sun exposure accordingly strong.

Furthermore, a method is known from WO 98/39 759 AI, are used in the dyeing and / or printing of fastener parts solvent-based inks, curable inks and water-based inks as a color medium. US Pat. No. 6,910,353 B2 uses water-based inks with acrylate binders, which are applied by means of flexographic printing processes, for a comparable purpose of use. From DE 698 13 17712 it is known to use solvent-free waxes in the form of hot-melt ink compositions for printing on porous substrates for creating so-called barcodes.

Based on the above-mentioned prior art, the object of the invention is a process for dyeing and / or printing of adhesive fastener parts which, while retaining the advantages of the known dyeing solutions, further improves these in such a way that they remain colourfast even in the long-term operation and that also increased environmental and health requirements are taken into account. This object is achieved by a method having the features of claim 1 in its entirety.

Characterized in that in the inventive method as a color medium such is used on the basis of a solvent-free wax, which is applied melted in droplet, blister or pellet form by means of the applicator and in the cooled, cured state, a firm connection with the surface of the adhesive closure part together with its parts, even the smallest quantities of adhesive closure parts can be reliably colored or printed by process technology, whereby the paint applied has turned out to be remarkably wash-proof and UV-resistant, even after very long periods of use.

In the context of the wax application, the process according to the invention does not involve any solvents, so that even in critical areas, such as the food industry, the pharmaceutical or cosmetics industry, the wax-colored adhesive closure part can be readily used for special products, such as packaging. Starting from a preferably colorless, transparent plastic material or a plastic material with a basic coloring, color design tasks can be solved in a wide frame by applying the wax. The wax application is very reliable and it makes economic sense to treat even small amounts of adhesive closure parts color and design. In addition to the order of a color design pattern, the application waxes can also be applied in the form of numerical or letter sequences, so that in this respect also manufacturer information, product information or the like can be attached to the adhesive closure part. The application device for the color wax is preferably at least one Wachsauftragdüse, the output of wax is controlled by a piezoelectric crystal stall. In this way, very small wax volumes, which lie in the pictoliter range, can be applied drop by drop with a very fast application frequency to the adhesive closure part together with its parts. Another possibility is to provide the color wax in the manner of single wax rods, which are melted in the device interior of the applicator and then fed to a print head of the same. The printheads then inject the application wax, such as pellets, onto the surface of the respective fastener part. In this order method, the color wax when hitting the adhesive closure part is already almost solid again, which has the advantage that especially in tissue-like adhesive fastener parts made of individual filaments, the wax does not completely penetrate into the tissue to fade in such a way.

Another option is to suddenly heat the color wax to its evaporation temperature (> 300 ⁰ C), with the result that the wax forms bubbles, which in turn can collapse and thereby be thrown explosively from an application nozzle. This process can be repeated up to 10,000 times per second and also in such a way can be a high-quality printing process for the respective fastener part reach. As best manageable, however, has already been mentioned at the beginning Piezoauftragtechnik. The paint application wax dries in fractions of a second on the surface of the fastener part, so that any post-drying or post-curing operations are not necessary, which in turn increases the process speed. In a preferred embodiment of the method according to the invention, each color wax application nozzle used for a particular color or hue is used, with mixed colors can be generated directly on the surface of the fastener part by means of different wax applicator. However, it is also possible to supply mixed colors directly to the product via the respective wax application nozzle and to dye it in this way. In order to obtain high Einfärbe- or printing speeds, a plurality of wax applicator nozzles may be provided, preferably the wax applicator nozzles are arranged fixed in the applicator and inked or to be printed adhesive fastener parts are fed at a predeterminable speed through the applicator and by means of the wax applicator with the paint Mistake.

Acrylates which have proven to be readily inkable plastic materials as well as customary polyamide, polyester, polyethylene and polypropylene materials from which otherwise the interlocking means of the band-like adhesive closure parts are obtained in one piece as a cast product or by customary knitting weaving methods.

In a further development of the method according to the invention, it can preferably be provided to provide the wax application nozzles on both surfaces of the adhesive closure part that are opposite one another, so that a dyeing or printing process can take place from two different sides, optionally with different waxes and colors. It has also proven to be particularly advantageous to supply the adhesive closure parts before the actual dyeing or printing with the wax to a reactive pretreatment in the sense of a surface coating or a surface functionalization to increase the color depth. In the following the process of the invention for dyeing and / or printing adhesive closure parts will be explained with reference to an embodiment of the drawing. In principle, and not to scale, the sole figure shows the essential components of a Wachsauftragdüse for coloring a band-like adhesive closure member with male engaging parts in the form of fungal Verhakungs- medium, wherein the wax is applied to the rear surface of the adhesive closure part.

The inventive method is used for coloring and / or printing of fastener parts 10, wherein in the figure as so-called. Male Verha- kmittel 12 mushroom-like hooking heads are shown, which are integral part of the belt-like support 14 for the fastener part 10. The mushroom-like interlocking elements 12 can be connected to a corresponding hook or loop material as a so-called female engaging part to form an adhesive closure system (not shown), the hook or loop material releasably engaging the peripheral projections of the interlocking elements 12. A manufacturing method for such engaging parts is described by way of example in the Applicant's EP 1 309 257 B1. Furthermore, the adhesive closure part consists in this respect of a cast in a sieve plastic material, for example in the form of polyethylene in colorless design and thus almost transparent or the plastic material is provided with a base color, as it results from the plastic granules, from which the adhesive closure member 10 via the said known extrusion process can be produced. Instead of the molded in the so-called chill roll adhesive closure member 10, this may also consist of a woven or knitted support base structure, from which the interlocking means (hooks, mushrooms, loops, etc.) with a predetermined projection then protrude (not shown). O

If you want to dye or print a pertinent, preferably ribbon-like adhesive closure part 10, it is not enough to master the multitude of design tasks, to color the plastic granulate in advance, ie before the actual adhesive closure part 10 is produced, but it is desirable to later manufacture the already produced one Dyeing and printing adhesive closure part made of plastic material, in particular taking into account that often only small quantities (strips of less than 1 m length) of the hook closure part 10 with a certain color design, for example for use in the clothing or packaging industry, needed. In the present case, as shown in the figure, the rear surface 16 of the adhesive closure part 10 is inked or printed accordingly.

In order to meet the above-mentioned requirements, the method according to the invention provides for the inking and / or printing of the adhesive closure part 10 by means of at least one wax applicator nozzle 18. The ejection of the wax application nozzle 18 of color wax is controlled by a piezoelectric crystal 20, such an output of color wax per activation cycle of the piezoelectric crystal 20 being in the range of the picolitre. Since Piezokristal- Ie 20 but known to have very high vibration frequencies, the small order quantity is sufficient to achieve a rich color wax application, depending on the used Kunststoffmateri- as for the adhesive closure member 10 is also the possibility that at least partially applied wax application in the Plastic material slightly penetrates the surface side and in such a way saturates the open pores of the plastic material with color wax.

For the sake of simplicity, only one wax applicator nozzle 18 is shown in the figure; However, a large number of nozzles is necessary for a noticeable dyeing or printing process, wherein a plurality of color wax applicator nozzles 18, for example 100 to 200 pieces in one Printhead of the overall application device (not shown), can be recorded and with 10 to 20 such piezo-driven printheads can then achieve a high throughput speed along with full color wax application for the adhesive closure part 10 on the rear surface 16 with very high printing speeds. Depending on the selected control for the piezoelectric crystals 20 there is also the possibility of not only undertaking inking processes but also of providing the respective adhesive closure part 10 with a printed pattern, also in the form of an advertising inscription, company name print or the like. Instead of the adhesive closure part 10 shown, it is also possible for such to occur with hook-shaped closure heads or a female engagement part in the form of a conventional loop or loop closure material (not shown), wherein the engagement elements in question can also be obtained via the already mentioned weaving process.

Instead of the treatment of the rear surface of the adhesive closure part 10, this can of course also on the opposite upper side in the region of the free end faces of the interlocking means 12 provided with an application of paint by means of the order wax. This also applies to the respective stem material or the free distances between the mushroom-like adhesive closure parts 12. A particularly beautiful undisturbed shaping image results from the backward printing according to the embodiment of the figure.

The inking nozzle 18 shown in the figure is formed overall in the manner of a capillary nozzle and this is in fluid communication with a pressure chamber 22 in connection, on the upper side of a vibrating plate 24 acts, which is controlled by the piezoelectric crystal 20. Positive and negative voltages are thus applied to the mentioned piezoelectric crystal 20 in order to control the wax release. If there is no voltage at the piezocrystal 20, the color wax flows into the pressure chamber 22 from a storage chamber (Not shown) originating via the supply line 26 into the pressure chamber 22 a. If a voltage is now applied to the piezocrystal 20, the crystal pushes over the vibrating plate 24 to the wax color in the pressure chamber 22 and hurls the color wax through said capillary nozzle 18 on the rear surface of the adhesive closure part 10. By applying a negative voltage to the Piezo crystal 20 then moves the vibrating plate 24 abruptly, whereby the color wax application is interrupted abruptly. Due to the extremely fast voltage change, the delivered amount of wax can be very finely dosed, so that can be achieved with the pertinent application method resolutions of 100 to 9600 dpi, preferably up to several 10,000 dpi. As a result, a very good printing and wax color quality is achieved.

The mentioned inking and printing process by means of the color wax can be operated quasi-continuously and coming from the manufacturing machine, the adhesive closure member 10 can be continuously passed under the color wax application device, whereby by meaningful control of the piezoelectric crystals 20 and by a suitable choice of Wachsfarb- the Change color and print design during the pass process. As applied color wax, in particular those have proved to be advantageous, which are solvent-free. Furthermore, colored waxes are used, which are preferably kneadable at 20 ⁰ C and otherwise hard until brittle hard. The wax used in each case should have a coarse to fine crystalline structure, be colored translucent to opaque in its color design; but not glassy. 40 ⁰ C, the colored wax used should melt without decomposition and therefore be a little bit viscous liquid slightly above the melting point. In particular, a strong temperature-dependent consistency and solubility has proven to be favorable, and if the color wax used can be polished under light pressure, this enables a post-treatment possibility in which modify the surface design of the wax, for example, that the applied to the fastener part wax appears shiny. In terms of a post-treatment, it is also possible to fix the wax, for example by the applied wax subsequently with water vapor and / or with an alkaline cold bath and / or by mechanical treatment, for example by means of a pressure calender, which presses on the bewachste surface of the adhesive closure part 10 , is additionally fixed. Furthermore, aftertreatment can also be carried out by means of IR or UV light or by the introduction of intrinsic energy. Furthermore, it is possible to post-actinize the closure product by means of actinic energy.

In order to achieve a particularly good adhesion of the color wax used in each case on the assignable surface of the adhesive closure part 10, a process for surface functionalization of the adhesive closure member 10 may be upstream of the actual color wax application. In particular, by using a proton and / or electron exchange medium, in particular in the form of donors or collectors, the surface energy of the adhesive closure part 10 can be modified using high energy such that coating-free and aging-resistant the chemically physical properties of the adhesive closure material can be adjusted are by attaching functional groups of the exchange medium to the fastener part material. The pertinent attachment process of the functional groups to application wax can be supported by means of high energy influence, for example by using high-frequency radiation, electric fields, such as the di-electric barrier discharge, or by means of plasma-assisted fields. In particular, substances and substance groups according to the following listing serve as proton and / or electron exchange media:

P, Cl, N ₃ , Br etc. The pertinent exchange media interact particularly well with the plastic material for the respective adhesive closure part 10, provided that the plastic material belongs to one of the following groups: polyethylenes, polypropylenes, polybutenes and polyisobutenes and poly (4-methyl-1-pentene) s, polymers of higher α Olefins, eg poly (I-hexene), poly (I-octene) or poly (I-octadecene). Copolymers of different olefins, for example those of ethylene with propylene, should also be recognized as belonging to the corresponding polyolefins. Another good starting material for the adhesive closure parts to be produced is polyester. If the plastic material used in each case is surface-functionalized with the proton and / or electron exchange medium mentioned, a particularly good bonding of the respective application wax to the surface 16 of the adhesive closure part 10 is to be expected, the change in surface energy thus obtained for the adhesive closure part 10 within the surface 16 takes place and does not present itself as a coating.

Another way of surface activation for the plastic material of the adhesive closure member 10 is to actually apply a coating to said surface 16, for example in the form of fluorine. In particular, the fluorine application has proven to be favorable for the subsequent adhesion of the color wax on the adhesive closure part 10. By the use of fluorine some of the plastics mentioned for the adhesive closure member 10 are attacked on its surface and taking advantage of this effect can be specifically the surface 16 of the adhesive closure part 10 for the addition of the color wax modify. To increase the depth of color, provision may also be made for the surface 16 to be fed to a reactive cationic pretreatment in the sense of a surface modification or additionally to apply so-called hydrotrope substances. With the method according to the invention even the smallest amounts of adhesive fastener parts 10 can be permanently dyed or printed with the color wax, whereby the pending color wax application or entry has proven to be particularly wash-resistant and UV-resistant even in long-lasting operation.

Claims

Patent claims

1. A method for dyeing and / or printing adhesive closure parts (10) with a plurality of Ver¬ with a carrier (14) associated Ver- kung means (12), mainly consisting of a plastic material, wherein a color medium by means of an applicator (18) on the surface (16) of the adhesive closure part (10) or its parts, characterized in that the color medium used is one based on a solvent-free wax which has been melted down in droplet, blister or pellet form by means of the application device (18 ) is applied and in the cooled, cured state enters into a firm connection with the surface (16).

2. The method according to claim 1, characterized in that the wax application by means of the applicator (18) takes place such that already upon impact of the wax on the surface (16) of the adhesive closure part (10) this is almost again solid or cured.

3. The method according to claim 1 or 2, characterized in that are used as color waxes those that meet at least the following criteria:

- Kneading at 20 ⁰ C, solid to brittle hard, has a coarse to finely crystalline structure, - color is translucent to opaque, but not glassy, over 40 ⁰ C melts without decomposition, slightly above the melting point slightly liquid (little viscous),

- Has a strong temperature-dependent consistency and solubility and - is polishable under light pressure.

4. The method according to claim 3, characterized in that the color waxes used are those which are esters of higher, even-numbered fatty acids (C16 to C18) with higher fatty alcohols (C16 to C36).

5. The method according to any one of claims 1 to 4, characterized in that the surface (16) of the adhesive closure part (10) or parts thereof are functionalized for better adhesion of the color wax and / or that the surface (16) insofar with an active coating is provided.

6. The method according to any one of claims 1 to 5, characterized in that the applicator has at least one Wachsauftragdüse (18), the output of wax is controlled by a piezoelectric crystal (20).

7. The method according to claim 6, characterized in that each Wachsauftragdüse (18) is used for obtaining a particular color or hue and that mixed colors are supplied by means of different wax application nozzles (18), the order of the mixed colors directly on the surface (16) of the adhesive closure part (10).

8. The method according to any one of claims 1 to 7, characterized in that the wax coating on the surface (16) of the carrier (14) of the

Adhesive closure part (10) is caused, which is the Verhakungsmitteln (12) of the adhesive closure part (10) facing away.

9. The method according to any one of claims 1 to 8, characterized in that a fixation or aftertreatment of the on the surface (16) of the adhesive closure part (10) applied wax by means of a fixing or polishing agent, or by applying intrinsic or actinic energy and by means of UV or IR light.