CN1273200A - Adhesive tape with safety characteristic, manufacturing method thereof and use in packing material thereof - Google Patents

Abstract

A multi-ply pull-tab that incorporates security features. The pull-off tape comprises: an oriented support layer in the form of a film having microscopic images; a sealing layer bonded to the surface of the support layer; and optionally a release layer bonded to the The other surface of the supporting layer. The zip tape is suitable for use in conjunction with packaging materials. Also disclosed is a production method for the pull-off tape.

Description

Pull-away tape with security features, method of manufacture and use in packaging materials

This invention relates to the use of pull-tab tape and its security features on consumer goods, food packaging and the like.

The production and sale of counterfeit items is a growing problem. Such counterfeit products are often packaged in a deceptive manner similar to the genuine product, thereby deceiving would-be consumers into believing that the product they are buying is genuine. This creates various problems. On the one hand, the business of the manufacturer of the authentic product is affected. On the other hand, the intellectual property rights of the owner of the rights to the product are defrauded. What's more, in many cases, counterfeit products are of poor quality and can cause unimaginable damage to the image of the manufacturer. Poor quality also increases product reliability complaints, forcing the manufacturer of the genuine product to prove that the product that caused the loss did not come from the genuine manufacturer. Therefore, it is necessary to mark the genuine product, so that consumers can identify the genuine product, and in the event of accidental damage, it can prove that the product is genuine.

One known method of providing security against counterfeiting is the use of microprints. This security feature is used eg on bank notes. Such security features are also found in identity documents.

Packages made of plastic film, paper, cardboard or composites of these materials are usually provided with pull-tabs. The tape is secured to the package by a self-adhesive or thermal adhesive applied to the tape. US patents US4,887,714 and US4,844,962 are presently relevant.

EP0585076 describes the introduction of a security feature into a package in the form of an adhesive strip. In this case, holographic elements are used as security features. A disadvantage of holograms is that their special effects usually fail in low light. Moreover, making holograms is a complex, costly production process. Especially when producing the pull-away strips, the production process described has to be carried out in advance and cannot be integrated in the current production steps. The film supported for this purpose must be prepared and coated with an embossed varnish. The holographic pattern is then embossed. It must be metallized in the next step of the production process. Only then can it enter the traditional production process of pulling the belt. As such, the production process becomes more expensive and more complicated due to the multiple steps.

The task thus set forth was to provide a pull-away tape with safety features, the introduction of which does not entail new additional production steps in the production process of the pull-away tape.

The present invention therefore provides a pull-away tape with a security feature comprising a support film to which a sealing layer is applied on one side and optionally a release layer on the other side, characterized in that on one side of the support film Printed with miniature images.

The support film is preferably cellulose film, polyvinyl chloride, vinyl chloride copolymer, vinyl chloride terpolymer, polyester, polypropylene, polypropylene copolymer, polypropylene terpolymer, polypropylene/polyethylene copolymer, polypropylene amides, polystyrene, polystyrene copolymers, polystyrene terpolymers, polycarbonates, polyketones, polymethacrylates or polymethacrylate copolymers; especially preferably uniaxially oriented poly Propylene or polypropylene/polyethylene copolymer. In a particular embodiment, the support film may be a laminate of one or more polymer films with paper, metallized polymer films, metal foils, or vacuum-evaporated films.

The sealing layer is preferably a self-adhesive, pressure-sensitive adhesive based on polyacrylic or natural or synthetic resins.

An optional release layer is preferably a UV crosslinkable silicon coating.

The present invention also provides a production method for producing a pull-away tape with a security feature, wherein a support film is printed with a micrographic image, a sealing layer is applied to the image, and a release layer is optionally added to the support film. the other side.

According to the invention, the printed pull-away tape is produced such that in a single operation, a support film is printed and a sealing medium, such as a hot melt pressure sensitive adhesive, is added to the printing ink. A release coat is also optionally applied to the opposite side of the support film to prevent clogging. By employing suitable printing elements, security features can be introduced into the pull-away tape during this production process.

If printing is reverse printing, it is done so that, on the finished package, the printed information can be read through the packaging film, adhesive, and finally the support film.

The support film may have a thickness between 10-100 micrometers, and a width between 1-100 millimeters. The thickness is preferably between 10-40 microns, and the width is preferably between 1.5-10 mm, more preferably between 1-5 mm.

The sealing layer may comprise a sealing medium such as polyethylene or a so-called hot-melt coating, wherein the thickness of the layer is between 1 and 20 microns, and the sealing temperature is conventionally above 100°C.

Cold-settable, self-adhesive, pressure-sensitive adhesives based on polyacrylic acid or, in particular, on natural or synthetic resins are preferably used as sealing medium.

In the case of self-adhesive pressure-sensitive adhesives, the opposite side of the film is provided with a release coating. Preferably said coating comprises a layer of silicon, more preferably a layer of UV crosslinkable silicon.

The support film can be printed in a single color, or in multiple colors. Any printing process available for films can be used for this purpose. Printing can be done using the usual packaging printing processes, such as offset printing, screen printing, flexographic printing, UV flexographic printing or gravure printing; in particular offset printing or gravure printing, more especially gravure printing.

Miniature images include images having characters smaller than 0.7 mm, especially smaller than 0.3 mm; more preferably smaller than 0.26 mm. Printing can be arranged in the machine direction or cross-machine direction so that an observer of the packaged article can read the image with the aid of a magnifying device. Printing is preferably arranged in the machine direction, preferably with the centerline of the strip drawn.

Micrographics can be printed as a positive or reverse print. Orthographic printing is obtained by printing lines of letters or patterns. In contrast, reverse printing does not print the lines of the letter or pattern, but the area surrounding the letter or pattern.

Another embodiment has an image of normal size, ie, greater than 0.7 mm, which itself includes a miniature image. When the "normal" image is carefully examined with a magnifying glass or a microscope, the miniature image is discernible.

The pull-away strip according to the invention advantageously prevents counterfeiting of products. The said properties of inks which may be effective for this purpose may be implicit, ie discernable only by experts using technical methods, or explicit, ie non-experts can discern the authenticity of the product. In the first case, the purpose of the security element is to be able to provide critical proof of lack of authenticity in the case of counterfeiting. In the latter case, it is to enable consumers, sellers, or regulatory agencies, such as customs or the police, to use simple methods to identify the authenticity of the product.

Pull-away tapes of the described construction can be produced on conventional machines. The release layer is provided with successively dried or cured layers using a multi-roll applicator.

Printing on one side of the support film can be carried out using a known printing machine, one printing unit printing microscopic images.

The sealing medium is applied to the pattern using in-line or off-line gravure printing, or using a slot nozzle or other suitable method.

According to the invention, since the security element can be introduced during the printing process without additional production steps, it is possible to provide a pull-away strip with a security device in a particularly simple and economical manner.

The invention also provides a packaging material comprising a tear-off strip according to the invention, such as a film for packaging cigarettes, CDs or food.

The present invention is further described, but not limited, by the following examples in which all components and percentages are by weight unless otherwise indicated.

example 1

A monoaxially oriented polypropylene film having a thickness of 38 microns, wherein the maximum tensile force is greater than 160 Newtons, the elongation at break is greater than 25%, the tensile force at 10% elongation is greater than 32 Newtons, and the tear extension force is greater than 6 Newtons, in the machine direction The tensile rebound on the surface is greater than 1250 kJ/square meter, the tensile rebound in the transverse direction is greater than 100 kJ/square meter, the shrinkage rate (at 125°C and 10 minutes) is less than 6%, and the pretreatment amount is greater than 38 mm N/m, the film is coated with a mixture of silicon, which includes a solvent-free silicon acrylate with a polymerized photoinitiator, which is free-radically crosslinked by UV radiation in a protective gas environment, the mixing ratio of which is determined Loosening action of the cured silicon acrylate layer.

The next step involves gravure printing the opposite side onto the silicon-coated side, where the surface tension was previously adjusted to greater than 38 mN/m2 by corona treatment. A commercially available hot melt pressure sensitive adhesive based on SBS copolymer and condensation resin is added to the printing ink. The applied amount was 10 g/m2. In the next step, the film with this finish is cut to a width of 2 mm and a length of 6000 meters is wound on a reel.

Example 2

A cellulose film, 30 microns thick, printed by gravure, and hot-melt adhesive added to the ink, also printed by gravure, the composition of the adhesive comprising 25-45% ethyl/vinyl acetate Copolymer, 20-35% cyclohexanone hydrocarbon resin, 15-25% saturated hydrocarbon resin, 5-10% alpha methyl styrene hydrocarbon resin, and less than 10% oligomer polyurethane. The applied amount was 4 g/m2. In the next step, the film with this finish is cut to a width of 2 mm and a length of 6000 meters is wound on a reel.

Example 3

Same method as used in Example 1. However, the pressure sensitive adhesive used was a commercially available acrylate dispersion with a solids content of approximately 53% and a DIN 4 cup drain time of 60 seconds. The application rate was 3 g/m2; the aqueous dispersion was applied in gravure printing.

Although the foregoing description has been described in detail for the purpose of illustrating the present invention, it should be understood that such details are for the above purpose only, and without departing from the spirit and scope of the present invention, changes may be made therein for those skilled in the art, and only the appended claims describe them. limited.

Claims (13)

1. A multilayer draw back band, comprising: (i) supporting course of an orientation, it is a form of film, described film has microimage, comprises letter and zone; (ii) sealing layer, it bonds to the surface of described supporting course; And can select (iii) one to unclamp layer, it bonds to another surface of described supporting course.
2. Claim 1 draw back band, wherein microimage is just printed or anti-seal.
3. 3. claim 1 draws back band, wherein supporting course comprises one by the material of selecting in the group, and this group comprises cellulose, (being total to) poly-(vinyl chloride), polyester, (being total to) polypropylene, acid amides, (being total to) polyethylene, (being total to) polystyrene, polycarbonate, polyketone and (being total to) poly-(methyl) acrylate.
4. Claim 3 draw back band, wherein tread support membrane is a single shaft or biaxially oriented.
5. Claim 1 draw back band, wherein supporting course is a lamination, comprises at least one that selects from group, this group comprises thin polymer film, paper and metallic paper.
6. Claim 5 draw back band, wherein thin polymer film is metallized.
7. Claim 1 draw back band, wherein sealing layer is the self-adhesion lining cement.
8. Claim 1 draw back band, wherein sealing layer is a pressure sensitive adhesive.
9. Claim 1 draw back band, wherein unclamp layer and comprise a UV crosslinkable silicon coating.
10. Claim 1 draw back band, wherein microimage has character size less than 0.7 millimeter.
11. 11. produce the method that multilayer is drawn back band for one kind, be included in tread support membrane surface printing microimage, with the bonding surface that is applied to described tread support membrane of sealing layer, selectively unclamping layer with one is added on the another side of described tread support membrane, described supporting course is the form of orientation film, and described microimage comprises letter and zone.
12. 12. the method for claim 11, wherein microimage is applied by intaghlio printing.
13. 13. comprise the packing that draw back band of claim 1.