CN1100081C - Antiforge pressure-sensitive marker of high-molecular porous compound film and its preparing process - Google Patents

Abstract

The invention relates to an anti-counterfeiting mark of a pressure-sensitive polymer porous composite film and a preparation method thereof. The existing anti-counterfeiting marks are either pasted with simple graphics and texts, or rely on temperature changes to display graphics and texts, which are easy to counterfeit and cannot be directly observed. The anti-counterfeiting mark compounded by the polymer porous film and microcapsules in the present invention is bonded with pictures and texts under the composite film. Generally, no pictures and texts are displayed, and when the finger-pressed microcapsules are broken and the solvent in the capsule is filled with the small holes in the film, that is, Display inner text. The anti-counterfeiting mark is convenient to make, has good anti-counterfeiting effect and has wide application prospects.

Description

Pressure-sensitive polymer porous composite film anti-counterfeiting label and preparation method thereof

The invention relates to an anti-counterfeit mark compounded by a polymer porous film and a microcapsule and a preparation method thereof.

Polymer porous membranes have very important applications in the fields of bioengineering, drug synthesis, chemical engineering, and high-tech anti-counterfeiting marks. The commercialized polymer porous membrane has a certain pore size range and specific structure and function. For example, the "Celgard" porous film produced by the American Celanese company, the polystyrene porous film produced by the American Akozo company, etc., the diameter of the pores is in the range of 0.4 μm to 1.5 μm. It is about μm, so it cannot meet the needs of users with different requirements. US patents 4,846,095, 4,374,889, 4,733,786, 5,389,426 respectively introduced the method of preparing a polymer porous membrane that can be used for anti-counterfeiting labels by means of "thermally induced phase separation". It is known that such a polymer porous film exhibits opaque properties in an air medium because the refractive index of the porous film is inconsistent with that of the air medium. When a certain solvent with the same refractive index as the porous membrane is selected to fill the porous membrane, the porous membrane will become transparent. According to this principle, a special anti-counterfeiting mark sensitive to a special solvent can be designed. For example, the "critical temperature display system" mentioned in U.S. Patent 4846095 has designed a mark based on a porous film. When the mark is soaked by a mixed medium, the inner layer graphics cannot be observed from the mark surface; at the critical temperature, the mixed The phase separation of the medium makes the porous film on the surface of the logo transparent, so that the inner layer of graphics can be observed. U.S. Patents 4,374,889 and 4,733,786 are also based on the invention that the logo text changes under temperature changes, but the change in refractive index caused by temperature changes is due to the change in the structure of the porous membrane itself after being heated. Another example is the "anti-tampering and fidelity mark" mentioned in US Patent No. 5389426. The change of the refractive index of the porous film is based on the change of the volatility of the filling solvent used.

The inventions of the above-mentioned anti-counterfeiting marks of porous membranes are all based on the different changes of the graphics and texts caused by temperature changes. At present, there are no reports of anti-counterfeiting marks with a more direct and simple method.

The purpose of the present invention is to research a kind of mark that can directly observe the anti-counterfeiting graphic and text with a little external force and its preparation method.

The mark of the present invention is mainly made of a polymer porous film and a pressure-sensitive microcapsule, and a pressure-sensitive microcapsule layer is compounded under the polymer porous film, and a solvent is wrapped in the microcapsule, and the refractive index of the solvent is the same as that of the film. The thickness of the porous film layer is 50-200 μm, the pore diameter is 0.1-10 μm, and the thickness of the microcapsule layer is 10-50 μm. The microcapsule porous composite membrane is then compounded on the surface of the printed graphic. Before external force is applied, the logo can display the graphic printed on the surface of the porous membrane, but the graphic (code) printed on the inner layer of the composite membrane is invisible. . The adopted microcapsule shell material can be formed by thermal curing of natural polymer or emulsion polymerization of polymer monomer, and its core material is a solvent whose refractive index is the same as that of the porous film. Under the action of external force, the solvent produced by the rupture of the microcapsules will fill the porous membrane, thus making the membrane transparent and displaying the inner layer of graphics (code).

The porosity of the porous film of the anti-counterfeiting mark of the composite film is 50-85%, and an appropriate amount of holes increases the transparency when the solvent in the microcapsules fills the holes.

After research and exploration, it is found that the proportion of microcapsules in the porous membrane is better in the range of 10% to 50%, too much is unnecessary, and too little reduces transparency.

The preparation of the porous film in the present invention is to be drawn into a film by thermoplastic polymer material and solvent according to (30～80)%: (20～70)% ratio, and drawing method adopts " heat-induced phase separation " method, is the current production method. Existing technology in the film: then do the core material in the microcapsule with the solvent identical with macromolecular porous film refractive index, make the shell material of microcapsule with natural macromolecular material or synthetic macromolecular material, prepare microcapsule with existing The microcapsule emulsion is synthesized by technology, and the microcapsule layer and the porous film layer are bonded and compounded after bonding the graphic layer on the backing paper.

Polyethylene and polypropylene can be used as polymer film materials in the above preparation process: gelatin, gum arabic, polystyrene, polyester, etc. are the shells of the microcapsules, and trichlorethylene, water, unsaturated fatty acids, oleic acid, etc. are the core materials of the microcapsules.

If there is also an anti-counterfeiting mark with a graphic mark on the surface of the preparation, the graphic layer can be bonded on the self-adhesive and isolation backing paper, and then the composite layer of microcapsules and porous film can be bonded on the upper layer, and the surface graphic layer can be bonded on the composite layer. , in order to protect the surface graphic layer from abrasion, a layer of transparent polymer film protective layer is covered on the surface graphic layer. In this way, what can be seen when the composite film is not subjected to external finger pressure is the surface graphic layer, and when the finger pressure capsule is broken and the solvent fills the holes in the film, the inner layer graphic layer can be seen. Examples describe this in detail.

In the present invention, the porous film and the microcapsule are bonded together with a pressure-sensitive adhesive, which is simple, convenient and effective.

Compared with the existing anti-counterfeiting marks, the anti-counterfeiting mark of the invention is convenient to use and has good anti-counterfeiting effect. The simplest anti-counterfeiting label in the prior art is the bonding of single-layer graphics and texts, and the more complicated ones depend on temperature changes. The product of the present invention can display the inner layer of graphics and texts with just a light press of a finger, and can directly distinguish the true from the false, giving The use of anti-counterfeiting marks brings great convenience.

The invention has low cost, easy to obtain raw materials, simple preparation, easy popularization and very good application prospect.

Example 1.

Preparation of porous film: 60% polyethylene and 40% mineral oil are heated and melted at 200°C, and the film is drawn on a temperature-controlled film drawing machine while maintaining the molten state. The adjustment of film thickness is completed at 50°C, and the thickness of the obtained film is controlled. is 90 μm. After polyethylene and mineral oil are phase-separated, the membrane is passed through a tank containing petroleum ether as an extractant, and the mineral oil contained in the membrane is separated. The obtained polyethylene porous membrane had a pore diameter of about 0.4 μm.

Preparation of microcapsules:

10 parts of gelatin, 5 parts of gum arabic and 85 parts of water are heated and dissolved to obtain component a;

70 parts of a, 25 parts of trichlorethylene, and 5 parts of 4% ethylene maleic anhydride copolymer (trade name: EMA-31MONSANTO CHEMICAL CO) were emulsified at 80°C for 30 minutes under high-speed stirring. After cooling, emulsion b containing microcapsules was obtained.

Production of anti-counterfeiting label: The label is composed of 7 layers of units. Layer 7 (the innermost layer) is an adhesive layer, about 5 μm thick, which is made of ordinary self-adhesive coating and isolation backing paper; layer 6 is an ordinary trademark unit, which can be silk screen or printed on coated paper or PET film as the base material Offset printing products, such as the red Tesson logo made by silk screen printing; layer 5 is the coating layer of the above component b, with a thickness of 20 μm; layer 4 is the adhesive layer, which is coated with 3M pressure-sensitive adhesive Acrylic 100 for 5 μm; layer 3 is the above-mentioned polyethylene porous film layer, the surface of the composite and adhesive layer; the surface text layer of layer 2 is printed on the surface of layer 3 by silk screen printing or offset printing, such as the four words "TESON Anti-counterfeiting" in light blue On it; Layer 1 is a surface protection layer, which is a PVC coating layer with a thickness of 2 μm.

The complete anti-counterfeiting mark made according to the above process is observed from the surface, and only the four characters of "Teschen Anti-counterfeiting" can be seen in light blue. On the background of the four characters "Tieshen Anti-counterfeiting" in blue.

Example 2.

Preparation of porous film: 70% polypropylene and 30% mineral oil are heated and melted at 200°C, and the film is drawn on a temperature-controlled film drawing machine while maintaining the molten state. The adjustment of film thickness is completed at 50°C, and the thickness of the obtained film is controlled. is 10 μm. After polyethylene and mineral oil are phase-separated, the membrane is passed through a tank containing petroleum ether as an extractant, and the mineral oil contained in the membrane is separated. The obtained polyethylene porous membrane had a pore diameter of about 1.2 μm.

Preparation of microcapsules:

15 parts of gelatin, 8 parts of gum arabic and 77 parts of water are heated and dissolved to obtain component a;

70 parts of a, 25 parts of trichlorethylene, and 5 parts of 4% ethylene maleic anhydride copolymer (trade name: EMA-31MONSANTO CHEMICAL CO) were emulsified at 80°C and 5000 rpm for 30 minutes while stirring. After cooling, emulsion b containing microcapsules was obtained.

Production of anti-counterfeiting label: The label is composed of 7 layers of units. Layer 7 (the innermost layer) is an adhesive layer, about 5 μm thick, which is made of ordinary self-adhesive coating and isolation backing paper; layer 6 is an ordinary trademark unit, which can be silk screen or printed on coated paper or PET film as the base material Offset printing products, such as the red Fudan logo made by silk screen printing; layer 5 is the coating layer of the above component b, with a thickness of 20 μm; layer 4 is the adhesive layer, which is coated with 3M pressure-sensitive adhesive Acrylic 100 for 5 μm; layer 3 It is the surface of the above-mentioned polypropylene porous film layer, composite and bonding layer; the surface layer of layer 2 is printed on the surface of layer 3 with silk screen printing or offset printing, such as the four words "Fudan University" in light green; Layer 1 is the surface protection layer, which is a PVC coating layer with a thickness of 2 μm.

The complete anti-counterfeiting mark made according to the above process is observed from the surface, and only the four characters of "Fudan University" in light green can be seen. Fudan University" on the background of the four characters.

Claims (6)

1. An anti-counterfeiting mark of a pressure-sensitive polymer porous film, which is mainly composed of a polymer porous film and a pressure-sensitive microcapsule, and is characterized in that a pressure-sensitive microcapsule layer is compounded under the polymer porous film, and there is a printed film under the composite layer. The anti-counterfeiting graphic layer made of the composite porous film layer is 50-200 μm thick, the pore size is 0.1-10 μm, the microcapsule layer thickness is 10-50 μm, and the refractive index of the solvent in the microcapsule is the same as that of the polymer porous film. 2. The anti-counterfeit mark of the pressure-sensitive polymer porous composite film according to claim 1, characterized in that the porosity of the porous film is 50-85%. 3. The anti-counterfeiting mark of the pressure-sensitive polymer porous composite film according to claim 1, characterized in that the proportion of microcapsules in the porous film is 10-50%. 4. the preparation method of pressure-sensitive macromolecule porous composite film anti-counterfeiting mark according to claim 1 is characterized in that prepare porous film, microcapsule earlier, compound then; With thermoplastic polymer material and solvent press (30～80 )%: (20-70)% ratio to draw into a film; use the same solvent and polymer material as the polymer film to make an emulsion containing microcapsules, and then bond the graphic layer on the backing paper, and the microcapsules The capsule and the porous film layer are bonded to form a composite layer. 5. the preparation method of pressure-sensitive macromolecule porous composite film anti-counterfeit label according to claim 4 is characterized in that when composite film anti-counterfeit label is made, bonding graphic layer on self-adhesive and isolation backing paper, its upper layer is a microcapsule A composite layer with a porous film, on the composite layer is a surface graphic layer, and a transparent polymer film protective layer is formed on the surface graphic layer. 6. The preparation method of the anti-counterfeiting mark of the pressure-sensitive polymer porous composite film according to claim 4, characterized in that the porous film and the microcapsules are composited with a pressure-sensitive adhesive.