WO2015112105A1

WO2015112105A1 - Method for producing a perforated integral stack of polycarbonate sheets

Info

Publication number: WO2015112105A1
Application number: PCT/UA2014/000053
Authority: WO
Inventors: Георгий Владимирович БЕЙЛИН; Владимир Леонидович ВОЗНЫЙ; Юрий Григорьевич СИДОРЕНКО; Андрей Николаевич ТИМОШЕНКО; Игорь Николаевич ПОПОВИЧ; Георгий Борисович СИДОРОВ
Original assignee: Общество С Ограниченной Ответственностью "Специализированное Предприятие "Голография""; Георгий Владимирович БЕЙЛИН; Владимир Леонидович ВОЗНЫЙ; Юрий Григорьевич СИДОРЕНКО; Андрей Николаевич ТИМОШЕНКО; Игорь Николаевич ПОПОВИЧ
Priority date: 2014-01-21
Filing date: 2014-05-30
Publication date: 2015-07-30

Abstract

The proposed invention relates to a method for creating forgery-protected integral stacks of polycarbonate sheets in order to produce various valuable documents, by means of applying perforated images thereto with the goal of complicating the possibility of counterfeiting the given product and decreasing the number of defective integral stacks of polycarbonate sheets. The method includes forming a stack from individual polycarbonate sheets having a thickness of 50-100 micrometers, connecting same in order to form an integral stack, and perforating a certain area of the integral stack by means of laser radiation. Positioning a stack between two rigid parallel plates, heating the formed stack in stages, from room temperature to the temperature at which polycarbonate becomes soft, holding the stack, during each stage, at predetermined temperatures and compressing for 10-15 seconds in order to level and stabilize the temperature gradient on the entire plane of the field of the stack, and simultaneously, at each subsequent stage, increasing the value of the compression acting upon the assembled stack. Holding the stack, during the final stage, in a compressed state, until an integral stack having a thickness of 500-1000 micrometers is formed, cooling the formed integral stack together with the plates until room temperature is reached, freeing the stack from the plates and positioning the stack vertically between two parallel frames, and perforating a certain area of the integral stack comprised of individual polycarbonate sheets by means of laser radiation in a working field delimited by the frames.

Description

A method of manufacturing a perforated monolithic package

from polycarbonate sheets.

The present invention relates to means for creating fake-protected monolithic bags made of polycarbonate sheets for the manufacture of various securities and documents, such as, for example, identification cards, passes, etc., by applying perforated images and / or symbolic information to them, in order to significantly complicate the possibility of falsification or unauthorized reproduction of the mentioned products.

Closest to what is proposed by technical nature by the number of significant ones. of features is a method for manufacturing a perforated monolithic bag from polycarbonate sheets, comprising forming a bag of individual polycarbonate sheets, combining them to form a monolithic bag and perforating a specific portion of the monolithic bag with laser radiation [International application PCT7NL2010 / 050884 from 12/23/2010; international publication WO 201 1/078674 A1 of 06/30/2011 1]. According to the aforementioned method, a package of polycarbonate sheets is preliminarily laminated and a lining is obtained, which is perforated by laser radiation with a wavelength of 9.30 micrometers.

Lamination or lamination is the process of applying a transparent film-laminate to printed products. Among the known, the most common is a film based on polyester. Such a multilayer film includes a base layer of polyester, which gives rigidity to the film, a layer of polyethylene that acts as a binder, and a layer of polymer “glue” (EVA - ethylene vinyl acetate) - a low-melting (95-120 ° C) polymer with adhesive properties [information from the site http://ru.wikipedia.org/wiki/%D0%9B%D0%B0%D0%BC%D0%B8%D0%BD%D0%B8%D 1% 80% D0% BE% D0% B2% D0% B0% D0% BD% D0% B8% D0% B5_% D0% BF% D0% BE% D 0% BB% D0% B8% D0% B3% D1% 80% D0% B0% D 1% 84% D0% B8% D 1% 87% D0% B5% D 1% 81% D0% BA% D0% BE% D0% B9_% D0% BF% D 1% 80% D0% BE% D0% B4% D 1% 83% D0% BA% D 1% 86% D0% B8% D0 % B8].

In the process of laminating a sheet of polycarbonate, the properties of the resulting package, in particular the optical ones, change. Such changes in many cases are unpredictable and irreversible due to the presence of an adhesive layer, the physical properties of which differ from the physical properties of polycarbonate. The unpredictability of changes in properties, mainly properties of the adhesive layer, leads to rejection of part of the manufactured sheets already at the stage of checking the finished product and subsequent rejection of another part of the product at the stage of use due to aging of the adhesive layer under the influence of external factors (e.g., light) and. as a result, the occurrence of defects in it that distort the image, which limits the application of this method for the manufacture of securities and / or documents,

In addition, the process of applying personalized information by laser engraving onto a polycarbonate layer, which in such a structure inevitably is positioned behind the lamination film (layer) and the adhesive layer, is also problematic due to the absorption of laser radiation by the layers located above. Such absorption leads to carbonization (carbonization) and, as a result, to undesirable blackening and (or) destruction of areas in the areas of interaction of laser radiation with the lamination film (layer) and the adhesive layer.

The basis of the invention is the task of creating such a method of manufacturing a perforated monolithic bag from polycarbonate sheets, which would reduce the number of rejected monolithic bags from polycarbonate sheets by eliminating the film and / or adhesive layer from the process of use and, thus, would reduce the likelihood of occurrence carbonization of sheets in areas of its perforation by laser radiation. The problem is solved by creating conditions for the gradual softening of polycarbonate sheets and their stepwise compression until a monolithic package is created from individual leaves, as well as the use of laser radiation with an optimal wavelength during perforation.

The proposed, as well as the known method of manufacturing a perforated monolithic package of polycarbonate sheets, includes forming a package of individual polycarbonate sheets, combining them to form a monolithic package and perforating a specific portion of the monolithic package with laser radiation, and, in accordance with the invention, formed from individual polycarbonate sheets A J packet with a thickness of 50-100 micrometers is placed between two rigid parallel plates, the formed bag is heated stepwise from room temperature to the softening temperature of the polycarbonate, it is held at each stage at the temperature and compression values determined for it for 10-15 seconds to equalize and stabilize the temperature gradient on the entire plane the field of the package and at the same time, at each next stage, increase the compression value on the assembled package, keep it at the last stage in a compressed state until it forms a monolithic bag with a thickness of 500-1000 micrometers, cool the formed monolithic bag together with the plates to room temperature, free the bag from the plates and place it vertically between two parallel frames, and perforation of a certain section of the monolithic package from individual polycarbonate sheets is performed by laser radiation in a working field limited the framework.

Polycarbonates belong to the group of thermoplastics - polymeric materials that can reversibly pass upon heating to a highly elastic or viscous state, and upon transition to the solid state retain the properties that they had before heating. This feature of polycarbonates made it possible to create conditions for the production of individual polycarbonate sheets, each (or some) of which contain certain graphic information, a monolithic package of individual sheets by pressing them at a softening temperature of the sheet material (about +150 ° C). The resulting package of individual sheets has a rigidity sufficient for its further processing and application of perforation.

The authors experimentally established the optimal value of the wavelength of laser radiation to perform the technological operation of punching the package. So, for example, when using a powerful gas laser with a radiation wavelength of 10.6 micrometers to perforate the radiation, the material was exposed. gouting and acquired a brown coating at the perforation sites. Laser radiation with a wavelength of 9.35 micrometers turned out to be optimal for perforating a packet of individual polycarbonate sheets with a thickness of 500-100 micrometers.

The schematic drawings show the proposed manufacturing process of a perforated monolithic package of individual sheets of polycarbonate.

Figure 1 shows the operation of assembling the package and placing it between the plates.

Figure 2 shows the process of creating a monolithic package. On Fig. 3 shows the processes of laser perforation of a monolithic package of individual sheets of polycarbonate and laser processing of the surface of one of the inner layers of the package from the front side.

In the schematic drawings, reference numeral 1 denotes a pre-assembled bag of individual polycarbonate sheets. Position 2 - rigid plates designed to accommodate the assembled package between them 1. The monolithic package formed after heating is indicated by position 3. Parallel frames designed to hold the monolithic package 3 during its perforation are indicated by 4. Radiation of a gas laser designed for perforation package 3, indicated by the position 5. Radiation of a solid-state or fiber laser, intended for processing by laser radiation the surface of one of the inner layers of the package and the front side, indicated by reference numeral 6. Land with replaceable reflectance indicated by reference numeral 7.

Example. Previously, package 1 was assembled from individual sheets of polycarbonate sheet with a thickness of 50-100 micrometers. Some sheets had certain protective elements, including holographic ones, applied by known methods, for example, by the method described in the Ukrainian patent for utility model M> 15842, IPC (2006) B42D 15/10 (2006.01), G06K 19Ό0; published July 17, 2006, bull. N ° 7/2006. The assembled bag 1 was placed between two rigid parallel plates 2, which were stepwise heated by contacting with the heated liquid to the softening temperature of the polycarbonate — approximately 148–152 ° С, and at the same time, the compression value of the assembled packet 1 was increased at each stage. (at the temperature and compression values determined for it) 10 - 15 seconds to equalize and stabilize the temperature gradient along the entire plane field of packet 1. The process was stopped after the formation of a monolithic packet 3 a certain thickness (500 - 1000 micrometers). Thanks to the use of stepwise heating and compression processes, a monolithic package 3 was obtained without the use of a lamination operation, as well as exclusions from the film and glue process. Formed monolithic package 3 was cooled in calm air along with plates 2 to room temperature. The package 3 was released from the plates 2 and placed vertically between two parallel frames 4. Perforated monolithic package 3 laser radiation with a wavelength of 9.35 micrometers in the working field, limited by frames 4.

To carry out punching, the M-601 - “System for graphic and electronic personalization of ID3-format documents” machine manufactured by EDAPS-Laser Limited Liability Company (Kiev) was used. The specified machine consists of seven modules: loading, opening a document, electronic coding of a contactless microchip, applying graphical information using laser engraving, applying a DLI security element, applying symbolic information using laser perforation, quality control, document closing and unloading module / drawings not shown. Each of these modules is designed to perform a specific technological operation.

In a given section of the monolithic packet 3, a perforated image 2 was formed using a laser beam 5 of a gas laser with a radiation wavelength of 9.35 micrometers. Then, using the same machine, a solid-state or fiber laser was used on the front side of packet 3 with a laser beam 6 with a radiation wavelength 1, 06 micrometers, sections with a shift reflectance of 7 were formed and an image was obtained from a combination of two images: images in the form of an array of holes of different diameters observed in transmitted light, and from Brazings in the form of an array of points with a variable reflection coefficient observed in reflected light.

The quality of each obtained monolithic packet 3 with a laser perforation section was checked for its compliance with the established requirements in relation to optical qualities. The number of rejected products manufactured in accordance with the described method was 10 to 15 times less than the number of rejected products made by the prototype method. Thus, the proposed method of manufacturing a perforated monolithic package of polycarbonate sheets allowed to significantly reduce the number of defective products by creating conditions for exclusion from the process of using the film and the adhesive layer.

Claims

Claim.

A method of manufacturing a perforated monolithic bag of polycarbonate sheets, comprising forming a bag of individual polycarbonate sheets, combining them to form a monolithic bag and perforating a specific portion of the monolithic bag with laser radiation, characterized in that the bag formed from individual polycarbonate sheets with a thickness of 50-100 micrometers is placed between two rigid parallel plates, stepwise heat the formed package from room temperature to the softening temperature of polycarbonate, they are held at each stage at the temperature and compression values determined for it for 10-15 seconds to equalize and stabilize the temperature gradient on the entire plane of the packet field and at the same time, at each next stage, increase the compression value on the assembled packet, keep the packet at the last stage in a compressed state until a monolithic bag is formed with a thickness of 500-1000 micrometers, cool the formed monolithic bag together with the plates to room temperature, free the bag from the plates and place it vertically Between two parallel frames, and the perforation of a certain section of the monolithic package of individual sheets of polycarbonate is performed by laser radiation in the working field bounded by the frames.