EP2182112B1

EP2182112B1 - Safety paper production method

Info

Publication number: EP2182112B1
Application number: EP08826363.7A
Authority: EP
Inventors: Arkadiy Vladimirovich Trachuk; Andrey Borisovich Kuryatnikov; Alexandr Georgievich Pisarev; Mikhail Anatolievich Ostrerov; Elena Samuilovna Turkina; Petr Alexandrovich Stryapushkin; Valeriy Anatolievich Vitvinin; Igor Mikhailovich Petrov; Sergey Ivanovich Chernyshov; Boris Petrovich Borisov; Stanislav Glebovich Ermakov; Oleg Stanislavovich Busyrev
Original assignee: Goznak FGUP
Current assignee: Goznak FGUP
Priority date: 2007-07-18
Filing date: 2008-07-16
Publication date: 2015-03-11
Anticipated expiration: 2028-07-16
Also published as: RU2344219C1; WO2009011616A3; WO2009011616A2; EP2182112A4; DE08826363T1; EP2182112A2

Description

Field of the invention

The invention relates to a method for producing safety paper which is used for producing fraud-proof printing product.

Background of the Invention

Methods for producing paper with a security strip-type element (in the form of thread or strip) are known and differ from each other only by combining that or other factors in molding process. The following factors may be classified as basic ones: a type of a product to be molded; a method for introducing a strip element (into pulp or onto a dry cylinder before it enters the pulp); the strip element itself (geometrical parameters, a material, presence or absence of local water permeability, etc.). Apart from being a security means, the strip element in the thickness of paper may serve to improve its physical and mechanical properties and - as a consequence and an aim - to increase its lifetime.
WO 2007/104855 A2 uses film segments fixed inside paper web. The film segments do not provide a possibility to vary shape and size of windows on each side of the security paper.
EP 1536064 A1 (or RU 2,207,417 C1 ) relates to a method for producing paper with a strip element introduced thereto. This method comprises the step of forming a paper web with a security strip having a width of more than 2 mm and being embedded into this web during the molding thereof on a wire-mesh cylinder. Simultaneously with the formation of the first paper web with the security strip a second paper web is formed, and both webs are connected in such a way that the second paper web is superposed to a side of the first paper web opposite to the wire side.
However this document does not disclose producing, during the step of forming the second paper web, continuous or periodical gaps having predetermined positions over the web. Thus, this solution does not provide obtaining through windows being zones for free accessing the strip simultaneously from two sides of the security paper.
WO 00/39391 A1 is the closest prior art to the present application and relates to a method for producing paper, said method comprising the step of forming a paper web with a security strip having a width of more than 2 mm and being embedded into this web during the molding thereof on a wire-mesh cylinder. The security strip is introduced into a pulp in such a way that, prior to contact thereof with the cylinder, a fibrous layer is molded, except for areas on a cylinder surface where the fibrous layer is not formed for lack of filtering property. Furthermore the security strip is positioned on the wire-mesh cylinder in such a way that a part of the surface thereof coincides with areas on a cylinder surface where the fibrous layer is not formed, and free access zones are formed as windows on a paper wire side. The security strip is partially exposed at a side opposite to a wire side. Therefore in some embodiments thereof this technical solution is directed to obtaining through windows. However it discloses a method of forming a single-layer paper web. Accordingly this reduces a possibility of forming through windows having different shape and design and obtaining a high protection level for a security paper and a printed matter.

Disclosure of the invention

It is an object of the present invention to provide a method for molding paper with introduction of a security element thereto as a result of which it is possible to create paper having the higher safety degree due to formation of "through windows" at a location where the security element lies.
The term "through windows" implies that a strip element introduced into the thickness of paper in a particular location of a paper sheet becomes accessible, exposed from the two sides of paper. A shape and length of said "through windows" may be arbitrary.
The problem posed is solved and the technical result is accomplished by a method for producing a safety paper, comprising the steps of: forming a paper web with a security strip having a width of more than 2 mm and being embedded into this web during the molding thereof on a first wire-mesh cylinder, wherein the security strip is introduced into a pulp in such a way that, prior to contact thereof with the cylinder, a fibrous layer is molded, except for areas on a cylinder surface where the layer is not formed for lack of filtering property; wherein said areas devoid of filtering property on the cylinder surface are created by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material or by making through holes in the wire mesh, wherein the security strip is positioned on the first wire-mesh cylinder in such a way that a part of the surface thereof coincides with areas on a cylinder surface where the fibrous layer is not formed, and free access zones are formed as windows on a paper wire side, wherein the security strip is completely or partially exposed at a side opposite to a wire side, thereby through windows are formed at locations where the windows on the wire side and the complete or partial outs of the security strip on the opposite side of paper coincide, wherein according to the method a second paper web is formed, simultaneously with the formation of the first paper web with the security strip, on a second wire-mesh cylinder, the second paper web being made with continuous or periodical gaps having predetermined positions over the web and predetermined shapes and sizes, and the second paper web being superposed to a side of the first paper web opposite to a wire side, wherein the paper webs are connected in such a way that the gaps in the second paper web are coincident with outs of the security strip of the first paper web and that said through windows are formed as zones for free accessing the strip simultaneously from two sides of the safety paper.
The method comprises the step of using the security strip having predetermined water permeability value over a surface area.
The method also comprises the step of using the security strip of a polymeric mesh or a non-woven material or a polymeric perforated film.
There is the step of introducing an additional security element - watermarks and/or security fibers and/or confetti - during the formation of the paper web.
Further, there is the step of using the security strip made with additional visual and/or computer-readable security elements.

Brief Description of the Drawings

The invention is explained by graphic materials.

Fig. 1 is a diagram that shows introduction of a security strip in operation with one molding cylinder (a first embodiment).
Fig. 2 shows paper with a security element having water-permeable edges.
Fig. 3 is a cross-section A-A of Fig. 2.
Fig. 4 is a cross-section B-B of Fig. 2.
Fig. 5 shows paper with a security element water-permeable throughout its surface.
Fig. 6 is a cross-section C-C of Fig. 5.
Fig. 7 is a cross-section D-D of Fig. 5.
Figs. 8, 9 show a cross-section E-E of Fig. 1 in different embodiments.
Fig. 10 is a diagram that shows introduction of a security strip in operation with two molding cylinders (a second embodiment).
Fig. 11 is a diagram that shows introduction of a security strip between two webs (a third embodiment).
Fig. 12 is a diagram that shows introduction of a security strip onto a ridge (a fourth embodiment).
Figs. 13, 14 show different embodiments of a cross-section F-F of Fig. 12.
Fig. 15 is a view A of Fig. 14 (an embodiment of the ridge).

The Best Mode of the invention

The method for producing a safety paper is carried out as follows.
According to the first embodiment (Fig. 1) of the method for producing a safety paper, the method includes forming a paper web 1 with a security strip (thread) 2 having a width of more than 2 mm and being embedded into the web 1 during the molding thereof on a wire-mesh cylinder 3. The security strip is introduced into a paper pulp 4 in such a way that, prior to contact thereof with the wire-mesh cylinder 3, a fibrous layer 5 is molded, except for areas on a surface of the cylinder 3 where the layer 5 is not formed for lack of filtering property. When the security strip is introduced, it is positioned on the cylinder 3 in such a way that a part of the surface thereof coincides with cylinder elements 6 where the layer is not formed, and free access zones are formed as windows on a paper wire side.
The elements 6 devoid of filtering property are made on the surface of the cylinder 3 by covering the wire mesh with a filigree or by pouring the wire mesh with a waterproof material, for example a polymer, or by making through holes in the wire mesh. In realization of the present embodiment of the method, the completely or partially exposed security strip is produced on a side opposite to a wire side, and through windows 7 are formed at locations where the windows on the wire side and the complete or partial outs of the security strip on the opposite side of paper coincide.
The security strip having predetermined water permeability value over a surface area is used in production of paper. The security strip can be made of a polymeric mesh or a non-woven material or a polymeric perforated film. A central portion of the strip can be made water-impermeable while side edges can be made water-permeable.
Fig. 2 shows the paper web 1 with the introduced security strip 2 made in the form of a water-permeable substrate 8 with a central water-impermeable portion 9 that can be made by depositing a polymer onto a mesh substrate, or the water impermeability of the central portion can be obtained by melting substrate fibers subjected to pressure and temperature in case of using a non-woven material. It is possible to provide the central portion with different shapes and sizes in order to obtain different shapes of the through windows 7.
Figs. 3 and 4 show cross-section A-A in a zone of a window and cross-section B-B between windows (according to Fig. 2), respectively.
Fig. 5 shows the paper web 1 with the introduced security strip 2 having the through windows 7 and being made as a water-permeable substrate 8 that is a lavsan film perforated throughout its width, a polymeric mesh or a non-woven material. The strip is free of paper fibers from two sides in a zone where the window 7 is formed (see Fig. 6 that is cross-section C-C of Fig. 5) and is covered by paper fiber layers on both sides in a zone between the windows 7 (see Fig. 7 that is cross-section D-D of Fig. 5).
Fig. 8 shows an embodiment of cross-section E-E of Fig. 1, where the element 6 is made as a water-impermeable element fastened on the surface of the wire-mesh cylinder 3 and preventing deposition of the paper pulp 4.
Fig. 9 shows an embodiment of the element 6 as a through hole 10 in the wire-mesh cylinder 3 with a filigree ending 11 designed to avoid deposition of fibers on uneven wire-mesh edges.
The holes 10 may be of arbitrary shapes and lengths. The difference between the holes is in that a hole is a zone where the pulp flow through the hole is unimpeded, without formation of a paper layer at this location, in the case with a water-impermeable element where a zone devoid of filtering property is created. "Through windows" are created in operation with a completely or partially water-impermeable element. For example, a strip element having water-impermeable edges and a water-impermeable central portion may be used. When such a strip element will contact the wire-mesh cylinder where holes are present and have a width being less than or the same as that of the water-impermeable portion of the strip element, deposition on a side opposite to the wire side will take place only where the surface has water permeability. At locations where holes were present, "through windows" are formed; if there was the case that the strip element had water permeability throughout its area, then the entire side opposite to the wire side would be covered by the paper layer at the location where the strip element lies.
An additional security element - watermarks and/or security fibers and/or confetti - is introduced during the formation of the paper web. This security element can comprise confetti and/or fibers of various shapes and chemical compositions within or on the surface of the paper web, including the confetti and/or fibers coated with or composed of materials with luminescent and/or magnetic properties and/or X-radiation absorbing materials, pigments with various optical effects such as pigments with an interference layer, liquid crystal pigments, and pigments with metallic effects.
The security strip is also produced with additional security elements, for example, on the basis of holographic images, including topographic images with hidden marks, that is, being observed using special devices as well as due to materials having magnetic and/or electro-conductive and/or luminescent properties, including materials having the luminescence when excited by ultraviolet, infrared and X-rays.
According to the second embodiment (Fig. 10) of the method for producing a safety paper, this method includes forming a paper web 1 with a security strip (thread) 2 having a width of more than 2 mm and being embedded into the web 1 during the molding thereof on a wire-mesh cylinder 3. The security strip is introduced into a paper pulp 4 in such a way that, prior to contact thereof with the wire-mesh cylinder 3, a fibrous layer 5 is molded, except for areas on a surface of the cylinder 3 where the layer 5 is not formed for lack of filtering property. When being introduced, the security strip 2 is positioned on the cylinder 3 in such a way that a part of the surface thereof coincides with cylinder elements 6 where the layer is not formed, and free access zones are formed as windows on a paper wire side.
The elements 6 devoid of filtering property are made on the surface of the cylinder 3 by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material, for example, a polymer, or by making through holes in the wire mesh (as in the first embodiment of the method). In realization of the present embodiment of the method, the completely or partially exposed security strip is produced on a side opposite to the wire side.
A second paper web 12 is formed on a wire-mesh cylinder 13 simultaneously with the formation of the first paper web 1 with the security strip 2, and said webs are connected in such a way that the second paper web 12 is superposed to a side of the first paper web 1 opposite to the wire side.
The second paper web 12 is made with continuous or periodical gaps 14 having predetermined positions over the web and predetermined shapes and sizes, wherein the paper webs are connected in such a way that the gaps 14 in the second web are coincident with outs of the security strip of the first web to form through windows being zones for free accessing the security strip simultaneously from two sides of paper.
Elements 15 devoid of filtering property are made on the surface of the cylinder 13 by covering the wire mesh with a filigree or by pouring the wire mesh with a waterproof material, for example a polymer, or by making through holes in the wire mesh.
The gaps 14 on the second paper web 12 can be also made after removal of this paper web from the wire-mesh cylinder 13 and prior to connection thereof to the first paper web 1. The gaps 14 can be made, for example, by local subjecting the paper web to an air of water jet.
The security strip having a predetermined water permeability value over a surface area is used during the production of paper. The security strip can be made of a polymeric mesh or a non-woven material or a polymeric perforated film. A central portion of the strip can be made water-impermeable while side edges can be made water-permeable (Figs. 2 to 7).
An additional security element - watermarks and/or security fibers and/or confetti - is introduced during the formation of the paper web. This security element may comprise confetti and/or fibers of various shapes and chemical compositions within or on the surface of the paper web, including the confetti and/or fibers coated with or composed of materials with luminescent and/or magnetic properties and/or X-radiation absorbing materials, pigments with various optical effects such as pigments with an interference layer, liquid crystal pigments, and pigments with metallic effects.
An additional security element, for example, on the basis of holographic images, including topographic images with hidden marks, that is, being observed using special devices as well as due to materials having magnetic and/or electro-conductive and/or luminescent properties, including materials having the luminescence when excited by ultraviolet, infrared and X-rays. According to the third embodiment (Fig. 11) of the method for producing a safety paper, this method comprises forming first and second paper webs 1 and 12 on wire- mesh cylinders 3 and 13. The first and second paper webs 1 and 12 are made with continuous or periodical gaps having predetermined positions over the web and predetermined shapes and sizes, wherein the security strip 2 of more than 2 mm in width is introduced between the webs 1 and 12 at a location of their connection in such a way that the security strip 2 coincides with an arrangement of gaps of both webs, and through windows are formed as zones for free accessing the security strip simultaneously from both sides of paper at locations where the gaps are coincident in the first and second webs. In order to make the gaps during the formation of the first paper web, areas devoid of filtering property are created on a cylinder surface by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material or by making through holes in the wire mesh.
In order to make the gaps in formation of the second paper web, areas devoid of filtering property are created on a cylinder surface by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material or by making through holes in the wire mesh.
In Fig. 11, the element 6 is made in the form of holes in the wire mesh of the cylinder 3 while the element 15 is made in the form of a filigree paper positioned over the entire circumference of the wire-mesh cylinder 13 in order to obtain a continuous gap over the surface of the paper web.
The security strip having a predetermined water permeability value over a surface area and being made, for example, of a polymeric mesh or a non-woven material or a polymeric perforated film is used.
An additional security element - watermarks and/or security fibers and/or confetti - is introduced during the formation of the paper web. This security element can comprise confetti and/or fibers of various shapes and chemical compositions within or on the surface of the paper web, including the confetti and/or fibers coated with or composed of materials with luminescent and/or magnetic properties and/or X-radiation absorbing materials, pigments with various optical effects such as pigments with an interference layer, liquid crystal pigments, and pigments with metallic effects.
The security strip is also produced with additional security elements, for example, on the basis of holographic images, including topographic images with hidden marks, that is, being observed using special devices as well as due to materials having magnetic and/or electro-conductive and/or luminescent properties, including materials having the luminescence when excited by ultraviolet, infrared and X-rays.
According to the fourth embodiment (Fig. 12) of the method for producing a safety paper, this method includes forming a first paper web with a security strip 2 having a width of more than 2 mm and being embedded into the web 1 during the molding thereof on a wire-mesh cylinder 3. Simultaneously with the step of forming the first paper web with the security strip 2, a second paper web 12 on a wire-mesh cylinder 13 is formed, and said webs are connected in such a way that the second paper web 12 is superposed to a side of the first paper web 1 opposite to the wire side. A ridge 16 is made on a surface of the wire-mesh cylinder 3 (see cross-section F-F of Fig. 12 in Fig. 13, and Fig. 14) by stamping the wire mesh, the security strip 2 is laid onto the ridge 16 prior to contact of the wire mesh with a paper pulp, and free access zones are formed at a location where the security strip 2 contact the ridge 16. The ridge 16 is made with figured edges 17 of a predetermined shape (Fig. 15). An opposite side of the security strip is left exposed, wherein the second paper web is made with continuous or periodical gaps having predetermined positions over the web and predetermined shapes and sizes. The paper webs are connected in such a way that the gaps in the second web are coincident with outs of the security strip of the first web to form through windows being zones for free accessing the security strip simultaneously from two sides of paper.
In order to make the gaps in formation of the first paper web, areas devoid of filtering property are created on a cylinder surface by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material or by making through holes in the wire mesh.
The gaps on the second paper web are made after removal of this paper web from the molding cylinder and prior to connection thereof to the first paper web.
The security strip having predetermined water permeability value over a surface area, for example, the security strip of a polymeric mesh or a non-woven material or a polymeric perforated film is used.
An additional security element - watermarks and/or security fibers and/or confetti - is introduced during the formation of the paper web.
The security strip made with additional visual and/or computer-readable security elements is used.

Industrial Applicability

The inventive methods for producing a safety paper allow production of paper with a strip-type security element having through windows. Use of such a paper in the production of fraud-proof printing goods provides the reliable protection of valuable papers against falsification because the through windows represent an element hard to be falsified; further, by using additional security features, including that on the strip element, it is possible to obtain diverse visual and computer-readable security features. The inventive methods are practically feasible, and their diversity allows selection of an embodiment of the method for producing a safety paper optimal for each particular production.

Claims

A method for producing a safety paper, comprising the steps of:
forming a first paper web (1) with a security strip (2) having a width of more than 2 mm and being embedded into this web (1) during the molding thereof on a first wire-mesh cylinder (3), wherein the security strip (2) is introduced into a pulp (4) in such a way that, prior to contact thereof with the cylinder (3), a fibrous layer (5) is molded, except for areas (6) on a cylinder surface where the fibrous layer (5) is not formed for lack of filtering property, wherein said areas (6) devoid of filtering property on the cylinder surface are created by covering the wire mesh with a filigree paper or by pouring the wire mesh with a waterproof material or by making through holes in the wire mesh,

wherein the security strip (2) is positioned on the first wire-mesh cylinder (3) in such a way that a part of the surface thereof coincides with areas (6) on a cylinder surface where the fibrous layer (5) is not formed, and free access zones are formed as windows on a paper wire side, wherein the security strip (2) is completely or partially exposed at a side opposite to a wire side, thereby through windows are formed at locations where the windows on the wire side and the complete or partial outs of the security strip on the opposite side of paper coincide,

the method being characterized in that

a second paper (12) web simultaneously with the formation of the first paper web (1) with the security strip (2) is formed on a second wire-mesh cylinder (13), the second paper web (12) being made with continuous or periodical gaps having predetermined positions over the web (12) and predetermined shapes and sizes, and the second paper web (12) being superposed to a side of the first paper web (1) opposite to the wire side, wherein the paper webs (1, 12) are connected in such a way that the gaps (14) in the second paper web (12) are coincident with outs of the security strip (2) of the first paper web (1) and that said through windows are formed as zones for free accessing the strip simultaneously from two sides of the safety paper.
The method according to claim 1, characterized by the security strip (2) having predetermined water permeability value over a surface area.
The method according to claim 2, characterized by the security strip (2) of a polymeric mesh or a non-woven material or a polymeric perforated film.
The method according to claim 1, characterized by introducing an additional security element - watermarks and/or security fibers and/or confetti - during the formation of the paper webs (1, 12).
The method according to claim 1, characterized by the security strip (2) made with additional visual and/or computer-readable security elements.