FI118351B - Fibrous web processing device for processing fibrous web, e.g. board, has processing zone length defined by disposition/adjustment of belt's guiding roll and/or counter-roll design, and has specified contact pressure - Google Patents

Abstract

Fibrous web processing device comprises belt (2), guiding roll(s) (3), and counter-roll(s) (5). The belt extends around the guiding roll(s). The belt and the counter-roll(s) establish a web processing zone between them. The processing zone is defined by disposition/adjustment of the belt's guiding roll and/or by the design of the counter-rolls. A contact pressure applied to the web in the processing zone is 0.01-200 MPa. Fibrous web processing device comprises belt, guiding roll(s), and counter-roll(s). The belt extends around the guiding roll(s). The counter-roll(s) is disposed outside the belt to provide a contact area with the belt. The belt and the counter-roll(s) establish a web processing zone between them. The web processing zone allows a web to be processed to pass through it. The processing zone is defined by disposition/adjustment of the belt's guiding roll and/or by the design of the counter-rolls. A contact pressure applied to the web in the processing zone is 0.01-200 MPa. Independent claims are included for: (1) making release paper, (coated) board product, safety paper, and newsprint comprising passing a paper web from press section of a paper machine through calendering process(es) using the inventive device; (2) making mechanical pulp containing coated paper and (un)coated chemical-pulp base fine paper comprising passing the paper web from the press section of paper machine through pre-calendering process(es) upstream of a coating stating and/or through the final calendering process(es) downstream of the coating station using the inventive device; and (3) a calender for making safety paper from a fibrous web comprising calendering surface(s) with impressions complementary to areas intended for surface of fibrous web and with shape designs.

Description

1,118,351

Security paper and equipment and method for making security paper

The present invention relates to security paper and apparatus and a method for making security paper. In this context, security paper refers to 5 paper or paperboard which can be used, for example, as a printing surface or packaging material, and is characterized in that it is difficult to produce without proper equipment, i.e. it is difficult to forge.

Traditionally, security paper has used different colored or fluorescent fibers, ho-lograms, watermarks, etc., to indicate the authenticity and origin of the paper or packaging made of, for example, cardboard. However, such solutions are expensive and are mainly applicable to banknote papers or other products with a high value-to-manufacturing ratio.

WO / 0198588 and US-6402888 disclose methods in which paper is identified by forming areas on the paper that are different from its surroundings, i.e., patterns or text, for example. More specifically, smaller thicknesses are formed on the paper that are clearly distinguishable from the rest of the paper surface when compared to other areas of the fibrous web. However, these processes are only applicable to certain types of multi-ply paper or board. In addition, the security paper manufacturing process according to the first publication requires a number of different steps to produce the final product, including post-treatment (plating) after forming the paper identifying patterns. The security paper according to the latter publication, in turn, is formed of two fiber webs formed in two separate wet ends of the paper machine by gluing them together and drying them. Thus, such methods are complex and obfuscate.

US-6174586 also discloses a known method for producing security paper. Therein, the patterns or text identifying the paper are formed solely by embossing or embossing on the coating applied to the paper surface. Also, such a method is only suitable for certain types of paper, especially only for paper grades. In addition, the method is slow so it is difficult to apply it online as a paper machine.

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It is an object of the present invention to provide security-labeled paper or paperboard which is simple, fast and inexpensive to manufacture, and a method and apparatus for making such paper or board, and even so that the method and apparatus are well suited to both uncoated 10 and coated paper and board grades. .

The problem is solved by making identified security paper by calendering the fibrous web with a calendar, preferably a metal belt calender, wherein at least one calendering surface is engraved with identifying paper-like recesses, such as a company logo or text, without calendering, which non-calendering areas are clearly distinguishable from the rest of the calendered surface of the fibrous web, and that said at least one calendering step for producing security paper 20 and forming desired pattern-shaped areas on the fibrous web Γ ·] occurs at the last calendering step of a paper or board machine.

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The particular purpose of the method and equipment for making a security paper for the task is to apply to a wide variety of coated and uncoated paper and board. There are many different types of paper and board that can be divided into • t · 1 · 2 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · As you can see, the border between paper and cardboard is slippery, as the lightest cartons are lightweight • 9 · 9 9 9 9 9 9 9 9 9 9 9 3 118351 Paper is generally used for printing and cardboard for packaging.

The following descriptions are examples of the current value of non-cash borrowings and may be subject to significant fluctuations in the given values.

Mechanical pulp or wood-containing printing papers are newsprint, uncoated magazine paper and coated magazine paper.

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The newsprint (either Newsprint) can either consist entirely of mechanical pulp or may contain low levels of bleached softwood pulp (0-15%) and / or recycled fiber can be used to replace mechanical pulp. General values for newsprint should be as follows: basis weight 40-50 g / m2, ash content 15 0-20%, PPS S10 roughness 3.0-4.5 pm, Bendtsen roughness 100-200 ml / min, density 600-750 kg / m3, lightness 57-63% and opacity 90-96%.

Uncoated magazine paper (SC = supercalendered) generally has a mechanical pulp of 50-70%, bleached softwood pulp 10-25% 20 and fillers 15-30%. Typical values for calendered SC paper (including, inter alia, SC-C, SC-B and SC-A / A +) are 40-60 g / m 2 basis weight, ash content 0-35%, Hunter gloss 20 - 50%, PPS S10 roughness 1.0 - 2.5 µm, density 700 - 1250 kg / m3, brightness 62 - 70% and opacity 90 - 95%.

Lightweight Coated Magazine Paper (LWC) contains 40-60% mechanical pulp, 25-40% bleached softwood pulp, and refill and overlay. improvers 20-35%. The general values for LWC paper are: • ··] ···. basis weight 40-70 g / m2, Hunter gloss 50-65%, PPS S10 roughness 0.8-1.5 µm (offset) and 0.6-1.0 µm (rot), density 1100-1250 kg / m3, brightness 70-] ···. 30 75% and opacity 89-94%.

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The general values for machine finished coated MFO paper can be as follows: basis weight 50-70 g / m2, Hunter gloss 25-70%, PPS S10 roughness 2.2-2.8 pm, density 900-950 kg / m3, lightness 70- 75% and opacity 91-95%.

General values for film coated offset (FCO) paper can be as follows: basis weight 40-70 g / m2, Hunter gloss 45-55%, PPS S10 roughness 1.5-2.0 pm, density 1000-1050 kg / m3, lightness 70 - 75% and opacity 91-95%.

General values for MWC (medium weight coated) paper may be as follows: basis weight 70 - 90 g / m2, Hunter gloss 65 - 75%, PPS S10 roughness 0.6 - 1.0 pm, density 1150 - 1250 kg / m3, brightness 70 - 75% and opacity 89-94%.

15 HWC (heavy weight coated) has a basis weight of 100-135 g / m2 and can be coated more than twice.

Pulp wood-free printing papers, i.e. fine papers, are uncoated and coated pulp-based printing papers with a mechanical pulp content of less than 10%.

• Unbleached pulp-based printing papers (WFU) contain bleached • birch pulp 55-80%, bleached coniferous pulp 0-30% and fillers 10 - 2: 30%. WFU values vary greatly in basis weight 50 - 90 g / m 2 (up to 2540 g / m 2), Bendtsen roughness 250-400 ml / min, brightness 86-92%, and guideline 83-98%.

* · 1: For coated pulp-based printing papers (WFCs), the coating amounts vary greatly according to requirements and applications. The following is a description of the 30-column values for single and double-coated pulp-based printing. : 2 sheets of paper: 90 g / m 2 coated once, Hunter glue 1 · 2 · 5 118351 65 - 80%, PPS S10 roughness 0.75 - 2.2 pm, lightness 80 88% and opacity 91-94% and double coated 130 g / m2, Hunter gloss 70-80%, PPS S10 roughness 0.65-0.95 µm, brightness 83-90% and opacity 95-97%.

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Release papers having a basis weight of 25 to 150 g / m2.

Other papers include e.g. packaging papers (Sackkraft), tissue papers (Tissue) and wallpaper (Wallpaper).

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Pulp, mechanical pulp and / or recycled pulp are used for the production of paperboard. The cartons can be divided into e.g. in the following main categories, according to their intended use: 15 Corrugated board with a liner and fluting.

Boxes are made of boxes, boxes for example. liquid packaging board (FBB = folding boxboard, LPB = liquid packaging board, WLOwhite-lined chipboard, SBS = solid bleached sulfite, SUS = solid un-20 bleached sulfite).

· «· * · · 1 · .. Graphic cartons mm. cards, maps, folders, covers, covers ...

It is therefore an object of the present invention to provide a method and apparatus for making • 1! 2 3's 25 security paper, more specifically, a fibrous web. and a method that utilizes it, which is well suited to a variety of paper and board grades.

The security paper according to the invention is characterized in that, when calendering the fibrous web, at least one side thereof is left with the desired pattern. Other areas without calendering, which are clearly distinct from the rest of the calendered surface of the fibrous web.

The method of making the security paper formed from the calendered fibrous web according to the invention is characterized in that at least one of the calendering steps of the fibrous web leaves at least to form the desired pattern-shaped areas on the fibrous web occurs in the final calendering step of a paper or board machine.

In order to achieve the objects of the invention, the device according to the invention is characterized in that recesses corresponding to the desired pattern-shaped areas for the surface of the fibrous web are traced on at least one calendering surface, so that the from the rest of the area.

20: * · [: The present invention provides numerous advantages over prior art techniques. It is very difficult to falsify paper or paperboard made by calendering engraved surfaces, since it is very difficult to obtain a structure that resembles an uncalendered surface on an already calendered surface.

The mechanical and simple method according to the invention is suitable for various types of uncoated or coated paper and board. grades. This method provides a very simple, fast and inexpensive way to make security paper and is a great online method! * · \. '. T for 30 paper machines.

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The solution is readily suited to, for example, the identification of packaging materials, such as tobacco boxes, cardboard CD cases, etc., which today are fairly counterfeited.

The invention will now be described in more detail with reference to the accompanying drawings, in which:

Fig. 1 is a schematic side view of an exemplary embodiment of a device according to the invention as a calender; 10

Fig. 2 is an oblique side view of a portion of the hl calender shown in Fig. 1, which in particular illustrates areas not calendered on the surface of the fibrous web.

Fig. 1 shows an apparatus according to the invention in the form of a belt calender comprising a metal calendering belt 2 which rotates about the guide rollers 3, at least some of which are movable to adjust the tension of the belt 2 as desired. The calendering belt 2 passes around a roll 5 arranged outside it, whereby a calendering area 20 is formed between the belt 2 and the roll 5. Recesses in the shape of the desired pattern are provided on the surface of the belt 2. The calenderable material web W passes through the calendering region, where it is subjected to the desired pressure pulse and thermal effect as a function of time, and the fibrous web is calendered except for the areas' i ,, which fall into the desired patterned stretches arranged on the belt. 6.

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The roller 5 used in the belt calender implemented according to the invention is, • ··) ···. as with nip roll 4, there may or may not be a deflection compensated roll and is selected from the group consisting of: a flexible roll such as a polymer coated roll, a rubber coated roll or an elastomeric roll, a shoe roll , • · Thermal roll and fiber roll. In the embodiment shown in Fig. 1, the nip roll has 118351 8 shoe rolls. Correspondingly, instead of the metal belt described above, the calender belt 2 may also be e.g. a steel-reinforced rubber belt, a polymer belt, or a coated metal, rubber or polymer belt. The surface of the roll 5 may likewise be hard or soft.

Fig. 2 shows the belt calender of Fig. 1 on a larger oblique scale so that the non-calendered areas 7 corresponding to the recesses 6 arranged on the fibrous web W, corresponding to the recesses 6 in the shape of the desired pattern, can also be considered. is also provided in the desired shape on the surface of the roll 5 which acts as a matching member, whereby the non-calendered areas 7 are formed on both sides of the calenderable fiber web W. In Figure 2, the thickness or thickness differences of both fibrous web W, belt 2 and non-calendered areas, as well as depths of recesses 6 provided on belt 2 are exaggerated, and further the fiber web W and belt 2 outlets are aligned in different directions after calendering zone.

The method is preferably applicable to a metal belt calender, but it can also be well applied to other types of calendars such as soft calender, machine calender. 20 Calender, shoe calender or, for example, multi-nip calender. Most preferably, the security paper is produced in the final calendering step of the paper machine, whereby the surface of the uncalendered areas remains substantially unchanged.

It is conceivable that security paper can also be produced later after the fiber web cutting and packaging step, i.e. the final calendering of the fiber web is done by the paper machine itself and later, for example, ···: · ··: In case of cardboard used for product packaging, during printing of packaging prior to cutting * V, which allows the flexible production of security paper in 30 small batches according to special requirements.

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Claims (5)

1. Security paper, sorted by a calendered fiber web (W), characterized in that upon calendering of the fiber web (W), at least one side thereof, portions (7) corresponding to the desired pattern are left uncalcended, which are uncalaned. portions (7) are clearly distinguished from the other portions of the calendered fiber web (W) and that said at least one calendering step in the preparation of the security paper and generation of portions of the desired pattern in the fiber web (W) has been arranged to be made in paper or cardboard machine's last calendering step. 2. A method for making security papers of a calendered fiber web (W), characterized in that at least one of the calendering steps of the fiber web (W) is left on at least one side thereof (7) with the desired pattern, which uncalibrated portions (7) are distinguished. clearly from the other portions of the calendered fibrous web (W), and said at least one calendering step in the preparation of the security paper and the production of portions of the desired pattern in the fibrous web (W) has been arranged to take place in the final calendering stage 20 of the paper or cardboard machine. ·. 3. Calendars for making security paper of a fiber web (W), characterized in that recesses (6) corresponding to the portions for the desired patterns are arranged in the calender's at least one calender side. for the surface of the fibrous web (W), so that upon calendering of the fibrous web (W), the portions of the fibrous web (W) which end up at the recesses (6) become uncalibrated, which uncalibrated portions (7) appear clear from the other portions of the fiber web ♦ · · · · · · · · · · · · · · · · · · · · · · · · ··· · The blemishes according to claim 3 for the production of security papers formed by a calendered fiber web (W), characterized therein, by the calender have a strip (2) running around a guide member (3), outside of which a strip is arranged, at least one with the band forming a contact surface forming the motor member (5) such that between the belt (2) and the motor member (5) is formed the processing zone of the web, through which the web to be processed is passed, and that in the band (2) and / or the motor member (5) ) recesses are provided to generate portions (7) of the shape of the desired patterns in the fiber web (W) to be calendered. 5. Device according to claim 4, characterized in that the band (2) is a metal band. · * * • · »• 9 9 · · · · · ·· · · · · · · · ·· · 9 9 9 9 9 99 9 m • 99 9 9 9 m 99m 99 • · • ·· ·· · • 9 • · ·· * • · ® · · · ·· # 9 999 9 »9 9 999 9 9 9 9 9 9 9 9 999 9 9 9