JP2893312B2 - Manufacturing method of anti-counterfeit paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing forgery prevention paper in which strips are unevenly distributed on the surface of a base paper.

[0002]

2. Description of the Related Art Recently, the accuracy of copying machines has been remarkably improved, and in particular, the spread of color copying machines has facilitated forgery of various securities. To prevent this, various anti-counterfeiting means have been considered, but one of them is to utilize the fact that current copiers cannot reproduce brilliant ones, for example, metallic colors or interference colors. There is something.

[0003]

SUMMARY OF THE INVENTION For example, Japanese Utility Model Application Laid-Open No. 58-1
As proposed in Japanese Patent No. 68754, there is a proposal of a non-copyable paper by a copying machine in which a bright plate such as aluminum foil having a remarkable metal tone is provided on the upper surface of a base paper, and a character pattern is provided on the bright plate surface. . When this is copied, the character pattern applied to the paper surface becomes unreadable because the foil surface is darkened and copied when light is irradiated from the copying machine. This sheet has the advantage that copying itself cannot be performed (the copy cannot be read), but has the disadvantage that the metallic color is emphasized too much because the area of the glittering plate occupying the sheet is so uncomfortable. In addition, there are other problems, such as a complicated paper manufacturing process, which inevitably increases the cost, and difficulty in recovering papermaking fibers from waste paper.

The present inventors have paid attention to the fact that if a copy is made in a different hue from that of the original document even when copied by a color copying machine, it is easy to determine whether the copy is genuine or not. The study was proceeded with the aim of solving the problems, and an application for anti-counterfeit paper was filed as Japanese Patent Application No. 5-11409. The gist of the present application is to provide a forgery-preventing paper in which glittering strips are ubiquitously provided on the surface of the base paper, wherein the strips have a performance capable of adhering to the base paper in the paper making process. Anti-counterfeit paper. This anti-counterfeiting paper is required to have a predetermined area (small area for gift certificate etc.) containing a predetermined number or more of strips. How to distribute the pieces evenly over the base paper. The present inventors have further studied and filed an application for a method for producing such anti-counterfeit paper.

[0005] On the other hand, anti-counterfeit paper in which fibers or the like which emit a fluorescent color upon irradiation with ultraviolet rays are known. For example, Japanese Patent Publication No. 56-16238 describes anti-counterfeit paper made by mixing fluorescently-stained fiber with non-fluorescent-stained fiber. The fluorescent dyed fibers in the paper are uniformly distributed inside.

[0006] Depending on the use of the forgery prevention paper, it may be preferable that the above-mentioned strips and fibers are not uniformly distributed on the entire surface of the paper, but are unevenly distributed in the paper flow direction.
For example, when considering the use of a gift certificate (generally, a size of 160 mm × 70 mm), if strips are unevenly distributed in a certain position on the paper in a streak shape, this portion is outlined (not printed). Part) or light-colored printing can be considered, which makes it easier to confirm the strip. An object of the present invention is to provide a method for producing a forgery prevention paper in which strips are unevenly distributed on the surface of the paper as described above.

[0007]

The present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view for explaining a strip sprinkling apparatus used in the present invention, and shows an example in which the apparatus is installed on a papermaking net of a fourdrinier paper machine. FIG. 2 is a partially enlarged sectional view thereof. The present invention uses a strip sprinkler comprising a storage tank 1, a stirring blade 2 installed in the storage tank 1, and an inclined plate 3 attached diagonally downward from the end of the storage tank in the traveling direction of the papermaking net W. Then, the aqueous suspension 5 of the strips is supplied into the storage tank, and the aqueous suspension of the strips is overflowed to the upper part of the inclined plate 3 by the rotation of the stirring blades 2. Guide the paper before forming the paper layer on the papermaking net or the wet paper web 6 in a streak form and sprinkle the paper, or just before or immediately after the circular cylinder of the circular paper machine sinks into the stock suspension. This is a method for producing anti-counterfeit paper, characterized by sprinkling paper in the form of a streak around a papermaking net.

[0008] The storage tank 1 is manufactured by an arbitrary method, such as manufacturing into a predetermined shape using a plate of wood, metal, synthetic resin, or the like, or manufacturing by injection molding into a predetermined shape using a synthetic resin. I do. In addition to the box shape as shown in the figure, any shape such as a round bottom shape or a box with a slanted side surface can be adopted.

A stirring blade 2 is installed in the storage tank 1 to uniformly stir the aqueous suspension of the strip supplied to the storage tank. The water suspension of the small pieces is supplied by a method such as installing a supply pipe 6 for the water suspension of the small pieces at the upper portion of the storage tank as shown in FIGS. The provision of the stirring blade is the greatest feature of the present invention. Without this, since the water suspension of the strip does not uniformly overflow on the upper part of the inclined plate, the distribution density in each stripe of the strip greatly fluctuates. , Is a major disadvantage in quality.
Although the supply of the water suspension 4 of the strips is not shown in the figure, a hole may be formed in the side surface of the storage tank, and a supply pipe may be connected to the hole to supply the suspension. A plurality of supply pipes are preferably provided in order to make the dispersion of the strips uniform.

The shape of the blade of the stirring blade 2 can be adopted as long as it has a function of uniformly overflowing the aqueous suspension of the small pieces supplied to the storage tank on the inclined plate by the rotation of the stirring blade. For example, a shape in which a number of screw-type stirring blades are attached to a shaft of metal or the like, a shape in which a plurality of stirring blades made of a flat elongated plate are attached to the shaft, a plurality of stirring blades made of a bent plate are attached to the shaft. Typical examples include a shape in which a plurality of stirring blades each of which is attached to a shaft, a metal tube attached to a shaft, and a flat elongated plate attached to the metal tube. The shaft 21 is exposed outside the storage tank as shown in FIG.
The motor can be rotated using a motor M or the like whose rotation speed can be changed.

The inventors of the present invention have studied the mounting angle of the stirring blade with respect to the shaft. As shown in FIG. 3, a metal tube 22 is mounted on the shaft 21 and the metal tube is formed of a flat elongated plate. Among the shapes having a plurality of stirring blades attached, the tip of the stirring blade 2 is the inclined plate 3 of the storage tank.
When the angle of inclination of the stirring blade at the upper position on the side is the same as or close to the angle of attachment of the inclined plate, the uniformity of the overflow of the water suspension of the strip to the upper part of the inclined plate is improved. It turned out to be the best. The reason for this is that, as shown in FIG. 3, when the water suspension of the strip is forcibly overflowed onto the inclined plate 3 by the rotation of the stirring blade 2, the mounting angle of the inclined plate 3 and the mounting angle of the stirring blade If the angles are the same or close to this, the water suspension of the strips will smoothly overflow to the inclined plate side.

The inclined plate 3 is attached obliquely downward in the traveling direction of the papermaking net W from the end of the storage tank. The water suspension of the strip is overflowed on the upper part of the inclined plate, and then the suspension is sprinkled on a stock or wet paper 6 before forming a paper layer on a papermaking net. As an example of a method of sprinkling the water suspension of the strip in a streak shape, as shown in FIG. From the bottom to the bottom. In the figure, only two rows of weirs are shown, and are omitted thereafter. The shape of the weir may be any shape other than the illustrated one, such as a straight shape from the upper part to the lower part of the inclined plate, as long as the water suspension of the strip can be sprinkled in a streak shape. In another example, as shown in FIG. 4, a groove G is provided in the inclined plate 3 so that the flow of the water suspension of the strip becomes narrower from the upper portion to the lower portion of the inclined plate. The groove has a triangular cross-section in addition to the rectangular cross-section as shown.
Any shape such as a wave shape can be adopted. In another example, as shown in FIG. 5, a pipe P is provided on the inclined plate 3 so that the flow of the water suspension of the strip becomes narrower from the upper portion to the lower portion of the inclined plate. An arbitrary shape such as a rectangle, a triangle, a circle, and an ellipse can be adopted as a cross-sectional shape of the pipe.

The inclined plate 3, weir D, and pipe P are made of a plate or pipe of wood, metal, plastic, or the like.
Usually, a plurality of weirs, grooves and pipes are provided in the lateral direction of the paper. The interval is set arbitrarily according to the required characteristics of the paper. The width to be sprinkled in the form of a stripe is also set arbitrarily according to the required characteristics of the paper. Although not shown in FIGS. 1 to 5, in order to prevent the water suspension of the small pieces from scattering to the outside of both ends of the inclined plate, it is preferable to provide walls at both ends with a plastic plate or the like.

The storage tank 1 has a front chamber 11 as illustrated in FIG.
And the rear chamber 12, and not only of a structure in which the strip suspension supplied to the front chamber 11 is stirred and homogenized and then guided to the rear chamber 12, but also divided into a single chamber without dividing into the front chamber and the rear chamber. It can also be structured. According to the results of the study by the present inventors, it was found that the two-chambered structure had better strip uniformity. In order to improve the dispersion of the small pieces supplied to the front chamber, stirring blades can be provided, and any of the above-mentioned shapes can be used. 1 and 2 show an example in which the suspension is guided from the lower part of the front chamber 11 to the rear chamber 12, but the suspension is guided to the rear chamber by overflowing a partition plate near the center although not shown. The shape of the storage tank having the structure can be adopted as another example.

The strip sprinkler having the above-described structure is installed on a paper net of a fourdrinier paper machine by, for example, hanging from a ceiling, and before forming a paper layer of a stock suspension on the paper net (papermaking). The water suspension of the strips is sprinkled on a stock or wet paper web (after the water has run out and a paper layer has been formed) 5 before drainage occurs on the net. FIG. 1 shows a state of sprinkling before forming the paper layer. Sprinkling fine particles on the wet paper after forming the paper layer increases the tendency of the formation to deteriorate, and sprinkling before forming the paper layer hardly deteriorates the formation, but the formulation of the stock and the required properties of the paper The position at which the strip is sprinkled is arbitrarily selected.

An apron 7 of a film or sheet made of a flexible material such as polyvinyl chloride resin or polyester resin can be attached to the tip of the inclined plate 3. Thereby, the effect of preventing the formation of the paper from being deteriorated when the water suspension of the strips is sprinkled in a streak shape can be further enhanced.

The object of the present invention can be achieved even if the above-described strip sprinkler is installed in a round paper machine. in this case,
Immediately before or immediately after the mesh cylinder dive into the stock suspension in the vat, the aqueous suspension of the strips may be sprinkled in the form of a streak near the papermaking net. The strips sprinkled in a streak form accumulate on the papermaking net in a streak form. When paper is made with a circular paper machine, most of the paper layer is formed in the initial stage when the paper net sinks into the vat. Or, it becomes unevenly distributed near the surface.

The strip used in the present invention may be a colored fiber, a fiber to which a fluorescent dye is attached, a fiber to which a fluorescent pigment is attached,
Fibers with metal powder, flaked metal foil, flaked metal vapor-deposited film, flaked pearl pigment coated paper, flaked fluorescent pigment coated paper, proposed by the present inventors first Any of the strips for anti-counterfeit paper described in Japanese Patent Application No. 5-11409 described above, that is, strips having glitter can be used.

The anti-counterfeit paper of the present invention is first of all bleached softwood kraft pulp (NBKP), bleached hardwood kraft pulp (LBKP) and bleached softwood sulphite pulp (NBS).
P), papermaking pulp such as thermomechanical pulp (TMP), etc., to which dry paper strength enhancer, wet paper strength enhancer, sizing agent, fixing agent, retention improver, drainage improver,
Papermaking auxiliary materials such as an antifoaming agent, a dye, a coloring pigment, and a fluorescent agent are appropriately used in combination, and usually have a freeness of 550 to 250 ml.
S. F. Papermaking using a fourdrinier paper machine or a round paper machine.

The small pieces are pre-filled with water in a tank or the like, mixed with the small pieces, gently stirred with a stirrer, and guided to a sprinkler using a flow pump or the like. At this time, in order to promote uniform dispersion of the strips, a water and a tackifier such as polyethylene oxide and polyethylene oxide may be appropriately used. The aqueous suspension of the strips is then sprinkled in a streak using the strip sprinkler as described above.

Next, the wet paper is dewatered and dried according to a conventional method. The paper is clarified using a conventionally known method, and starch, polyvinyl alcohol, various surface sizes and the like are printed on the paper with a size press device or the like. Coating is also possible. Further, if necessary, a machine calendering treatment or a super calendering treatment is performed to appropriately improve the surface smoothness.

[0022]

The following examples are given, but in the examples, parts by weight,
All weight% means dry weight part and dry weight%. Example 1 Both sides of a size paper having a basis weight of 35 g / m <2>
Using a paint composed of 100 parts by weight of pearl pigment of mica powder having a titanium oxide coverage of 28% and 200 parts by weight of polyvinyl alcohol, using an air knife coater, one side of 7 g / m2.
Coated two by two. Then 3mm ×
A 4 mm rectangular strip was produced. 20 parts by weight of NBKP and 80 parts by weight of LBKP were added to 350 ml C.I. S. F. 10 parts by weight of clay, 0.3 parts by weight of a paper strength agent (trade name "Polystron 191", manufactured by Arakawa Chemical Industry Co., Ltd.), a sizing agent (trade name "Size Pine E", Arakawa 1.0 part by weight (manufactured by Chemical Industry Co., Ltd.) and an appropriate amount of a sulfuric acid band were added to prepare a stock. Using a Fourdrinier paper machine, basis weight 110 g / m
When the base paper of No. 2 was formed, the above-mentioned strips were streaked on the stock immediately after slicing using the sprinkler shown in FIG. 1 (the interval between weirs was set to 160 mm, and placed at equal intervals in the horizontal direction). Sprinkled on. Thereafter, dehydration was carried out according to a conventional method, and drying was carried out using a multi-cylinder cylinder dryer. The obtained anti-counterfeit paper is 160
It was unevenly distributed on the paper surface with a width of about 30 mm at mm intervals. When this paper was copied using a color copier (trade name “Cannon Pixel”), the glitter color of the strip was not reproduced, and the difference between the two (the original and the copy) was clearly recognized by visual inspection.

EXAMPLE 2 250 parts by weight of 20 parts by weight of NBKP and 80 parts by weight of LBKP
C. S. F. 10 parts by weight of clay, 0.3 parts by weight of a paper strength agent (trade name "Polystron 191", manufactured by Arakawa Chemical Industry Co., Ltd.), a sizing agent (trade name "Size Pine E", Arakawa 1.0 part by weight (manufactured by Chemical Industry Co., Ltd.) and an appropriate amount of a sulfuric acid band were added to prepare a stock. Three types of inks (trade name "Lumilight", manufactured by Shinloich Co., Ltd.), which fluoresce in red, blue, and yellow upon irradiation with ultraviolet rays, were applied to thin paper having a basis weight of 20 g / m2 at 15 g / m2, and dried. Thereafter, the mixture was defibrated separately using a household mixer to prepare a bundled fluorescent strip slurry. This was passed through an 8 mesh filter to remove large debris. The above strips were used to make a paper having a basis weight of 110 g / m 2 using the above-mentioned stock in a Fourdrinier paper machine.
Using the same sprinkler as in the above, sprinkles were sprinkled just before the mesh cylinder dipped into the stock suspension. Thereafter, dehydration was carried out according to a conventional method, and drying was carried out using a multi-cylinder cylinder dryer. In the obtained anti-counterfeit paper, the presence of strips is not clearly visible under ordinary light, and the red, blue, and yellow colors are obtained by irradiating ultraviolet rays (using a commercially available black light) under ordinary light. Strips emitting fluorescent color were visible.

[0024]

The present invention is configured as described above, and the following remarkable effects can be obtained. 1) Stripes can be unevenly distributed in the paper flow direction at predetermined intervals and widths. 2) The uneven distribution density of the strip in each muscle is almost uniform. This is based on the fact that the water suspension of the strip can uniformly overflow to the upper part of the inclined plate 3 by the stirring blades installed in the storage tank. 3) Since the strip exists on or near the surface of the paper, when a glittering strip is used, the strip is clearly visible without loss of the glitter, and the strip emits light when irradiated with ultraviolet rays. When a piece is used, forgery-preventing paper having a higher luminous intensity can be manufactured as compared with the conventional method in which a small piece exists inside the paper.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an example of a strip sprinkler used in the present invention.

FIG. 2 is a partially enlarged cross-sectional view thereof.

FIG. 3 is an example of a shape of a stirring blade.

FIG. 4 is a partial view of an example of a strip sprinkler in which a groove G is provided in an inclined plate 3;

FIG. 5 is a partial view of an example of a strip sprinkler in which a pipe P is provided on an inclined plate 3;

[Description of Signs] 1 Storage tank 2 Stirrer blade 3 Inclined plate attached diagonally downward from the end of the storage tank in the traveling direction of papermaking net W 4 Water suspension of strips 5 Paper before paper layer formation on papermaking net Material 6 Suspension supply pipe for water suspension of small pieces 7 Apron 11 Front chamber of storage tank 12 Rear chamber of storage tank 21 Shaft 22 Metal pipe D Weir G Groove M Motor P Pipe T Table roll W Papermaking net

Continuing from the front page (72) Inventor Masahito Sugimura 501, Honjuku, Nagaizumi-cho, Sunto-gun, Shizuoka Pref. Special Examiner in Paper Manufacturing Co., Ltd. Examiner Tadahiro Manada (56) References JP-A-7-145600 (JP, A) (58) Survey Field (Int.Cl. ⁶ , DB name) D21H 21 / 42,23 / 46,27 / 02

Claims (7)

(57) [Claims] 1. A strip sprinkler comprising a storage tank 1, a stirring blade 2 installed in the storage tank 1, and an inclined plate 3 attached diagonally downward from the end of the storage tank in the traveling direction of the papermaking net W. The water suspension 5 of the strip is used and supplied into the storage tank, and the water suspension of the strip is overflowed to the upper part of the inclined plate 3 by the rotation of the stirring blade 2, and the suspension is then machined. Guide the paper layer before forming the paper layer on the papermaking net of the machine or the wet paper web 6 and sprinkle it to make paper, or just before or immediately after the cylinder of the papermaking machine sinks into the stock suspension. A method for producing anti-counterfeit paper, characterized in that the paper is sprinkled in the form of a strip around a papermaking net. 2. A weir (ditch) D is provided on the inclined plate 3 so that the flow of the aqueous suspension of the strip becomes narrower from the upper part to the lower part of the inclined plate to form a paper layer on the papermaking net. 2. The method for producing anti-counterfeit paper according to claim 1, wherein the water suspension of the strip is sprinkled on the previous stock or wet paper 6 in a streak form. 3. A groove G in which the flow of the water suspension of the strip is narrowed from the upper part to the lower part of the inclined plate.
2. A method for producing anti-counterfeit paper according to claim 1, wherein the paper is sprinkled on a paper stock or wet paper 6 before forming a paper layer on a papermaking net in the form of a strip of water suspension. . 4. The inclined plate 3 is provided with a pipe P such that the flow of the aqueous suspension of the strip becomes narrower from the upper part to the lower part of the inclined plate, and the stock before the paper layer is formed on the papermaking net. 2. The method for producing a forgery prevention paper according to claim 1, wherein the water suspension of the strips is sprinkled on a wet paper web 6 to form a paper. 5. The storage tank is divided into a front chamber 11 and a rear chamber 12, and the aqueous suspension of the small pieces supplied to the front chamber 11 is stirred and homogenized and then guided to the rear chamber 12. Item 4. A method for producing a forgery prevention paper according to Item 1. 6. The stirring blade 2 to which the stirring plate 22 is attached at an angle close to the attachment angle of the inclined plate 3 with respect to the central shaft 21 is used.
A method for producing the forgery prevention paper according to the above. 7. The method according to claim 1, wherein an apron made of a flexible material is attached to a tip of the inclined plate.