An anti-counterfeiting fiber, a preparation method thereof, and anti-counterfeiting paper or cardboard

Abstract

An anti-counterfeiting fiber, a preparation method thereof, and anti-counterfeiting paper or paperboard. The anti-counterfeiting fiber is obtained by cutting a flat strip-shaped fiber with a knife; the geometric shape of the anti-counterfeiting fiber can ensure that after the paper is formed during the papermaking process, the cut surface is parallel to the paper surface; at least two materials A and B with different heat shrinkage rates are included on the cut surface of the anti-counterfeiting fiber. Materials A and B extend side by side along the length direction to form a heat-bendable bending section; in the length direction, the heat shrinkage rate of material A is greater than that of material B, and the heat-bendable direction of the bending section is bendable towards the inner surface of material A to form a bending deformation visual feature. The realization basis of the effect of the present invention is to utilize: multi-component melt spinning to produce a long strip + cutting the cross-sectional thin slice of the long strip with a knife (the thickness is usually not more than 0.2 mm) + the comprehensive effect of the visual feature reflecting the bending of the local section fiber formed by different heat-shrinkable materials on the cross-section.

Description

Technical Field

[0001] The present invention relates to the field of anti-counterfeiting technology, and particularly to an anti-counterfeiting fiber. Background Art

[0002] Adding special fibers as an anti-counterfeiting material to paper to make anti-counterfeiting paper is a widely used anti-counterfeiting measure. Most banknote papers in the world add anti-counterfeiting fibers during the papermaking process as an anti-counterfeiting measure. However, in order to distinguish ordinary paper on the market, the difficulty of papermaking is increased. Generally speaking, the combination of fiber color structure and shape structure is relatively simple, and the anti-counterfeiting fibers are easily imitated.

[0003] For example, a fluorescent anti-counterfeiting fiber with a linear multi-color segment is used in Indian banknotes. It is linear, and the preparation method is to cut a printed multi-color paper strip into fine segments. The combination of color and shape is too simple, and the anti-counterfeiting fiber is easily forged.

[0004] Although CN101135127 in the prior art also mentions combining materials with different elongation rates to form anti-counterfeiting fibers, since this fiber utilizes the visual characteristics formed in the length direction of fiber spinning, that is, after spinning, it is cut into long segments and the long segments of fibers are bent. What the human eye can see is the visual characteristics in the length direction of fiber spinning. Since the material in the length direction of spinning is continuous and cannot be changed, the visual effect after bending in the length direction of spinning is very single. For example, there can only be one bend, and there can only be continuous same colors along the length direction. It is impossible to achieve two or more bends in different bending directions, and even more impossible to achieve multiple different colors along the length direction of fiber spinning. This structure can achieve a very single combination of color and shape, and it is difficult to improve the anti-counterfeiting performance of the anti-counterfeiting fiber. Summary of the Invention

[0005] In order to solve the problems of the single combination of shape and color of anti-counterfeiting fibers in the prior art, insufficient anti-counterfeiting effect, and easy forgery, the present invention provides an anti-counterfeiting fiber, its preparation method, and anti-counterfeiting paper or cardboard. The spinning fiber of the anti-counterfeiting fiber utilizes the visual characteristics on the cross-section of the spinning fiber to achieve fiber bending on the cross-section, so as to achieve a richer combination of color and shape and high anti-counterfeiting performance.

[0006] The technical solution of the present invention is as follows:

[0007] An anti-counterfeiting fiber, characterized in that the anti-counterfeiting fiber is obtained by cutting a flat strip-shaped fiber; the geometric shape of the anti-counterfeiting fiber can ensure that after the anti-counterfeiting fiber forms paper during the papermaking process, the cut surface is parallel to the paper surface; at least two materials A and B with different thermal shrinkage rates are included on the cut surface of the anti-counterfeiting fiber, and materials A and B extend side by side along the length direction to form a bendable bending section; in the length direction, the thermal shrinkage rate of material A is greater than that of material B, and the bending direction of the bending section is bent towards the inner surface of material A, and the thermally bendable direction of the bending section is bendable towards the inner surface of material A to form a bending deformation visual feature. This includes both the case where materials A and B are adjacent and the case where there is a gap in the middle.

[0008] Preferably, the cross-section of the flat strip fiber is rectangular before bending.

[0009] Preferably, the cut surface includes two parallel surfaces with the same area in the longitudinal direction, namely material A and material B respectively.

[0010] Preferably, the anti-counterfeiting fiber includes at least two bending sections, and the bending directions of two adjacent bending sections are opposite.

[0011] Preferably, the thickness between two cut surfaces of the anti-counterfeiting fiber is less than the minimum distance between two parallel lines tangent to the outer contour of the anti-counterfeiting fiber on the plane of the cut surface. Specifically, the minimum distance refers to: assuming that the cut surface of the anti-counterfeiting fiber is the XY plane, placing the anti-counterfeiting fiber between two parallel lines on the XY plane, and each parallel line is tangent to the outer contour of the anti-counterfeiting fiber, the minimum distance between two parallel lines that meet these conditions among all two parallel lines. This can ensure that the cut surface of the anti-counterfeiting fiber is parallel to the paper surface after the paper is formed during the papermaking process.

[0012] Preferably, one or both of the two endpoints of the anti-counterfeiting fiber have color dots or / and there is at least one color dot between two bending sections, the cross-section of the color dot is larger than the cross-section of the fiber of the bending section, and the color dots are circular, square and / or hollow circles.

[0013] Preferably, the bending section is connected to a non-bending section, and the non-bending section is a single-component material.

[0014] Preferably, materials A and B have different visual features, such as colors.

[0015] An anti-counterfeiting paper or cardboard containing the above anti-counterfeiting fiber, characterized in that after the anti-counterfeiting fiber is incorporated into the paper or cardboard, the cut surface of the anti-counterfeiting fiber is parallel to the surface of the paper or cardboard.

[0016] A manufacturing method of any of the above anti-counterfeiting fibers, characterized by including the following steps:

[0017] Step 1: Fabricate a spinning die which at least contains a structure for spinning materials A and B side by side.

[0018] Step 2: Use a multi-component spinning machine to inject materials A and B with different heat shrinkage rates into the two side-by-side material component structures in the die respectively.

[0019] Step 3: Spin and form a long strip, and the material A and material B components form upper and lower layers in the length direction of the long strip.

[0020] Step 4: Cut along the cross-section of the long strip in the length direction to form strip-shaped fibers.

[0021] Step 5: The strip-shaped fibers form curved fibers.

[0022] Preferably, in Step 5, the strip-shaped fibers are put into hot water to form curved fibers.

[0023] Advantageous technical effects of the present invention:

[0024] The realization basis of the effects of the present invention is the combination of several conditions: multi-component melt spinning to produce a long strip + cutting the cross-section thin slice of the long strip (the thickness is usually not more than 0.2 mm) + the comprehensive effect of the visual characteristics reflecting the bending of the local section fibers formed by different heat shrinkage materials on the cross-section. It can not only achieve a single bend, but also multiple bends. In a bend section, there can be not only a single color, but also multiple side-by-side different colors. This not only improves the difficulty of imitating the anti-counterfeiting fiber itself, but also the special combination of different color sections and the shape of the bend section is very easy to distinguish the visual characteristics of the anti-counterfeiting fibers made by other current processes; there is currently no visual characteristic of the combined effect of the knife-cut surface visual characteristic and the bending deformation visual characteristic. The manufacturing process of this fiber not only has a different process from all other anti-counterfeiting processes, but also can create a visual characteristic that can distinguish all existing anti-counterfeiting fibers. Description of the Drawings

[0025] Figure 1-1 Shown is the schematic diagram of the knife-cut surface in Example 1;

[0026] Figure 1-2 Shown is the schematic diagram of the thickness-related limitation in Example 1;

[0027] Figure 2 Shown is the schematic diagram of the knife-cut surface in Example 2;

[0028] Figure 3 Shown is the schematic diagram of the knife-cut surface in Example 3;

[0029] Figure 4 Shown is the schematic diagram of the knife-cut surface in Example 4;

[0030] Figure 5The figure shows a schematic diagram of the knife cut surface of the anti-counterfeiting fiber incorporated into the paper being parallel to the paper surface;

[0031] Figure 6-1 The figure shows a schematic diagram of the knife cut surface of the fluorescent light-angle color-changing fiber;

[0032] Figure 6-2 The figure shows a cross-sectional view of the fluorescent light-angle color-changing fiber along the length direction;

[0033] Reference numerals:

[0034] 1 - Color dot 1, 2 - Color dot 2, 3 - Knife cut surface, 4 - Parallel lines. Detailed implementation manners

[0035] The present invention will be further described in detail below with reference to the accompanying drawings. The following shows the preferred embodiments of the present invention. It should be understood that those skilled in the art can modify the present invention described herein and still achieve the beneficial effects of the present invention. Therefore, the following description should be understood as a broad guidance for those skilled in the art and not as a limitation to the present invention.

[0036] It should be noted that the accompanying drawings are all in a very simplified form and use non-precise ratios, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0037] Embodiment 1

[0038] The anti-counterfeiting fiber in this embodiment is a fiber obtained by knife cutting from a flat long strip fiber, and the observation surface with anti-counterfeiting features is the knife cut surface 3; the knife cut surface 3 of the anti-counterfeiting fiber contains two materials A and B with different thermal shrinkage rates, and materials A and B extend side by side along the length direction to form a bendable bending section; in the length direction, the thermal shrinkage rate of material A is greater than that of material B, and the bending direction of the bending section is bent towards the inner surface of material A, as Figure 1-1 shown.

[0039] Each end of the anti-counterfeiting fiber has a color dot. The material selection of the color dot has no influence on the shape of the fiber. Color dot 1 is red, color dot 2 is blue, material A1 is red, and material B1 is cyan; fluorescent materials can also be added to color dot 1, color dot 2, material A1, and material B1.

[0040] The thickness between the two knife cut surfaces 3 on both sides of the anti-counterfeiting fiber is less than the minimum distance between two parallel lines tangent to the outer contour of the anti-counterfeiting fiber on the plane of the knife cut surface 3. Specifically, as Figure 1-2As shown, the minimum distance refers to: assuming that the cut surface of the anti-counterfeiting fiber is the XY plane, placing the anti-counterfeiting fiber between two parallel lines on the XY plane, and each parallel line is tangent to the outer contour of the anti-counterfeiting fiber. The minimum distance between the two parallel lines among all the two parallel lines that meet these conditions. The two parallel lines 4 in the figure are examples. It can be ensured that the cut surface of the anti-counterfeiting fiber after the paper is formed in the papermaking process is parallel to the paper surface. The prior art is the visual effect in the fiber spinning length direction, and the spinning process determines that the properties of each section of material must be the same in the spinning length direction. Therefore, it is impossible to insert the above-mentioned color dots in the spinning length defense line, while it can be achieved on the cross-section of the fiber as the visual surface.

[0041] Example 2

[0042] See Figure 2 , in this example, the anti-counterfeiting fiber has two bending sections and two color dots at both ends. Each bending section has two materials with different thermal shrinkage rates. One section is material A1 and material B1, and the other section is material A2 and material B2. In the length direction, the thermal shrinkage rate of material A1 is greater than that of material B1, and the thermal shrinkage rate of material A2 is greater than that of material B2. The bending directions of the two bending sections are opposite. Material A1 and material A2 can be the same or different, and the same is true for material B1 and B2.

[0043] Example 3

[0044] See Figure 3 , in this example, the anti-counterfeiting fiber has three bending sections and two color dots at both ends. Each bending section has two materials with different thermal shrinkage rates, which are material A1 and material B1, material A2 and material B2, and material A3 and material B3 respectively. In the length direction, the thermal shrinkage rate of material A1 is greater than that of material B1, the thermal shrinkage rate of material A2 is greater than that of material B2, and the thermal shrinkage rate of material A3 is greater than that of material B3. The bending directions of adjacent two bending sections are opposite. Compared with the prior art that can only achieve bending in the fiber spinning length direction and cannot achieve more than one bending effect, this example achieves two bending effects.

[0045] Example 4

[0046] See Figure 4 , in this example, the anti-counterfeiting fiber has a non-bending section and a bending section. The non-bending section is a single-component material C, and the single-component material C will not bend when heated. The bending section is similar to the bending section in Example 1.

[0047] Example 5

[0048] This embodiment is a kind of paper or the middle layer of cardboard, which adopts the foregoing embodiment and contains the anti-counterfeiting fibers described in the present invention. The cut surface of the anti-counterfeiting fibers is parallel to the paper surface.

[0049] Cardboard is usually composed of multiple pulp layers laminated together. For the anti-counterfeiting fibers distributed in the middle pulp layer of the cardboard, tearing the paper layer can conveniently reveal the distributed anti-counterfeiting fibers, as Figure 5 shown.

[0050] Example 6

[0051] Figure 6-1 The figure shows a schematic diagram of the cut surface of the fluorescence angle-changing fiber. Figure 6-2 The figure shows a cross-sectional view of the fluorescence angle-changing fiber along the length direction; Material B is a blue light-emitting material, and Material C is an excitation light-blocking material. For example, an ultraviolet absorber is added to Material C, and this material can block the excitation light from passing through visible light. Material A is a red light-emitting material. When the excitation light (such as 365nm ultraviolet light) irradiates the anti-counterfeiting fiber from the M direction, the light mainly irradiates Material B, and Material C blocks the excitation light from irradiating Material A. At this time, the human eye observes the anti-counterfeiting fiber as blue light at any position. Similarly, when the excitation light (such as 365nm ultraviolet light) irradiates the anti-counterfeiting fiber from the N direction, the light mainly irradiates Material A, and Material C blocks the excitation light from irradiating Material B. At this time, the human eye observes the anti-counterfeiting fiber as red light at any position.

[0052] Example 7

[0053] This embodiment is a manufacturing method of the anti-counterfeiting fiber in Example 1, including the following steps:

[0054] Step 1: Manufacture a spinning die, and the die contains a structure for spinning Materials A and B side by side.

[0055] Step 2: Use a multi-component melt spinning machine to inject Materials A and B with different thermal shrinkage rates into the two material component structures side by side in the die respectively.

[0056] Step 3: Spin and form a long strip, and the Material A and Material B components form upper and lower layers in the length direction of the long strip.

[0057] Step 4: Cut along the cross-section perpendicular to the length direction of the long strip to form strip-shaped fibers with a cut surface 3.

[0058] Step 5: Put the strip-shaped fibers into high-temperature hot water to form bent fibers.

[0059] In Step 4, the cross-section is perpendicular to the length direction of the long strip, or can have a certain inclination angle with the length direction of the long strip.

[0060] The basic principles, main features and advantages of the present invention have been shown and described above. Therefore, the above description is only an embodiment of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification is only the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention also includes various equivalent changes and improvements, and these changes and improvements will all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. An anti-counterfeiting fiber, characterized in that The anti-counterfeiting fiber is a fiber obtained by cutting a flat strip-shaped fiber; the geometric shape of the anti-counterfeiting fiber can ensure that after the anti-counterfeiting fiber forms paper during the papermaking process, the cut surface is parallel to the paper surface; at least two materials A and B with different thermal shrinkage rates are included on the cut surface of the anti-counterfeiting fiber, and materials A and B extend side by side along the length direction to form a heat-bendable bending section; In the length direction, the thermal shrinkage rate of material A is greater than that of material B, and the heat-bendable direction of the bending section is bendable towards the inner surface of material A to form a bending deformation visual feature. The anti-counterfeiting fiber includes at least two bending sections, and the bending directions of adjacent bending sections are opposite. The bending section is connected to a non-bending section, and materials A and B of each bending section are the same or different.

2. The anti-counterfeiting fiber according to claim 1, wherein The cut surface includes two parallel surfaces with the same area longitudinally, namely material A and material B respectively.

3. The anti-counterfeiting fiber according to claim 1, characterized in that The thickness between the two cut surfaces of the anti-counterfeiting fiber is less than the minimum distance between two parallel lines tangent to the outer contour of the anti-counterfeiting fiber on the plane of the cut surface.

4. The anti-counterfeiting fiber according to claim 1, characterized in that The length of the bending section of the anti-counterfeiting fiber is greater than 3 times the maximum dimension of the cross-section of the bending section.

5. The anti-counterfeiting fiber according to claim 1, characterized in that The length of a single bending section fiber is greater than 1 mm.

6. The anti-counterfeiting fiber according to claim 1, wherein One or both of the two ends of the anti-counterfeiting fiber have color dots, and / or there is at least one color dot between two bending sections. The color dots are circular or square.

7. The anti-counterfeiting fiber according to claim 6, wherein The width of the color dot on the cut surface of the anti-counterfeiting fiber along the direction perpendicular to the length direction of the anti-counterfeiting fiber is greater than the width of the bending section fiber.

8. The anti-counterfeiting fiber according to claim 1, wherein The bending section is connected to a non-bending section, and the non-bending section is a single-component material.

9. The anti-counterfeiting fiber according to claim 8, wherein The length of the non-bending section is greater than 1 mm.

10. The anti-counterfeiting fiber according to claim 1, characterized in that Materials A and B have different visual features.

11. An anti-counterfeiting paper or cardboard containing the anti-counterfeiting fiber according to any one of claims 1-10, characterized in that After the anti-counterfeiting fiber is incorporated into paper or cardboard, the cut surface of the anti-counterfeiting fiber is parallel to the surface of the paper or cardboard.

12. A manufacturing method of the anti-counterfeiting fiber according to any one of claims 1-10, characterized in that It includes the following steps: Step 1: Make a spinning die, and the die contains at least a structure for spinning materials A and B side by side; Step 2: Use a multi-component spinning machine to inject materials A and B with different thermal shrinkage rates into the two material component structures side by side in the die respectively; Step 3: Spin and form a long strip, and materials A and B form upper and lower layers in the length direction of the long strip; Step 4: Cut along the cross-section in the length direction of the long strip to form strip-shaped fibers; Step 5: The strip-shaped fibers form bent fibers.

13. The method according to claim 12, wherein In Step 5, the strip-shaped fibers are put into high-temperature hot water to form bent fibers.

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