阅读说明：本技术 光透水松纸及其制备方法 (Light permeable loose paper and preparation method thereof ) 是由 何金星 郭锦程 郭建宏 任金祥 夏会萍 何留 于 2021-09-17 设计创作，主要内容包括：本发明公开了一种光透水松纸及其制备方法,是在水松原纸层(1)的正面依次设有底色水性透明彩色油墨层(2)、水性防脱涂层(3)和高光光油层(4),反面设有单色醇性油墨层(5)而成。所述单色醇性油墨层(5)为标识防伪信息的文字或图案,文字或图案间隔3～10mm镜像设置于水松原纸层(1)的反面,每个图案或文字长3～10 mm,宽3～10mm。本发明通过采用组合凹版表印和里印方式,形成一种新的防伪印刷工艺技术,它通过使用透明度良好的印刷基材—素面介质纸,表明印刷透明油墨,反面隐藏凹版里印图文,在侧面亮光照射下,从正面可肉眼看到反面的图文,是一项经济实用的新型防伪印刷工艺技术。(The invention discloses light permeable loose paper and a preparation method thereof, wherein a ground color water-based transparent colorful ink layer (2), a water-based anti-dropping coating layer (3) and a high gloss oil layer (4) are sequentially arranged on the front side of a raw paper layer (1) of a pine, and a single color alcohol ink layer (5) is arranged on the back side of the raw paper layer. The single-color alcoholic printing ink layer (5) is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the tipping base paper layer (1) at intervals of 3-10 mm in a mirror mode, and each pattern or character is 3-10 mm long and 3-10 mm wide. The invention forms a new anti-counterfeiting printing process technology by adopting a combined gravure surface printing and inner printing mode, indicates that transparent printing ink is printed by using a printing substrate-plain medium paper with good transparency, intaglio inner printing pictures and texts are hidden on the back surface, and the pictures and texts on the back surface can be seen by naked eyes from the front surface under the irradiation of side surface bright light, thereby being an economical and practical novel anti-counterfeiting printing process technology.)

1. The light permeable loose paper comprises a raw tipping paper layer (1) and a printing layer, and is characterized in that a bottom color water-based transparent color ink layer (2), a water-based anti-drop coating layer (3) and a high light oil layer (4) are sequentially arranged on the front side of the raw tipping paper layer (1), and a single-color alcohol ink layer (5) is arranged on the back side;

the tipping base paper layer (1) adopts the quantitative 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance;

the water-based transparent colorful ink layer (2), the water-based anti-dropping coating layer (3) and the high gloss oil layer (4) are sequentially arranged on the front surface of the tipping raw paper layer (1) in a full-page superposition manner;

the single-color alcoholic printing ink layer (5) is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the tipping base paper layer (1) at intervals of 3-10 mm in a mirror mode, and each pattern or character is 3-10 mm long and 3-10 mm wide.

2. The light permeable loose paper according to claim 1, wherein the water transparent colored ink layer (2) is provided with 1-2 layers.

3. The light permeable loose paper according to claim 1, wherein the water transparent color ink does not contain titanium dioxide component and calcium carbonate component, and has low covering rate and high ink transparency; the material is prepared from the following raw materials in percentage by weight: 8-12% of pigment, 50-55% of acrylate copolymer, 2-4% of silicon dioxide, 22-36% of ethanol, 8-10% of water and 0.2-0.6% of auxiliary agent.

4. The light permeable loose paper according to claim 2, wherein the water transparent color ink does not contain titanium dioxide component and calcium carbonate component, and has low covering rate and high ink transparency; the material is prepared from the following raw materials in percentage by weight: 8-12% of pigment, 50-55% of acrylate copolymer, 2-4% of silicon dioxide, 22-36% of ethanol, 8-10% of water and 0.2-0.6% of auxiliary agent.

5. The light permeable pine paper according to any one of claims 1 to 4, wherein the aqueous anti-peeling coating is prepared from the following raw materials in percentage by weight: 20 to 30 percent of polyvinyl butyral, 0.6 to 0.9 percent of talcum powder, 0.07 to 0.16 percent of polyethylene wax, 58 to 72 percent of ethanol, 4 to 8 percent of water and 0.1 to 0.4 percent of auxiliary agent.

6. A method of making the light permeable paper of any one of claims 1 to 5, comprising the steps of:

a. printing 1-2 groups of water-based transparent colorful ink layers (2) on a tipping raw paper layer (1) by adopting a gravure printing process, wherein the printing pressure is 3-6bar, and the printing speed is 120-150 m/min; the solid content of the water-based transparent colorful ink layer is 20-30%, the viscosity (Chaishi cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm; printing patterns by using an electrostatic ink absorption device;

b. after all the water-based transparent colorful ink layers (2) are printed, a layer of water-based anti-dropping coating (3) is printed; the solid content of the aqueous anti-falling coating (3) is 5-10%, the viscosity (Chaishi cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm; printing patterns by using an electrostatic ink absorption device;

c. printing a high gloss oil layer (4) on the surface of the water-based anti-falling coating (3), wherein the number of gravure roller lines is 80L/cm; printing patterns by using an electrostatic ink absorption device;

d. drying: the drying temperature of the drying tunnel is respectively 150 +/-10 ℃ to 140 +/-5 ℃ to 150 +/-10 ℃;

e. after the front side is printed and rolled, a single-color alcohol ink layer (5) is printed on the back side by using a pattern and a character printing plate through a single-color intaglio printing plate, wherein the alcohol ink contains a titanium dioxide component and a calcium carbonate component, and has high coverage rate and low transparency; the solid content of the alcoholic ink is 20-30%, and the viscosity (Chaishi cup (immersion type) 3#, 25 ℃) is 25-30 s; the number of gravure roller lines is 70L/cm; the pattern and characters of the single-color alcohol ink layer (5) adopt a hidden design inner printing mode, the inner printing plate making process and the surface printing plate making process are completely the same, but the image on the printing plate is a reverse image during the surface printing plate making process, the printed image is a positive image, the inner printing plate text is a positive image, and the printed image is a reverse image.

Technical Field

The invention belongs to the field of paper printing, and particularly relates to anti-counterfeiting tipping paper with hidden pictures and texts printed from the front side to the back side and a preparation method thereof.

Background

The tipping paper for cigarette is an important raw material for producing cigarette, and is characterized by that it uses tipping base paper for cigarette as base material, and adopts the steps of preprinting design, printing processing and after-printing treatment, etc. to finally connect the filter tip with cigarette.

The traditional tipping paper is mainly characterized in that patterns, characters and other information are arranged at a specific position of the tipping paper by means of multicolor printing, gold stamping and the like, and a specific decorative effect is formed by matching with the ground color of the tipping paper. In addition, in order to avoid that counterfeit products are too good and damage the legitimate rights and interests of regular products, the tipping paper needs to be subjected to corresponding anti-counterfeiting treatment. The common anti-counterfeiting processing mode mainly adopts laser anti-counterfeiting codes, the effect is good, but the production cost is higher, so the anti-counterfeiting processing mode is improved, the cost is reduced under the condition of realizing the anti-counterfeiting function, and the income is improved.

Disclosure of Invention

In order to solve the problems, the invention aims to provide light permeable pine paper and a preparation method thereof, which adopts a high-smoothness and high-transparency functional printing substrate material-plain medium Chinese cypress base paper, and an innovative printing mode-combined gravure surface printing and inner printing anti-counterfeiting printing process technology to ensure that the light permeable pine paper has hidden pictures and texts printed on the front side and the back side of the Chinese cypress paper by naked eyes through the irradiation of bright light from the side.

In order to achieve the purpose, the light permeable loose paper is formed by sequentially arranging a ground color water-based transparent colorful ink layer 2, a water-based anti-dropping coating layer 3 and a high gloss oil layer 4 on the front side of a raw paper layer 1 of a pine and arranging a single-color alcohol ink layer 5 on the back side.

The tipping base paper layer 1 is quantitatively 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance.

The water-based transparent colorful ink layer 2, the water-based anti-dropping coating 3 and the high gloss oil layer 4 are sequentially arranged on the front surface of the tipping raw paper layer 1 in a full-page superposition manner.

The single-color alcoholic ink layer 5 is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the Chinese cypress raw paper layer 1 at intervals of 3-10 mm in a mirror mode, and each pattern or character is 3-10 mm long and 3-10 mm wide.

Preferably, the water-based transparent colorful ink layer 2 is set to be 1-2 layers.

The water-based transparent color ink does not contain titanium dioxide and calcium carbonate, has low covering rate and high ink transparency; the material is prepared from the following raw materials in percentage by weight: 8-12% of pigment, 50-55% of acrylate copolymer, 2-4% of silicon dioxide, 22-36% of ethanol, 8-10% of water and 0.2-0.6% of auxiliary agent. The water-based transparent ink colorant is completely or mostly made of high-grade transparent pigment, the connecting material is made of high-grade transparent resin as a main raw material and other various auxiliary agents through fine grinding, and the water-based transparent ink has very low covering power and extremely high transparency. The fineness of the transparent ink is finely ground to be less than 10 microns, so that the covering power and the transferability of the transparent ink are good, and the transparent ink has the characteristics of high viscosity, high transparency, high brightness, good leveling property, bright color, firm adhesion, strong tinting strength and the like. It is especially suitable for printing raw tipping paper with plain medium, which has high smoothness and transparency, and the transparency of the transparent ink is determined by pigment, binder and assistant.

The water-based anti-falling paint is prepared from the following raw materials in percentage by weight: 20 to 30 percent of polyvinyl butyral, 0.6 to 0.9 percent of talcum powder, 0.07 to 0.16 percent of polyethylene wax, 58 to 72 percent of ethanol, 4 to 8 percent of water and 0.1 to 0.4 percent of auxiliary agent. The aqueous anti-drop coating adopts polyvinyl butyral which is a resin material with high transparency and strong adhesive force, can prevent a printing color layer from being decolored when used for gravure, and simultaneously, polyethylene wax is added as a carrier of the pigment, so that the wear resistance of the ink is improved, the dispersibility and the anti-settling effect of the pigment and the filler are improved, and a printed product has good luster, transparency and stereoscopic impression.

The invention also provides a preparation method of the light permeable loose paper, which comprises the following steps:

a. printing 1-2 groups of water-based transparent colorful ink layers 2 on a tipping raw paper layer 1 by adopting a gravure printing process, wherein the printing pressure is 3-6bar, and the printing speed is 120-150 m/min; the solid content of the water-based transparent colorful ink layer is 20-30%, the viscosity (Chai cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

b. After printing all the water-based transparent colorful ink layers 2, printing a layer of water-based anti-dropping coating 3 to prevent the color layers from being decolored and keep the color and the glossiness of the color layers; the solid content of the water-based anti-falling coating 3 is 5-10%, the viscosity (Chaishi cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

c. And printing a high gloss oil layer 4 on the surface of the water-based anti-release coating 3 to increase the brightness of the color layer, wherein the number of gravure rollers is 80L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

d. Drying: the drying temperature of the drying tunnel is respectively 150 +/-10 ℃ to 140 +/-5 ℃ to 150 +/-10 ℃.

e. After the front side is printed and rolled, a single-color alcohol ink layer 5 is printed on the back side by using a pattern and a character printing plate through a single-color gravure, wherein the alcohol ink contains a titanium dioxide component and a calcium carbonate component, and has high coverage rate and low transparency; the solid content of the alcoholic ink is 20-30%, and the viscosity (Chaishi cup (immersion type) 3#, 25 ℃) is 25-30 s; the number of gravure roller lines was 70L/cm. The single-color alcohol ink layer 5 has the pattern and characters in hidden design, the inner printing plate making process is completely the same as the surface printing plate making process, but the image on the printing plate is reverse image during the surface printing plate making process, the printed image is positive image, the inner printing plate text is positive image, and the printed image is reverse image. The printed characters and patterns are gravure printed by the single-color low-viscosity alcohol ink, the smoothness of the back of the paper is low, the printed characters and patterns are light and fuzzy, and the hidden characters and patterns ensure that the back is not displayed under the condition of no bright light irradiation and cannot be seen by naked eyes from the front, so that the aim of anti-counterfeiting printing is fulfilled. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

Has the advantages that: the invention adopts a large amount of water-based ink for printing, reduces the emission of printing organic volatile components, is green for printing, is environment-friendly, and meets the safety regulation of tobacco materials.

By adopting a combined gravure surface printing and inner printing mode, a novel anti-counterfeiting printing process technology is formed, transparent printing ink is printed by using a printing substrate with good transparency, plain medium paper is used for hiding gravure inner printing pictures and texts, and the pictures and texts on the reverse side can be seen by naked eyes from the front under the irradiation of side bright light, so that the novel anti-counterfeiting printing process technology is economical and practical.

The invention uses the plain medium paper with good transparency and the water-based transparent ink, and the combination of the plain medium paper and the water-based transparent ink can generate ideal appearance effect, thereby utilizing the advantages of unique appearance, special effect of transparent laser effect, good glossiness and transparency and high smoothness of the innovative material of the plain medium paper with good transparency to the greatest extent.

Drawings

FIG. 1 is a schematic view of the structure of the present invention.

Fig. 2 is a schematic structural diagram of embodiment 2 of the present invention.

FIG. 3 is a schematic diagram of the front display image structure under the irradiation of light from the side.

FIG. 4 is a schematic view of a reverse side display image structure under the irradiation of light from the side.

In the figure: the anti-dropping printing ink comprises a Chinese cypress raw paper layer 1, a water-based transparent colored ink layer 2, a water-based anti-dropping coating 3, a high gloss oil layer 4 and a single-color alcohol ink layer 5.

Detailed Description

Example 1: the light permeable loose paper is formed by sequentially arranging a ground color water-based transparent color ink layer 2, a water-based anti-dropping coating layer 3 and a high gloss oil layer 4 on the front side of a raw paper layer 1 of the pine and a single color alcohol ink layer 5 on the back side.

The tipping base paper layer 1 is quantitatively 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance.

The water-based transparent colorful ink layer 2, the water-based anti-dropping coating 3 and the high gloss oil layer 4 are sequentially arranged on the front surface of the tipping raw paper layer 1 in a full-page superposition manner.

The single-color alcoholic ink layer 5 is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the tipping base paper layer 1 at intervals of 5mm in a mirror image mode, and each pattern or character is 6mm long and 6mm wide.

Preferably, the aqueous transparent colored ink layer 2 is provided as 2 layers.

Example 2: the light permeable loose paper is formed by sequentially arranging a ground color water-based transparent color ink layer 2, a water-based anti-dropping coating layer 3 and a high gloss oil layer 4 on the front side of a raw paper layer 1 of the pine and a single color alcohol ink layer 5 on the back side.

The tipping base paper layer 1 is quantitatively 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance.

The water-based transparent colorful ink layer 2, the water-based anti-dropping coating 3 and the high gloss oil layer 4 are sequentially arranged on the front surface of the tipping raw paper layer 1 in a full-page superposition manner.

The single-color alcoholic ink layer 5 is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the tipping base paper layer 1 at intervals of 8mm in a mirror image mode, and each pattern or character is 10mm in length and 10mm in width.

Preferably, the aqueous transparent color ink layer 2 is provided as 1 layer.

The water-based transparent color ink does not contain titanium dioxide and calcium carbonate, has low covering rate and high ink transparency; the material is prepared from the following raw materials in percentage by weight: 8% of pigment yellow, 51.8% of acrylate copolymer, 2% of silicon dioxide, 30% of ethanol, 8% of water and 0.2% of auxiliary agent. The water-based transparent ink colorant is completely or mostly made of high-grade transparent pigment, the connecting material is made of high-grade transparent resin as a main raw material and other various auxiliary agents through fine grinding, and the water-based transparent ink has very low covering power and extremely high transparency. The fineness of the transparent ink is finely ground to be less than 10 microns, so that the covering power and the transferability of the transparent ink are good, and the transparent ink has the characteristics of high viscosity, high transparency, high brightness, good leveling property, bright color, firm adhesion, strong tinting strength and the like. It is especially suitable for printing raw tipping paper with plain medium, which has high smoothness and transparency, and the transparency of the transparent ink is determined by pigment, binder and assistant.

The water-based anti-falling paint is prepared from the following raw materials in percentage by weight: 20% of polyvinyl butyral, 0.8% of talcum powder, 0.13% of polyethylene wax, 70.8% of ethanol, 7% of water and 0.27% of auxiliary agent. The aqueous anti-drop coating adopts polyvinyl butyral which is a resin material with high transparency and strong adhesive force, can prevent a printing color layer from being decolored when used for gravure, and simultaneously, polyethylene wax is added as a carrier of the pigment, so that the wear resistance of the ink is improved, the dispersibility and the anti-settling effect of the pigment and the filler are improved, and a printed product has good luster, transparency and stereoscopic impression.

Example 3: the light permeable loose paper is formed by sequentially arranging a ground color water-based transparent color ink layer 2, a water-based anti-dropping coating layer 3 and a high gloss oil layer 4 on the front side of a raw paper layer 1 of the pine and a single color alcohol ink layer 5 on the back side.

The tipping base paper layer 1 is quantitatively 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance.

The water-based transparent colorful ink layer 2, the water-based anti-dropping coating 3 and the high gloss oil layer 4 are sequentially arranged on the front surface of the tipping raw paper layer 1 in a full-page superposition manner.

The single-color alcoholic ink layer 5 is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the Chinese cypress raw paper layer 1 at intervals of 3-8 mm in a mirror mode, and each pattern or character is 3-10 mm long and 3-10 mm wide.

Preferably, the aqueous transparent colored ink layer 2 is provided as 2 layers.

The water-based transparent color ink does not contain titanium dioxide and calcium carbonate, has low covering rate and high ink transparency; the water-based transparent color ink in contact with the tipping base paper layer 1 is prepared from the following raw materials in percentage by weight: 12% of pigment yellow, 50% of acrylate copolymer, 4% of silicon dioxide, 25% of ethanol, 8.5% of water and 0.5% of auxiliary agent. The superposed water-based transparent color ink is prepared from the following raw materials in percentage by weight: 11% of pigment red, 52% of acrylate copolymer, 3.4% of silicon dioxide, 24% of ethanol, 9% of water and 0.6% of auxiliary agent. The water-based transparent ink colorant is completely or mostly made of high-grade transparent pigment, the connecting material is made of high-grade transparent resin as a main raw material and other various auxiliary agents through fine grinding, and the water-based transparent ink has very low covering power and extremely high transparency. The fineness of the transparent ink is finely ground to be less than 10 microns, so that the covering power and the transferability of the transparent ink are good, and the transparent ink has the characteristics of high viscosity, high transparency, high brightness, good leveling property, bright color, firm adhesion, strong tinting strength and the like. It is especially suitable for printing raw tipping paper with plain medium, which has high smoothness and transparency, and the transparency of the transparent ink is determined by pigment, binder and assistant.

The water-based anti-falling paint is prepared from the following raw materials in percentage by weight: 30% of polyvinyl butyral, 0.6% of talcum powder, 0.16% of polyethylene wax, 60.9% of ethanol, 8% of water and 0.34% of auxiliary agent. The aqueous anti-drop coating adopts polyvinyl butyral which is a resin material with high transparency and strong adhesive force, can prevent a printing color layer from being decolored when used for gravure, and simultaneously, polyethylene wax is added as a carrier of the pigment, so that the wear resistance of the ink is improved, the dispersibility and the anti-settling effect of the pigment and the filler are improved, and a printed product has good luster, transparency and stereoscopic impression.

The invention also provides a preparation method of the light permeable loose paper, which comprises the following steps:

a. 2 groups of water-based transparent colorful ink layers are printed on the Chinese cypress raw paper layer 1 by adopting a gravure printing process, the printing pressure is 3-6bar, and the printing speed is 120-150 m/min; the solid content of the water-based transparent colorful ink layer is 20-30%, the viscosity (Chai cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

b. After printing all the water-based transparent colorful ink layers 2, printing a layer of water-based anti-dropping coating 3 to prevent the color layers from being decolored and keep the color and the glossiness of the color layers; the solid content of the water-based anti-falling coating 3 is 5-10%, the viscosity (Chaishi cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

c. And printing a high gloss oil layer 4 on the surface of the water-based anti-release coating 3 to increase the brightness of the color layer, wherein the number of gravure rollers is 80L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

d. Drying: the drying temperature of the drying tunnel is respectively 150 +/-10 ℃ to 140 +/-5 ℃ to 150 +/-10 ℃.

e. After the front side is printed and rolled, a single-color alcohol ink layer 5 is printed on the back side by using a pattern and a character printing plate through a single-color gravure, wherein the alcohol ink contains a titanium dioxide component and a calcium carbonate component, and has high coverage rate and low transparency; the solid content of the alcoholic ink is 20-30%, and the viscosity (Chaishi cup (immersion type) 3#, 25 ℃) is 25-30 s; the number of gravure roller lines was 70L/cm. The single-color alcohol ink layer 5 has the pattern and characters in hidden design, the inner printing plate making process is completely the same as the surface printing plate making process, but the image on the printing plate is reverse image during the surface printing plate making process, the printed image is positive image, the inner printing plate text is positive image, and the printed image is reverse image. The printed characters and patterns are gravure printed by the single-color low-viscosity alcohol ink, the smoothness of the back of the paper is low, the printed characters and patterns are light and fuzzy, and the hidden characters and patterns ensure that the back is not displayed under the condition of no bright light irradiation and cannot be seen by naked eyes from the front, so that the aim of anti-counterfeiting printing is fulfilled. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

Example 4: the light permeable loose paper is formed by sequentially arranging a ground color water-based transparent color ink layer 2, a water-based anti-dropping coating layer 3 and a high gloss oil layer 4 on the front side of a raw paper layer 1 of the pine and a single color alcohol ink layer 5 on the back side.

The tipping base paper layer 1 is quantitatively 36-40 g/m²The front smoothness is 7000-8000S, the back smoothness is 100-200S, the coating is uniform, the reflective strength is high, the anti-counterfeiting laser material is particularly strong in effect, strong in metal texture, high in transparency, and high in glossiness and folding resistance.

The water-based transparent colorful ink layer 2, the water-based anti-dropping coating 3 and the high gloss oil layer 4 are sequentially arranged on the front surface of the tipping raw paper layer 1 in a full-page superposition manner.

The single-color alcoholic ink layer 5 is characters or patterns for marking anti-counterfeiting information, the characters or patterns are arranged on the reverse side of the Chinese cypress raw paper layer 1 at intervals of 3-8 mm in a mirror mode, and each pattern or character is 3-10 mm long and 3-10 mm wide.

Preferably, the aqueous transparent color ink layer 2 is provided as 1 layer.

The water-based transparent color ink does not contain titanium dioxide and calcium carbonate, has low covering rate and high ink transparency; the material is prepared from the following raw materials in percentage by weight: 10% of pigment red, 55% of acrylate copolymer, 2.7% of silicon dioxide, 22% of ethanol, 10% of water and 0.3% of auxiliary agent. The water-based transparent ink colorant is completely or mostly made of high-grade transparent pigment, the connecting material is made of high-grade transparent resin as a main raw material and other various auxiliary agents through fine grinding, and the water-based transparent ink has very low covering power and extremely high transparency. The fineness of the transparent ink is finely ground to be less than 10 microns, so that the covering power and the transferability of the transparent ink are good, and the transparent ink has the characteristics of high viscosity, high transparency, high brightness, good leveling property, bright color, firm adhesion, strong tinting strength and the like. It is especially suitable for printing raw tipping paper with plain medium, which has high smoothness and transparency, and the transparency of the transparent ink is determined by pigment, binder and assistant.

The water-based anti-falling paint is prepared from the following raw materials in percentage by weight: 22.9 percent of polyvinyl butyral, 0.9 percent of talcum powder, 0.07 percent of polyethylene wax, 72 percent of ethanol, 4 percent of water and 0.13 percent of auxiliary agent. The aqueous anti-drop coating adopts polyvinyl butyral which is a resin material with high transparency and strong adhesive force, can prevent a printing color layer from being decolored when used for gravure, and simultaneously, polyethylene wax is added as a carrier of the pigment, so that the wear resistance of the ink is improved, the dispersibility and the anti-settling effect of the pigment and the filler are improved, and a printed product has good luster, transparency and stereoscopic impression.

The invention also provides a preparation method of the light permeable loose paper, the method adopts an online one-step completion front and back printing, and the front side is printed with multicolor and then the back side is printed in a reverse way, and the method comprises the following steps:

a. printing a water-based transparent color ink layer 2 on a tipping raw paper layer 1 by adopting a gravure printing process, wherein the printing pressure is 3-6bar, and the printing speed is 120-150 m/min; the solid content of the water-based transparent colorful ink layer is 20-30%, the viscosity (Chai cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

b. After printing all the water-based transparent colorful ink layers 2, printing a layer of water-based anti-dropping coating 3 to prevent the color layers from being decolored and keep the color and the glossiness of the color layers; the solid content of the water-based anti-falling coating 3 is 5-10%, the viscosity (Chaishi cup (immersion type) 2#, 25 ℃) is 20-25 s, and the number of gravure roller lines is 100L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

c. And printing a high gloss oil layer 4 on the surface of the water-based anti-release coating 3 to increase the brightness of the color layer, wherein the number of gravure rollers is 80L/cm. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform.

d. After the front side is printed and rolled, a monochromatic alcohol ink layer 5 is printed on the back side by a printing machine reverse rotation function and a monochromatic intaglio printing plate by using patterns and character printing plates, wherein the alcohol ink contains a titanium dioxide component and a calcium carbonate component, and has high coverage rate and low transparency; the solid content of the alcoholic ink is 20-30%, and the viscosity (Chaishi cup (immersion type) 3#, 25 ℃) is 25-30 s; the number of gravure roller lines was 70L/cm. The single-color alcohol ink layer 5 has the pattern and characters in hidden design, the inner printing plate making process is completely the same as the surface printing plate making process, but the image on the printing plate is reverse image during the surface printing plate making process, the printed image is positive image, the inner printing plate text is positive image, and the printed image is reverse image. The printed characters and patterns are gravure printed by the single-color low-viscosity alcohol ink, the smoothness of the back of the paper is low, the printed characters and patterns are light and fuzzy, and the hidden characters and patterns ensure that the back is not displayed under the condition of no bright light irradiation and cannot be seen by naked eyes from the front, so that the aim of anti-counterfeiting printing is fulfilled. And meanwhile, the pattern is printed by using the electrostatic ink absorption device, and the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear and the ink layer is uniform. Meanwhile, the pattern is printed by using the electrostatic ink absorption device, the electrostatic ink absorption can increase the adhesive force of the ink, so that the pattern is clear, and the ink layer is uniform; the front and back printing is completed simultaneously.

e. Drying: the drying tunnel of the printing machine is a double drying tunnel and a long drying tunnel, and the drying temperature of the drying tunnel is respectively 100 +/-10 ℃ to 90 +/-10 ℃ to 100 +/-10 ℃.