阅读说明：本技术 一种未涂布的数码纸及其制备方法 (Uncoated digital paper and preparation method thereof ) 是由 李情兰 许正茂 韦克 于 2020-12-04 设计创作，主要内容包括：本发明涉及一种未涂布的数码纸及其制备方法,属于造纸技术领域。本发明使用湿部化学品、表面化学品及剥离剂对纸张进行处理,使纸张表面细腻、墨水喷到纸表面能快速与纸页结合而且不扩散,迅速锁定墨水,即使遇水也不容易扩散开,达到改善数码喷墨印刷的印刷质量和色彩稳定性的效果。本发明未涂布的数码纸,可以丰富产品结构,提升产品形象；本发明数码纸的研发紧密结合目前数码技术和印刷行业的发展,把握市场发展方向,能够适应各种印刷要求,市场前景广阔。(The invention relates to uncoated digital paper and a preparation method thereof, belonging to the technical field of papermaking. The paper is treated by the wet end chemicals, the surface chemicals and the stripping agent, so that the surface of the paper is fine and smooth, the ink is sprayed on the surface of the paper and can be quickly combined with the paper sheet without diffusion, the ink is quickly locked and cannot be easily diffused even when meeting water, and the effects of improving the printing quality and the color stability of the digital ink-jet printing are achieved. The uncoated digital paper can enrich the product structure and improve the product image; the research and development of the digital paper of the invention are closely combined with the development of the present digital technology and printing industry, the market development direction is grasped, various printing requirements can be adapted, and the market prospect is wide.)

1. A preparation method of uncoated digital paper comprises the steps of pulp disintegration and slag discharge, pulping, pulp preparation, sizing, wire feeding, squeezing and dewatering, paper sheet pre-drying, paper sheet surface treatment, paper sheet post-drying, paper sheet hard press polishing treatment and paper sheet coiling, and is characterized in that wet-end chemicals used in the steps comprise the following components in amount: 100kg of calcium carbonate per ton of paper, 5-10kg of alkyl ketene dimer per ton of paper, 2-3kg of silica gel per ton of paper, 0.15-0.4kg of polyacrylamide per ton of paper, 0.15-0.4kg of amphoteric polyacrylamide particles per ton of paper, 0.1-0.5kg of pulping enzyme per ton of paper, 0.2-0.4kg of defoaming agent per ton of paper, 0.2-1.5kg of bactericide per ton of paper, 0.2-0.5kg of fixing agent per ton of paper and 1-3kg of wrapping agent per ton of paper;

the surface chemistry used in the above process comprises the following components in amounts: 25-60kg of native starch per ton of paper, 0.02-0.1kg of amylase per ton of paper, 8-10kg of calcium chloride per ton of paper, 5-15kg of cationic polymer color stabilizer per ton of paper and 1-5kg of nano-silicon dioxide per ton of paper;

0.1-0.3 kg/ton paper of release agent is also used in the above process.

2. The method of claim 1, wherein the wet end chemical comprises the following ingredients in amounts: 150 kg of calcium carbonate per ton of paper, 6-7kg of alkyl ketene dimer per ton of paper, 2.5kg of silica gel per ton of paper, 0.2-0.3kg of polyacrylamide per ton of paper and 0.2-0.3kg of amphoteric polyacrylamide particles per ton of paper.

3. The method of claim 1, wherein the surface chemistry comprises the following components in amounts: 30-40kg of native starch per ton of paper, 0.02-0.1kg of amylase per ton of paper, 10kg of calcium chloride per ton of paper, 8-10kg of cationic polymer color stabilizer per ton of paper and 5kg of nano-silicon dioxide per ton of paper.

4. The method of claim 1, wherein the pulp is 100% whole wood pulp, the calcium carbonate comprises heavy calcium carbonate and light calcium carbonate, the pulping enzyme is at least one of cellulase, hemicellulase and xylanase, the antifoaming agent is a high fatty alcohol antifoaming agent, the bactericide is obtained by reacting ammonium sulfate with a bleaching solution, and the bleaching solution is sodium hypochlorite; the fixing agent is a cationic low-molecular-weight polyamine substance, the wrapping agent comprises a wrapping agent 1 and a wrapping agent 2, the wrapping agent 1 is a polyacrylamide grafted functional group monomer, the wrapping agent 2 is anionic high-molecular-weight starch and chitosan, the stripping agent is a polyamide stripping agent or a mineral oil stripping agent, and the cationic high-molecular-weight color stabilizer is a polyamine condensation polymer.

5. The method according to claim 1, wherein the pulp is disintegrated and discharged by disintegrating long-fiber and short-fiber kraft pulps at a concentration of 5%, pulping enzymes are added during the disintegration, the pulp is treated with a high consistency discharger at a mass concentration of 4%, and then fixing agents are added.

6. The production method according to claim 1, wherein the beating process is beating of the disintegrated slurry at a concentration of 4%; the slurry preparation process is to prepare slurry in proportion, and after the slurry preparation is finished, the light calcium carbonate treated by the wrapping agent is added; adding the heavy calcium carbonate treated by the wrapping agent, then adding silica gel, polyacrylamide and amphoteric polyacrylamide particles, and adding the bactericide into a white water system and a broke system; the net feeding process includes feeding pulp of concentration 1.0-1.5% to net via pulp flowing box, forming roller, loading unit, vacuum chamber and high vacuum box to dewater, and the paper sheet has dryness of 15-25%.

7. The method of claim 1, wherein the sheet dryness of the two shoe press in the press dewatering process is 47-55%; in the paper sheet pre-drying process, the dryness of a paper sheet dried by a single-row drying cylinder is 90-97%, and a stripping agent is added on the surface of a first drying cylinder; in the paper sheet surface treatment process, a metering sizing technology is adopted to carry out surface treatment on paper sheets, an enzyme conversion technology is used to cook raw starch, and then a cationic polymer color stabilizer, calcium chloride, nano-scale silicon dioxide and a defoaming agent are added.

8. The process according to claim 1, wherein the sheet is hard calendered by a crown roll with a loading pressure of 20-100 KN/m.

9. The method according to claim 6, wherein the light calcium carbonate has a particle size of 10 to 15um, and the heavy calcium carbonate has a particle size of 15 um.

10. An uncoated digital paper prepared by the method of any one of claims 1 to 9.

Technical Field

The invention relates to uncoated digital paper and a preparation method thereof, belonging to the technical field of papermaking.

Background

The existing printing modes mainly comprise offset printing, carbon powder digital printing, ink-jet digital printing and electronic ink digital printing. The offset printing quality is good, and the offset printing method is the mainstream publishing printing mode at present; however, it requires plate making, invariable information printing, is less flexible, and when the print volume is low, the cost of a single sheet is high. The carbon powder digital printing quality is good, and the information printing can be changed; but the speed is slow, the temperature is high, the paper is easy to curl, and the cost is high. The ink-jet digital printing variable information printing has low cost and acceptable printing quality by using the original ink compared with offset printing and carbon powder digital printing; however, the printing quality is still to be improved, and it is difficult to replace offset printing in a short period of time, and the demand for paper is high. The electronic ink digital printing variable information printing has better printing quality; however, the printing machine, the electronic ink and the electronic paint are required to be used simultaneously, and the paper processing cost is high.

The digital ink jet printing technology has the characteristic of low cost, but has difficulty in popularization due to poor quality after printing. At present, the digital paper is coated in a trace amount on the market, namely, a certain amount of special sizing material is coated on the base paper through a surface sizing technology, so that the absorptivity and the color stability of ink are improved, and the printing quality is improved.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide uncoated digital paper and a preparation method thereof, and the preparation method can improve the quality of the uncoated paper digital ink jet printing.

In order to achieve the purpose, the invention adopts the technical scheme that: a preparation method of uncoated digital paper comprises the steps of pulp disintegration and slag discharge, pulping, pulp preparation, sizing, net surfing, squeezing and dewatering, paper sheet pre-drying, paper sheet surface treatment, paper sheet post-drying, paper sheet hard press polishing treatment and paper sheet coiling,

the wet end chemicals used in the above steps include the following ingredients in amounts: 100kg of calcium carbonate, 400kg of calcium carbonate per ton of paper, 5-10kg of alkyl ketene dimer per ton of paper (added in a pulp preparation working section), 2-3kg of silica gel per ton of paper (added in a pulp preparation working section), 0.15-0.4kg of polyacrylamide per ton of paper (added in a pulp preparation working section), 0.15-0.4kg of amphoteric polyacrylamide particles per ton of paper (added in a pulp preparation working section), 0.1-0.5kg of pulping enzyme per ton of paper (added in a pulping working section), 0.2-0.4kg of defoaming agent per ton of paper (added in a pulp preparation working section), 0.2-1.5kg of bactericide per ton of paper, 0.2-0.5kg of fixing agent per ton of paper (added in a working section before pulp preparation), and 1-3kg of wrapping agent per ton of paper (added in a filler); the coating agent comprises a coating agent 1 and a coating agent 2;

the surface chemistry used in the above process comprises the following components in amounts: 25-60kg of native starch per ton of paper, 0.02-0.1kg of amylase per ton of paper, 8-10kg of calcium chloride per ton of paper, 5-15kg of cationic polymer color stabilizer per ton of paper and 1-5kg of nano-silicon dioxide per ton of paper;

0.1-0.3 kg/ton paper of release agent is also used in the above process.

In the wet end chemicals, the silica gel is matched with polyacrylamide and particles, so that the cleanness of a paper machine system can be better kept, and paper is white and free of impurities; the fixing agent can effectively control the anionic trash of the system, and lays a good foundation for adding cationic chemicals on the surface of paper; the use of 2 kinds of wrapping agents is realized, the wrapping agent 1 is a polyacrylamide grafted functional group monomer and is of a net structure, heavy calcium carbonate and light calcium carbonate are respectively treated, the particle size of the heavy calcium carbonate is increased to 10-15um from about 2um, and the particle size of the light calcium carbonate is increased to about 15um from about 3um, so that the filler forms a globular shape; the wrapping agent 2 is mainly prepared from anionic high molecular starch and chitosan, is an anionic linear high molecular substance, can fix the small balls of the filler, and improves the stability of the filler balls. After the filler is treated by the method, the stability of the filler in paper is better, the paper powder amount in the using process can be reduced, and the bulk of the paper can be improved.

The invention controls the water absorption value of paper to be 40-100gsm by adding a small amount of alkyl ketene dimer, so that the paper has good water absorption and can quickly absorb ink during printing; the surface of the drying cylinder is provided with the stripping agent, so that the paper is not easy to adhere to the drying cylinder in the drying process, and the surface of the paper is clean and has no paper powder and paper hair; the cationic polymer color stabilizer, calcium chloride and silicon dioxide are arranged in native starch according to a certain proportion, the chemicals are applied to the surface of paper, the polymer color stabilizer is a polymer cationic substance, has a strong locking effect on anionic ink, and enables the ink to keep high stability on the surface of the paper by the polymer substance, so that a double locking effect is achieved; the calcium chloride can effectively eliminate static electricity and has strong water absorption performance, and during the ink-jet printing process of paper, the calcium chloride can quickly lock ink to avoid ink diffusion, and the function of locking the ink is added; the silicon dioxide is a very fine surface treating agent, and because the particle size is small, the surface of the paper can be smooth and flat when the silicon dioxide is coated on the surface of the paper, the absorption effect of ink can be effectively improved, and the color effect of the paper can be well improved in the printing process. The chemicals are mixed according to a certain proportion to meet different requirements of digital paper.

As a preferred embodiment of the preparation method of the present invention, the wet end chemical comprises the following components in amounts: 150 kg of calcium carbonate per ton of paper, 6-7kg of alkyl ketene dimer per ton of paper, 2.5kg of silica gel per ton of paper, 0.2-0.3kg of polyacrylamide per ton of paper and 0.2-0.3kg of amphoteric polyacrylamide particles per ton of paper.

As a preferred embodiment of the preparation method according to the invention, the surface chemistry comprises the following components in amounts: 30-40kg of native starch per ton of paper, 0.02-0.1kg of amylase per ton of paper, 10kg of calcium chloride per ton of paper, 8-10kg of cationic polymer color stabilizer per ton of paper and 5kg of nano-silicon dioxide per ton of paper.

As a preferable embodiment of the preparation method of the present invention, the slurry is 100% whole wood pulp, the calcium carbonate is heavy calcium carbonate and light calcium carbonate, the pulping enzyme is at least one of cellulase, hemicellulase and xylanase, the antifoaming agent is a high fatty alcohol antifoaming agent, the bactericide is obtained by reacting ammonium sulfate and bleaching solution (sodium hypochlorite), the fixing agent is a cationic low molecular weight polyamine substance, the wrapping agent comprises a wrapping agent 1 and a wrapping agent 2, the wrapping agent 1 is a polyacrylamide grafted functional group monomer, the wrapping agent 2 is anionic high molecular weight starch and chitosan, the stripping agent is a polyamide stripping agent or a mineral oil stripping agent, and the cationic high molecular weight color stabilizer is a polyamine polycondensate.

Preferably, the bactericide is ammonium sulfate and a bleaching solution which react in a reactor to generate monovalent ammonium chloride for microbial control sterilization; the fixing agent is an interfering substance for eliminating anions, and the method of charge neutralization, adsorption or agglomeration is adopted to eliminate or reduce the anion interfering substance of the paper machine system; the coating agent 1 is a polyacrylamide grafted functional group monomer, heavy calcium carbonate and light calcium carbonate are respectively treated, the particle size of the heavy calcium carbonate is increased from about 2um to 10-15um, and the particle size of the light calcium carbonate is increased from about 3um to about 15um, so that the filler forms a globular shape; the wrapping agent 2 is mainly prepared from anionic high molecular starch and chitosan, is an anionic linear high molecular substance, can fix the small balls of the filler, and improves the stability of the filler balls. After the filler is treated by the method, the stability of the filler in paper is better, the paper powder amount in the using process can be reduced, and the bulk of the paper can be improved.

As a preferred embodiment of the preparation method, the pulp disintegrating and deslagging process comprises the steps of disintegrating long-fiber sulfate wood pulp and short-fiber sulfate wood pulp according to the concentration of 5%, adding a pulping enzyme in the pulp disintegrating process to ensure that the pulping enzyme has enough contact time with fibers, treating the pulp through a high-concentration slag remover at the concentration of 4%, and then adding a fixing agent into the BCTMP pulp.

Preferably, the long fiber sulfate wood pulp is imported canadian horse bleached softwood pulp, imported canadian dolphin brand bleached softwood pulp, or imported chile silver star bleached softwood pulp; the short fiber sulfate wood pulp is Indonesia lobular Acacia wood pulp, Shandong sunshine Asia Taisen Bolei wood pulp, Shandong sunshine Asia Taisen Bo pure eucalyptus pulp or Shandong sunshine Asian Bosen Bo mixed eucalyptus pulp; the chemi-mechanical pulp is the chemi-mechanical pulp of Tianbai, Crystal or cavalier.

As a preferred embodiment of the preparation method, the pulping process is to pulp the disintegrated pulp at a concentration of 4%, and under the chemical action of pulping enzyme and the mechanical action of grinding discs, the effect of optimizing fiber devillicate brooming is achieved; the slurry preparation process is to prepare slurry in proportion, and after the slurry preparation is finished, the light calcium carbonate treated by the wrapping agent is added; adding the heavy calcium carbonate treated by the wrapping agent, then adding silica gel, polyacrylamide and amphoteric polyacrylamide particles, and adding the bactericide into a white water system and a broke system; the net feeding process includes feeding pulp of concentration 1.0-1.5% to net via pulp flowing box, forming roller, loading unit, vacuum chamber and high vacuum box to dewater, and the paper sheet has dryness of 15-25%.

As a preferred embodiment of the preparation method, the dryness of the paper sheet after two shoe pressing in the press dewatering process is 47-55%; in the paper sheet pre-drying process, the dryness of a paper sheet dried by a single-row drying cylinder is 90-97%, and a stripping agent is added on the surface of a first drying cylinder, so that the paper sheet is easy to adhere to the drying cylinder in the drying process, and the surface of the paper sheet is clean and has no paper powder and paper wool; in the paper sheet surface treatment process, a metering sizing technology is adopted to carry out surface treatment on paper sheets, an enzyme conversion technology is used to cook raw starch, and then a cationic polymer color stabilizer, calcium chloride, nano-scale silicon dioxide and a defoaming agent are added.

As a preferred embodiment of the preparation method of the present invention, the sheet post-drying process is to remove moisture from the surface-treated sheet by post-drying.

As a preferred embodiment of the preparation method, in the paper sheet hard calendering treatment process, a paper sheet is subjected to hard calendering treatment by using a controllable medium-high roller, the hard calendering loading pressure is 20-100KN/m, and the two-side difference of the roughness (or smoothness) of the paper sheet can be reduced by using a hard calendering technology.

As a preferable embodiment of the preparation method of the present invention, the light calcium carbonate has a particle size of 10 to 15um, and the heavy calcium carbonate has a particle size of 15 um.

In a second aspect, the present invention provides an uncoated digital paper prepared by the above preparation method.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention uses the chemicals to process paper, so that the surface of the paper is fine and smooth, the ink sprayed on the surface of the paper can be quickly combined with the paper sheet without diffusion, the ink is quickly locked, the ink is not easy to diffuse even if meeting water, and the effects of improving the printing quality and the color stability of digital ink-jet printing are achieved.

(2) The uncoated digital paper can enrich the product structure and improve the product image; the research and development of the digital paper are closely combined with the development of the current digital technology and printing industry, the market development direction is mastered, various printing requirements can be met, and the market prospect is wide.

Drawings

FIG. 1 is a flow chart of a method of making uncoated digital paper according to the present invention.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the following detailed description of the preferred embodiments.

The flow chart of the preparation method of the uncoated digital paper of the invention is shown in figure 1.

Example 1

A preparation method of uncoated digital paper comprises the processes of pulp disintegration and slag discharge, pulping, pulp preparation, sizing, net surfing, squeezing and dehydration, paper sheet pre-drying, paper sheet surface treatment, paper sheet post-drying, paper sheet hard calendaring treatment and paper sheet coiling,

the wet end chemicals used in the above process comprise the following components in amounts: 400kg of calcium carbonate per ton of paper, 5kg of alkyl ketene dimer per ton of paper (added in a pulp preparation working section), 2kg of silica gel per ton of paper, 0.15kg of polyacrylamide per ton of paper, 0.4kg of amphoteric polyacrylamide particles per ton of paper, 0.1kg of pulping enzyme per ton of paper, 0.2kg of defoaming agent per ton of paper, 0.2kg of bactericide per ton of paper, 0.5kg of fixing agent per ton of paper and 3kg of wrapping agent per ton of paper;

the surface chemistry used in the above process comprises the following components in amounts: 25kg of native starch per ton of paper, 0.02kg of amylase per ton of paper, 10kg of calcium chloride per ton of paper, 5kg of cationic polymer color stabilizer per ton of paper and 1kg of nano-silicon dioxide per ton of paper;

0.1 kg/ton of paper release agent is also used in the process;

the slurry is 100% whole wood pulp, the calcium carbonate is ground limestone and light calcium carbonate, the pulping enzyme is the cellulase, the defoaming agent is high fatty alcohol defoaming agent, the germicide is obtained by the reaction of ammonium sulfate and bleaching solution (sodium hypochlorite), the fixative is cation low molecular weight polyamine substance, the wrapping agent is polyacrylamide grafted functional group monomer, wrapping agent 1 is polyacrylamide grafted functional group monomer, wrapping agent 2 is anion high molecular starch and chitosan, the stripping agent is polyamide stripper or mineral oil stripper, cation polymer color stabilizer is polyamine condensation polymer.

The pulp disintegrating and deslagging process is to disintegrate long-fiber sulfate wood pulp and short-fiber sulfate wood pulp according to the concentration of 5%, pulping enzyme is added in the pulping process to ensure that the pulping enzyme and fibers have enough contact time, the pulp is treated by a high-concentration deslagging device under the concentration of 4%, and then a fixing agent is added into the BCTMP pulp;

the pulping process is characterized in that the pulp after being crushed is pulped at the concentration of 4 percent, and the effect of optimizing fiber fibrillation is achieved under the chemical action of pulping enzyme and the mechanical action of a grinding disc; the slurry preparation process is to prepare slurry in proportion, and after the slurry preparation is finished, the light calcium carbonate treated by the wrapping agent is added; adding the heavy calcium carbonate treated by the wrapping agent, then adding silica gel, polyacrylamide and amphoteric polyacrylamide particles, and adding the bactericide into a white water system and a broke system; the net feeding process comprises the steps of feeding pulp with the concentration of 1.0-1.5% onto a net through a pulp flowing box, dehydrating through a forming roll, a loading unit, a vacuum chamber and a high vacuum box, and controlling the dryness of paper sheets to be 15-25% after dehydration;

the dryness of the paper sheet after the two-stage shoe pressing in the pressing and dewatering process is 47-55%; in the paper sheet pre-drying process, the dryness of a paper sheet dried by a single-row drying cylinder is 90-97%, and a stripping agent is added on the surface of a first drying cylinder, so that the paper sheet is easy to adhere to the drying cylinder in the drying process, and the surface of the paper sheet is clean and has no paper powder and paper wool; in the paper sheet surface treatment process, a metering sizing technology is adopted to carry out surface treatment on paper sheets, an enzyme conversion technology is used to cook raw starch, and then a cationic polymer color stabilizer, calcium chloride, nano-scale silicon dioxide and a defoaming agent are added;

the post-drying process of the paper sheet is to remove the water in the paper sheet after surface treatment through post-drying; in the paper sheet hard calendering processing technology, a paper sheet is subjected to hard calendering processing by adopting a controllable medium-high roller, the hard calendering loading pressure is 20-100KN/m, and the two-side difference of the roughness (or smoothness) of the paper sheet can be reduced by adopting a hard calendering technology.

Example 2

A preparation method of uncoated digital paper comprises the processes of pulp disintegration and slag discharge, pulping, pulp preparation, sizing, net surfing, squeezing and dehydration, paper sheet pre-drying, paper sheet surface treatment, paper sheet post-drying, paper sheet hard calendaring treatment and paper sheet coiling,

the wet end chemicals used in the above process comprise the following components in amounts: 100kg of calcium carbonate per ton of paper, 10kg of alkyl ketene dimer per ton of paper, 3kg of silica gel per ton of paper, 0.4kg of polyacrylamide per ton of paper, 0.15kg of amphoteric polyacrylamide particles per ton of paper, 0.5kg of pulping enzyme per ton of paper, 0.4kg of defoaming agent per ton of paper, 1.5kg of bactericide per ton of paper, 0.2kg of fixing agent per ton of paper and 1kg of wrapping agent per ton of paper;

the surface chemistry used in the above process comprises the following components in amounts: 60kg of native starch per ton of paper, 0.1kg of amylase per ton of paper, 8kg of calcium chloride per ton of paper, 15kg of cationic polymer color stabilizer per ton of paper and 5kg of nano-silicon dioxide per ton of paper;

0.3 kg/ton of paper release agent is also used in the process;

the slurry is 100% of whole wood pulp, the calcium carbonate is heavy calcium carbonate and light calcium carbonate, the pulping enzyme is hemicellulase, the defoaming agent is a high-fatty alcohol defoaming agent, the bactericide is obtained by reacting ammonium sulfate with bleaching liquid (sodium hypochlorite), the fixing agent is a cationic low-molecular-weight polyamine substance, the wrapping agent is a polyacrylamide grafted functional group monomer, the wrapping agent 1 is a polyacrylamide grafted functional group monomer, the wrapping agent 2 is anionic high-molecular starch and chitosan, the stripping agent is a polyamide stripping agent or a mineral oil stripping agent, and the cationic high-molecular color stabilizer is a polyamine polycondensate;

the process steps are the same as in example 1.

Example 3

A preparation method of uncoated digital paper comprises the processes of pulp disintegration and slag discharge, pulping, pulp preparation, sizing, net surfing, squeezing and dehydration, paper sheet pre-drying, paper sheet surface treatment, paper sheet post-drying, paper sheet hard calendaring treatment and paper sheet coiling,

the wet end chemicals used in the above process comprise the following components in amounts: 300kg of calcium carbonate per ton of paper, 7kg of alkyl ketene dimer per ton of paper, 2.5kg of silica gel per ton of paper, 0.3kg of polyacrylamide per ton of paper, 0.3kg of amphoteric polyacrylamide particles per ton of paper, 0.2kg of pulping enzyme per ton of paper, 0.3kg of defoaming agent per ton of paper, 1.0kg of bactericide per ton of paper, 0.3kg of fixing agent per ton of paper and 2kg of wrapping agent per ton of paper;

the surface chemistry used in the above process comprises the following components in amounts: 40kg of native starch per ton of paper, 0.05kg of amylase per ton of paper, 9kg of calcium chloride per ton of paper, 10kg of cationic polymer color stabilizer per ton of paper and 3kg of nano-silicon dioxide per ton of paper;

0.2 kg/ton of paper release agent is also used in the process;

the slurry is 100% of whole wood pulp, the calcium carbonate is heavy calcium carbonate and light calcium carbonate, the pulping enzyme is at least one of cellulase, hemicellulase and xylanase, the defoaming agent is a high-fatty alcohol defoaming agent, the bactericide is obtained by reacting ammonium sulfate with bleaching liquid (sodium hypochlorite), the fixing agent is a cationic low-molecular polyamine substance, the wrapping agent is a polyacrylamide grafted functional group monomer, the wrapping agent 1 is a polyacrylamide grafted functional group monomer, the wrapping agent 2 is anionic high-molecular starch and chitosan, the stripping agent is a polyamide stripping agent or a mineral oil stripping agent, and the cationic high-molecular color stabilizer is a polyamine polycondensate;

the process steps are the same as in example 1.

Effect example 1

The quality of the digital paper prepared in examples 1 to 3 was measured, and the measurement results are shown in table 1.

TABLE 1

As can be seen from Table 1, the digital paper prepared by the preparation method of the invention meets the production index and quality range of 80 g of digital paper.

Effect example 2

In order to investigate the influence of various chemicals on the printing quality and color stability of the digital paper in the preparation method, test groups 1-5, control groups 1-2 and an original formula are set. In the test groups 1 to 5 and the control groups 1 to 2, only the amounts of the chemicals were different, and as shown in table 2 (the amounts of the chemicals were kg/ton of paper), the material selection and the processing steps of the chemicals were the same. Meanwhile, the printing quality and color stability of the prepared digital paper were tested, and the test results are shown in table 3.

Wherein the original formula comprises 300kg of calcium carbonate per ton of paper, 1.1kg of ASA per ton of paper, 2.5kg of bentonite per ton of paper, 0.3kg of polyacrylamide per ton of paper, 0.3kg of amphoteric polyacrylamide particles per ton of paper, 0.3kg of defoaming agent per ton of paper and 1.0kg of bactericide per ton of paper;

the color stability test method comprises the following steps: and (3) evaluating the stability after meeting water, soaking color blocks of the paper of the original formula and the digital paper of the test groups 1-5 and the control groups 1-2 in deionized water for 1 minute after ink-jet printing, then placing the paper in a dark room with constant temperature and humidity for airing, detecting the color density of the color blocks by using a spectrophotometer, and calculating the fading condition of the KCMY color blocks.

The diffusivity test method comprises the following steps: and judging according to the ink dropping area of the ink and the edge roughness of the font.

The method for testing the speed of the ink comprises the following steps: the color chart was printed using the same amount of ink and the density of the ink in the color chart was then measured to evaluate the speed of ink lock, the faster the speed the higher the density of the ink, the percentage increase in the test relative to the original formulation.

TABLE 2

TABLE 3

As can be seen from Table 3, the digital paper prepared by the method of the present invention can be rapidly combined with paper sheets without diffusion, rapidly lock ink, and is not easily diffused even when meeting water, thereby achieving the effects of improving the printing quality and color stability of digital ink-jet printing. In the comparison groups 1-2, the amount of each component is not within the range of the invention, and the performance of the prepared digital paper is not as good as that of the invention. And, when the wet end chemical comprises the following ingredients in amounts: 15-20% of calcium carbonate, 6-7kg of alkyl ketene dimer per ton of paper, 2.5kg of silica gel per ton of paper, 0.2-0.3kg of polyacrylamide per ton of paper and 0.2-0.3kg of amphoteric polyacrylamide particles per ton of paper, wherein the surface chemicals comprise the following components in amount: 30-40kg of native starch per ton of paper, 0.02-0.1kg of amylase per ton of paper, 10kg of calcium chloride per ton of paper, 8-10kg of cationic polymer color stabilizer per ton of paper and 5kg of nano-scale silicon dioxide per ton of paper, and the prepared digital paper has the best printing quality and color stability.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.