CN108221478B

CN108221478B - Soaking type surface sizing process

Info

Publication number: CN108221478B
Application number: CN201810241595.8A
Authority: CN
Inventors: 赵志芳; 顾佳燕
Original assignee: Zhejiang Rongsheng Paper Industry Holding Co ltd
Current assignee: Jiaxing Rongsheng packaging material Co.,Ltd.
Priority date: 2018-03-22
Filing date: 2018-03-22
Publication date: 2020-08-21
Anticipated expiration: 2038-03-22
Also published as: CN108221478A

Abstract

The invention discloses a soaking type surface sizing process, which belongs to the technical field of paper product sizing, and has the technical key points that the sizing agent is uniformly dispersed, steamed and lifted to spray, the upper and lower rubber rollers are used for extrusion and gluing, the sizing agent overflows and reflows, then the sizing agent is subjected to impurity removal treatment by a vibrating screen and then flows back to a dispersion tank, and the operation of sizing the paper product can be completed by circulating and reciprocating in sequence. The sizing process can effectively reduce the occurrence of paper breakage and improve the production efficiency of paper by controlling the viscosity and concentration of starch and the diameters and buckling widths of the upper and lower rubber rollers; in addition, the hard rubber sleeve and the soft rubber sleeve are arranged, so that the glue leakage phenomenon of the upper and lower rubber rollers is reduced, the probability of paper breaking is further reduced, and the paper production efficiency is improved.

Description

Soaking type surface sizing process

Technical Field

The invention belongs to the technical field of paper product sizing, and particularly relates to a soaking type surface sizing process.

Background

Paper pulp (raw material) is molded by 1 and screen cloth: the paper pulp and other additives are slowly formed into paper on the mesh; 2. squeezing: applying certain pressure on the mesh cloth and the formed paper, and allowing excess water to flow out from the lower part of the mesh cloth to obtain paper with the dryness of 48%; 3. pre-drying (i.e. first drying treatment): transmitting the paper into a dryer through a transmission device, and introducing 120-180 ℃ steam into the oven to improve the stability of the oven, so as to obtain the paper with the dryness of 92-93%; 4. sizing: continuously transmitting the dried paper into a glue applying device, and after glue is sprayed by a glue applying pipe, enabling a sizing agent to be uniformly coated on the front side and the back side of the paper under the extrusion action of an upper rubber roll and a lower rubber roll so as to finish glue spraying operation; 5. post-baking: drying the water increased by sizing in the paper to obtain the paper with the dryness of 92-93 percent; 6. coiling: winding the dried paper; 7. rewinding: and the operation process of rolling the rolled paper again after cutting off the paper corners and cutting the paper into a plurality of pieces of paper with specific lengths. Thus, the finished paper can be prepared after the seven steps of operation.

The surface sizing machine is one of important equipment of a paper machine, the physical indexes, the surface water resistance, the paper surface strength and the fineness of paper can be improved through the equipment, the traditional surface sizing mostly adopts horizontal sizing squeezing, namely two rollers which are horizontally arranged are pressed together, glue solution forms a glue solution wedge-shaped glue pool above a press area, paper passes through the glue pool, the glue solution is continuously, uniformly and stably soaked and permeated, the two sides of the paper are squeezed by the glue roller to adsorb certain glue solution, and a very thin film layer is formed on the surface of the finished paper. But the disadvantage is that the vehicle speed is limited, and the liquid level at the glue solution pool is too low, which can reduce the temperature of the glue solution and increase the foam.

At present, most of the existing sizing processes are surface sizing processes, and better ring crush strength can be obtained when high gram weight paper (such as corrugated paper with the weight of more than 100 g) is produced. However, with the economic development, the demand of low-gram-weight paper is increasing day by day, and when the equipment is used for producing low-gram-weight paper (such as 85g corrugated paper), paper breakage is easy to occur, and the production efficiency is low. Therefore, a new technical solution is needed to solve the above problems.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a soaking type surface sizing process which can effectively reduce the occurrence of paper breaking and improve the production efficiency of paper.

In order to achieve the purpose, the invention provides the following technical scheme: a soaking type surface sizing process comprises the following operation steps,

step S1, preparation of sizing agent: the sizing agent comprises edible starch, amylase and water, wherein the concentration of the edible starch is 4-6%, and the viscosity of the edible starch is 20-25%;

step a, putting edible starch and water in proportion and the sizing agent after screening treatment into a dispersion tank and uniformly stirring;

b, heating water to 93-95 ℃, adding the water into a cooking barrel, starting a stirrer, then putting the edible starch and the amylase in the dispersion tank into the cooking barrel, uniformly stirring, stirring for 30-45min, heating to 95 ℃, preserving heat, and cooking for 1h to obtain a sizing agent;

c, adding the propyl benzene sizing agent, the aluminum sulfate and the defoaming agent into the sizing agent in the cooking barrel while stirring, stirring for 20-25min, cooling to 80-90 ℃, and transferring to a sizing barrel for heat preservation and storage;

step S2, conveying the paper dried to 92% dryness into a sizing device through a conveying roller, conveying the sizing agent obtained in the step c into a sizing pipe through a lifting pump, and spraying the sizing agent between an upper rubber roller and a lower rubber roller through a spray head; then the paper passes through the gap between the upper rubber roller and the lower rubber roller, and the sizing agent is uniformly coated on the front side and the back side of the paper under the mutual extrusion of the upper rubber roller and the lower rubber roller;

and step S3, guiding the paper sheet after sizing in the step S2 out of the sizing device through a guide roller.

By adopting the technical scheme, the sizing agent after the edible starch and the amylase are configured and the sizing agent after the screening treatment are uniformly dispersed, so that the raw materials are saved, and the reuse ratio of the sizing agent is improved. Then adding hot water, stirring and configuring, then discharging the sizing agent into a sizing barrel for temporary storage, simultaneously lifting the sizing agent into a sizing roller by adopting a lifting pump, and spraying a part of the sizing agent on two sides of paper by a spray head; and the other part of the sizing agent reflows to the dispersing tank again for reuse, so that the reuse rate of the sizing agent is improved. Subsequently, the paper is through the squeezing action of upper and lower pinch rolls, makes the thin sizing agent of one deck even coating in the positive and negative both sides of paper, controls the concentration and the viscosity of starch simultaneously for moisture content on the paper after the sizing treatment reduces, has promoted the dryness factor of paper (the unit divides starch volume equally promptly and has correspondingly reduced), has optimized the sizing volume of paper from this, can also effectively reduce the emergence of disconnected paper phenomenon simultaneously, has further improved the production efficiency of paper.

The invention is further configured to: in step S2, the surplus sizing agent between the upper and lower rubber rollers flows into the recycling bin from both sides of the upper and lower rubber rollers, and flows into the vibrating screen through the conduit together with the surplus sizing agent in the sizing pipe for screening treatment.

Sizing agent after the sizing operation is at the in-process with paper or air contact, because the sizing agent is very thick, can glue a lot of impurity or paper wool in the sizing agent, can influence the quality of sizing agent if reuse this moment, consequently through adopting above-mentioned technical scheme, at the top installation shale shaker of dispersion tank, the quality of sizing agent in the dispersion tank can be entered into in the improvement after the shale shaker screening, has guaranteed the whole quality and the effect of sizing agent from this to help improving the quality of paper products.

The invention is further configured to: and a screen mesh is arranged in the vibrating screen, and the screen mesh is a metal mesh with 40 meshes.

By adopting the technical scheme, the metal mesh with 40 meshes is adopted as the screen, the quality of the metal mesh is better, the use and the cleaning of an operator are facilitated, and the adverse effect on the metal mesh is avoided, so that the service life of the vibrating screen is prolonged.

The invention is further configured to: in step S2, the sizing agent treated by the vibrating screen is reintroduced into the dispersion tank.

Through adopting above-mentioned technical scheme, sizing agent after the screening edulcoration, the quality has obtained effective promotion, and recycling is used once more this moment, can not exert an influence to the paper quality, can also practice thrift the quantity of sizing agent simultaneously, practices thrift the cost, improves the reuse rate of sizing agent.

The invention is further configured to: in step S2, the sizing agent that has not passed through the vibrating screen is discharged from the waste liquid pipe and then subjected to secondary screening treatment.

Impurity amount in addition is more in the sizing agent after circulating many times, and the sizing agent that does not pass through the shale shaker this moment can long-pending top of staying at the screen cloth, and long-pending sizing agent can influence the efficiency of later stage screening, consequently through adopting above-mentioned technical scheme, the sizing agent of the shale shaker that will not pass is discharged from the waste liquid intraductal, adopts the quality of screening processing back purification sizing agent once more, and the re-introduction is recycled to the dispersion tank, has practiced thrift the resource, has further improved the availability factor of sizing agent.

The invention is further configured to: 100 parts of edible starch, 0.05-0.1 part of amylase, 0.05-0.1 part of propyl benzene sizing agent, 0.05-0.1 part of aluminum sulfate, 0.02-0.05 part of defoaming agent and the balance of water.

By adopting the technical scheme, the propyl benzene sizing agent has the main component of propyl benzene, and can be used as a bonding agent and matched with adhesives such as edible starch. The pH value of the aluminum sulfate can be adjusted to ensure that the sizing agent is weakly acidic, and the aluminum sulfate also has the function of neutralizing the anionic garbage on the surface of the paper; meanwhile, the aluminum sulfate has positive charges, the fibers have negative charges, retention of fine fibers and fillers is increased, dehydration of a net part is accelerated, and dryness of paper is improved. In addition, the defoaming agent mainly can reduce the generation of foams in the process of preparing the sizing agent, thereby being beneficial to reducing the generation of bubbles on the surface of paper during sizing and being beneficial to improving the uniformity of the paper after sizing.

The invention is further configured to: the edible starch is one or more of corn starch, sweet potato starch, wild acorn starch and kudzu root starch.

By adopting the technical scheme, the corn starch, the sweet potato starch, the wild acorn starch and the kudzu root starch are common starch types, in addition, the plants such as the corn, the sweet potato and the like are low in price and high in starch content, and the wild acorn and the kudzu root also have more starch content, so that the wild acorn and the kudzu root starch can also be used as the supply source of the starch, and the supply amount and the diversity of the supply source of the starch are ensured.

The invention is further configured to: the sizing device comprises an upper rubber roll, a lower rubber roll and two sizing tubes, paper passes through a gap between the upper rubber roll and the lower rubber roll, the sizing tubes are arranged above the upper rubber roll and the lower rubber roll, two ends of each sizing tube respectively extend along the length direction of the upper rubber roll and the lower rubber roll, a plurality of spray heads are arranged, and the heads of the spray heads are obliquely arranged towards the mutual extrusion positions of the upper rubber roll and the lower rubber roll.

Through adopting above-mentioned technical scheme, pass the clearance between the upper and lower rubber roll with the paper, flow into the V type position between the upper and lower rubber roll with the sizing agent via the shower nozzle simultaneously to overflow at above-mentioned V type position department, increased the area of contact between paper and the sizing agent from this for the tow sides of paper are glued simultaneously, and efficiency is higher.

The invention is further configured to: the upper rubber roller and the lower rubber roller comprise an upper rubber roller and a lower rubber roller which are extruded mutually, and a hard rubber sleeve with the hardness of 100 is sleeved on the upper rubber roller; and a soft rubber sleeve with the hardness of 92 is sleeved on the lower rubber roller.

Through adopting above-mentioned technical scheme, the rigid rubber cover of 100 hardness is established to the cover on last rubber roll, and the cover is equipped with the soft rubber cover of 92 hardness on the rubber roll down, and the clearance between the rubber roll passes about the paper dashes this moment, and upper and lower rubber roll extrudes the paper each other, and certain elastic deformation can take place for the soft rubber cover, can reduce the hourglass gluey phenomenon of upper and lower rubber roll from this, can guarantee that the sizing agent flows back to the collection box from the both sides of upper and lower rubber roll and collect, has effectively improved the recycle efficiency of sizing agent. In addition, the elastic deformation capability of the soft rubber sleeve can also reduce the probability of paper breaking and improve the efficiency of paper production.

The invention is further configured to: the soft rubber sleeve is in an arch shape with a high middle and two low ends, and the buckling width of the upper rubber roller and the lower rubber roller is 15-20 mm.

Through adopting above-mentioned technical scheme, the arch sets up, has improved the extruded compactness between upper and lower rubber roll on the one hand, has effectively reduced the hourglass of upper and lower rubber roll and has glued the phenomenon. On the other hand, the trend that the center parts of the upper rubber roll and the lower rubber roll flow towards two sides can be increased, the backflow efficiency and speed are improved, and the rubber roll backflow device is very convenient.

In conclusion, the invention has the following beneficial effects:

1. according to the invention, by controlling the viscosity and concentration of starch and the diameters and buckling widths of the upper and lower rubber rollers, the occurrence of paper breakage can be effectively reduced, and the production efficiency of paper is improved;

2. by arranging the vibrating screen, the overall quality and effect of the sizing agent are ensured, so that the quality of the paper product is improved;

3. through setting up stereoplasm rubber sleeve and soft rubber sleeve, help reducing the hourglass of upper and lower rubber roll and glue the phenomenon, can also reduce the probability of disconnected paper simultaneously, improve the efficiency of paper production.

Drawings

FIG. 1 is a perspective view of the present embodiment 1;

FIG. 2 is a left side view of the present embodiment 1, which is mainly used for showing the paper transportation process and the relative position relationship between the paper and the upper and lower rollers;

FIG. 3 is a perspective view of another angle in the embodiment 1, which is mainly used to show the relative positions and connection relationships among the dispersion tank, the cooking barrel, the stirrer and the gluing barrel;

fig. 4 is a flow chart of the arrangement of the sizing agent in this example 9.

Description of the drawings: 1. a dispersion tank; 2. a cooking barrel; 3. a stirrer; 4. gluing a barrel; 5. paper; 6. a transfer roller; 7. a sizing device; 8. a lift pump; 9. feeding a rubber tube; 10. a spray head; 11. upper and lower rubber rollers; 12. a guide roller; 13. a recycling bin; 14. a conduit; 15. vibrating screen; 16. screening a screen; 17. a waste liquid pipe; 18. gluing a rubber roller; 19. a rubber roller is arranged; 20. a hard rubber sleeve; 21. a soft rubber sleeve.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

In which like parts are designated by like reference numerals. It should be noted that the terms "front," "back," "left," "right," "upper" and "lower" used in the following description refer to directions in the drawings, and the terms "bottom" and "top," "inner" and "outer" refer to directions toward and away from, respectively, the geometric center of a particular component.

Example 1: a soaking type surface sizing process is used for a surface sizing method of AA-level high-strength corrugated base paper, and comprises the following operation steps:

step S1, preparation of sizing agent: the sizing agent comprises 100 parts of edible starch, 0.05-0.1 part of amylase, 0.05-0.1 part of propyl benzene sizing agent, 0.05-0.1 part of aluminum sulfate, 0.02-0.05 part of defoaming agent and the balance of water. Wherein, the concentration of the edible starch is 4-6%, and the viscosity of the edible starch is 20, and the edible starch is 19-25% of the edible starch which is fed into the rubber roller; and the types of amylase are as follows: liquid 2589 amylase.

Step a, putting the edible starch and the water into the dispersion tank 1 according to the proportion and stirring uniformly. Wherein the edible starch is mixed starch of corn starch and sweet potato starch.

And b, heating water to 93-95 ℃, adding the water into the cooking barrel 2, starting the stirrer 3, then putting the edible starch and the amylase in the dispersion tank 1 into the cooking barrel 2, uniformly stirring, stirring for 30-45min, heating to 95 ℃, preserving heat, and cooking for 1h to obtain the sizing agent.

And c, adding the propyl benzene sizing agent, the aluminum sulfate and the defoaming agent into the sizing agent in the cooking barrel 2 while stirring, stirring for 20-25min, cooling to 80-90 ℃, and transferring to a sizing barrel 4 for heat preservation and storage.

And step S2, conveying the paper 5 dried to 92% dryness into a sizing device 7 through a conveying roller 6, conveying the sizing agent obtained in the step c into a sizing pipe 9 through a lifting pump 8, and spraying the sizing agent between an upper rubber roller 11 and a lower rubber roller 11 through a spray head 10. Then the paper 5 passes through the gap between the upper and lower glue rollers 11, and the sizing agent is uniformly coated on the front and back surfaces of the paper 5 under the mutual extrusion of the upper and lower glue rollers 11.

Step S3 is to guide the paper 5 subjected to sizing in step S2 out of the sizing device 7 through the guide roller 12.

Wherein, the paper pulp (raw material) is subjected to mesh forming, squeezing, pre-drying, sizing, post-drying, reeling and rewinding operations to obtain the finished paper. And the sizing device 7 can be used for coating sizing agents on the front side and the back side of the paper 5 so as to improve the good liquid resistance and adaptability of the paper 5, improve the physical strength of the paper 5 and reduce the two-sided performance and deformation of the paper. As shown in fig. 1 and 2, the glue applicator 7 includes a glue application roller 18, a glue application roller 19, and two glue application tubes 9. Wherein, the diameter of the upper glue roller 18 and the lower glue roller 19 is 850-950cm, and the upper glue roller 18 and the lower glue roller 19 rotate reversely and extrude each other; meanwhile, the paper 5 is conveyed from the conveying roller 6 to a position between the upper rubber roller 11 and the lower rubber roller 11 and passes through the position between the upper rubber roller 11 and the lower rubber roller 11. Meanwhile, each gluing pipe 9 extends along the length direction of the gluing roller 18 or the lower gluing roller 19 and is arranged above the gluing roller 18 or the lower gluing roller 19. Thirteen spray heads 10 are arranged on each rubber feeding pipe 9 at intervals, and the head of each spray head 10 is obliquely arranged towards the mutual extrusion part of the upper rubber roller 11 and the lower rubber roller 11. Therefore, the paper 5 can be partially immersed in the sizing agent, the contact area between the paper 5 and the sizing agent is increased, and the sizing efficiency of the paper 5 is further improved.

In order to reduce the glue leakage phenomenon, as shown in fig. 2, the upper and lower glue rollers 11 include a upper glue roller 18 and a lower glue roller 19 which are extruded with each other, wherein a hard rubber sleeve 20 with the hardness of 100 is sleeved on the upper glue roller 18; and a soft rubber sleeve 21 with the hardness of 92 is sleeved on the lower rubber roller 19. Meanwhile, the soft rubber sleeve 21 is in an arch shape with a high middle and two low ends, and the buckling width of the upper and lower rubber rollers 11 is 15-20 mm.

In order to facilitate the arrangement of the sizing agent, as shown in fig. 3, a dispersion tank 1, a cooking barrel 2 and a sizing barrel 4 are installed below an upper rubber roll 11 and a lower rubber roll 11. Wherein, the sizing agent that rubberizes the bucket 4 in the lateral wall installation lift pump 8 can be located rubberizing bucket 4 promotes to rubberizing 9 in the sizing treatment.

Example 2: a soak-type surface sizing process which differs from example 1 in that: the edible starch is mixed starch of corn starch, sweet potato starch and radix Puerariae starch.

Example 3: a soak-type surface sizing process which differs from example 1 in that: the edible starch is mixed starch of corn starch, wild acorn starch and kudzu root starch.

Example 4: a soak-type surface sizing process which differs from example 1 in that: the edible starch is wild acorn starch.

Example 5: a soak-type surface sizing process which differs from example 1 in that: the edible starch is mixed starch of corn starch, sweet potato starch, wild acorn starch and radix Puerariae starch.

Example 6: a soak-type surface sizing process which differs from example 1 in that: in step S2, the excessive sizing agent between the upper and lower rollers 11 can flow into the recycling bin 13 from both sides of the upper and lower rollers 11, and flow into the vibrating screen 15 through the conduit 14 together with the excessive sizing agent in the sizing pipe 9 for screening. Wherein, the vibrating screen 15 is installed above the dispersing tank 1, and the vibrating screen 15 is driven by the eccentric wheel, and the vibrating screen 15 is installed with the screen 16, and the screen 16 is 40 mesh metal mesh. Therefore, the reflowed or overflowed sizing agent can enter the dispersing tank 1 again for reutilization after being screened by the vibrating screen 15, and the utilization rate of the sizing agent is effectively improved.

Example 7: a process for the dip-sizing of surfaces, as shown in figures 1 and 3, comprising the following operating steps:

In the step a, the edible starch and the water are put into the dispersing tank 1 together with the sizing agent after the screening treatment according to the proportion and are stirred uniformly. Wherein the edible starch is sweet potato starch.

And step S2, conveying the paper 5 dried to 92% dryness into a sizing device 7 through a conveying roller 6, conveying the sizing agent obtained in the step c into a sizing pipe 9 through a lifting pump 8, and spraying the sizing agent between an upper rubber roller 11 and a lower rubber roller 11 through a spray head 10. Then the paper 5 passes through the gap between the upper and lower glue rollers 11, and the upper and lower glue rollers 11 extrude each other to make the sizing agent uniformly coated on the front and back surfaces of the paper 5.

Subsequently, the surplus sizing agent between the upper and lower glue rollers 11 can flow into the recycling box 13 from both sides of the upper and lower glue rollers 11, and flow into the vibrating screen 15 through the conduit 14 together with the surplus sizing agent in the sizing pipe 9 for screening treatment. Wherein, the vibrating screen 15 is installed above the dispersing tank 1, and the vibrating screen 15 is driven by the eccentric wheel, and the screen 16 is installed in the vibrating screen 15, and the screen 16 is 40 mesh metal mesh.

Then, the sizing agent treated by the vibrating screen 15 flows into the dispersing tank 1 again from the conduit 14 for recycling; and the sizing agent that has not passed through the vibrating screen 15 is discharged from the waste liquid pipe 17 and then subjected to secondary screening treatment.

Example 8: a soak-type surface sizing process which differs from example 1 in that: in the step a, the edible starch and the water are put into the dispersing tank 1 together with the sizing agent after the screening treatment according to the proportion and are stirred uniformly. Wherein the edible starch is mixed starch of corn starch and sweet potato starch.

Example 9: a soak-type surface sizing process which differs from example 1 in that: the sizing agent is adapted differently. As shown in fig. 4, the method for preparing the sizing agent specifically comprises the following steps:

firstly, weighing edible starch (mainly corn starch) stored in a starch bin by a metering screw, adding the edible starch and water into a dispersion tank 1 together for uniform dispersion treatment, wherein the starch concentration of the dispersion tank is preset to be 25%; then adding amylase and then mixing and stirring; and then screening the uniformly mixed corn flour starch by a vibrating screen 15, conveying the corn flour starch into a cooking barrel 2 by a first ejector, raising the temperature to 75-80 ℃ under the action of steam, and cooking.

Then transferring the corn starch mixed colloid in the cooking barrel 2 into an enzyme reaction tank, and preserving the temperature for 1h to ensure that the corn starch is subjected to primary gelatinization reaction under the action of amylase; then the mixture is transferred into the cooking barrel 2 again through an ejector under the action of a discharge screw pump, the temperature of the cooking barrel 2 is raised to 125 ℃ at the moment, gelatinization reaction is continued for 15-20min, and the viscosity range is controlled: 20 to 40 mPas (63 ℃ C., at 8% concentration), and circulating for 3 to 4 times.

And finally, the sizing agent in the cooking barrel 2 passes through a steam separator, and is guided into the sizing barrel 4 after redundant steam is removed, so that the configuration operation of the sizing agent can be completed.

Test one: ring pressure detection of paper

Test subjects: using examples 1-9 as test samples, 10 groups of small samples of 85g, 90g, 100g, 110g and 120g of paper (i.e. AA-grade high-strength corrugated base paper) were respectively taken for testing; the base paper without size treatment was used as comparative examples, while 10 groups of 85g, 90g, 100g, 110g and 120g of comparative samples were respectively used for the tests.

The test method comprises the following steps: according to the ring pressure detection method of the paper: 1. taking a paper sample after paper is unloaded; 2. putting the paper pattern into the ring pressure sampler from the left side, and holding the handle to press down; 3. the paper sample 152 x 12.7mm was cut and the sample was removed below the sampler. 4. Selecting a ring-crush test seat according to the gram weight, and inserting the paper strip into the test seat; 5. putting the test seat in the middle of the pressure plate and the tray, and placing the test seat in the middle of the lower pressure plate; 6. pressing the 'quantitative' key to input paper sample quantitative, and pressing the 'test' key to test; 7. reading data, comparing with standard, judging and recording, and taking out the test seat to return.

And (3) test results: the detection results of each group of paper in the test samples 1 to 9 all meet the data shown in the following table 1; the average values of the test data of comparative sample 1 were outside the range defined in Table 1. It can be seen that the papers produced in the test samples 1 to 9 all meet the paper ring pressure detection standard.

Table 1 standard ring crush test data of AA-grade high strength corrugated base paper

The specific embodiments are only for explaining the present invention, and the present invention is not limited thereto, and those skilled in the art can make modifications without inventive contribution to the present embodiments as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. A soaking type surface sizing process is characterized in that: comprises the following steps of the following operation steps,

step S1, preparation of sizing agent: the sizing agent comprises edible starch, amylase, propyl benzene sizing agent, aluminum sulfate, defoaming agent and water, wherein the concentration of the edible starch is 4-6%, and the viscosity of the edible starch is 20-25%;

step a, putting edible starch and water in proportion and the sizing agent after screening treatment into a dispersion tank (1) and stirring uniformly;

b, heating water to 93-95 ℃, adding the water into a cooking barrel (2), starting a stirrer (3), then putting the edible starch and amylase in the dispersion tank (1) into the cooking barrel (2), uniformly stirring, stirring for 30-45min, heating to 95 ℃, preserving heat, and cooking for 1h to obtain a sizing agent;

c, adding the propyl benzene sizing agent, the aluminum sulfate and the defoaming agent into the sizing agent in the cooking barrel (2) while stirring, stirring for 20-25min, cooling to 80-90 ℃, and transferring to a sizing barrel (4) for heat preservation and storage;

step S2, conveying the paper (5) dried to 92% dryness into a sizing device (7) through a conveying roller (6), conveying the sizing agent obtained in the step c into a sizing pipe (9) through a lifting pump (8), and spraying the sizing agent between an upper rubber roller and a lower rubber roller (11) through a spray head (10); then the paper (5) passes through a gap between the upper rubber roll and the lower rubber roll (11), and under the mutual extrusion of the upper rubber roll and the lower rubber roll (11), the sizing agent is uniformly coated on the front surface and the back surface of the paper (5), and the paper (5) is partially immersed in the sizing agent;

step S3, guiding out the paper (5) which is finished sizing of the step S2 from the sizing device (7) through a guide roller (12);

the sizing device (7) comprises an upper rubber roll (11), a lower rubber roll (11) and two upper rubber rolls (9), paper (5) penetrates through a gap between the upper rubber roll and the lower rubber roll (11), the upper rubber rolls (9) are arranged above the upper rubber roll and the lower rubber roll (11), two ends of each upper rubber roll (9) respectively extend along the length direction of the upper rubber roll and the lower rubber roll (11), a plurality of spray heads (10) are arranged, and the heads of the spray heads (10) are obliquely arranged towards the mutual extrusion parts of the upper rubber roll and the lower rubber roll (11);

the upper rubber roller and the lower rubber roller (11) comprise an upper rubber roller (18) and a lower rubber roller (19) which are extruded mutually, and a hard rubber sleeve (20) with the hardness of 100 is sleeved on the upper rubber roller (18); the lower rubber roll (19) is sleeved with a soft rubber sleeve (21) with the hardness of 92.

2. The process of claim 1, wherein: in step S2, the surplus sizing agent between the upper and lower rubber rollers (11) flows into the recycling box (13) from both sides of the upper and lower rubber rollers (11), and flows into the vibrating screen (15) through the conduit (14) together with the surplus sizing agent in the upper rubber roller (9) for screening treatment.

3. The process of claim 2, wherein: a screen (16) is arranged in the vibrating screen (15), and the screen (16) is a metal mesh with 40 meshes.

4. The process of claim 3, wherein: in step S2, the sizing agent treated by the vibrating screen (15) is reintroduced into the dispersion tank (1).

5. The process of claim 4, wherein: in step S2, the sizing agent that has not passed through the vibrating screen (15) is discharged from the waste liquid pipe (17) and then subjected to secondary screening treatment.

6. The process of any one of claims 1 to 5, wherein: the sizing agent comprises the following components in parts by weight: 100 parts of edible starch, 0.05-0.1 part of amylase, 0.05-0.1 part of propyl benzene sizing agent, 0.05-0.1 part of aluminum sulfate, 0.02-0.05 part of defoaming agent and the balance of water.

7. The process of claim 6, wherein: the edible starch is one or more of corn starch, sweet potato starch, wild acorn starch and kudzu root starch.

8. The process of claim 7, wherein: the soft rubber sleeve (21) is in an arch shape with a high middle and two low ends, and the buckling width of the upper and lower rubber rollers (11) is 15-20 mm.