KR100520464B1 - Pulp quantity increasing method and paper making method using the same - Google Patents

Abstract

      The present invention relates to a pulp increasing method and a papermaking method using the same, the pulp increasing method according to the present invention is a long fiber pulp disintegration step of pulping by mixing coniferous pulp with water, the pulp feedstock is the Canadian standard Yeosu (CSF ) A beating step of beating to 250 to 650 ml, an increase step of crosslinking cellulose and hemicellulose by adding resorcinol aldehyde and aluminum cellulose or ammonium aluminum cellulose to the beaten material, a pH adjusting agent and a sizing agent It consists of a composition step of adding a wet strength enhancer, the papermaking method according to the present invention is a papermaking step of forming a homogeneous papermaking step, followed by dehydration, drying of the paper stock increased according to the pulp increasing method described above. A resin nose for forming a resin layer on at least one surface during or subsequent to the above papermaking step It is composed of a planting step, and the raw paper produced according to the method of the present invention is significantly reduced in the use of pulp, which can reduce the foreign currency outflow caused by pulp import, contribute to the protection of forest resources, and also contribute to the protection of the global environment. In addition, microscopically, it is possible to reduce the manufacturing cost during papermaking, and exhibit excellent tensile, tear, and tear strength characteristics while having excellent economical efficiency, and thus can be utilized as various printing papers, toilet paper, and wallpaper of high-quality lipids.

Description

PULP QUANTITY INCREASING METHOD AND PAPER MAKING METHOD USING THE SAME}

      The present invention relates to a pulp increasing method and a papermaking method using the same, and more particularly, by adding resorcinol aldehyde and aluminum cellulose to natural pulp to react with hydroxy groups of cellulose and hemicellulose to hemiacetal A pulp increasing method and a papermaking agent capable of imparting good strength properties by increasing this to 200-250% of the initial pulp amount by reacting the hemiacetal with other cellulose and hydroxyl groups of hemicellulose to form acetal formed by crosslinking. It is about a method.

      The conventional papermaking process generally consists of a composition process, a papermaking process, a coating process, and a finishing process, and the coating process is an optional process. The composition process is to make raw materials and subsidiary materials (chemical additives, etc.) into papers suitable for paper making, and to supply them to paper machine. In the papermaking process, the raw materials are subjected to selection and cleaning using paper machine equipment. It is a step of making paper by pressing, drying, etc. after spreading it in a certain amount and thickness per unit area on felt by spraying, dipping extraction, coating, etc., and coating process as an optional process is produced in papermaking process. The coating layer is formed by coating an organic or inorganic material on the raw paper, and the final process is cutting and packing the produced raw paper with paper of a certain size in accordance with the demands and uses of the consumer.

      In more detail, the general papermaking process described above is first introduced into the pulp through the feeder, in which the pulp is mixed with water to release the fibers (dissociation or understanding), and the screen is removed from the pulp. Various foreign substances such as vinyl, etc. in the transferred raw materials are filtered out, and in confession, the selected pulp is cut and fluffed to a certain length to improve bonding strength between the pulp to improve quality such as paper strength.

      The pulp liquid that has passed through the blast furnace is transferred to a mixing tank or mixing box, where various chemical additives (additives) such as a pH adjusting agent, a sizing agent, a wet strength enhancer, etc. are added to the pulp liquid prepared in the composition process, and mixed uniformly. The agitator is made from the batt or the spraying or coating head box by pulverizing, spraying or applying the above-mentioned mixture of pulp and subsidiary materials in a constant amount, concentration, and speed onto the endless felt. In addition to increasing the binding force between the paper spread on the paper, the primary dewatering, the pressurized dehydrator to remove the moisture of the paper transported from the initial stage to increase the binding force for each area, and to increase the drying efficiency during subsequent drying and reduce energy costs In the dryer, the moisture remaining in the pressurized dewatered pulp is removed to the same moisture content as the finished product. If desired, the surface may be ironed and smoothed to smooth the rough surface, and if necessary, an organic or inorganic material may be optionally coated by a coater to form a coating layer, which may be used between the papermaking process and the finishing process described below. It can also be carried out in, the winding machine is wound in a large roll state to produce a base paper. The paper machine may be used to mean a device in which assemblies such as a mixing tank, an agitator, a pressurized dehydrator, a dryer, a cleaner, a winder, and the like are combined.

      In the finishing process following the papermaking process, the rolled large roll is cut into a marketable size as a product according to the demand of the consumer, and the cutter and / or rewinder are laminated or re-wound, followed by muting, labeling, and specification marking. And so on, the finished product is produced.

      In Korea, most of the pulp depends on imports, and the consumption of paper is increasing every year as the standard of living improves, resulting in massive foreign currency outflow. Inevitably, it is one of the major causes of accelerated degradation of the global environment.

       Therefore, there have been attempts to artificially increase the amount of natural pulp by chemical treatment, but the paper produced by this method has never been satisfactorily because there is a serious problem that the strength characteristics are greatly reduced.

      The first object of the present invention is to provide a pulp increasing method capable of reducing pulp usage and cost by increasing natural pulp in the range of 200 to 250% and using it as a stock.

      A second object of the present invention is to provide a papermaking method capable of imparting good strength properties despite increasing pulp.

      According to one preferred aspect for achieving the first object of the present invention, the dissolving step of pulping by mixing condensate pulp (NP: Nadel Holtz Pulp), which is a long-fiber pulp with water, pulp material (Refining or Arranging) Mechanically cutting or fibrillating the dissociated fibers at a certain concentration in water to give papermaking properties to pulp fibers. ), An increase step of crosslinking cellulose and hemicellulose by adding resorcinol aldehyde and aluminum celate or ammonium aluminum cellulose to the beaten paper, and adding a pH adjusting agent, a sizing agent, and a wet strength enhancer to the prepared pulp solution. There is provided a pulp increasing method comprising a composition step.

      According to one preferred aspect to achieve the second object of the present invention, the step of spreading the paper stock expanded according to the pulp increasing method of the above aspect, followed by dehydration, drying to form a homogeneous paper (Initial Paper making), optionally a paper coating method comprising a resin coating step of forming a resin layer in the range of 2 to 12 g / m 2 on at least one surface during or subsequent to the above papermaking step.

      Hereinafter, the present invention will be described in more detail.

      Generally, softwood pulp is soft as long fiber pulp, and hardwood pulp is relatively hard as short fiber pulp. The pulp that can be preferably used in the present invention is a long fiber pulp (Nadel Holtz Bleached Kraft Pulp: NBKP), but optionally a short fiber pulp (Laub Holtz Bleached Kraft Pulp: LBKP) It may also be included in an amount of up to 20% by weight.

      In the present invention, when the composition ratio of NBKP is less than 80% by weight and the composition ratio of LBKP is more than 20% by weight, it is not preferable because the strength characteristics of the paper produced may be inferior.

      In addition, the high degree of pulp used in the present invention may vary depending on the relative amounts of NBKP and LBKP and is a very important factor that has a decisive influence on the strength of paper. It should be in the range of about 30 to 40 ° SR), and if it exceeds 650ml, the strength characteristics are inferior, which is not preferable. If it is less than 250ml, it is difficult to expect a synergistic effect accordingly.

      In addition, in the present invention, it is preferable to use bleached chemical pulp because white clean lipids and colors can be obtained. However, in some cases, semichemical pulp or chemical thermomechanical pulp is used, or Mechanical pulp and thermomechanical pulp without bleaching chemical treatment may also be used.

      Resorcinol aldehyde added for pulp expansion dissociates with resorcinol and aldehyde groups in the pulp solution. Resorcinol functions as an adhesive with high wet and dry strength, and aldehyde groups are hydroxy groups of cellulose and hemicellulose. Reacts to form hemiacetals, which hemiacetals crosslink by reacting with other cellulose and the hydroxyl groups of hemicellulose to form acetals, contributing significantly to an increase in the initial pulp volume while imparting good strength properties.

      The addition amount is in the range of 200 to 400 parts by weight, preferably 250 to 350 parts by weight, and more preferably 310 to 340 parts by weight based on 100 parts by weight of the natural pulp on a dry weight basis.

Meanwhile, aluminum celate (Al ₂ (SO ₄ ) ₃ .18H ₂ O) or ammonium aluminum celate (NH ₄ Al (SO ₄ ) ₂ .12H ₂ O) added for pulp increase and pH control may be used for the crosslinking. Participation or adsorption to the bond results in contributing to the pulp increase, most preferred being ammonium aluminum selate.

      The addition amount is in the range of 100 to 250 parts by weight, and preferably in the range of 150 to 200 parts by weight based on 100 parts by weight of the natural pulp on the basis of dry weight of the solid content of 5 to 12% by weight.

      Paper used in the present invention includes a pH adjuster, a sizing agent, a wet strength enhancer.

As the pH adjusting agent used in the present invention, ALUMs such as alum (KAl (SO ₄ ) ₂ ㆍ 12H ₂ O) or potassium hydroxide (KOH) may be used, and the amount of the additive is 3 to 12% by weight of the solid content based on dry weight. In the range of 5 to 20 parts by weight based on 100 parts by weight of natural pulp.

      The sizing agent is added in an amount of 5 to 10 parts by weight based on 100 parts by weight of the natural pulp on a dry weight basis in order to maintain a homogeneous quality through control of water absorption and to improve paper yield due to fine fiber retention, and a rosin-based sizing agent or a solid content of 20 to Although 45% by weight polyamide polyamine epichlorohydrin can be used, polyamide polyamine epichlorohydrin is particularly preferred.

      Wet strength enhancers are added to increase surface strength and improve printability by preventing stakes, and are added to give fine fiber adhesion, improved paper work efficiency and product yield, high retention and wet strength effects, and epoxidized polyamides. In this case, the polyamine may be used in an amount of 2 to 8 parts by weight based on 100 parts by weight of the natural pulp on a dry weight basis.

      In the papermaking method of the present invention, optionally, by including a resin coating layer on at least one side of the base paper to enhance the strength characteristics, there is no particular limitation as long as it is conventionally known in the art as the type of resin to be coated, acrylic resin , Methacryl resin, vinyl resin, silicone resin, polyimide resin, polyurethane resin and the like can be used, and preferably acrylic resin and vinyl resin having high transparency. The acrylic resin may be conveniently used having a solid content of 30 to 60%, and the vinyl resin may be conveniently used with a solid content of 10 to 25%. It is preferable to use those diluted with an appropriate solvent, for example, it is preferable to use toluene or acetone in a mixture of 20 to 40% in terms of uniformity of the coating layer and ease of processing. The amount of the solvent dilution resin solution may be used in an amount of 2-12 g on both sides per 1 m 2 of the base paper, but the amount of the solvent dilution resin is not limited in the present invention, and is optional. The presence of such a resin coating layer may help to improve the hardness and strength characteristics of the base paper.

      In addition, in the present invention, if necessary, instead of the above-mentioned resin coating layer, an inorganic clay or nickel coating layer may be formed to increase gloss and printability satisfactorily, which is also within the scope of the present invention.

      Next, the pulp increasing method and the papermaking method using the same according to the present invention will be described.

      The pulp used for dissociation or understanding in the pulp is NBKP, which is a long fiber pulp, and may optionally contain up to 20 parts by weight of LBKP, a short fiber pulp, mixed with excess water (about 3 to 5 times). It is pulped.

      In the confession stage, the pulverized feedstock will be beaten to 250-650 ml of Canadian Standard Yeosu (CSF). The selection of the appropriate high degree of elongation range is variable depending on the mixing ratio (composition ratio) of the pulp raw materials used, but generally less than 30 ° SR because the strength characteristics may be excessively deteriorated. It is also undesirable because it is difficult to expect a synergistic effect and may lead to undesirable consequences for the increase.

      In the expansion step, resorcinol aldehyde and aluminum selate or ammonium aluminum selate are mixed together in the amounts described above and then slowly added dropwise into the above natural pulp solidified solution. During the dropwise addition, the mixture is stirred at about 40 to 100 rpm.

      In the present invention, the composition step of adding the pH adjusting agent, the sizing agent, and the wet strength enhancer is performed after completion of the dropwise addition in the increasing step, and after adding these additives, about 5 to 24 hours at room temperature, preferably 6 to 6 hours. It is left to mature for about 9 hours to further advance the crosslinking, and at the same time, some extenders which cannot be added to the crosslinking are fixed and aggregated, and the pH adjuster also functions as a neutralizing agent. Please refer to the foregoing for these additives.

      Further, in the above composition step, borax and / or sodium bicarbonate aqueous solution may be used as a fixing agent in an amount of 10 to 30% by weight based on the natural pulp dry weight, and 5 to 20% hydrochloric acid and / or formic acid aqueous solution may be used as a flocculant. It may be used in an amount of 5 to 15% by weight based on the dry weight.

      Optionally, after the composition step described above, a washing step of washing with water about two or three times may be performed.

      According to the pulp increasing method according to the present invention described above, it is possible to increase the initial pulp amount by 200 to 250%.

      In the early stages, we are spreading confessed materials. See above for anxiety. In the present invention, annealing can be performed by a immersion extraction method, a spray method, and a coating method.

      When the papermaking method according to the present invention is described as a floating evaporation by immersion withdrawal method using a bat in the papermaking step as an example, the main roll is partially deposited in the paper in the bat containing the stock (pulp solution) in which the composition step is completed. The driven roll forms a nip press having a constant gap with the main roll. The felt is guided by the guide rolls and passed between the main roll and the driven rolls so that the stock in the batt forms a layer on the felt.

      After the wetting, a papermaking process is performed, which may be made of processes such as dehydration, drying, gloss, (coating), and winding.

      Further, optionally, the resin coating step of forming a resin layer in the range of 2 to 12 g / m2 on both sides during or after the above papermaking step may also be performed. See

      Hereinafter, the present invention will be described in more detail with reference to examples, and it should be understood that these examples are only for illustrating the present invention and are not intended to limit the present invention.

Examples 1 to 5: increase in pulp

     The natural pulp is made from 100 kg of long fiber NBKP and 450 l of water on a dry weight basis, and then the pulp slurry is passed between the main and driven rolls rotating in opposite directions to mechanically treat the pulp. Using a Double Disk Refiner (DDR) which can adjust the degree of latitude at intervals of the rolling roll, take 1/5 of the sample at 0 minutes, 12 minutes, 15 minutes, 18 minutes and 23 minutes respectively. Canadian Standard Freedom (CSF) was measured and in each case CSF 791ml, 612ml, 544ml, 465ml and 339ml.

Subsequently, 320 kg of resorcinol aldehyde and 150 kg of 20% ammonium aluminum celate (NH ₄ Al (SO ₄ ) ₂ .12H ₂ O) aqueous solution were mixed, and then divided into five equal parts and stirred at 50 rpm. Slowly added dropwise.

      After completion of the dropwise addition, 8 kg of polyamide polyamine epichlorohydrin having 25% by weight of solid content as a sizing agent and 5 kg of epoxidized polyamide polyamine having 20% by weight of solid content as a wet strength enhancer were added sequentially with stirring under the same conditions. The pH was adjusted to 7.0 ± 0.5 using 15 parts by weight of an 8% potassium hydroxide (KOH) aqueous solution as a pH adjusting agent, the stirring was stopped, then sealed and left to stand at room temperature for about 12 hours for aging.

      Subsequently, the mixture was washed twice with water and dehydrated to 55% from 75% of water content.

      The pulp combined with the respective parts of the above Examples 1 to 6 was 223 kg on a dry weight basis, and the pulp amount was found to be increased by 223%.

Examples 6 to 10 Preparation of Sheet Paper Using Extended Pulp

      Each of the pulp of Examples 1 to 5 was prepared by the above-mentioned papermaking method, and a papermaking paper having a basis weight of 60 g / m 2 was set as Examples 6 to 10, respectively.

Comparative Examples 1 to 5: Preparation of Sheet Paper Using Non-Extended Pulp

      As in Examples 1 to 5 described above, natural pulp was prepared from 100 kg of long fiber NBKP and 450 L of water on a dry weight basis, and then the beating time was 0 minutes, 18 minutes, 28 minutes, and 33 minutes using a double disk crusher. And 38 minutes each sample was taken by 1/5 and the Canadian standard freeness (CSF) was measured and in each case CS701 was 701 ml, 599 ml, 458 ml, 364 ml and 267 ml.

      8 kg of polyamide polyamine epichlorohydrin with 25% by weight solids as sizing agent and 20% by weight epoxidized polyamide polyamine as wet strength enhancer without addition of resorcinol aldehyde and ammonium aluminum selate for increase 5 kg were added sequentially with stirring under the same conditions as above, and the pH was adjusted to 7.0 ± 0.5 using 15 parts by weight of an aqueous 8% potassium hydroxide (KOH) solution as a pH adjusting agent, the stirring was stopped, then sealed and sealed at room temperature. After aging for 12 hours, the mixture was washed twice with water and dehydrated to obtain 55% of water content from 75%.

      In the same manner as in Example 2 described above, a papermaking paper having a basis weight of 60 g / m 2 was prepared by the floating papermaking method, and Comparative Examples 1 to 5 were used.

Examples 11 and 12: Preparation of Resin Coated Resin Paper

       Toluene was added to a coating liquid consisting of 30% by weight of an acrylic resin of 30% by weight, 50% by weight of a vinyl resin, and 20% by weight of toluene as a solvent, and 30% by weight of an acrylic resin on one side of the sheet of paper of Example 8. The resin coating liquid adjusted to the solid content of 10% by weight was added to prepare a resin paper surface-coated with a coating amount of 5 g / m 2, which was set as Examples 11 and 12, respectively.

Test Example: Evaluation of Strength Properties

       Tensile strength (breaking length), tearing strength (Tear Index) and bursting strength (burst index: Burst) for the paper sheets of Examples 6 to 10, 11, and 12 and Comparative Examples 1 to 5 described above. Index) was evaluated by the Korea Research Institute of Chemical Technology (Jang-dong, Yuseong-gu, Daejeon) and the results are shown in Table 1 below.

No. Confession time (minutes) CSF (Yeosuido) (ml) Tear index (mN.m ² / g) Thermal insulation (Km) Burst Index (KPa.m ² / g) Example 6 0 701 15.0 1.35 0.85 Example 7 18 599 19.6 5.22 3.99 Example 8 28 458 18.1 6.02 4.42 Example 9 33 364 17.0 6.02 4.37 Example 10 38 267 15.2 6.32 4.62 Example 11 15 544 21.6 7.04 6.12 Example 12 15 544 20.8 6.81 6.05 Comparative Example 1 0 791 7.3 2.99 0.64 Comparative Example 2 12 612 18.1 4.05 2.61 Comparative Example 3 15 544 16.1 4.87 3.39 Comparative Example 4 18 465 14.1 5.14 5.56 Comparative Example 5 23 339 13.1 5.12 3.43

       From the above results, the papermaking papers of Examples 8 to 10 prepared by increasing the pulp by about 200 to 250% using the pulp increasing method according to the present invention were tensile, tearing and tearing compared to the papermaking paper prepared using non-extended pulp. It was found to be about 20% lower in strength, but at the same time, the use of general high-quality paper was not overwhelming, and compared with the increase ratio, it was considered as an encouraging result.

       Further, in Examples 11 and 12, wherein the resin paper was coated on one surface of the paper according to the present invention, about 10 to 20% increased in tensile, tear, and burst strength compared to the paper produced using non-extension pulp. It turned out to be.

       While the present invention has been described in detail, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the present invention, but are also within the scope of the present invention. It must be understood.

       As described above, according to the pulp increasing method and the papermaking method using the same according to the present invention, the amount of pulp used is significantly reduced, thereby macroscopically reducing foreign currency outflow by pulp import, contributing to the protection of forest resources and conserving the global environment. At the same time, it is possible to reduce the manufacturing cost during papermaking, and it can be used as various printing papers, toilet paper, and wallpaper of high-quality lipids because it shows excellent tensile, tear and tear strength characteristics while having excellent economic efficiency. .

Claims (10)

       Pulp expansion method comprising the following steps:        (A) dissolving step of mixing and pulping coniferous pulp (NP: Nadel Holtz Pulp), which is a long fiber pulp, with water;        (B) refining or arranging the pulped feed to 250-650 ml of Canadian Standard Freeness (CSF); (C) when resonance the beaten paper stock play aldehyde (resorcinol aldehyde) and aluminum cell rate (Al ₂ (SO _{4) 3} and 18H ₂ O), or ammonium aluminum cell rate _{(NH 4 Al (SO 4)} 2 and 12H ₂ An increase step of crosslinking cellulose and hemicellulose by dropwise adding O); And        (D) a composition step of adding a pH adjusting agent, a sizing agent, a wet strength enhancer to the pulp liquid.        The method according to claim 1, wherein the addition amount of resorcinol aldehyde and aluminum selate or ammonium aluminum selate in the (C) increasing step is 200 to 400 parts by weight based on 100 parts by weight of natural pulp on a dry weight basis and 100-250 parts by weight of pulp increasing method. The pH adjusting agent in the composition step (D) is alum (KAl (SO ₄ ) ₂ .12H ₂ O) or potassium hydroxide (KOH), and the sizing agent is a rosin-based sizing agent or a polyamide polyamine epi. The pulping method of pulping with chlorohydrin, wherein the wet strength enhancer is an epoxidized polyamide polyamine.        The amount of the pH adjusting agent, the sizing agent and the wet strength enhancer is 5 to 20 parts by weight, 5 to 10 parts by weight, and 2 to 8 parts by weight, respectively, based on 100 parts by weight of the natural pulp on a dry weight basis. How to increase pulp. delete        The pulp in the dissociation step (A) is composed of semichemical pulp, chemical thermomechanical pulp, mechanical pulp and thermomechanical pulp. A pulp increasing method, wherein the pulp is at least one pulp selected from the group.       The process according to any one of claims 1 to 4, wherein the (C) increasing step and the (D) (D) composition step are carried out under agitation at 40 to 100 rpm, followed by the (D) composition step ( E) A method of increasing pulp, which further performs the aging step of standing at room temperature for about 5 to 24 hours, (F) water washing step, and (G) dehydration step in order.       Papermaking method consisting of the following steps:       (A) providing a stock produced by the pulp increasing method according to claim 1;       (B) Spreading step carried out in any one method selected from the group consisting of immersion extraction method, spray method and application method; And       (C) Initial Paper Making step to dehydrate and dry to form a homogeneous paper.       The papermaking method according to claim 8, further comprising (D) a resin coating layer forming step of forming a resin coating layer of 2 to 12 g / m 2 on at least one surface of the sheet of paper during or after the papermaking step (C). .       The papermaking method according to claim 9, wherein the resin coating layer is formed of at least one resin selected from the group consisting of acrylic resins, methacryl resins, vinyl resins, silicone resins, polyimide resins and polyurethane resins.