• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    In making paper from an aqueous papermaking stock, a binder comprising colloidal silicic acid and cationic starch is added to the stock for improving the paper or the retention of the stock components, or is added to the white water for reducing the pollution problems or recovering values from the white water. The cationic starch of the binder has a degree of substitution of not less than 0.01, and the weight ratio of cationic starch to SiO2 is between 1:1 and 25:1.
    公开号:SU1228793A3
    申请号:SU813315051
    申请日:1981-05-27
    公开日:1986-04-30
    发明作者:Санден Олоф；Гуннар Ботелсон Пер；Эрик Йоханссон Ханс；Магнус Ларссон Ханс；Йохан Свендинг Пер
    申请人:Ека Аб (Фирма)；
    IPC主号:
    专利说明:

    The invention relates to the pulp and paper industry, in particular to paper sizing.
    The purpose of the invention is to increase the strength of paper containing at least 50% cellulose fibers in its stock.
    The essence of the invention lies in the fact that according to the method of making paper, which includes introducing a binder containing cationic starch and colloidal silicic acid into the fibrous suspension, pouring the paper web and drying it, binder is introduced into the fibrous suspension at a mass ratio of cationic starch to SiO, 1: 1 - 25: 1, using cationic starch with a degree of substitution of 0.02-0.05.
    The proposed method significantly increases the strength and other characteristics of the paper, which allow the use of significant amounts of mineral fillers in the paper making process with an increased retention of filler in the cellulose fibers in the sheet. This makes it possible to reduce the content of cellulosic fibers and / or the quality of cellulosic fibers used without compromising the strength and other characteristics of the paper. By using the principles of the invention, the amount of mineral filler can be increased without reducing the strength and other characteristics of the finished paper. Thus, by reducing the amount of pulp used for a sheet of paper or replacing it with mineral filler, reducing the fiber content reduces the energy required to make it, and also reduces the energy used for drying. In addition, the retention of mineral filler and fine particles is at a sufficiently high level which minimizes the problems of cleaning white paper.
    According to the method, the binder contains a ukit combination; it is a colloidal silicic acid and cation starch. The acid can have several forms, for example, the form of polysilicic acid of colloidal silicic acid and sols, although the best results are obtained using colloidal silica sols.
    Polycrmic acid can be obtained by reacting the liquid stack.
    s
    0
    five
    0
    la with sulfuric acid using known processes to provide .molecular weight (as in SiO ,,) up to 1,000,000. However, the resulting polysilicic acid is unstable and difficult to use because of the presence of sodium sulfate is corrosive. Sodium sulphate can be removed by ion exchange, but the resulting polysilicon is unstable and will be destroyed without refrigeration when stabilized. Salt-free polysilicic acid can also be obtained by direct ion exchange of diluted water glass.
    Although substantial improvements in strength and holding were obtained with a binder containing polysilicic acid and cationic starch, better results were obtained when using cationic starch of colloidal silicic acid in the form of a sol containing 2-60% by weight of SiO, preferably 2- thirty%.
    Colloidal silicic acid in the form of ash should have a specific surface of 50-1000, preferably, with the best results of 300-700. The silica sol is stabilized with an alkali having
    the molar ratio of SiO and
    10 .: 1-300: 1, preferably 16: 1-100: 1 (M-ion selected from the group containing sodium, potassium, lithium, and NH, to it). The particle size of colloidal silicic acid should be up to 20 nm, preferably 10–1 nm on average (particles of colloidal silicic acid have a specific surface of about 500 m / g, an average size of 5, 5 nm).
    It is desirable to use silica sol having colloidal silicic acid particles that have a maximum active surface and an average size of 4-9 nm.
    five
    Cationic starch, which is used in the binder, can be produced from starches made from any known starch-containing substances,
    0 for example, corn wheat, rice and potato starches, etc. Starch becomes cationic by replacing the ammonia group. The best results were obtained with a degree of substitution of 0.01-0.05, preferably 0.02-0.04, with the most favorable interval being 0.025-0.04. Although a variety of ammonia compounds can be used, it is preferable to use cationized starch, which is prepared by basic starch, or 3-chloro-2-hydroxypropyl-trimethylammonium chloride or 2,3-epoxypropyl-trimethylammonium chloride to obtain cationized starch having a degree of substitution of 0.02-0.04.
    In the papermaking process, the binder is added to the pulp before paper is made on the paper machine.
    The first addition of two ingredients — colloidal silicic acid and cationic starch — can be mixed together to form an aqueous mixture, which can then be added and mixed with the mass. However, this procedure does not provide maximum results. It is desirable that a mixture of silicon oxide and cationic starch be formed essentially in the raw mass. This can be done by adding colloidal silicic acid in the form of an aqueous sol and cationic starch in the form of an aqueous solution separately into the mass in the mixer or in the place of the system where uniform mixing takes place so that both components disperse with the pulp, interact with each other, and paper furnish at the same time.
    The best results are obtained if colloidal silicic acid is added to a part of the mass and is evenly mixed with it, after which the mass production is completed and the cation starch is added and mixed with the mass to obtain a paper product.
    If the mineral filler is added to the mass, it is desirable to dilute it in water with colloidal silicon.
    20
    constitutes 20-90% of the total amount of the substance added, and after receiving the initial agglomerate (before the sheet is obtained), residue is added. It is desirable that the initial per serving contain 30-80% colloidal acid.
    When used in paper production, the described complex binding weight of paper is not critical and can be in the range of 4-9. However, a pH range of 9 and below 4 is undesirable. In addition, other chemicals may be used to make paper, for example, binders, alum, and the like. but it is necessary that the level of such additives should not exceed the allowable one, which affects the formation of silicic acid agglomerate and cationic starch, and that the level of agent in the recirculating water should not exceed the level at which the formation of binder agglomerate is disturbed. Therefore, it is usually necessary to add a reagent to the system when an agglomerate is obtained.
    According to the invention, the ratio of cationic starch to the total content of collorous silicic acid should be 1: 1-25: 1 by weight. It is desirable that this ratio be in the range of 1.5: 1-10 And, even better, 1.5: 1-4.5: 1.
    The amount of binder that needs to be used varies depending on the effect desired, as well as the characteristics of the components that are selected to make up the binder. For example, if the binder includes polysilicic acid as a colloidal component, you need to add more binder than if the colloidal component is 30
    35
    40
    „4S with
    evoic acid, and if the acid is added a sol, having a specific field periodically, then the initial part of it. The mixture of the filler and the acid is then introduced into the mixer where it is mixed with the mass and cationic starch.
    After the periodic addition of silicic acid, the latter part is mixed with the mass after the initial agglomerate is obtained, and before the mass is introduced into the pressure tank. Initial addition of colloidal silicic acid
    -
    ten
    20
    2287934
    makes up 20-90% of the total amount of substance added, and after the initial agglomerate is obtained (before the sheet is obtained), the residue is added. Preferably, the initial portion contains 30-80% colloidal acid.
    When used in papermaking of the described complex binder, the pI of the paper weight is not critical and may be in the range of 4-9. However, a pH range of 9 and below 4 is undesirable. In addition, other chemicals can be used to make paper, for example, binders, alum, and the like. but it is necessary that the level of such additives not exceed the allowable one, which affects the formation of silicic acid agglomerate and cationic starch, and that the level of agent in the recirculating water does not exceed the level at which the formation of the binder agglomerate is disturbed. Therefore, it is usually necessary to add a reagent to the system when an agglomerate is obtained.
    According to the invention, the ratio of cationic starch to the total content of colloric silicic acid should be 1: 1-25: 1 by weight. It is desirable that this ratio be in the range of 1.5: 1-10 And, even better, 1.5: 1-4.5: 1.
    The amount of binder that needs to be used varies depending on the effect desired, as well as the characteristics of the components that are selected to make up the binder. For example, if the binder includes polysilicic acid as a colloidal component, it is necessary to add more binder than if the colloidal component is 30
    35
    40
    4S with
     l l a sol having a specific value of 50
    surface 300-700 m / g. When the degree of absorption of cationic starch is, for example, 0.025 compared with the degree of absorption of 0.030, a larger amount of binder is necessary, taking into account that the colloidal silicic acid remains unchanged.
    When the raw material does not contain a mineral filler, the level of the binder may be in the range of 1-15% by weight of cellulose fiber. If mineral filler is used
    S
    then the amount of binder can be calculated by weight of the filler, which will be 0.5-25%, usually 2.5-15%. Example 1. On a laboratory device, paper was made from various raw materials obtained from clarified soft sulphate pulp with wollastonite as a filler and without it. Raw materials include the complex composition of cationic starch and colloidal silicic acid to obtain enhanced properties of the final product. Wollastonite is used in the form of needle crystals with a diameter of 1–20 nm and a length of pore diameters of 15 diameters.
    The colloidal silicic acid used for the experiment is a sol containing 15% of an acid with a specific surface of approximately 500. The sol is stabilized with an alkali with a molar ratio of SiO:: Na O equal to 40: 1.
    Cationic starch is prepared from potato with 3-chloro-2-hydro-propyl-trimethylammonium chloride to provide a degree of substitution in the starch of the order of 0.03. The cationic starch is added as a 4% solution. The ratio of cationic starch to SiO is from 1: 1 to 4
    In the course of the experiment, a colloidal silicic acid sol is added to the masses to cationic starch. In the examples containing wollastonite, the sol and cationic starch are added with a mineral additive to form a mixture and the mineral binder which is then added to the cellulose. A typical amount of water is added in order to obtain a fibrous mass of the desired viscosity with a content of solid particles in the order of 1%. After the sheet is poured, the sheets are pressed and dried under normal conditions
    In tab. 1 shows the composition for the manufacture of paper and indicators of its quality
    Table

    Continued table. one
    Example 2. On a laboratory machine, paper was made from various raw materials prepared from 0.2 g of clarified soft wood pulp 2.0 g of English white clay of degree C. White clay was dispersed in alkali-stabilized colloidal silicic acid sol, diluted from 15 to 1, 5% solids are contained, and the dispersion is added to the mass with 500 ml of water in a laboratory disintegrator. A 2% solution of cationic starch (degree of substitution 0.03) is added to the mass and. a mixture is obtained which is poured into a mold to form a sheet. Sheets are compressed and dried-1ÜT under the same conditions.
    During the tests, various silicic acid sols having a different specific surface area per unit of weight were used and stabilized with alkali with a different molar ratio.
    I
    Properties of the resulting paper are given in table. 2
    h
    Stabilized with ammonia instead of NaOH, molar rel. „
    starch, only 2.0 g wood pulp + 6 g
    Without Si02, without cationic clay.
    50
    From this example, it is clear that silica sol and cationic starch -. small help significantly in clay retention and in many cases leads to almost complete retention. In addition, these results show that the maximum clay retention occurs when the particles of colloidal silicic acid are of such size that the specific surface is in the range between 300 and 700,
    PRI me R 3. Paper napkins are made in a laboratory setting from a raw material containing a binder, the swarm includes as colloidal
    T; i pancake: i /
    silicic acid, polysilicic acid, 100 ml of water glass (R Si02: 3.3 and SiO 26.5% by weight) are diluted with 160 ml of water and slowly added to 130 ml of 10% sulfuric acid with continuous stirring. When all the glass is added, the pH is 2.7 and the content by weight. Such an acid sol is diluted to 2% SiOj, and added to English white clay C, after which 2% cathine starch in solution is added (substitution degree 0.03). The ratio of cationic starch to SiOg is 1.7: 1: 2.5: 1. In tab. 3 given suspensions.
    9-12.
    T a b l and c a 3
    Each of suspensions 1, 2 and 4 is fed to a laboratory disintegrator containing 2.0 g of clarified soft sulphate pulp in 500 ml of water, and mixed. Suspensions 3 and 5 were stored for 5 hours before mixing. Immediately after mixing, paper sheets are prepared by hand, pressed and dried.
    Indicators of the resulting paper are given in table. four.
    T a b l and c a 4
    28793in
    It is added to various raw paper materials to show that the invention is applicable even in masses containing
    5 significant amounts of non-cellulose fibers.
    Fully clarified soft sulphate woods are used as cellulosic fibers;
    10 as non-cellulosic fiber glass fiber having a diameter of about 5 mm and treated with a phenolic resin. Colloidal silicic acid as a sol contains cream particles (5 with a specific surface area of about 400 and the acid content in the sol is initially 15% by weight, but then the sol is diluted with water to an acid content of about 1.5% before using it. binder system. Cationic starch has a mixing degree of 0.02 and is used in the form of a 2% solution.
    Mass samples were obtained from which
    25 - comparative (see table. 5)
    Table5
    thirty
    1, despite the improved tensile strength, the retention of the mineral filler is not better than in this example.
    PRI me R 4. In this example, the binder system according to the invention of seven mass samples produced sheets of paper in the laboratory equipment.
    In tab. 6 given indicators received paper.,
    Table
    As can be seen from the above data, Z-strength decreases when glass fiber is added (samples 1 and 2), and then increases to the original value (samples 1 and 4) when silica sol and cationic starch are added. Sheets prepared from samples 5, 6, and 7 have higher Z-strength values than sheets made from the mass of OB1.
    0.020 49.0 3.6 2.4
    A2A0.02057,14,22,8
    A3A0.02065,34,83,2
    A4A0.03340,83,02,0
    А5А0,03349,03,62,4
    ten
    raztsa 1 not co / re |., -: ainero fiberglass.
    Example 5. In order to further demonstrate the invention and the effect of various cationic starch substitutions, two series of paper making were performed in a laboratory setup using a mass that contained the same amounts of colloidal silicic acid as a sol, but which contained cationic starch of various degrees of substitution.
    The cationic starch used in this example is prepared from two different basic materials (A and B) to obtain the degrees of substitution indicated in Table. 7
    The whole pulp for preparing sheets was prepared by mixing 1, 09 g of white clay (English white clay C) with 2.72 g of colloidal silicic acid sol (1.5% solids and a specific surface area of 530 m / g) and adding this pulp to the laboratory a disintegrator containing 1.63 g of fully clarified sulfate soft wood of mass in 500 ml of water. After the components are displaced in the disintegrator, cationic starch is added for 30 seconds. The mixing is carried out for 15 seconds and then the pulp is poured into the mold.
    The degree of substitution of various starches and the amount of additives in the pulp, as well as the properties of the sheets are given in Table. 7
    T a b l and c a 7
    20
    25
    thirty
    35
    91.6 619 22.0
    thirty
    EXAMPLE 6 For the manufacture of evoic acid (the surface area of paper is 1.75 g of bleached about 500 m 1g) and cationic starch sulfate double cellulose, 0.75 gmAl with a degree of substitution of 0, Q45 chalk and 500 ml of water. . To received May-in the quantities listed in the table. A colloidal silicon-8 sol is added.
    ..Table8
    Additives to the stock are carried out in a laboratory disintegrator. Silicic acid is first added, stirred for 15 seconds, and then added. eight
    a thief cationic starch and stirred 30 s. The sheets of the paper were made by hand, and then dried. The quality of the produced paper is given in table.9.
    g
    Table9
    权利要求:
    Claims (6)
    [1]
    1. METHOD FOR PAPER MANUFACTURE, comprising introducing into a fibrous suspension a binder containing cationic starch and colloidal silicic acid, casting a paper web and its sum, characterized in that, in order to increase the strength of paper containing at least 50% cellulose fibers, a binder is introduced into the fibrous suspension by the mass ratio of cationic starch to SiO 2 1: 1 -25: 1, using cationic starch with a degree of substitution of 0.02-0.05.
    [2]
    2. The method according to claim 1, characterized in that colloidal silicic acid containing SiO z particles with a surface area of 200-900 m 2 / g is used.
    [3]
    3. The method according to PP. 1 and 2, characterized in that the binder is introduced into the fibrous suspension in an amount of 1-15% by weight of the cellulose fiber.
    [4]
    4. The method according to PP. 1-3, characterized in that the mineral filler is introduced into the fibrous suspension.
    [5]
    5. The method according to p. 4, characterized in that before introducing into the fibrous suspension of the mineral filler is mixed with colloidal silicic acid.
    [6]
    6. The method according to PP. 1-5, characterized in that 20-90% colloidal silicic acid is introduced into the fibrous suspension, then cationic starch, after which the remainder of the silicic acid is added,
    Priority on points:
    05/28/80 PP 1-5.
    02/26/81 under item 6.
    1228793 AZ
    类似技术:
    公开号 | 公开日 | 专利标题
    SU1228793A3|1986-04-30|Method of papermaking
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    GB1581548A|1980-12-17|Manufacture of paper or cardboard
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    同族专利:
    公开号 | 公开日
    EP0041056B1|1984-08-08|
    MX158106A|1989-01-09|
    BR8103345A|1982-02-16|
    AU7051481A|1981-12-03|
    ES8304247A1|1983-02-16|
    FI811628L|1981-11-29|
    AR231848A1|1985-03-29|
    ES502531A0|1983-02-16|
    FI68283B|1985-04-30|
    DE3165370D1|1984-09-13|
    NO161334C|1989-08-02|
    FI68283C|1985-08-12|
    AT8916T|1984-08-15|
    NZ197223A|1984-05-31|
    NO811811L|1981-11-30|
    EP0041056A1|1981-12-02|
    AU546999B2|1985-10-03|
    NO161334B|1989-04-24|
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    SE9003954L|1990-12-11|1992-06-12|Eka Nobel Ab|SET FOR MANUFACTURE OF SHEET OR SHAPE CELLULOSA FIBER CONTAINING PRODUCTS|
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    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    SE8003948A|SE432951B|1980-05-28|1980-05-28|PAPER PRODUCT CONTAINING CELLULOSA FIBERS AND A BINDING SYSTEM CONTAINING COLOIDAL MILIC ACID AND COTIONIC STARCH AND PROCEDURE FOR PREPARING THE PAPER PRODUCT|
    US06/238,645|US4385961A|1981-02-26|1981-02-26|Papermaking|
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