Crease-resistant, balanced paper having high tensile strength and method of making same

Abstract

The application relates to the technical field of balanced paper, and discloses anti-wrinkle balanced paper with high tensile strength and a preparation method thereof; the anti-wrinkle balanced paper is prepared from wood pulp, white toilet paper, recycled waste paper, fillers such as titanium dioxide and talcum powder, retention aids, reinforcing agents and dyes; the wood pulp is first broken into pulp and then beaten, so that the time cost is reduced; a high-frequency defibrator and a large-beater-plate refiner are used, so that the fiber defibration is complete, and the dispersion uniformity is good; the fillers such as titanium dioxide and talcum powder are added in the process of breaking into pulp and beating, so that the fillers fully contact with the fibers and enter the cell cavities in the process of destroying the cell walls of the fibers; the sodium carboxymethyl cellulose and anionic polyacrylamide are simultaneously added as the retention aids, so that the retention rate of the fillers is improved; the production cost is greatly reduced by replacing the titanium dioxide and talcum powder with part of the recycled dry sludge, and the market competitiveness is improved; finally, the anti-wrinkle balanced paper with high dry tensile strength and wet tensile strength, uniform fiber organization, good interweaving force, high water absorption and good evenness is prepared.

Description

Technical Field

[0001] This invention relates to the field of balancing paper technology, and discloses a high tensile strength anti-wrinkle balancing paper and its preparation method. Background Technology

[0002] In recent years, with increasing global emphasis on environmental protection, solid wood flooring, which consumes vast amounts of forest resources, is being gradually replaced by high-strength composite wood flooring. my country started this work relatively late, and there are no domestic manufacturers specializing in producing the bottom balancing paper, a crucial layer in composite flooring. Therefore, China has had to rely on expensive imports, significantly increasing production costs.

[0003] The existing balancing paper is a special paper used in the production of engineered wood flooring. Engineered wood flooring is generally composed of four layers: a wear layer, a decorative layer, a core layer, and a balancing layer, from top to bottom. The balancing paper is pressed onto the underside of the engineered wood flooring. Its main function is to balance the stress of the board, stabilize the flooring, prevent warping and deformation, and ensure flatness. It also effectively prevents moisture from seeping in from the back of the flooring, improving the product's moisture resistance. In China, balancing paper was initially imported. However, with the increasing application of the product, early manufacturers began producing this paper themselves. After years of effort, the market share of domestically produced balancing paper has been steadily increasing.

[0004] Currently, the fiber raw materials used in the production of balancing paper are commercial pulp (such as wood and bamboo pulp) or factory-made pulp (such as wood and bamboo pulp). With the scarcity of fiber resources, pulp production costs and prices are constantly rising, leading to an increase in the production cost of balancing paper, while market demand continues to rise. Therefore, there is an urgent need to provide a balancing paper pulp that is low in production cost, meets user requirements, and does not harm the environment.

[0005] Although my country's balancing paper industry started relatively late, its high profit margins and broad market prospects have driven the rapid expansion of the entire industry. A considerable number of companies, including traditional paper manufacturers, have invested in the balancing paper industry. However, due to its high technological barriers and large capital investment, especially after years of fierce market competition and rapid industrial upgrading, most small and medium-sized balancing paper manufacturers in China have closed down or switched to other products due to high product homogeneity, low added value, unstable quality, or broken capital chains. Those that can barely maintain production can only produce low-end products. The few large-scale balancing paper manufacturers mainly compete in the mid-to-high-end market, where investment costs are high and economic benefits are low.

[0006] Therefore, it is of great significance to prepare a low-cost, high-quality anti-wrinkle balance paper with high tensile strength. Summary of the Invention

[0007] The purpose of this invention is to provide a high tensile strength anti-wrinkle balancing paper and its preparation method, so as to solve the problems mentioned in the background art.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0009] A method for preparing a high-tensile-strength, wrinkle-resistant balanced paper includes the following steps: S1: Take waste paper and filler, pulp them to a pulping concentration of 3-4%, and obtain pulped pulp; take water, retention aid, and reinforcing agent, and mix them evenly to obtain additives; add additives and dyes to the pulped pulp, beat it to a beating concentration of 3-4%, a beating degree of 30-32°SR, and a beating time of 38-42 min to obtain paper pulp; form the paper pulp to a wire density of 0.8-1% and a basis weight of 115-125 g / m². 2 The machine speed is 85-90m / min, the moisture content after the machine is 5-6%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0010] S2: Take the base paper, coat the base resin evenly on the base paper, cool and hot press to obtain anti-wrinkle balance paper.

[0011] More preferably, the waste paper includes one or more of wood pulp, white toilet paper, and newspaper; the filler includes at least one of titanium dioxide, talc, and recycled dry sludge; the retention aid is at least one of carboxymethyl cellulose or polyacrylamide; and the reinforcing agent is 2-(isopropylamino)ethanol.

[0012] Ideally, the dye is a direct lightfast dye.

[0013] In a more optimized manner, the base paper comprises the following raw materials, by weight parts: 90-110 parts waste paper, 10-15 parts water, 0.8-1.2 parts retention aid, 2.5-3 parts reinforcing agent, and 1.5-2.5 parts dye; the filler content accounts for 10-20% of the oven-dry pulp weight.

[0014] More preferably, the filler raw materials include titanium dioxide and recycled dry mud, with the amount of recycled dry mud added being 10-40% of the mass of titanium dioxide.

[0015] In a more optimized manner, the preparation of the recycled dry sludge includes the following steps: collecting papermaking sludge with a concentration of 5% (the remainder being water), performing high-consistency sludge removal using a high-consistency sludge remover to remove impurities, with a pulp inlet pressure of 0.4 MPa and a pressure difference of 1.2 MPa; adding 1% bactericide to the papermaking sludge after high-consistency sludge removal, and drying it after sterilization treatment to obtain recycled dry sludge; the bactericide includes, but is not limited to, sodium hypochlorite and chlorine dioxide.

[0016] In a more optimized manner, cationic surfactants, starch, and carboxylated polyethylene glycol are added to the base paper. The specific steps are as follows: waste paper, fillers, and cationic surfactants are taken and pulped to a pulping concentration of 3-4% to obtain pulped pulp; water, retention aids, and reinforcing agents are taken and mixed evenly to obtain additives; additives, dyes, starch, and carboxylated polyethylene glycol are added to the pulped pulp, and beating is performed to a beating concentration of 3-4%, a beating degree of 30-32°SR, and a beating time of 38-42 minutes to obtain paper pulp; the paper pulp is then formed to a paperboard concentration of 0.8-1% and a basis weight of 115-125 g / m². 2 The machine speed is 85-90m / min, the moisture content after exiting the machine is 5-6%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0017] In a more optimized manner, the base paper comprises the following raw materials, by weight parts: 90-110 parts waste paper, 10-15 parts water, 0.5-1 part cationic surfactant, 30-35 parts starch, 5-10 parts carboxylated polyethylene glycol, 0.8-1.2 parts retention aid, 2.5-3 parts reinforcing agent, and 1.5-2.5 parts dye; the filler content accounts for 10-20% of the oven-dry pulp weight.

[0018] In a more optimized manner, the preparation of the matrix resin includes the following steps: taking formaldehyde and water, mixing them evenly to obtain a formaldehyde aqueous solution; taking the formaldehyde aqueous solution, adjusting the pH to 8-9, raising the temperature to 50-60℃, adding melamine, raising the temperature to 80-90℃, reacting for 1-2 hours, adding a modifier, raising the temperature to 100-120℃, reacting for 1-2 hours, and obtaining the matrix resin.

[0019] More preferably, the formaldehyde aqueous solution comprises the following raw materials, by mass parts: 35-45 parts formaldehyde, 55-65 parts water; the matrix resin comprises the following raw materials, by mass parts: 90-110 parts formaldehyde aqueous solution, 35-45 parts melamine, 5-8 parts modifier.

[0020] In a more optimized manner, the preparation of the modifier includes the following steps, by mass parts: take polyvinyl alcohol and water, mix them evenly, heat to 85-95°C, stir until completely dissolved, add chitosan, and react at 80-90°C for 2-3 hours to obtain the modifier.

[0021] More preferably, the modifier comprises the following raw materials, by mass parts: 10-20 parts polyvinyl alcohol, 80-90 parts water, and 1-2 parts chitosan.

[0022] Compared with the prior art, the beneficial effects achieved by the present invention are: (1) Adding filler in the pulping and beating step allows the filler to fully contact the fiber and enter the cell cavity during the process of fiber cell wall destruction; at the same time, adding retention aids such as sodium carboxymethyl cellulose and anionic polyacrylamide improves the filler retention rate, and the resulting base paper is opaque, has good opacity, and high filler retention rate; by replacing titanium dioxide and talc with partially recycled dry mud, the production cost is greatly reduced and the market competitiveness is improved; the high frequency desiccant and high hammer mill are selected for series pulping, so that the fiber desiccant is thoroughly desiccanted, and after pulping, there are almost no pulp spots and fiber bundles, so that the fiber is evenly dispersed; using waste paper such as wood pulp, white toilet paper, and newspaper as raw materials saves costs and meets environmental protection requirements; the pulping process reduces time costs, and the pulping and beating process is reduced from the usual 90 minutes to 40 minutes, which is energy-saving and efficient.

[0023] (2) When preparing the base paper, cationic surfactants are added. The fillers treated with cationic surfactants are positively charged, while the retention aids carboxymethyl cellulose or polyacrylamide are negatively charged. The two generate electrostatic adsorption, which effectively prevents filler agglomeration and improves filler retention. Starch and carboxylated polyethylene glycol are also added. Starch is a natural adhesive that can improve tensile strength and paper density. Carboxylated polyethylene glycol has a high molecular weight and adhesive ability, which can form a network structure, increase tensile strength, and improve the surface smoothness of paper. At the same time, carboxylated polyethylene glycol is negatively charged and can generate electrostatic adsorption with fillers, further preventing filler agglomeration and effectively improving filler retention. The long polyethylene glycol chain can be embedded in the ring structure in the starch chain to form a riveting effect and a strong bond.

[0024] (3) A modifier was prepared using polyvinyl alcohol and chitosan as raw materials. The modifier was added during the alkaline synthesis stage of melamine-formaldehyde resin produced by the reaction of formaldehyde and melamine to obtain the matrix resin. Polyvinyl alcohol contains a large number of active hydroxyl groups on its molecular chain. It is non-toxic, odorless, and has excellent adhesion and film-forming properties. The introduction of polyvinyl alcohol can improve the friction resistance, chemical resistance, and film smoothness. At the same time, polyvinyl alcohol acts as a bridge to introduce chitosan. The network structure of chitosan can improve tensile strength, elongation strength, etc., and help to prevent wrinkles. The modifier was added during the synthesis of the matrix resin and crosslinked with melamine-formaldehyde resin under alkaline conditions, thus successfully modifying it.

[0025] (4) When the modified resin is coated on the base paper, a two-stage coating process is adopted, which makes the sizing easy to control. The amount of sizing ensures the tensile strength and anti-wrinkle ability of the balance paper, and the surface quality of the anti-wrinkle balance paper is high. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The following examples include the following raw materials: polyvinyl alcohol (model: BP-05, Jiangsu Changchun Chemical Co., Ltd.); chitosan (degree of deacetylation ≥95%, Aladdin); formaldehyde (CAS: 50-00-0); melamine (CAS: 108-78-1); titanium dioxide (model: ATR312, Dongguan Dingxin Plastic Raw Materials Co., Ltd.); cationic surfactant (dodecyl dimethyl benzyl ammonium chloride, CAS: 139-07-1); retention aid (polyacrylamide, molecular weight ~600w, Shanghai Yuanye Biotechnology Co., Ltd.); reinforcing agent (2-(isopropylamino)ethanol, CAS: 109-56-8); starch (corn starch, Xingzhongcheng food grade, 99%); carboxylated polyethylene glycol (Mw ~2000, Shanghai Yuanye Biotechnology Co., Ltd.).

[0028] The following quantities are by weight;

[0029] Example 1: S1: Take 100 parts waste paper and 15% filler (by weight of oven-dry pulp), pulp them to a pulping concentration of 3.5%, and obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, mix them evenly to obtain additives; add the additives and 1.5 parts dye to the pulped pulp, beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 minutes to obtain paper pulp; process the paper pulp to form paper, with a web fill concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after exiting the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0030] Example 2: S1: Take 100 parts waste paper, 15% filler (by weight of oven-dry pulp), and 0.8 parts cationic surfactant, and pulp them to a pulping concentration of 3.5% to obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, and mix them evenly to obtain additives; add the additives, 1.5 parts dye, 33 parts starch, and 8 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 minutes to obtain paper pulp. Form the paper pulp to a paperboard concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after exiting the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0031] Example 3: S1: Take 100 parts waste paper, 15% filler (by weight of oven-dry pulp), and 0.8 parts cationic surfactant, and pulp them to a pulping concentration of 3.5% to obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, and mix them evenly to obtain additives; add the additives, 1.5 parts dye, 33 parts starch, and 8 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 minutes to obtain paper pulp. Form the paper pulp to a paperboard concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0032] S2: Take 15 parts of polyvinyl alcohol and 85 parts of water, mix them evenly, heat to 88°C, stir until completely dissolved, add 1.5 parts of chitosan, and react at 85°C for 2 hours to obtain the modifier.

[0033] S3: Take 40 parts formaldehyde and 60 parts water, mix them evenly to obtain a formaldehyde aqueous solution; take 98 parts formaldehyde aqueous solution, adjust the pH to 8, raise the temperature to 55℃, add 42 parts melamine, raise the temperature to 82℃, react for 2 hours, add 6 parts modifier, raise the temperature to 110℃, react for 2 hours to obtain the matrix resin.

[0034] S4: Take the base paper and evenly coat it with the modified resin. The total amount of resin applied to both sides is 55g / m². 2 After cooling, a second coating is applied, with a total adhesive application amount of 45g / m² on both sides. 2 Cool, dry at 98℃ for 4 minutes, then hot press at 30N pressure and 65℃ at a speed of 5m / min. After hot pressing, wrinkle-resistant balance paper is obtained.

[0035] Example 4: S1: Take 100 parts waste paper, 15% filler (by weight of oven-dry pulp), and 0.8 parts cationic surfactant, and pulp them to a pulping concentration of 3.5% to obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, and mix them evenly to obtain additives; add the additives, 1.5 parts dye, 33 parts starch, and 10 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 minutes to obtain paper pulp. Form the paper pulp to a paperboard concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0036] S2: Take 12 parts of polyvinyl alcohol and 88 parts of water, mix them evenly, heat to 88°C, stir until completely dissolved, add 2 parts of chitosan, and react at 85°C for 2 hours to obtain the modifier.

[0037] S3: Take 40 parts formaldehyde and 60 parts water, mix them evenly to obtain a formaldehyde aqueous solution; take 95 parts formaldehyde aqueous solution, adjust the pH to 8, raise the temperature to 55℃, add 38 parts melamine, raise the temperature to 82℃, react for 2 hours, add 7 parts modifier, raise the temperature to 110℃, react for 2 hours to obtain the matrix resin.

[0038] S4: Take the base paper and evenly coat it with the modified resin. The total amount of resin applied to both sides is 65g / m². 2 After cooling, a second coating is applied, with a total adhesive application amount of 35g / m² on both sides. 2 Cool, dry at 98℃ for 4 minutes, then hot press at 30N pressure and 65℃ at a speed of 5m / min. After hot pressing, wrinkle-resistant balance paper is obtained.

[0039] Comparative Example 1 (without introducing a modifier, the remaining steps are the same as in Example 3): S1: Take 100 parts waste paper, 15% filler (by weight of oven-dry pulp), and 0.8 parts cationic surfactant, and pulp them to a pulping concentration of 3.5% to obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, and mix them evenly to obtain an additive; add the additive, 1.5 parts dye, 33 parts starch, and 8 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 min to obtain paper pulp. Form the paper pulp to a paperboard concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0040] S2: Take 40 parts formaldehyde and 60 parts water, mix them evenly to obtain a formaldehyde aqueous solution; take 98 parts formaldehyde aqueous solution, adjust the pH to 8, raise the temperature to 55℃, add 42 parts melamine, raise the temperature to 82℃, react for 2 hours, raise the temperature to 110℃, react for 2 hours, and obtain the matrix resin.

[0041] S3: Take the base paper and evenly coat it with the modified resin. The total amount of resin applied to both sides is 55g / m². 2 After cooling, a second coating is applied, with a total adhesive application amount of 45g / m² on both sides. 2 Cool, dry at 98℃ for 4 minutes, then hot press at 30N pressure and 65℃ at a speed of 5m / min. After hot pressing, wrinkle-resistant balance paper is obtained.

[0042] Comparative Example 2 (only one coating was applied during sizing; the remaining steps were the same as in Example 3): S1: Take 100 parts waste paper, 15% filler (by weight of oven-dry pulp), and 0.8 parts cationic surfactant, and pulp them to a pulping concentration of 3.5% to obtain pulped pulp; take 15 parts water, 1 part retention aid, and 2.5 parts reinforcing agent, and mix them evenly to obtain additives; add the additives, 1.5 parts dye, 33 parts starch, and 8 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3.5%, a beating degree of 30°SR, and a beating time of 40 minutes to obtain paper pulp. The paper pulp is then used for papermaking, with a web fill concentration of 1% and a basis weight of 120 g / m². 2 The machine speed is 88m / min, the moisture content after the machine is 5%, and the paper is dried, calendered, and wound up to obtain the base paper.

[0043] S2: Take 15 parts of polyvinyl alcohol and 85 parts of water, mix them evenly, heat to 88°C, stir until completely dissolved, add 1.5 parts of chitosan, and react at 85°C for 2 hours to obtain the modifier.

[0044] S3: Take 40 parts formaldehyde and 60 parts water, mix them evenly to obtain a formaldehyde aqueous solution; take 98 parts formaldehyde aqueous solution, adjust the pH to 8, raise the temperature to 55℃, add 42 parts melamine, raise the temperature to 82℃, react for 2 hours, add 6 parts modifier, raise the temperature to 110℃, react for 2 hours to obtain the matrix resin.

[0045] S4: Take the base paper and evenly coat it with the modified resin. The total amount of resin applied to both sides is 100g / m². 2 After cooling, dry at 98℃ for 4 minutes, then hot press at 30N pressure and 65℃ at a speed of 5m / min. After hot pressing, wrinkle-resistant balance paper is obtained.

[0046] Experiment: (1) Take the base paper prepared in Example 1 and Example 2, refer to GB / T12914-2018, use DC-KZ300C computer-controlled tensile testing machine to determine the tensile strength of the sample, the sample size is 15*100mm; place the sample on a 60-mesh sieve, spray water at a height of 26cm for 10min with a spray bottle, use filter paper to absorb the moisture on the surface of the paper strip, test the wet tensile strength, the test method is the same as the tensile strength method; calculate the basis weight: basis weight = sample mass / sample area; refer to GB / T1540-2002, measure the water absorption; see Table 1 for details;

[0047] Table 1:

[0048] Example 1 Example 2 <![CDATA[Quantitative / (g / m 2 )]]> 80 81 Banner basis weight difference / % 2.5 2.5 Tensile strength (longitudinal) (kN / m) 2.8 3.1 Wet tensile strength (longitudinal) (kN / m) 0.68 0.74 Water absorption (average in both directions) (mm / 10min) 33 32 pH value 7.8 7.0 Ash content / % 20 20 Moisture content upon delivery / % 6.4 6.5

[0049] (2) Take the anti-wrinkle balance paper prepared in Example 3, Example 4, Comparative Example 1 and Comparative Example 2, and test the longitudinal tensile strength and wet tensile strength of the samples with reference to standard GB / T12914-2018; the specific conclusions are shown in Table 2.

[0050] Table 2:

[0051]

[0052] Conclusion: As shown in Table 1, the base paper prepared in the examples has good tensile strength, small basis weight difference across the width, and good water absorption. As shown in Table 2, high-quality anti-wrinkle balanced paper with good tensile strength can be prepared using matrix resin and base paper.

[0053] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0054] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a high-tensile-strength, wrinkle-resistant balancing paper, characterized in that: Includes the following steps: S1: By weight, take 90-100 parts waste paper, 10-20% filler (by oven-dry pulp weight), and 0.5-1 part cationic surfactant, and pulp them to a pulping concentration of 3-4% to obtain pulped pulp; take 10-15 parts water, 0.8-1.2 parts retention aid, and 2.5-3 parts reinforcing agent, and mix them evenly to obtain additives; add additives, 1.5-2.5 parts dye, 30-35 parts starch, and 5-10 parts carboxylated polyethylene glycol to the pulped pulp, and beat them to a beating concentration of 3-4%, a beating degree of 30-32°SR, and a beating time of 38-42 minutes to obtain paper pulp; process the paper pulp to form paper, with a web concentration of 0.8-1% and a basis weight of 115-125 g / m³. 2 The machine speed is 85-90m / min, the moisture content after the machine is 5-6%, and the paper is dried, calendered, and wound up to obtain the base paper. S2: Take the base paper, coat the base resin evenly on the base paper through a secondary coating process, cool and hot press to obtain anti-wrinkle balance paper. The waste paper includes one or more of wood pulp, white toilet paper, and newspaper; the filler includes at least one of titanium dioxide, talc, and recycled dried sludge; the retention aid is at least one of carboxymethyl cellulose or polyacrylamide; and the reinforcing agent is 2-(isopropylamino)ethanol. The preparation of the matrix resin includes the following steps: by mass, take 35-45 parts of formaldehyde and 55-65 parts of water, mix them evenly to obtain a formaldehyde aqueous solution; take 90-110 parts of the formaldehyde aqueous solution, adjust the pH to 8-9, raise the temperature to 50-60℃, add 35-45 parts of melamine, raise the temperature to 80-90℃, react for 1-2 hours, add 5-8 parts of modifier, raise the temperature to 100-120℃, react for 1-2 hours, and obtain the matrix resin; The preparation of the modifier includes the following steps: by mass, take 10-20 parts of polyvinyl alcohol and 80-90 parts of water, mix them evenly, heat to 85-95°C, stir until completely dissolved, add 1-2 parts of chitosan, and react at 80-90°C for 2-3 hours to obtain the modifier.

2. The anti-wrinkle balance paper obtained by the preparation method of the high tensile strength anti-wrinkle balance paper according to claim 1.

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