阅读说明：本技术 一种负离子静电除尘纸及其制备方法 (Negative ion electrostatic dust removal paper and preparation method thereof ) 是由 赵传山 陈立栋 李杰华 李辉 黄秋美 杜鹏 于 2020-06-19 设计创作，主要内容包括：发明涉及一种负离子静电除尘纸及其制备方法。一种负离子静电除尘纸,包括原纸层和覆盖于原纸层表面的涂布层组成,所述涂布层由涂层液涂布烘干而成。本发明将无机驻极材料和聚合物驻极材料搭配使用,制得能够满足涂布需求的涂层液,将该涂布液涂布于原纸表面制得的负离子静电除尘纸,不仅驻极效率更好,而且感应静电压更高,静电吸附能力更强,除尘效率更高。(The invention relates to negative ion electrostatic dust removal paper and a preparation method thereof. The negative ion electrostatic dust removal paper comprises a base paper layer and a coating layer covering the surface of the base paper layer, wherein the coating layer is formed by coating and drying a coating liquid. According to the invention, the inorganic electret material and the polymer electret material are matched for use to prepare the coating liquid capable of meeting the coating requirement, and the coating liquid is coated on the surface of the base paper to prepare the negative ion electrostatic dust removal paper, so that the electret efficiency is better, the induced electrostatic voltage is higher, the electrostatic adsorption capacity is stronger, and the dust removal efficiency is higher.)

1. The coating liquid is characterized by comprising the following components in parts by weight:

40-60 parts of an inorganic electret, 20-40 parts of a polymer electret, 20-40 parts of an adhesive, 0.2-0.6 part of a dispersing agent, 10-20 parts of a bacteriostatic agent, 0.3-0.8 part of a defoaming agent and 1000-1400 parts of a solvent.

2. The coating solution according to claim 1, wherein the inorganic electret is silica and/or tourmaline; further preferably, the silica is fumed silica; more preferably, the particle size of the inorganic electret is less than or equal to 500 nm.

3. The coating solution of claim 1, wherein the polymer electret is polytetrafluoroethylene powder and/or polylactic acid powder; more preferably, the polymer electret has a particle size of 2 μm or less.

4. The coating solution of claim 1, wherein the adhesive is one or a combination of two or more of polyvinyl alcohol, styrene-butadiene latex or acrylic resin; further preferably, the polyvinyl alcohol has the following indexes: the polymerization degree is 1700-2000, and the alcoholysis degree is 88-99%; more preferably, the molar ratio of butadiene to styrene in the styrene-butadiene latex is 60: 40.

5. The coating solution of claim 1, wherein the dispersant is sodium polyacrylate and/or sodium hexametaphosphate.

6. The coating solution of claim 1, wherein the bacteriostatic agent is organic antibacterial agent chitosan and/or inorganic antibacterial agent modified barium sulfate;

further preferably, the deacetylation degree of the chitosan is more than or equal to 80 percent; more preferably, the particle size of the inorganic antibacterial agent modified barium sulfate is less than or equal to 500 nm.

7. The coating solution of claim 1, wherein the defoaming agent is a silicone defoaming agent.

8. The coating solution of claim 1, wherein the solvent is selected from water and/or ethanol.

9. The coating solution according to any one of claims 1 to 8, wherein the coating solution has a solid content of 6% to 10%.

10. The method for preparing the coating liquid according to any one of claims 1 to 9, characterized by comprising the following steps:

firstly adding 40-60 parts by weight of inorganic electret and 20-40 parts by weight of polymer electret into 1000-1400 parts by weight of solvent, and firstly adding 0.2-0.6 part by weight of dispersant, and carrying out primary dispersion until the mixture is uniform; and then sequentially adding 20-40 parts by weight of adhesive, 10-20 parts by weight of bacteriostatic agent and 0.3-0.8 part by weight of defoaming agent, and dispersing for the second time until the mixture is uniform to obtain the coating liquid.

11. The method according to claim 10, wherein the primary dispersion is a high-speed dispersion for 25 to 35 minutes under a dispersion condition of a high-speed disperser of 1000 to 3000 r/min.

12. The method according to claim 10, wherein the secondary dispersion is a dispersion in a high speed disperser at 1000 to 3000r/min for 15 to 25 minutes.

13. An anion electrostatic dust removal paper, which is characterized by comprising a base paper layer and a coating layer covered on the surface of the base paper layer, wherein the coating layer is formed by coating and drying the coating liquid of any one of claims 1 to 9.

14. The negative ion electrostatic precipitator paper of claim 13, wherein the base paper layer is comprised of base paper, and the physical properties of the base paper layer are as follows: quantification: 40-80 g per square meter, tensile strength: 4 KN/m-8 KN/m; wet strength: 10 to 20 percent.

15. The negative ion electrostatic precipitator paper of claim 14, wherein the negative ion electrostatic precipitator paper has an induced electrostatic voltage of 600-1500V and a negative ion release amount of 3000 negative ion/cm³5000 pieces/cm³。

16. The preparation method of the negative ion electrostatic dust removal paper is characterized by comprising the following steps:

(1) feeding a wet paper web with the quantitative of 40-80 g per square meter into a glue application part on the surface of a paper machine to coat the coating liquid according to any one of claims 1-9 on two sides, and then carrying out secondary drying and press polishing to obtain dried coated paper;

(2) and (3) performing electret on the dried coated paper prepared in the step (1) for 30-60 seconds by using electrostatic electret equipment, wherein the electret voltage is 30-60 KV, and coiling to obtain the coated paper.

17. The method according to claim 16, wherein in the step (1), the coating liquid is applied in an amount of 4 to 6g/m in terms of solid content²。

18. The method of claim 16, wherein in the step (1), the coating is one of blade coating, air knife coating, and film transfer coating.

Technical Field

The invention relates to negative ion electrostatic dust removal paper and a preparation method thereof, in particular to negative ion electrostatic dust removal paper with large electrostatic voltage, good dust absorption and large negative ion release amount and a preparation method thereof, belonging to the technical field of papermaking.

Background

Along with the development of society, the physical living standard and the civilization degree of people are continuously improved. People have higher and higher requirements on life quality, and also have higher requirements on the cleanness of the environment, instruments and equipment and families, in particular to the industries of electronics, precision machinery, aerospace, aviation, hospitals and the like. However, with the rapid development of the Chinese industrial technology, environmental pollution has become the most serious problem facing China. A proper amount of dust in the air has certain benefits to the environment, but the excessive amount of dust in urban environment seriously harms the environment and the healthy life of people. The excessive dust is easy to breed bacteria and viruses, which is extremely unfavorable for the health of the human body and has great harm to the health of the skin. Dust-removing paper having excellent properties is required. Such as: no dust, adsorbability and cleaning property, and can effectively remove dust, oil stain and fingerprints without damaging the surface of the wiped object. The electrostatic dust-removing paper is a special fiber material which is widely applied in production and life, and is special paper or non-woven fabric made of plant fibers or organic fibers. When the paper cleaning machine is used, paper generates static electricity in a friction electrification mode, and fine substances such as dust and scurf are adsorbed by the electrostatic adsorption principle, so that the dust is eliminated, and the environment is purified.

Chinese patent document CN 208928752U discloses an electrostatic precipitator paper, which includes a spun-laced nonwoven fabric, an electrostatic adhesive coating with adsorptivity and a sticky paper layer, wherein the electrostatic adhesive coating is disposed on one side end face of the spun-laced nonwoven fabric, and the paper layer is disposed on the other side end face of the spun-laced nonwoven fabric. This scheme has solved electrostatic precipitator paper and can't clear away paper granule, cloth matter granule and large granule dust, influences dust removal effect's technical problem. According to the scheme, the main body of the electrostatic dust removal paper is spunlace non-woven fabric, and is not easy to decompose and causes pollution to the environment.

Chinese patent document CN 103850150A (application No. 201410117281.9) discloses a papermaking process of industrial dust-free wiping paper, which comprises wood pulp disintegration, desanding, pulping, pulp mixing, screening and purifying, net-feeding forming, centrifugal dewatering, squeezing dewatering, drying and scraper wrinkling of a drying cylinder, reeling, rewinding, slitting and packaging to obtain a finished product, wherein the wood pulp disintegration is to disintegrate fibers of long fiber wood pulp with the fiber length of 2.5-2.7 mm and short fiber wood pulp with the fiber length of 0.7-0.9 mm according to the weight ratio of 90-95: 10-5, a biopolymer with the concentration of 25-30% and the ton paper usage of 10-12 kg is added during pulp mixing, a wet strength agent with the concentration of 20-30% is added to fibers after pulp mixing before net-feeding forming, and the ton paper usage is 50-70 kg. The scheme has the advantages of high wet tensile strength, small particle emission rate, small dust generation amount and small ion precipitation. The dust-free wiping paper prepared by the scheme has small dust amount, but can gather dust together, so that the dust is not easy to wipe clean, and the wiped dust is easy to shake off and pollute other places.

Chinese patent document CN 109023942 a discloses a method for preparing an antibacterial polypropylene nonwoven fabric for wiping paper, comprising: adding graphene oxide into dimethyl acetamide for dispersion, adding mercaptosuccinic acid and anhydrous triethylamine for reaction, and performing aftertreatment to obtain a material A; adding the material A into dimethylacetamide for dispersion, adding curcumin and p-toluenesulfonic acid for reaction, and performing aftertreatment to obtain modified graphene oxide; mixing sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, sodium phosphate, modified graphene oxide, carbon nanotube, nano silver, aloe extract and water to obtain a maceration extract; dipping the polypropylene non-woven fabric in the dipping solution, and drying to obtain dipped non-woven fabric; adding 5, 5-dimethyl hydantoin into a sodium hydroxide aqueous solution, adding methanol, adding allyl bromide, and reacting to obtain a hydantoin derivative; mixing acrylic resin, hydroxyethyl acrylate, octadecyl acrylate, hydantoin derivative, photoinitiator and ethyl acetate, adding impregnated non-woven fabric, soaking, drying, curing, chlorinating, washing and drying. The method has mild conditions, and the obtained non-woven fabric has good antibacterial property and strong water absorption. The polypropylene non-woven fabric used by the scheme is difficult to decompose, not only wastes resources, but also causes great pollution to the environment. And the molecular chain of the polypropylene material has a large amount of tertiary carbon atoms due to the characteristics of the molecular structure, and the atoms can be aged and degraded to different degrees under the action of light, oxygen and heat, so that short carbon chains are generated, and the short carbon chains can release volatile substances of aldehydes and ketones after being oxidized, thereby causing damage to human bodies.

Korean patent document KR1020010081333A (application No. KR1020000006689) discloses a method of manufacturing a high-efficiency electrostatic filter medium which is provided to improve the collection efficiency of fine particles and the variation and time for the reduction of the collection efficiency are long for long-term use. The composition is that organic or inorganic fine particles are attached to an insulating electrostatic fiber sheet, and the electrostatic fiber sheet is charged. The electrostatic fibers used for insulation are organic or inorganic fibers, and the organic fibers may be polypropylene, polyethylene, poly-3-methyl-butene, polytetramethyl-pentene, polyvinylidene fluoride, polytetrafluoroethylene, polycarbonate, polystyrene, polyvinylidene chloride, polyvinyl chloride, polyethylene terephthalate, polyamide, polyacrylonitrile, polysulfone or polyphenylene oxide. The inorganic fiber is polysilicate glass or silica glass.

Disclosure of Invention

Aiming at the problems of low dust removal effect, high cost, environmental pollution, harm to human bodies and the like, the invention provides the manufacturing method of the electrostatic dust removal paper with simple operation and moderate cost, which is used for manufacturing the negative ion electrostatic dust removal paper with excellent quality, large electrostatic voltage, good dust absorption and large negative ion release amount.

The technical scheme of the invention is as follows:

the coating liquid comprises the following components in parts by weight:

40-60 parts of an inorganic electret, 20-40 parts of a polymer electret, 20-40 parts of an adhesive, 0.2-0.6 part of a dispersing agent, 10-20 parts of a bacteriostatic agent, 0.3-0.8 part of a defoaming agent and 1000-1400 parts of a solvent.

The electret is a dielectric material with a long-term charge storage function, and the stored charge can be externally injected unipolar real charge (or space charge), can also be dipole charge formed by orderly orientation of dipoles in a polar dielectric, or can be both of the two types of charge. The electret material can increase the electrostatic adsorption capacity of the material, and can directly absorb the charged particles in the gas phase and capture the charged particles by means of coulomb force or induce the neutral particles to generate polarity and capture the neutral particles, so that the submicron particles in the gas carrier phase can be more effectively adsorbed, and the adsorption dust removal efficiency is greatly enhanced. The invention uses the inorganic electret material and the polymer electret material together, so the electret efficiency is better and the dust removal efficiency is higher.

Preferably according to the invention, the inorganic electret is silica and/or tourmaline. Further preferably, the silica is fumed silica. Because the fumed silica has extremely high specific surface area, the larger the specific surface area of the dedusting paper is, and the stronger the dedusting capability is. Among known electret minerals with permanent polarity, tourmaline has the strongest permanent self-generating polarity, and water vapor in the air can form thick OH with antibacterial effect on the surfaces of metal oxides^-A surface layer. Moreover, the tourmaline also has the functions of releasing negative ions, radiating far infrared rays, resisting bacteria, deodorizing and the like, which is beneficial to human beings and the environment. The negative ions can regulate the ionic balance of the human body, activate cells, inhibit bacterial infection, improve the self-healing capacity of the human body, adsorb dust in the air and purify the air.

More preferably, the particle size of the inorganic electret is less than or equal to 500 nm. The proper particle size is helpful for increasing the surface area of the inorganic electret and increasing the electret effect.

Preferably according to the invention, the polymer electret is polytetrafluoroethylene powder and/or polylactic acid powder. The polytetrafluoroethylene is an important organic fluorocarbon polymer, has the characteristics of dielectricity, low dielectric loss, high breakdown voltage, high volume resistivity and the like, and presents the most excellent space charge storage stability and biocompatibility. The polylactic acid not only has the characteristics of a nonpolar high polymer, but also is a polymer with excellent performance, biocompatibility, bacteriostasis and degradability.

More preferably, the polymer electret has a particle size of 2 μm or less.

Generally speaking, the electret effect can be increased by increasing the addition amount of the electret, but the addition amount of the electret can also cause hair and powder falling on the surface of the negative ion electrostatic dust removal paper. The inventor tries various materials and different proportions through a large number of experiments, and finds that the inorganic electret and the polymer electret are added together, and have a synergistic interaction effect mutually, so that the surface electrostatic voltage of the negative ion electrostatic dust removal paper can be well improved, and the dust removal effect is improved.

According to the invention, the adhesive is preferably one or a combination of more than two of polyvinyl alcohol, styrene-butadiene latex or acrylic resin. Further preferably, the polyvinyl alcohol has the following indexes: the polymerization degree is 1700-2000, and the alcoholysis degree is 88-99%; the molar ratio of butadiene to styrene in the styrene-butadiene latex is 60: 40.

Preferably, according to the invention, the dispersant is sodium polyacrylate and/or sodium hexametaphosphate. The dispersion mechanism of sodium hexametaphosphate is to ionize PO in solution by sodium hexametaphosphate^3-And then adsorbed on the surface of the particles in a large amount to form an electric double layer structure. The mechanism of sodium polyacrylate dispersion is to disperse the particles in the solution more stably by the action of electro-steric stabilization. The viscosity of the sodium polyacrylate is very high when the sodium polyacrylate is dissolved in water, one end of a long polymer chain of the sodium polyacrylate is adsorbed on the surface of the particles to block the violent movement of pigment particles, and the sodium polyacrylate can ionize anions to form an electric double layer between the particles.

According to the invention, the bacteriostatic agent is organic antibacterial agent chitosan and/or inorganic antibacterial agent modified barium sulfate. Chitosan is a cationic polysaccharide obtained by deacetylating chitin under the action of strong alkali, can be compatible with organisms, is commonly used as a carrier for substances such as enzymes, antigens, antibodies and the like, and even can excite the action of beneficial enzymes and inhibit the action of harmful enzymes.

Further preferably, the deacetylation degree of chitosan is not less than 80%. The inorganic antibacterial agent modified barium sulfate takes inorganic barium sulfate as an antibacterial agent carrier, and silver phosphate is coated on the inorganic barium sulfate by modification. More preferably, the particle size of the inorganic antibacterial agent modified barium sulfate is less than or equal to 500 nm.

Preferably, according to the invention, the defoamer is a silicone defoamer. The antifoaming agent is a substance capable of reducing the surface tension of water, solutions, suspensions, etc., preventing the formation of foam, or reducing or eliminating the original foam.

According to the invention, the solid content of the coating liquid is preferably 6% to 10%.

Preferably according to the invention, the solvent is selected from water and/or ethanol.

The invention also provides a using method of the coating liquid, the coating liquid is applied to a sizing system of a paper machine, and the coating weight is 4-6 g/m in terms of solid content². The electrostatic dust removal paper can be formed in one step in the paper machine, the process is simple, and the production is efficient.

The invention also provides a preparation method of the coating liquid, which comprises the following specific steps:

firstly adding 40-60 parts by weight of inorganic electret and 20-40 parts by weight of polymer electret into 1000-1400 parts by weight of solvent, and firstly adding 0.2-0.6 part by weight of dispersant, and carrying out primary dispersion until the mixture is uniform; and then sequentially adding 20-40 parts by weight of adhesive, 10-20 parts by weight of bacteriostatic agent and 0.3-0.8 part by weight of defoaming agent, and dispersing for the second time until the mixture is uniform to obtain the coating liquid.

According to the invention, the first dispersion is preferably carried out for 25-35 minutes at a high speed under the dispersion condition of a high-speed dispersion machine of 1000-3000 r/min.

According to the invention, the secondary dispersion is preferably carried out for 15-25 minutes under the dispersion condition of a high-speed dispersion machine of 1000-3000 r/min.

It should be noted that the coating liquid of the present invention is a whole, and although each component has its own function, these components are used as a whole to form the coating liquid together, and through specific steps and addition sequence, and mixed well under specific dispersion conditions, form a stable, moderate viscosity and easy-to-apply coating liquid; after the electret, the charge can be stored, so that the charge decay of the filter material is slowly slowed down, and the service time is prolonged.

The invention also provides negative ion electrostatic dust removal paper which comprises a base paper layer and a coating layer covering the surface of the base paper layer, wherein the coating layer is formed by coating and drying the coating liquid.

Preferably, according to the invention, the raw paper layer consists of base paper, and the physical properties of the raw paper layer are as follows: quantification: 40 to 80g/m²The tensile strength: 4 KN/m-8 KN/m; wet strength: 10 to 20 percent.

According to the invention, the preferable negative ion electrostatic dust removal paper has the induction static voltage of 600-1500V and the negative ion release amount of 3000 negative ions/cm³5000 pieces/cm³。

The invention also provides a preparation method of the negative ion electrostatic dust removal paper, which comprises the following steps:

(1) the quantitative ratio is 40-80 g/m²The wet paper web is sent to a gluing part on the surface of a paper machine to carry out double-sided coating of the coating liquid, and then secondary drying and press polishing are carried out to prepare dried coated paper;

(2) and (3) performing electret on the dried coated paper prepared in the step (1) for 30-60 seconds by using electrostatic electret equipment, wherein the electret voltage is 30-60 KV, and coiling to obtain the coated paper.

According to the invention, in the step (1), the coating weight of the coating liquid is 4-6 g/m in terms of solid content²。

Preferably, in the step (1), the coating is performed by one of blade coating, air knife coating and film transfer coating.

The secondary drying and calendering in the step (1) are conventional techniques in the field. The solid content is the mass of the components in the coating liquid after the solvent is removed.

Advantageous effects

1. According to the invention, the inorganic electret material and the polymer electret material are matched for use to prepare the coating liquid capable of meeting the coating requirement, and the coating liquid is coated on the surface of the base paper to prepare the negative ion electrostatic dust removal paper, so that the electret efficiency is better, the induced electrostatic voltage is higher, the electrostatic adsorption capacity is stronger, and the dust removal efficiency is higher;

2. the tourmaline in the coating liquid not only has the functions of releasing negative ions, radiating far infrared rays, resisting bacteria, deodorizing and the like; moreover, the induced static voltage can be improved, and the technical effect of the electret material is promoted; the dust-absorbing paper can not only realize the dust-absorbing function of common electrostatic dust-removing paper, but also adjust the ion balance of human body by negative ions, activate cells, inhibit fungus infection, improve the self-healing capability of human body and purify air.

Detailed description of the invention

The technical solution of the present invention is further described with reference to the following examples, but the scope of the present invention is not limited thereto.

Source of raw materials