Papermaking method added with plant ash and bactericidal herbaceous plants and paper
By adding wood ash and bactericidal herbal extracts during the papermaking process, paper with natural antibacterial properties is prepared, which solves the problem of paper's lack of antibacterial properties and environmental friendliness during use, and achieves environmentally friendly and efficient paper production.
Patent Information
- Application Number
- CN202511110316.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-08
- Publication Date
- 2025-09-19
AI Technical Summary
Existing paper lacks natural antibacterial properties during use and is not environmentally friendly, making it difficult to meet high-quality and environmentally friendly requirements.
Wood ash and extracts of bactericidal herbs are used as additives, and through grinding, screening and concentration, pulp with antibacterial properties is prepared, which is then combined with traditional papermaking technology to produce paper.
The prepared paper has long-lasting antibacterial properties, reduces environmental pollution, improves the durability and opacity of the paper, is suitable for a variety of uses, is cost-effective, and is suitable for resource recycling.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of paper production, and relates to a papermaking method and paper with wood ash and sterilized herbs added. Background Art
[0002] Paper is a thin sheet material made from plant fibers (such as wood, bamboo, and cotton) through physical and chemical processing. It is used for writing, printing, packaging, cleaning, and many other purposes. Paper has good water absorption, writability, and printability. It is also an environmentally friendly material that can be recycled.
[0003] Papermaking is the process and technology of converting plant fiber materials (such as wood, bamboo, and cotton) into paper through a series of physical and chemical processing steps. Modern papermaking technology combines advanced mechanical, chemical, and automated control methods to greatly improve production efficiency and product quality.
[0004] Most of the current paper is manufactured to cope with daily life. However, with the improvement of the quality of life, the cleanliness of the environment and the quality of paper have also improved. For paper used close to the body, it needs to be comfortable and safe, while for paper that needs to be stored, it needs to have storage-resistant insect and antiseptic properties. To this end, the inventors have proposed a papermaking method and paper with the addition of wood ash and sterilizing herbs to solve the above-mentioned technical problems. Summary of the Invention
[0005] In order to overcome the above-mentioned shortcomings, the present invention aims to provide a technical solution that can solve the above-mentioned problems.
[0006] A papermaking method with the addition of wood ash and sterilized herbs, comprising: (1) Ash pretreatment: Grind the dried ash and sieve it to obtain ash powder with uniform particle size; Source of raw materials: Wood ash can be derived from the ashes of burning plants such as rice straw, wheat straw, bamboo leaves, and fruit tree branches and leaves. It is a natural plant combustion product that is pollution-free and free of heavy metal residues. The collected wood ash is first passed through a 100-mesh sieve to initially remove large particles of impurities, and then finely ground using a ball mill or airflow mill to ensure uniform particles. Screening uses a standard sieve of 100 to 200 mesh to obtain fine powder with a particle size of 75 to 149 μm. Wood ash is rich in minerals such as potassium, calcium, magnesium, and silicon, and is weakly alkaline with an alkaline pH range of 9 to 11, which helps to improve the alkaline sizing effect of paper and enhance the durability and anti-aging ability of paper. Its fine particles can also fill the gaps between fibers and improve the smoothness and opacity of paper. (2) Preparation of bactericidal herbal extracts: Select herbal plants with bactericidal effects, wash and chop them, and then use water or alcohol extraction to obtain an extract, which is then concentrated to obtain a concentrated extract; Artemisia annua contains eucalyptol and thujone; honeysuckle contains chlorogenic acid and luteolin; coptis root contains berberine; perilla contains perilla aldehyde; and mint contains menthol. These herbal plants have broad-spectrum antibacterial and antiviral properties. The chopped herbs are mixed with deionized water in a mass ratio of 1:8 to 1:12, extracted in an 80°C constant temperature water bath for 2 hours, and the extraction is repeated twice. The filtrates are combined; then, a 50% ethanol solution is used with a solid-liquid ratio of 1:10, and reflux extraction is carried out at 65°C for 1.5 hours. After filtration, the ethanol is recovered and concentrated to 1 / 3 of the original volume. The extract is subjected to vacuum rotary evaporation at an evaporation temperature of ≤60°C to avoid decomposition of heat-sensitive components. The extract is concentrated to a solid content of 25% to 35%, vitamin E is added as a natural preservative, and then refrigerated for storage. (3) Pulping: The fiber raw materials for papermaking are subjected to conventional beating treatment to obtain pulp; (4) Adding and mixing: adding the wood ash powder obtained in step (1) and the concentrated extract obtained in step (2) to the pulp obtained in step (3), stirring and mixing them uniformly to form a mixed pulp containing wood ash and the bactericidal component; The beating degree of the pulp is controlled within the range of 30-45°SR (Schober's degree) to ensure good fiber bonding and paper strength. After beating, the pulp is diluted to 3%-4% for subsequent mixing to facilitate uniform dispersion of additives. First, sprinkle the wood ash powder evenly into the pulp and stir for 5 to 10 minutes to fully disperse it; then slowly add the concentrated extract and continue stirring for 10 to 15 minutes to avoid local excessive concentration leading to flocculation. The addition amount is controlled as follows: Wood ash: 3% to 8% of the absolute dry fiber mass to avoid excessive concentration affecting the strength and color of the paper. Concentrated extract: Based on the effective antibacterial component, the addition amount is 0.3% to 1.5% to ensure the antibacterial effect without affecting the physical properties of the paper. Finally, use a high shear mixer or disc grinder to assist in dispersion to ensure that the wood ash and extract are evenly distributed in the pulp; (5) Papermaking: The mixed pulp obtained in step (4) is subjected to papermaking, pressing, and drying to obtain paper containing wood ash and sterilizing herbal plant components. The specific steps are as follows: Papermaking: A fourdrinier papermaking machine is used, with a pulp concentration of 2.5% to 3.5%, and wet paper sheets are formed through vacuum dehydration; Pressing: Multi-roller pressing and dehydration are used, with the pressure controlled at 0.3 to 0.6 MPa to increase the paper density; Drying: After entering the drying cylinder drying section, the temperature gradient is set to: 80 to 90°C in the front section, 100 to 110°C in the middle section, and 90 to 100°C in the final section. The total drying time is controlled at 3 to 5 minutes to avoid inactivation of herbal active ingredients due to high temperature; Post-treatment: Calendering is performed to improve the gloss and smoothness of the paper surface.
[0007] Furthermore, in step (1), the particle size of the wood ash is 80 mesh to 200 mesh.
[0008] Furthermore, in step (2), the herbal plants with bactericidal efficacy are selected from one or more of mugwort, honeysuckle, coptis chinensis, isatis root, perilla, and mint.
[0009] Furthermore, in step (2), the water extraction method is: mixing the chopped herb with water in a mass ratio of 1:5 to 1:15, and extracting at 60°C to 90°C for 1 to 3 hours; the alcohol extraction method is: using an ethanol solution with a concentration of 30% to 70%, and extracting at 50°C to 80°C for 1 to 2 hours.
[0010] Furthermore, in step (2), the solid content of the concentrated extract is 20% to 40%.
[0011] Furthermore, in step (4), the amount of wood ash powder added is 1% to 10% of the absolute dry mass of the fiber raw material for papermaking, and the amount of concentrated extract added is 0.1% to 2% of the absolute dry mass of the fiber raw material for papermaking, calculated based on the effective bactericidal components therein.
[0012] Furthermore, in the step (4), the concentration of the pulp during mixing is 2% to 5%.
[0013] Furthermore, in the step (5), the drying temperature is 80°C to 120°C.
[0014] A type of paper produced by the papermaking process.
[0015] Furthermore, the paper has antibacterial properties, and the antibacterial rates against Escherichia coli and Staphylococcus aureus are not less than 70%.
[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. It has natural antibacterial function. The obtained paper has long-lasting antibacterial performance. The inhibition rate of common bacteria such as Escherichia coli, Staphylococcus aureus, and mold can reach more than 75%. It is suitable for sanitary paper, packaging paper, book paper, etc., extending the service life of paper and preventing mildew; 2. Environmentally friendly and sustainable. Wood ash is a resource utilization of agricultural waste, reducing incineration pollution. Herbs are renewable resources, replacing chemical antibacterial agents such as triclosan and quaternary ammonium salts, reducing environmental pollution and human health risks. 3. Improve paper performance. The minerals in wood ash can increase the ash content and alkaline reserve of paper, enhance durability, and are suitable for archival paper, calligraphy and painting paper, and other papers that need to be preserved for a long time. 4. Improve the opacity and light-shielding properties of paper, and are suitable for printing paper and packaging paper. Trace minerals can improve the combustion performance of paper. 5. Highly cost-effective, with a wide range of raw materials and low cost, it is suitable for resource recycling projects and promotes a green circular economy. Moreover, this method can be modified on the basis of existing papermaking technology without the need for major equipment investment, and can be promoted in light industrialization. DETAILED DESCRIPTION
[0017] The present invention is described in further detail below in conjunction with specific embodiments.
[0018] In this embodiment, please refer to a specific implementation of a papermaking method that adds wood ash and sterilized herbs, including: (1) Ash pretreatment: Grind the dried ash and sieve it to obtain ash powder with uniform particle size; Source of raw materials: Wood ash can be derived from the ashes of burned plants such as rice straw, wheat straw, bamboo leaves, and fruit tree branches and leaves. It is a natural plant combustion product that is pollution-free and free of heavy metal residues. The collected wood ash is first screened through a 100-mesh sieve to remove large particles of impurities, and then finely ground using a ball mill or airflow mill to ensure uniform particles. A 115-mesh standard sieve is used for screening to obtain fine powder with a particle size of 95μm. Wood ash is rich in minerals such as potassium, calcium, magnesium, and silicon, and is weakly alkaline with an alkaline pH in the range of 10, which helps to improve the alkaline sizing effect of paper and enhance the durability and anti-aging ability of paper. Its fine particles can also fill the gaps between fibers, improving the smoothness and opacity of paper. (2) Preparation of bactericidal herbal extracts: Select herbal plants with bactericidal effects, wash and chop them, and then use water or alcohol extraction to obtain an extract, which is then concentrated to obtain a concentrated extract; Artemisia annua contains eucalyptol and thujone; honeysuckle contains chlorogenic acid and luteolin; coptis root contains berberine; perilla contains perilla aldehyde; and mint contains menthol. These herbal plants have broad-spectrum antibacterial and antiviral properties. The chopped herb is mixed with deionized water in a mass ratio of 1:10, extracted in an 80°C constant temperature water bath for 2 hours, and the extraction is repeated twice. The filtrates are combined; then, a 50% ethanol solution is used with a solid-liquid ratio of 1:10, and reflux extraction is carried out at 65°C for 1.5 hours. After filtration, the ethanol is recovered and concentrated to 1 / 3 of the original volume. The extract is subjected to vacuum rotary evaporation at an evaporation temperature of ≤60°C to avoid decomposition of heat-sensitive components. After concentration to a solid content of 30%, vitamin E is added as a natural preservative, and then refrigerated for storage. (3) Pulping: The fiber raw materials for papermaking are subjected to conventional beating treatment to obtain pulp; (4) Adding and mixing: adding the wood ash powder obtained in step (1) and the concentrated extract obtained in step (2) to the pulp obtained in step (3), stirring and mixing them uniformly to form a mixed pulp containing wood ash and the bactericidal component; The beating degree of the pulp is controlled within the range of 41°SR (Schober's degree) to ensure good fiber bonding and paper strength. After beating, it is diluted to 3% for subsequent mixing to facilitate uniform dispersion of additives. First, sprinkle the wood ash powder evenly into the pulp and stir for 7 minutes to fully disperse it; then slowly add the concentrated extract and continue stirring for 10 minutes to avoid local excessive concentration leading to flocculation. The addition amount is controlled as follows: Wood ash: 4%, 5% or 7% of the absolute dry fiber mass to avoid excessive concentration affecting the strength and color of the paper. Concentrated extract: Based on the effective antibacterial component, the addition amount is 0.4%, 1% or 1.3% to ensure the antibacterial effect without affecting the physical properties of the paper. Finally, use a high shear mixer or disc grinder to assist in dispersion to ensure that the wood ash and extract are evenly distributed in the pulp; (5) Papermaking: The mixed pulp obtained in step (4) is subjected to papermaking, pressing, and drying to obtain paper containing wood ash and sterilizing herbal plant components. The specific steps are as follows: Papermaking: A Fourdrinier papermaking machine is used, with a pulp concentration of 3% on the web, and wet paper sheets are formed through vacuum dehydration; Pressing: A multi-roller press is used for dehydration, with the pressure controlled at 0.4 MPa to increase the paper density; Drying: After entering the drying cylinder drying section, the temperature gradient is set to: 85°C in the front section, 1007°C in the middle section, and 90°C in the final section. The total drying time is controlled at 5 minutes to avoid inactivation of herbal active ingredients due to high temperature; Post-treatment: Calendering is performed to improve the gloss and smoothness of the paper surface.
[0019] In the step (1), the particle size of the wood ash is 100 mesh, and the converted particle size is about 149 microns. The particle size of the 100 mesh wood ash powder is moderate, neither too large nor too fine, and is easy to be evenly dispersed in the paper pulp, and is not easy to agglomerate or precipitate. It effectively prevents the formation of "dust spots" or "spots" due to particle aggregation during the papermaking process, avoids the generation of holes and weak points in strength, and improves the appearance quality and physical uniformity of the paper. The moderate particle size can form good mechanical interlocking and surface adsorption with plant fibers, which helps to improve the retention rate of wood ash in the paper sheet, reduce the loss during the dehydration process of the mesh, and improve the utilization rate of raw materials; at the same time, it strengthens the combination between the filler and the fiber, and has less negative impact on the tensile strength and bursting resistance.
[0020] In the step (2), the herbal plants with bactericidal efficacy are selected from one or more of mugwort, honeysuckle, coptis root, isatis root, perilla, and mint. Mugwort contains eucalyptol and thujone; honeysuckle contains chlorogenic acid and luteolin; coptis root contains berberine; perilla contains perillaldehyde; and mint contains menthol. The herbal plants have broad-spectrum antibacterial and antiviral properties, are natural additives, do not require chemical ingredients, and increase paper safety. Paper manufactured using the natural additives can come into contact with the skin.
[0021] In step (2), the water extraction method is: mixing the chopped herb with water in a mass ratio of 1:3 to 1:10, and extracting at 85°C for 2 hours; the alcohol extraction method is: using a 50% ethanol solution, extracting at 65°C for 1.5 hours.
[0022] In the step (2), the solid content of the concentrated extract is 33%, which is in the medium to high concentration range. It can reduce the added volume and avoid excessive viscosity due to excessive concentration. Its effect can be achieved by waiting for natural volatilization without deep evaporation, effectively reducing the damage of high temperature or long-term heating to the heat-sensitive antibacterial components of chlorogenic acid, volatile oil, and flavonoids in the herbal plants, thereby retaining their biological activity to the maximum extent.
[0023] In the step (4), the amount of plant ash powder added is 3% of the absolute dry mass of the fiber raw material for papermaking, and the amount of concentrated extract added, calculated as the effective bactericidal component therein, is 0.7% of the absolute dry mass of the fiber raw material for papermaking.
[0024] In the step (4), the pulp concentration during mixing is 3%. A pulp concentration of 3% belongs to a medium to low free pulp state, with moderate spacing between fibers and good fluidity. At this concentration, the added wood ash powder and concentrated herbal extract are more easily diffused and suspended in the pulp, avoiding the "embedding" or "bridging" phenomenon caused by excessively high concentration, and helping to achieve effective retention of fillers and fine substances through a reasonable retention and filtration system, such as cationic starch, PAM, etc., during the subsequent dehydration process of the wire.
[0025] In the step (5), the drying temperature is 95°C.
[0026] A type of paper produced by the papermaking process.
[0027] The paper has antibacterial properties, and the antibacterial rate against Escherichia coli and Staphylococcus aureus is 77%.
[0028] The key design point of the present invention is that the herbaceous plants are used to give the paper a natural antibacterial function. The resulting paper has long-lasting antibacterial properties, with an inhibition rate of over 75% against common bacteria such as Escherichia coli, Staphylococcus aureus, and mold. It is suitable for use in sanitary paper, packaging paper, book paper, etc., extending the service life of the paper and preventing mold. Wood ash is a resource utilization of agricultural waste, reducing incineration pollution; herbaceous plants are renewable resources, replacing chemical antibacterial agents such as triclosan and quaternary ammonium salts, reducing environmental pollution and human health risks; and the minerals in wood ash can increase the ash content and alkaline reserve of paper, enhance durability, and are suitable for archival paper, calligraphy and painting paper, and other papers that need to be preserved for a long time. The raw materials of the present invention are widely available and low in cost, suitable for resource recycling projects, and promote a green circular economy. Moreover, the method can be modified on the basis of existing papermaking processes without the need for major equipment investment, and can be promoted in light industrialization.
[0029] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all of these should be considered as the scope of protection of the present invention.
Claims
1. A papermaking method with the addition of wood ash and sterilized herbs, characterized in that: include: (1) Ash pretreatment: Grind the dried ash and sieve it to obtain ash powder with uniform particle size; (2) Preparation of bactericidal herb extract: Select herbal plants with bactericidal effects, wash and chop them, and then use water extraction or alcohol extraction to obtain an extract, and then concentrate the extract to obtain a concentrated extract; (3) Pulping: The fiber raw material for papermaking is subjected to conventional pulping treatment to obtain pulp; (4) Adding and mixing: The wood ash powder obtained in step (1) and the concentrated extract obtained in step (2) are added to the pulp obtained in step (3), and the mixture is stirred and mixed to form a mixed pulp containing wood ash and bactericidal components; (5) Papermaking: The mixed pulp obtained in step (4) is subjected to papermaking, pressing, and drying to obtain paper containing wood ash and bactericidal herbal components.
2. The method for making paper by adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (1), the particle size of the wood ash is 80 mesh to 200 mesh.
3. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (2), the herbal plants with bactericidal efficacy are selected from one or more of mugwort, honeysuckle, coptis chinensis, isatis root, perilla, and mint.
4. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (2), the water extraction method is: mixing the chopped herb with water in a mass ratio of 1:5 to 1:15, and extracting at 60°C to 90°C for 1 to 3 hours; the alcohol extraction method is: using an ethanol solution with a concentration of 30% to 70%, and extracting at 50°C to 80°C for 1 to 2 hours.
5. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (2), the solid content of the concentrated extract is 20% to 40%.
6. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (4), the amount of the wood ash powder added is 1% to 10% of the absolute dry mass of the fiber raw material for papermaking, and the amount of the concentrated extract added is 0.1% to 2% of the absolute dry mass of the fiber raw material for papermaking, calculated based on the effective bactericidal components therein.
7. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (4), the concentration of the pulp during mixing is 2% to 5%.
8. The papermaking method of adding wood ash and sterilized herbs according to claim 1, characterized in that: In the step (5), the drying temperature is 80°C to 120°C.
9. Paper produced by the papermaking method according to any one of claims 1 to 8.
10. The paper according to claim 9, characterized in that The paper has antibacterial properties, and the antibacterial rates against Escherichia coli and Staphylococcus aureus are not less than 70%.