阅读说明：本技术 一种咖啡滤纸及其制备方法 (Coffee filter paper and preparation method thereof ) 是由 周家俊 刘敏 邹小峰 胡莉萍 于 2019-11-19 设计创作，主要内容包括：本发明涉及造纸技术领域,尤其涉及一种咖啡滤纸及其制备方法。其包括用于贴合于滤杯的外层和用于接触咖啡粉和水的内层；按照质量份,所述内层包括100份纸浆、5-10份聚丙烯酸酯、8-18份聚硅氧烷、5-12份气相二氧化硅以及3-5份羟甲基纤维素；所述外层包括60-80份纸浆、20-40份化纤、5-12份气相二氧化硅以及10-20份木质素。本发明通过设置内层和外层,并对内层和外层采用不同的原料制备,使得内层具有疏水性、从而提高滤纸的滤出速度并减少破损可能性,而外层具有亲水性、使得滤纸能够更好地贴合于滤杯。(The invention relates to the technical field of papermaking, in particular to coffee filter paper and a preparation method thereof. It comprises an outer layer for fitting to the filter bowl and an inner layer for contacting the coffee powder and water; according to the mass parts, the inner layer comprises 100 parts of paper pulp, 5-10 parts of polyacrylate, 8-18 parts of polysiloxane, 5-12 parts of fumed silica and 3-5 parts of hydroxymethyl cellulose; the outer layer comprises 60-80 parts of paper pulp, 20-40 parts of chemical fiber, 5-12 parts of fumed silica and 10-20 parts of lignin. According to the invention, the inner layer and the outer layer are arranged and prepared from different raw materials, so that the inner layer has hydrophobicity, the filtering speed of the filter paper is increased, the damage possibility is reduced, and the outer layer has hydrophilicity, so that the filter paper can be better attached to the filter cup.)

1. A coffee filter paper characterized by: comprises an outer layer for fitting to the filter bowl and an inner layer for contacting the coffee powder and water; according to the mass parts, the inner layer comprises 100 parts of paper pulp, 5-10 parts of polyacrylate, 8-18 parts of polysiloxane, 5-12 parts of fumed silica and 3-5 parts of hydroxymethyl cellulose; the outer layer comprises 60-80 parts of paper pulp, 20-40 parts of chemical fiber, 5-12 parts of fumed silica and 10-20 parts of lignin.

2. A coffee filter paper as claimed in claim 1, wherein: the inner layer also comprises 5-8 parts of starch and 1-1.5FPU/g of amylase.

3. A coffee filter paper as claimed in claim 1, wherein: the composite board further comprises an intermediate layer, wherein the intermediate layer comprises 2-8 parts of lignin-carbohydrate complex and 100 parts of adhesive.

4. A coffee filter paper as claimed in claim 3, wherein: the adhesive is one or more of polyurethane resin and polyolefin resin.

5. A coffee filter paper as claimed in claim 1, wherein: the chemical fiber is one or more of polypropylene fiber and polyethylene fiber.

6. A method of making coffee filter paper according to any one of claims 1 to 5, wherein: the method comprises the following steps:

preparing an inner layer: a. mixing polysiloxane and fumed silica, stirring at 60-75 deg.C and pH of 6-7 for 30-60min, cooling to 20-25 deg.C, adding polyacrylate, and ultrasonic dispersing for 45-65min to obtain mixed solution; b. performing steam explosion treatment on the paper pulp, spraying the mixed solution heated to 80-100 ℃ on the surface of the paper pulp, and standing for 20-50 min; c. adding the obtained paper pulp and hydroxymethyl cellulose into water, and defibering for 15-20min to obtain pulp; d. making the pulp into paper to obtain an inner layer;

preparing an outer layer: performing steam explosion treatment on the paper pulp, adding the paper pulp, chemical fiber, fumed silica and lignin into water, defibering for 15-20min to obtain pulp, and making paper with the pulp to obtain an outer layer;

and compounding and shaping the inner layer and the outer layer by using a pressing roller to obtain the coffee filter paper.

7. The method for preparing coffee filter paper according to claim 6, wherein: in the step c, the paper pulp obtained in the step b, the hydroxymethyl cellulose, the starch and the amylase are added into water together, and are defibered for 15-20min under the conditions of 85-90 ℃ and pH6-7, so that the pulp is obtained.

8. The method for preparing coffee filter paper according to claim 6, wherein: further comprising the steps of: preparing an intermediate layer: adding lignin-carbohydrate into the adhesive, and dispersing for 10-15min at an ultra speed; and coating the middle layer between the inner layer and the outer layer, and then performing compression roller and heating composite forming.

9. The method for preparing coffee filter paper according to claim 6, wherein: in the step (3), the temperature of the composite shaping is 130-150 ℃, and the pressure is 0.28-0.35 MPa.

10. The method for preparing coffee filter paper according to claim 6, wherein: and (3) after rolling, compounding and shaping, cooling the composite paper to 20-25 ℃ within 10-20s to obtain the coffee filter paper.

Technical Field

The invention relates to the technical field of papermaking, in particular to coffee filter paper and a preparation method thereof.

Background

The coffee filter paper is a filter material made of paper fiber material with a plurality of pores, the shape of the filter paper is mostly circular which is convenient to fold, and the filter paper with a corresponding pocketed structure used by a special coffee machine is also provided. In addition to simple coffee machines with self-contained screens, such as french press, most coffee machines use coffee filter paper, most typically filter paper brewing to make coffee. The filter paper brewing method is somewhat similar to tea bag, and has the greatest advantages of convenient brewing and no need of other equipment. When in use, the universal coffee filter paper is folded twice and folded into a funnel shape. Placing the filter paper in a funnel or a container, pouring the coffee powder with proper grinding fineness into the filter paper, and slowly brewing the coffee powder with boiled water. The coffee filter paper has the advantages that most coffee grounds can be effectively filtered, and the taste of coffee can be improved compared with that of a filter screen. And the coffee filter paper is disposable, and can be replaced again after being used without cleaning, so that most coffee shops use the coffee filter paper to filter coffee grounds.

The excellent coffee filter paper has the characteristics of strong and uniform water filterability, weak filter paper taste and difficulty in breaking, wherein the water filterability influences the coffee soaking time, the filter paper taste directly influences the coffee aroma, and the difficulty in breaking influences the success or failure of coffee brewing.

Disclosure of Invention

The invention aims to solve the problems and provides coffee filter paper and a preparation method thereof.

The technical scheme for solving the problems is to provide the coffee filter paper which comprises an outer layer and an inner layer, wherein the outer layer is attached to a filter cup, and the inner layer is used for contacting coffee powder and water; according to the mass parts, the inner layer comprises 100 parts of paper pulp, 5-10 parts of polyacrylate, 8-18 parts of polysiloxane, 5-12 parts of fumed silica and 3-5 parts of hydroxymethyl cellulose; the outer layer comprises 60-80 parts of paper pulp, 20-40 parts of chemical fiber, 5-12 parts of fumed silica and 10-20 parts of lignin.

The paper pulp is a fibrous substance prepared by using plant fibers as raw materials through different processing methods. The pulp can be divided into mechanical pulp, chemical pulp and chemimechanical pulp according to the processing method, and can also be divided into wood pulp, straw pulp, hemp pulp, reed pulp, cane pulp, bamboo pulp, rag pulp and the like according to the used fiber raw materials. The main components of the pulp, which constitute fibers, are cellulose, and in addition, substances such as hemicellulose, lignin, resin, pigments, pectin, ash and the like in different degrees. Any plant fiber pulp can be adopted in the application, and is preferably one or a mixture of more of poplar pulp, wheat straw pulp, Chinese red pine pulp and eucalyptus pulp.

Fumed silica is produced by hydrolysis of volatile chlorosilanes in an oxyhydrogen flame, and is composed of highly pure amorphous silica, which has hydrophilicity.

And the hydrophilic fumed silica and the active silane are subjected to chemical reaction to obtain the hydrophobic fumed silica. The combination of polyacrylate, polysiloxane, silica can form a superhydrophobic coating.

Hydroxymethyl cellulose is useful as a dispersant and a binder.

Lignin is a complex phenolic polymer formed from three alcohol monomers (p-coumaryl alcohol, coniferyl alcohol, sinapyl alcohol). Lignin is a biopolymer with a three-dimensional network structure formed by connecting three phenylpropane units through ether bonds and carbon-carbon bonds, exists in a woody tissue, and has the main function of hardening cell walls by forming a cross-woven network, and is a main component of secondary walls. The lignin is mainly located between the cellulose fibers and plays a role in resisting pressure. Among woody plants, lignin accounts for 25% and is the second most abundant organic matter in the world (cellulose is the first). The lignin can be extracted from the pulp cooking waste liquid or can be directly purchased from the market.

Preferably, the inner layer also comprises 5-8 parts of starch and 1-1.5FPU/g of amylase, wherein the amylase is α -amylase of BF7658 strain, and the starch is converted into dextrin and oligosaccharide under the action of α -amylase.

Preferably, the wood-plastic composite also comprises an intermediate layer, wherein the intermediate layer comprises 2-8 parts of lignin-carbohydrate complexes and 100 parts of adhesive. The lignin-carbohydrate complex is a lignin-carbohydrate complex which is formed by bonding lignin and polysaccharide (such as polygalactose, xylan, polydextrose and mannose) through a firm covalent bond to form an inhomogeneous macromolecule, contains a lignin rigid segment and a polysaccharide flexible segment, and has good amphipathy, so that the bonding degree of an inner layer and an outer layer can be improved. The method for separating and extracting lignin-carbohydrate complex from plant material includes water solvent extraction, organic solvent extraction, and water-organic solvent combined extraction.

Preferably, the adhesive is one or more of polyurethane resin and polyolefin resin, and is a high-temperature-resistant and non-toxic adhesive.

Preferably, the chemical fiber is one or more of polypropylene fiber and polyethylene fiber.

Another object of the present invention is to provide a method for preparing coffee filter paper, comprising the steps of:

(1) preparing an inner layer: a. mixing polysiloxane and fumed silica, stirring at 60-75 deg.C and pH of 6-7 for 30-60min, cooling to 20-25 deg.C, adding polyacrylate, and ultrasonic dispersing for 45-65min to obtain mixed solution; b. performing steam explosion treatment on the paper pulp, spraying the mixed solution heated to 80-100 ℃ on the surface of the paper pulp, and standing for 20-50 min; c. adding the obtained paper pulp and hydroxymethyl cellulose into water, and defibering for 15-20min to obtain pulp; d. making the pulp into paper to obtain an inner layer;

(2) preparing an outer layer: and (3) performing steam explosion treatment on the paper pulp, adding the paper pulp, chemical fibers, fumed silica and lignin into water, defibering for 15-20min to obtain slurry, and making paper from the slurry to obtain an outer layer.

(3) And compounding and shaping the inner layer and the outer layer by using a pressing roller to obtain the coffee filter paper.

Preferably, wherein the steam explosion parameters are: the paper pulp presoaking water content is 5-10%, the steam pressure is 1.0-2.0MPa, and the processing time is 60-80 s.

Preferably, in step c, the pulp obtained in step b, the hydroxymethyl cellulose, the starch and the amylase are added into water together, and are defibered for 15-20min at the temperature of 85-90 ℃ and the pH of 6-7 to obtain the pulp.

Preferably, the method further comprises the following steps: preparing an intermediate layer: adding lignin-carbohydrate into the adhesive, and dispersing for 10-15min at an ultra speed; and coating the middle layer between the inner layer and the outer layer, and then performing compression roller and heating composite forming.

Preferably, in the step (3), the temperature for composite shaping is 130-150 ℃, and the pressure is 0.28-0.35 MPa.

Preferably, after rolling, compounding and shaping, cooling the composite paper to 20-25 ℃ within 10-20s to obtain the coffee filter paper.

The invention has the beneficial effects that:

1. the inner layer and the outer layer are arranged and prepared from different raw materials, so that the inner layer has hydrophobicity, the filtering speed of the filter paper is improved, and the outer layer has hydrophilicity, and the filter paper can be better attached to the filter cup. In addition, in the inner layer preparation process, the pulp is mixed with the water repellent agent after steam explosion, so that the mixing depth and the uniformity of the pulp and the water repellent agent can be improved, and the water filtration uniformity is further improved. Meanwhile, paper is easily broken when it is wet because some components in the paper are dissolved when it is wet, so that the strength of the paper is reduced, and thus, the hydrophobicity also reduces the possibility of breakage of the filter paper.

2. The outer layer is added with lignin which is insoluble in water under the general condition, and the lignin is combined in the gaps of the wood pulp subjected to steam expansion treatment, so that the strength of the paper can be effectively improved.

3. Starch and a small amount of amylase are added into the inner layer, and the amylase preliminarily degrades the starch into dextrin and oligosaccharide with smaller polymerization degree, so that when the inner layer and the outer layer are combined in a hot-pressing mode, phenolic hydroxyl on lignin of the outer layer and aldehyde groups on the starch oligosaccharide are combined in a condensation mode, and the combination degree of the inner layer and the outer layer is improved.

Detailed Description

The following are specific embodiments of the present invention and further describe the technical solutions of the present invention, but the present invention is not limited to these examples.