Composite paper cone and preparation method and application thereof

Abstract

The present invention provides a composite paper cone and a preparation method and application thereof. The composite paper cone comprises a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank. The raw material for preparing the paper cone blank is non-wood pulp, and the material of the surface treatment layer comprises nanocellulose and chitosan. 100% non-wood pulp is used as the raw material for preparing the paper cone blank, and nanocellulose and chitosan are coated on the surface of the paper cone blank by surface treatment, so that the obtained composite paper cone has a higher modulus, and the preparation process is simple and can be mass-produced, while avoiding the use of wood pulp, reducing production costs and reducing carbon emissions.

Description

Technical Field

[0001] The invention belongs to the technical field of loudspeakers, and in particular relates to a composite paper cone and a preparation method and application thereof. Background Art

[0002] The main sound-generating component of a speaker is the diaphragm, and the performance of the diaphragm depends on the geometry of the diaphragm, the material of the diaphragm, and the processing technology of the diaphragm. Paper cone is the most commonly used and common diaphragm material. It has suitable internal damping characteristics, low density, and high strength, which is the goal pursued by high-quality paper cones.

[0003] At present, the pulp used to make paper basins generally uses mixed pulps such as wood pulp, cotton pulp, and wool pulp as the basic pulp, and adds some reinforcing fibers such as carbon fiber, mineral fiber, and bulletproof fiber to the basic pulp, and uses it with other functional additives to achieve performance requirements. In the context of pursuing environmental protection, making full use of non-wood forest resources plays an important role in ensuring wood safety, low-carbon green development, and improving people's livelihood. As a grass plant, bamboo has a fiber morphology and cellulose content quality between coniferous wood and broad-leaved wood. The bamboo pulp produced is comparable to wood pulp. The bamboo pulp fiber length is longer than that of broad-leaved wood, the cell wall microstructure is special, the beating strength and ductility are good, and the bleached pulp has good optical properties. At the same time, bamboo has a high cellulose content and is an excellent fiber raw material for papermaking. The cell composition of bamboo pulp is relatively complex. In addition to fibrous cells of varying lengths, there are also a large number of non-fibrous cells. These non-fibrous cells have various shapes, such as rods and spheres. When bamboo pulp is used alone as a raw material to make paper basins, the strength is low and cannot meet the use requirements. Therefore, in paper basin materials, bamboo pulp is generally added as an auxiliary pulp to meet performance requirements.

[0004] CN101280530A discloses a method for preparing drum paper, which includes two steps: beating and hot pressing. The beating is to beat 10-20 kg of 3-6 mm bamboo fiber with 500-1500 kg of water in a beating machine for 8-12 hours, and the hot pressing is to keep the beaten bamboo pulp at 150-200° C. and 100-600 kg of pressure for 20-40 seconds. However, the method for preparing drum paper requires beating the bamboo fiber for 8-12 hours, which is time-consuming and energy-consuming.

[0005] CN101213870A discloses a speaker vibration plate, which uses bamboo fiber whose beating degree is reduced to a microfibrillated state for papermaking, and mixes more than 40% of the bamboo fiber whose beating degree is greater than the microfibrillated state to improve performance, and the vibration plate also adds additives such as polylactic acid, raw rubber, and polyvinyl alcohol. However, the bamboo pulp fiber used in the invention has a high beating degree, and the process of mixing bamboo fibers with different beating degrees is complicated. At the same time, some petroleum-based additives are used, which is not environmentally friendly.

[0006] From the above, it can be seen that the paper cones prepared using non-wood pulp as pulp provided in the prior art are difficult to meet the requirements of high modulus, and generally the paper cones are improved by increasing the beating degree or adding some reinforcing additives (mostly petroleum-based additives). The increase in the beating degree will lead to high energy consumption and increased carbon emissions. At the same time, the addition of some petroleum-based additives will also consume fossil energy.

[0007] Therefore, developing a composite paper cone with high modulus and using non-wood pulp as a raw material is a technical problem that urgently needs to be solved in the field. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a composite paper cone and a preparation method and application thereof. The composite paper cone is formed by coating a surface treatment layer on the surface of a paper cone blank, and limiting the preparation raw material of the paper cone blank to non-wood pulp, and the material of the surface treatment layer includes nanocellulose and chitosan, so that the obtained composite paper cone has a higher modulus and strength, which can effectively improve the performance of the speaker when used in the speaker.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a composite paper cone, the composite paper cone comprising a paper cone blank, the surface of the paper cone blank being coated with a surface treatment layer;

[0011] The raw material for preparing the paper basin blank is non-wood pulp;

[0012] The materials of the surface treatment layer include nanocellulose and chitosan.

[0013] The composite paper basin provided by the present invention includes a paper basin blank, the surface of which is coated with a surface treatment layer, the raw material for preparing the paper basin blank is non-wood pulp, and the material of the surface treatment layer includes nanocellulose and chitosan. First of all, the present invention limits the raw material for preparing the paper basin blank to non-wood pulp, and uses 100% non-wood pulp as the base pulp to make the paper basin blank, and uses the surface treatment layer formed by biomass-based additives (nanocellulose and chitosan), thereby avoiding the use of wood pulp and petroleum-based additives, which not only reduces costs, but also effectively reduces carbon emissions; secondly, the present invention uses a surface treatment method to coat nanocellulose and chitosan on the surface of the paper basin blank. Compared with the method of adding into the pulp, it can reduce the use of nanocellulose and effectively improve the reinforcement effect. Specifically, when nanocellulose is used to reinforce bamboo pulp fiber, since its surface is negatively charged, it is generally used in combination with other cationic additives (such as cationic polyacrylamide, cationic starch, etc.), and most of them are cationic additives. Adding it into the pulp will cause most of the added ingredients to be lost during the papermaking process, with a low retention rate, a large amount used, and limited performance improvement effects. Therefore, the present invention adopts a surface coating method and cooperates with chitosan for synergistic effect. Chitosan, as a deacetylated product of chitin, has good film-forming properties and a structure similar to cellulose. It has good compatibility with fibers and can quickly form a film on the surface of paper to fill the gaps between bamboo pulp fibers. At the same time, the non-wood pulp fibers, nanocellulose, and chitosan surfaces are rich in hydroxyl groups to form hydrogen bonds to interact with each other, further enhancing the bonding force between the fibers and improving the strength of the paper cone. When it is applied to a speaker, it can suppress the split vibration of the speaker in the high frequency band, thereby expanding the frequency response range of the speaker and improving the sensitivity of the speaker.

[0014] Preferably, the non-wood pulp includes any one of bamboo pulp, straw pulp or bagasse pulp, or a combination of at least two of them, preferably bamboo pulp.

[0015] Preferably, the paper basin blank is obtained by sequentially beating, diluting, filtering, forming and hot pressing the non-wood pulp.

[0016] Preferably, the beating degree of the non-wood pulp is 18-23°SR, such as 19°SR, 20°SR, 21°SR or 22°SR.

[0017] Preferably, the diameter of the nanocellulose is 5 to 50 nm, for example, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 40 nm or 50 nm.

[0018] Preferably, the length of the nanocellulose is 10 to 1000 nm, for example, 20 nm, 40 nm, 60 nm, 80 nm, 100 nm, 200 nm, 400 nm, 600 nm or 800 nm.

[0019] It should be noted that the nanocellulose mentioned in the present invention refers to a cellulose-based substance with at least one dimension at the nanometer level, which has a low thermal expansion coefficient, a high specific surface area, good mechanical properties and optical properties, and contains a large number of hydroxyl groups on the surface. When used in paper basins, it can produce synergy with chitosan and show a good reinforcement effect.

[0020] Preferably, the viscosity of the chitosan is 100-300 Pa·s, for example, 120 Pa·s, 140 Pa·s, 160 Pa·s, 180 Pa·s, 200 Pa·s, 220 Pa·s, 240 Pa·s, 260 Pa·s or 280 Pa·s.

[0021] In a second aspect, the present invention provides a method for preparing the composite paper cone as described in the first aspect, the preparation method comprising: immersing the paper cone blank in a mixed aqueous solution containing nanocellulose and chitosan, taking out and drying to obtain the composite paper cone.

[0022] Preferably, the mixed aqueous solution containing nanocellulose and chitosan is obtained by mixing an aqueous solution containing nanocellulose and an aqueous solution containing chitosan.

[0023] Preferably, the mass ratio of the aqueous solution containing nanocellulose to the aqueous solution containing chitosan is 1:(0.5-5), for example, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4 or 1:4.5, and more preferably 1:(1-4).

[0024] Preferably, the mass percentage of nanocellulose in the nanocellulose-containing aqueous solution is 0.25-2%, for example, 0.5%, 0.7%, 0.9%, 1.1%, 1.3%, 1.5%, 1.7% or 1.9%.

[0025] Preferably, the mass percentage of chitosan in the chitosan-containing aqueous solution is 0.5-2%, for example, 0.7%, 0.9%, 1.1%, 1.3%, 1.5%, 1.7% or 1.9%.

[0026] Preferably, the immersion time is 40 to 80 seconds, for example, 45 seconds, 50 seconds, 55 seconds, 60 seconds, 65 seconds, 70 seconds or 75 seconds.

[0027] Preferably, the drying temperature is 100-120°C, for example, 107°C, 109°C, 111°C, 113°C, 115°C, 117°C or 119°C.

[0028] Preferably, the drying time is 30 to 60 min, for example, 35 min, 40 min, 45 min, 50 min or 55 min.

[0029] As a preferred technical solution of the present invention, the method for preparing the composite paper cone comprises the following steps:

[0030] (1) mixing an aqueous solution of nanocellulose having a mass percentage of 0.25 to 2% and an aqueous solution of chitosan having a mass percentage of 0.5 to 2% in a mass ratio of 1:(0.5 to 5) to obtain a mixed aqueous solution;

[0031] (2) Immersing the paper cone blank in the mixed aqueous solution obtained in step (1) for 40 to 80 seconds, taking it out and drying it at 105 to 200° C. for 30 to 60 minutes to obtain the composite paper cone.

[0032] In a third aspect, the present invention provides a loudspeaker, comprising the composite paper cone as described in the first aspect.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The composite paper basin provided by the present invention comprises a paper basin blank and a surface treatment layer coated on the surface of the paper basin blank, wherein the preparation raw material of the paper basin blank is non-wood pulp, and the material of the surface treatment layer comprises nanocellulose and chitosan; by using 100% non-wood pulp as the base pulp and adding biomass-based additives to match the process conditions, the use of wood pulp and petroleum-based additives is avoided, which not only reduces costs but also effectively reduces carbon emissions;

[0035] (2) The composite paper cone provided by the present invention is coated with nanocellulose and chitosan on the surface of the paper cone blank by surface treatment. The nanocellulose and chitosan can produce a synergistic effect to improve the compatibility, thereby greatly improving the modulus of the paper cone. When used in a speaker, it can effectively improve the performance of the speaker. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0037] The information of some raw materials involved in the specific implementation of the present invention is as follows:

[0038] Cationic styrene acrylic emulsion: purchased from Guangzhou Yunqi Electroacoustic Technology Development Co., Ltd.

[0039] Example 1

[0040] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0041] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0042] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0043] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0044] (2) mixing a 1% by mass nanocellulose aqueous solution and a 1% by mass chitosan aqueous solution in a mass ratio of 1:1 to obtain a mixed aqueous solution;

[0045] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0046] Example 2

[0047] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0048] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0049] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0050] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 20°SR, then adding water to dilute, stirring and dispersing at a speed of 800 rpm for 6 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0051] (2) mixing a nanocellulose aqueous solution having a mass percentage of 0.5% and a chitosan aqueous solution having a mass percentage of 1% in a mass ratio of 1:1 to obtain a mixed aqueous solution;

[0052] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 40 seconds, and finally dried at 110° C. for 35 minutes to obtain the composite paper cone.

[0053] Example 3

[0054] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0055] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0056] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0057] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 23°SR, then adding water to dilute, stirring and dispersing at a speed of 1200 rpm for 3 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0058] (2) mixing a 2% by mass nanocellulose aqueous solution and a 1% by mass chitosan aqueous solution in a mass ratio of 1:1 to obtain a mixed aqueous solution;

[0059] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 40 seconds, and finally dried at 110° C. for 35 minutes to obtain the composite paper cone.

[0060] Example 4

[0061] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0062] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0063] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0064] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 20°SR, then adding water to dilute, stirring and dispersing at a speed of 1200 rpm for 3 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0065] (2) mixing a 2% by mass nanocellulose aqueous solution and a 2% by mass chitosan aqueous solution at a mass ratio of 1:5 to obtain a mixed aqueous solution;

[0066] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 80 seconds, and finally dried at 105° C. for 60 minutes to obtain the composite paper cone.

[0067] Example 5

[0068] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0069] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0070] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0071] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 20°SR, then adding water to dilute, stirring and dispersing at a speed of 800 rpm for 6 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0072] (2) mixing a nanocellulose aqueous solution having a mass percentage of 0.5% and a chitosan aqueous solution having a mass percentage of 0.5% in a mass ratio of 1:0.5 to obtain a mixed aqueous solution;

[0073] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 80 seconds, and finally dried at 105° C. for 60 minutes to obtain the composite paper cone.

[0074] Example 6

[0075] A composite paper cone, comprising a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank;

[0076] The raw material for preparing the paper basin blank is bamboo pulp, and the materials of the surface treatment layer include nanocellulose and chitosan;

[0077] The method for preparing the composite paper cone provided in this embodiment comprises the following steps:

[0078] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 20°SR, then adding water to dilute, stirring and dispersing at a speed of 800 rpm for 6 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0079] (2) mixing a 1% by mass nanocellulose aqueous solution and a 1% by mass chitosan aqueous solution in a mass ratio of 1:4 to obtain a mixed aqueous solution;

[0080] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 80 seconds, and finally dried at 105° C. for 60 minutes to obtain the composite paper cone.

[0081] Example 7

[0082] A composite paper basin, which differs from Example 1 only in that the absolute dry bamboo pulp in step (1) is replaced by bamboo pulp and straw pulp in an absolute dry mass ratio of 1:1, and other materials and preparation methods are the same as those in Example 1.

[0083] Example 8

[0084] A composite paper basin, which differs from Example 1 only in that the absolute dry bamboo pulp in step (1) is replaced by bamboo pulp and bagasse pulp in an absolute dry mass ratio of 1:1, and other materials and preparation methods are the same as those in Example 1.

[0085] Comparative Example 1

[0086] A paper basin, the preparation method of which comprises: weighing 10g of absolutely dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a rotation speed of 1000rpm for 4min, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1min to obtain the paper basin.

[0087] Comparative Example 2

[0088] A composite paper basin, the preparation method of which comprises: weighing 10g of absolute dry bamboo pulp, adding water to beat the pulp to a beating degree of 18°SR, then adding water to dilute, stirring and dispersing at a rotation speed of 1000rpm for 2min, then adding 0.1g of nanocellulose to continue dispersing for 2min, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1min to obtain the composite paper basin.

[0089] Comparative Example 3

[0090] A composite paper cone, the preparation method of which comprises the following steps:

[0091] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0092] (2) The paper cone blank obtained in step (1) is immersed in a nanocellulose aqueous solution with a mass percentage of 0.5% for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0093] Comparative Example 4

[0094] A composite paper cone, the preparation method of which comprises the following steps:

[0095] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0096] (2) The paper cone blank obtained in step (1) is immersed in water for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0097] Comparative Example 5

[0098] A composite paper cone, the preparation method of which comprises the following steps:

[0099] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0100] (2) The paper cone blank obtained in step (1) is immersed in a chitosan aqueous solution with a mass percentage of 0.5% for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0101] Comparative Example 6

[0102] A composite paper cone, the preparation method of which comprises the following steps:

[0103] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0104] (2) The paper cone blank obtained in step (1) is immersed in a cationic styrene-acrylic emulsion with a mass percentage of 0.5% for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0105] Comparative Example 7

[0106] A composite paper cone, the preparation method of which comprises the following steps:

[0107] (1) Weighing 10 g of absolute dry bamboo pulp, adding water to beat the pulp until the beating degree is 18°SR, then adding water to dilute, stirring and dispersing at a speed of 1000 rpm for 4 minutes, adjusting the pulp concentration to 0.1%, then filtering and forming, and finally hot pressing and drying at 180°C for 1 minute to obtain a paper basin blank;

[0108] (2) mixing a nanocellulose aqueous solution having a mass percentage of 1% and a cationic styrene acrylic emulsion having a mass percentage of 1% in a mass ratio of 1:1 to obtain a mixed aqueous solution;

[0109] (3) The paper cone blank obtained in step (1) is immersed in the mixed aqueous solution obtained in step (2) for 50 seconds, and finally dried at 100° C. for 40 minutes to obtain the composite paper cone.

[0110] Comparative Example 8

[0111] A composite paper cone, the preparation method of which comprises the following steps:

[0112] (1) Weigh 10 g of absolute dry bamboo pulp, add water to beat the pulp until the beating degree is 18°SR, then add water to dilute, stir and disperse at a speed of 1000 rpm for 4 minutes, adjust the pulp concentration to 0.1%, and filter the water on the wire to obtain a wet paper cone;

[0113] (2) Spraying a nanocellulose aqueous solution with a mass fraction of 0.5% on the front side of the paper cone obtained in step (1), and hot-pressing and drying at 180° C. for 1 min to obtain the paper cone.

[0114] Comparative Example 9

[0115] A composite paper cone, the preparation method of which comprises the following steps:

[0116] (1) Weigh 10 g of absolute dry bamboo pulp, add water to beat the pulp until the beating degree is 18°SR, then add water to dilute, stir and disperse at a speed of 1000 rpm for 4 minutes, adjust the pulp concentration to 0.1%, and filter the water on the wire to obtain a wet paper cone;

[0117] (2) spraying an aqueous solution of nanocellulose with a mass fraction of 0.5% on the front side of the wet paper cone obtained in step (1), and hot-pressing and drying at 180° C. for 1 min to obtain a paper cone;

[0118] (3) The paper cone obtained in step (4) is immersed in a chitosan aqueous solution with a mass percentage of 0.5% for 50 seconds, and then dried at 110° C. for 40 minutes to obtain the composite paper cone.

[0119] Comparative Example 10

[0120] A paper cone, the preparation method of which comprises the following steps:

[0121] (1) Weigh 10 g of absolute dry bamboo pulp, add water to beat the pulp until the beating degree is 18°SR, add water to dilute, stir and disperse at a speed of 1000 rpm for 4 minutes, adjust the pulp concentration to 0.1%, and filter the water on the wire to obtain a wet paper cone;

[0122] (2) spraying an aqueous solution of nanocellulose with a mass fraction of 0.5% on the front and back of the wet paper cone obtained in step (1), and hot-pressing and drying at 180° C. for 1 min to obtain the paper cone.

[0123] Comparative Example 11

[0124] A composite paper cone, the preparation method of which comprises the following steps:

[0125] (1) Weigh 10 g of absolute dry bamboo pulp, add water to beat the pulp until the beating degree is 18°SR, then add water to dilute, stir and disperse at a speed of 1000 rpm for 4 minutes, adjust the pulp concentration to 0.1%, and filter the water on the wire to obtain a wet paper cone;

[0126] (2) spraying an aqueous solution of nanocellulose with a mass fraction of 0.5% on the front and back of the wet paper cone obtained in step (1), and hot-pressing and drying at 180° C. for 1 min to obtain the paper cone;

[0127] (3) The paper cone obtained in step (2) is immersed in a chitosan aqueous solution with a mass percentage of 0.5% for 50 seconds, and then dried at 110° C. for 40 minutes to obtain the composite paper cone.

[0128] Performance Test:

[0129] (1) Density: The mass of the sample is measured by an analytical balance, and the thickness of the sample is measured by a thickness meter. The thickness and mass of the same sample are measured three times and the average value is taken to calculate the density of the sample;

[0130] (2) Modulus: Young's modulus was measured using the material parameter test module MPM in the KLIPPEL test system;

[0131] The paper cones provided in Examples 1 to 8 and Comparative Examples 1 to 11 were tested according to the above test method. The test results are shown in Table 1:

[0132] Table 1

[0133]

[0134]

[0135] From Table 1 we can see that:

[0136] The density of the composite paper cone obtained in Examples 1 to 6 is 0.54 to 0.61 g / cm 3 , the modulus is as high as 3.83~4.28Gpa, with lower density and higher modulus;

[0137] Compared with Example 1, the paper basin provided in Comparative Example 1 has not been surface treated, and its modulus is only 3.1 Gpa; the composite paper basin prepared by the method of adding nanocellulose in the pulp in Comparative Example 2 also has a low modulus of only 3.8 Gpa; and the paper basins provided in Comparative Examples 3 and 4 are respectively impregnated with 0.5% nanocellulose aqueous solution and water for the paper basin blanks, and the moduli of the obtained paper basins are only 2.01 Gpa and 1.99 Gpa, indicating that the enhancement effect cannot be achieved when only a 0.5% nanocellulose aqueous solution is used for surface treatment; the effects of impregnation with only chitosan in Comparative Example 5, impregnation with cationic styrene-acrylic emulsion in Comparative Example 6, and impregnation with a combination of nanocellulose and cationic styrene-acrylic emulsion in Comparative Example 7 are not ideal, and the modulus of the paper basin is not significantly improved.

[0138] Compared with Example 1, in Comparative Examples 8 and 10, nanocellulose is sprayed on the surface of a wet paper cone. Since nanocellulose is deposited on the surface of the wet paper, water evaporates rapidly during the subsequent hot pressing and drying process, and hydrogen bonds are formed between the nanocellulose and the bamboo pulp fibers, thereby enhancing the binding force between the fibers and greatly improving the strength performance of the paper cone. However, in Comparative Examples 9 and 11, the surface of the paper cone sprayed with nanocellulose is further treated with chitosan, and the modulus of the resulting composite paper cone decreases instead. This may be due to the decrease in the surface hydrophilicity of the paper sprayed with nanocellulose. When chitosan is impregnated, chitosan cannot effectively form a film on the surface of the bamboo pulp fibers. At the same time, the impregnation causes the hydrogen bonds inside the bamboo pulp fibers to fail, and the performance decreases after drying again. However, it should be emphasized that the preparation of the composite paper cone obtained by this spraying method is very difficult, which is not conducive to large-scale industrial production.

[0139] Compared with Example 1, the modulus of the composite paper basin obtained by Example 7 using absolute dry bamboo pulp and straw pulp and Example 8 using absolute dry bamboo pulp and bagasse pulp decreased slightly, but increased significantly compared with the modulus of the bamboo pulp paper basin in Comparative Example 1.

[0140] The applicant declares that the present invention illustrates a composite paper cone and its preparation method and application through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A composite paper cone, characterized in that: The composite paper cone comprises a paper cone blank and a surface treatment layer coated on the surface of the paper cone blank; The raw material for preparing the paper basin blank is non-wood pulp; The material of the surface treatment layer includes nanocellulose and chitosan; The composite paper cone is prepared by the following method, which comprises the following steps: The paper cone blank is immersed in a mixed aqueous solution containing nanocellulose and chitosan, taken out and dried to obtain the composite paper cone.

2. The composite paper cone according to claim 1, characterized in that: The non-wood pulp includes any one of bamboo pulp, straw pulp or bagasse pulp, or a combination of at least two of them.

3. The composite paper cone according to claim 1, characterized in that: The non-wood pulp is bamboo pulp.

4. The composite paper cone according to claim 1, characterized in that: The paper basin blank is obtained by sequentially beating, diluting, filtering, forming and hot pressing the non-wood pulp.

5. The composite paper cone according to claim 1, characterized in that: The beating degree of the non-wood pulp is 18-23°SR.

6. The composite paper cone according to claim 1, characterized in that: The diameter of the nanocellulose is 5 to 50 nm.

7. The composite paper cone according to claim 1, characterized in that: The length of the nanocellulose is 10 to 1000 nm.

8. The composite paper cone according to claim 1, characterized in that: The viscosity of the chitosan is 100-300 Pa·s.

9. A method for preparing the composite paper cone according to any one of claims 1 to 8, characterized in that: The preparation method comprises: immersing a paper cone blank in a mixed aqueous solution containing nanocellulose and chitosan, taking out and drying, and obtaining the composite paper cone.

10. The preparation method according to claim 9, characterized in that: The mixed aqueous solution containing nanocellulose and chitosan is obtained by mixing an aqueous solution containing nanocellulose and an aqueous solution containing chitosan.

11. The preparation method according to claim 10, characterized in that: The mass ratio of the aqueous solution containing nanocellulose to the aqueous solution containing chitosan is 1:(0.5-5).

12. The preparation method according to claim 11, characterized in that: The mass ratio of the aqueous solution containing nanocellulose to the aqueous solution containing chitosan is 1:(1-4).

13. The preparation method according to claim 10, characterized in that: The mass percentage of nanocellulose in the aqueous solution containing nanocellulose is 0.25-2%.

14. The preparation method according to claim 10, characterized in that: The mass percentage of chitosan in the chitosan-containing aqueous solution is 0.5-2%.

15. The preparation method according to claim 9, characterized in that: The immersion time is 40 to 80 seconds.

16. The preparation method according to claim 9, characterized in that: The drying temperature is 100-120°C.

17. The preparation method according to claim 9, characterized in that: The drying time is 30 to 60 minutes.

18. A loudspeaker, characterized in that: The speaker comprises the composite paper cone as claimed in any one of claims 1 to 8.

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