KR20110043253A

KR20110043253A - Diaphragm for speaker and method for making thereof

Info

Publication number: KR20110043253A
Application number: KR1020090100290A
Authority: KR
Inventors: 임준우
Original assignee: 광원텍(주)
Priority date: 2009-10-21
Filing date: 2009-10-21
Publication date: 2011-04-27

Abstract

PURPOSE: A diaphragm for a speaker and manufacturing method thereof are provided to obtain excellent environment-friendly effects using red algae pulp. CONSTITUTION: A diaphragm for a speaker is made of materials including fiber extracted from red algae. The materials of the diaphragm are in a pulp state. At least one of wood pulp or synthetic pulp is mixed with fiber extracted from red algae to form the materials of the diaphragm. The weight of the fiber extracted from the red algae is heavier than 10weight% of the total fiber weight of mixed pulp.

Description

Diaphragm for speaker and manufacturing method thereof

The present invention relates to a diaphragm comprising red algae pulp and a method of manufacturing the same, and more particularly, to a diaphragm for a speaker including a red algae pulp having a constant fiber length and a fine fiber diameter.

The diaphragm is the most important part of regenerating the sound source by causing vibration to the speaker, and is generally called cone paper because of its conical shape. The diaphragm receives the vibration of the voice coil and generates sound waves by the compression variation of the air. The sound quality of the speaker, which is an acoustic transducer that converts electrical energy into acoustic energy, is greatly influenced by the diaphragm, and specifically, the sound quality of the speaker depends greatly on the shape and the material of the diaphragm. In the case of diaphragm material, it is known that light material is ideal for high elastic modulus and weight to increase speaker efficiency. In addition, the diaphragm material is preferably a large internal loss (tan δ). In addition, when the physical properties of the diaphragm are changed, it is known that the sound quality and frequency characteristics of the speaker are changed, so that a wide frequency characteristic and good sound quality can be reproduced.

Factors that determine the nature of the sound are largely related to the speaker's ability to reproduce sound over the entire audible frequency band, which is typically expected if the speaker fails to reproduce frequencies up to at least 20 KHz. There are many difficult acoustics. Until now, it has been known that the physically negative audio band is 20 KHz in the maximum audio range.

The speaker aims to improve the efficiency of the speaker and to reproduce the sound source in a wide frequency range with a small energy in one speaker in order to reproduce near the original sound. The role of the diaphragm is very important to achieve this goal of the speaker.

In general, in the diaphragm for a speaker, distortion is generated due to the material of the diaphragm, the vibration of the edge of the diaphragm and the body, and vibrational assembly factors. Therefore, many studies have been conducted to improve the performance of the speaker by minimizing the generation of such sound, and a typical method is to improve the material of the diaphragm.

As described above, the material of the diaphragm for the speaker is known to have a close relationship with the elastic modulus and the internal loss. For this reason, improving the material of the diaphragm can be said to improve the elastic modulus and internal loss of the material, and attempts have been made to reduce the distortion of the diaphragm by improving the elastic modulus and internal loss according to the material of the diaphragm.

In general, speaker diaphragms are manufactured using pulp. In the conventional manufacturing process of the diaphragm using pulp, first, the pulp raw material inflated in the process of beating is beaten by a beater, and then the beaten pulp raw material is condensed in a tank. ) The basic shape is imaged using a shaped mesh plate, and the paper is dewatered. Thereafter, when the dehydrated paper is inserted into a mold and heated, a diaphragm is obtained. On the other hand, by coating a chemical on the surface of the diaphragm made of a pulp material or by further bonding and synthesizing other subsidiary materials, a diaphragm for speaker of higher quality and higher characteristics is manufactured, or a diaphragm is manufactured using a single body such as a carbon sheet. How to do is also known.

Wood, which is a major pulp feed material, is mainly composed of cellulose, hemicellulose, and lignin, and these components constitute the cell wall and the intercellular layer and are present in more than 90% of all species. Subcomponents include resins, essential oils, fats and oils, extracts such as tannins and flavonoids, and other inorganic substances. Among them, cellulose is present in the largest amount of organic compounds present in nature, and is the main component of the plant cell wall. Cellulose is a polymeric material that is insoluble in water, dilute acid and alkali at room temperature. In order to industrially use wood cellulose, it is used as wood sugar by manufacturing paper through hydrolysis, bleaching, refining, etc., or by hydrolyzing wood, and making and using cellulose derivatives through various chemical treatments. Doing. Various operations are performed from the raw material to the pulp, but it can be largely classified into preparation of pulp raw material, pulping, and purification of pulp.

However, as the depletion of wood resources around the world becomes severe, the task of the industry is to produce raw pulp in an environmentally friendly manner while protecting forests and the environment.

One aspect of the present invention is to provide a vibrating plate excellent in intelligibility and original sound reproduction using a more environmentally friendly material and further stable at high volume driving.

Accordingly, another aspect of the present invention is to provide a method for producing pulp using more environmentally friendly materials, and using the same, to provide excellent clarity and reproducibility of sound, and to produce a stable diaphragm even when driving a large volume.

According to one aspect of the present invention, there is provided a diaphragm for a speaker formed of a material containing fibers extracted from red algae.

It is preferable that the material of the diaphragm is a pulp of fibers extracted from red algae.

The material of the diaphragm is preferably a mixed pulp formed by mixing fibers extracted from red algae with wood pulp or synthetic pulp.

The material of the diaphragm is preferably at least 10% by weight of fibers extracted from red algae based on the total fiber weight of the mixed pulp.

The red algae is preferably any one or more selected from the group consisting of Locust spruce, Dolga persimmon, Gambling and Noodles.

According to another aspect of the present invention, there is provided a method of manufacturing a diaphragm for a speaker comprising the step of forming a pulp using a material comprising fibers extracted from red algae, and forming the pulp in the shape of a diaphragm in a mold. do.

In the forming of the pulp, it is preferable to form a mixed pulp by mixing fibers extracted from red algae with synthetic pulp or pulverized wood pulp.

The fiber extracted from the red algae is preferably mixed at least 10% by weight based on the total fiber weight of the mixed pulp.

The red algae pulp has a constant fiber length and finer fiber diameter than the general wood pulp, and thus the diaphragm including the red algae pulp of the present invention has excellent clarity and excellent reproducibility as compared to the wood pulp diaphragm, and is stable even when driving a large volume. Indicates. In addition, in order to obtain wood pulp, forests must be harvested and it takes a long time to recover forests. However, in the case of using red algae pulp as in the present invention, it is effective in terms of environmental protection to protect the natural environment.

In the present invention, there is provided a diaphragm for a speaker formed of a material containing the fiber extracted from red algae, preferably, the material of the diaphragm is used to form a fiber extracted from the red alga in a pulp state.

Extracted fiber and red algae pulp from red algae for use in the present invention comprises the steps of: (a) immersing red algae in an acidic solution for a period of time, followed by washing with water and dehydrating; (b) extracting the gel by immersing the dehydrated red alga in an extraction solvent for a predetermined time; (c) bleaching the extracted gel and residue in multiple stages; And (d) collecting and fiberizing the bleached red algae, and then preparing a red algae pulp.

More specifically, red algae are immersed in an acidic solution of pH 2-3 for a period of time, washed with water and then dehydrated. At this time, through the process of immersing the red algae in an acidic aqueous solution for a certain time, impurities are removed and the skin of the red algae is softened.

When the washed and dehydrated red alga is immersed in the extraction solvent, the gel contained in the red alga is extracted with the extraction solvent. At this time, the extraction solution may be used ordinary water, ethyl alcohol, methyl alcohol, acetone and ketones, and the like, depending on the nature of the pulp, the oxidation water, acidic chemicals and oxidizing or reducing water, basic chemicals and reducing agents can be used. However, since the melting point of the gel is about 60 ° C, the temperature of the extraction solvent is preferably heated to 60 ° C or more.

After elution of the gel extract, bleaching is performed in multiple steps. First, bleaching treatment is performed using ozone. After ozone treatment, the gel extracts dissolved are compressed and removed by pressing at a pressure of 2-10 kg / cm ² , and the ozone treatment is repeated. Ozone treatment is repeated until the color of red alga is over 50 based on whiteness.

After ozone treatment, go through ECF (Element Chlorine Free) process using bleaching with chlorine dioxide or repeat TCF (Total Chlorine Free) bleaching process by further strengthening ozone bleaching process until whiteness is over 60 do.

As a final step in the bleaching process, bleaching with hydrogen peroxide is carried out. When bleaching with hydrogen peroxide, a reducing agent may be added to prepare pulp having a whiteness of 70 or more.

In the present invention, the red algae may be any one or more selected from the group consisting of Locust spruce, Dolphin spree, gambling and Noodle sprouts, but includes all red algae with minimal fiber, It is also possible to use carrageenan or agar obtained.

The fiber extracted from the red algae may be formed in a pulp state suitable for use in a diaphragm, and used in the manufacture of a diaphragm. In this case, the cellulose fiber may be formed to have a sheet structure by forming a network structure through any papermaking process known in the art. However, it is not limited to any particular papermaking process.

The material of the diaphragm of the present invention may be a mixed pulp formed by using only 100% by weight of the fiber extracted from red algae alone or by further mixing wood pulp, chemical pulp or a combination thereof with the fiber extracted from the red algae,

When the mixed pulp is used as the material of the diaphragm, it is preferable that the fibers extracted from the red algae are mixed by 10% by weight or more based on the total fiber weight of the mixed pulp. When the fiber extracted from red algae is mixed by 10% by weight or more, the sound pressure and the original sound reproducibility tend to be excellent.

Wood pulp is generally the most commonly used material for the manufacture of diaphragms, with good sound quality, easy adjustment of properties and low cost. Wood pulp that can be used when preparing such mixed pulp may be used, for example, conifer bleached pulp (NBKP) and Laub Holze Bleached Kraft Pulp (LBKP). .

On the other hand, speakers have recently been adopted in product groups with more diverse applications, and the functions required at this time are also based on acoustical high performance, and the demand for speakers with high reliability such as high heat resistance, high water resistance and durability is expanding. It is becoming. Synthetic fibers, such as aramid fibers, carbon fibers, acrylic fibers and the like, may be used instead of or in combination with wood pulp to meet all of these, but not limited thereto.

When mixing wood pulp or synthetic pulp and fibers extracted from red algae, the wood pulp raw material or synthetic pulp and red algae fibers are dissolved in water in a separate process and mixed by understanding and beating. Figure 1 shows a general flow for mixing wood pulp and red algae pulp, after mixing and mixing with red algae pulp after understanding and beating the wood pulp as can be seen in Figure 1, the process of mixing synthetic pulp Is the same as the red algae pulp. Before processing the natural pulp, the fiber length of the wood pulp is different and the fiber is not uniform, so it is difficult to bond the fiber to the fiber, so the fiber must be mechanically treated in water to make it suitable for papermaking. It is called. Breaking of the fiber is called free beating, and when fibrillation occurs mainly, it is called wet beating. By beating, the fiber outer layer is removed, internal fibrillation occurs, the fiber length is cut, microfibers are formed, and partial dissolution of the chemical composition occurs. The beating makes the fiber flexible and increases the bonds between the fibers, so that as the altitude rises, the paper has a dense structure.

The fiber length of the red algae pulp is about 0.5 to 1.0 mm, whereas the hardwood pulp is about 3 to 4 mm, and the softwood pulp is about 1 to 2 mm, and the width of the pulp is about 2 to 4 μm for the red algae and about 30 to the hardwood pulp. It is ~ 50 μm and about 15-30 μm in coniferous pulp. Red algae fibers have a shorter fiber length, finer fiber diameter, and uniformity than wood fibers. Thus, pulp made of red algae has a more dense structure, higher tensile strength and higher smoothness than wood pulp, resulting in an even surface. Meanwhile, the speaker may be manufactured to have excellent bass or treble performance according to the required specification, and the fiber diameter and length of the red algae are shorter than the wood fibers, and only the fibers extracted from the red algae according to the purpose of the speaker are used to compensate for the disadvantage of the bass. Alternatively, the mixed pulp may be prepared by mixing synthetic pulp or wood pulp with the fibers extracted from the red algae. On the other hand, when the diaphragm is manufactured using only red algae pulp, the beating process may be omitted as shown in FIG. 1.

After understanding and beating wood pulp as described above, red algae pulp and / or synthetic pulp are mixed, after which the altitude is measured after further understanding and further dyeing process, chemical enhancers, water repellents and dyeing agents, etc. Through the processing (Seizing, sizing process) it is possible to produce a paper material suitable for the diaphragm. At this time, it is preferable to use the pure water to be adjusted to pH 7.0, the dye is a direct dye can be used a dye of various colors other than black. Furthermore, a fixing agent for stabilization of dyes, an intelligent agent for increasing the strength of the fiber by increasing the bonding strength of the dye, and a size agent used for improving the waterproofness and the Young's modulus with neutrality, or other raw material properties and uses Depending on the supplement, additional supplements may also be used. On the other hand, the manufacturing method may be performed by any method known in the art, but is not limited to the method.

The diaphragm that can be produced using the red algae-containing pulp of the present invention can obtain a flat frequency characteristic by eliminating the peak in the straight type, high-frequency regeneration characteristics used for woofer or midrange. It can be produced in the form of any known diaphragm, including parabolic diaphragms mainly used for loudspeakers in para-curve and low pass reproduction characteristics, and the shape of the diaphragm is not particularly limited.

The diaphragm for a speaker according to the present invention includes the steps of preparing a pulp using a material containing the fiber extracted from the red algae, and forming the diaphragm using the pulp.

In more detail, the red algae pulp material obtained as described above is imaged using a diaphragm-shaped mesh plate to form a basic shape, and the paper is dehydrated to form a mold. By using a mold (pulp) can be formed into a diaphragm shape by pressing, vacuum molding or heating for a predetermined time. On the other hand, the manufacturing method of the diaphragm may be performed by any method known in the art, it is not limited to the method.

On the other hand, by coating the drug on the surface of the diaphragm made of a pulp material or by further bonding and synthesizing other subsidiary materials, it is possible to manufacture a diaphragm for loudspeakers of higher quality, higher reliability and higher characteristics.

The following examples are intended to describe the present invention in more detail, and the present invention is not limited by the following examples.

Example

Comparison of Characteristics of Red Algae Pulp and Softwood Bleached Kraft Pulp (Soft Pulp NBKP)

To compare the characteristics of red algae pulp and conifer bleached kraft pulp (soft pulp NBKP), conifer bleached kraft pulp (CANADA Western, Squamish-k) was obtained and used as a control. Elastic modulus, internal loss rate, propagation rate and density for mixed pulp mixed with conifer bleached kraft pulp were measured in amounts of 30%, 30%, 50%, 70%, or 100% by weight.

(1) Preparation of Pulp

The mixed pulp is understood by mixing coniferous bleached kraft pulp (CANADA Western, Squamish-k) raw material with pH adjusted to neutral (Ph7.0), and the understood pulp for papermaking (Steel Beater group) Pores)). Then, the red algae pulp is mixed, the raw material is understood as water, and then dyed with a dye (Direct Black ER Conc Special (Ewha Industry)), followed by the addition of a water repellent (Hurex-125 (Taekwang Chemical)) in the blast furnace. Subsequently, it was prepared by adding an intelligence enhancer (water repellent (Hurex-200 (Taekwang Chemical)), at this time prepared by varying only the mixed content of red algae pulp.

(2) Measurement of Pulp Characteristics

The physical properties such as elastic modulus, internal loss, and propagation velocity were measured using a RD-2B type vibration lead type viscoelasticity meter, and the density rule was measured using a density meter and the results are shown in Table 1 below.

division Modulus
(N / m ² ) * 10 Internal loss
(tan δ) Propagation speed
(m / sec) Example 1: 100 wt% NBKP 1.21 E + 0.9 0.048 1300 Example 2: 90 wt% NBKP + 10 wt% red algae pulp 1.57 E + 0.9 0.051 1520 Example 3: 70 wt% NBKP +
Red algae pulp 30% by weight 2.29 E + 0.9 0.055 1736 Example 4: 50 wt% NBKP +
Red algae pulp 50% by weight 2.72 E + 0.9 0.056 1950 Example 5: 100% red algae pulp 3.15 E + 0.9 0.058 2120

As can be seen in the above table, in the case of the mixed pulp added with red algae pulp more than 10% by weight it can be seen that the elastic modulus, the internal loss and the propagation rate are all increased compared to the control. If the elastic modulus of the pulp used in the manufacture of the diaphragm is large, the sound transmission speed is high, the extension of the mid-range is improved, and the internal loss is large, it is possible to reduce the split vibration, and the transient characteristics are improved in the high region.

2. Acoustic Characteristics of Speakers Made Using Diaphragm Containing Red Algae Fiber

(1) manufacture of speakers

Pulps containing red algae fibers were prepared by the same procedure as described in Example (1) of Example 1, and the pulp was cut and molded into a predetermined mold to produce diaphragms, respectively. A 65 mm speaker was manufactured using the diaphragm obtained above.

(2) measuring acoustic characteristics

1W / 50cm using B & K 2012 in Anechoic room of K-TECH Co., Ltd. to evaluate the acoustic characteristics of a speaker manufactured using diaphragm containing red algae fiber together with conifer bleached kraft pulp. The sound pressure in an audible frequency band of 20 Hz to 20 KHz at the distance was measured.

1) Acoustic characteristics of a 65 mm diameter speaker manufactured using a diaphragm composed of mixed pulp containing 10%, 30%, 50%, 70% and 100% red algae fibers with conifer bleached kraft pulp. The acoustic characteristics of a 65 mm diameter speaker composed of conifer bleached kraft pulp at 1 W output (4 Ω, 2 Vrms) were compared as controls.

The results are shown in FIG. 2, and as can be seen in FIG. 2, the speaker manufactured using the diaphragm containing the red algae fibers showed a higher sound pressure than the control group in most audio frequency bands. In FIG. 2, the graph for the diaphragm composed of the mixed pulp containing 10% by weight of red algae fibers is a thin long dashed line (___), and the graph for the diaphragm composed of the mixed pulp containing 30% by weight is a thin solid line ( ), The graph for the diaphragm composed of mixed pulp containing 50% by weight in dashed line ( … ), the graph for the diaphragm composed of mixed pulp containing 70% by weight in thick long dotted line, and the mixed pulp containing 100% by weight. The graphs for the diaphragm consisted of a thick solid line, and the graph for the diaphragm composed of conifer bleached kraft pulp as a control (target) are shown as the center line (_._._.).

1 is a flow chart showing a schematic manufacturing step of mixing pulp mixed with wood pulp and red algae pulp.

2 is a graph showing sound pressure in an audible frequency band of a 65 mm diameter speaker using a diaphragm formed of a material containing 10, 30, 50, 70 and 100 wt% of red algae fibers and a 65 mm diameter speaker using a diaphragm made of wood fiber to be.

Claims

A diaphragm for a speaker formed of a material containing fibers extracted from red algae.

The diaphragm for a speaker according to claim 1, wherein the material of the diaphragm is a pulp of fibers extracted from red algae.

The diaphragm of claim 1, wherein the material of the diaphragm is a mixed pulp formed by mixing at least one pulp selected from the group consisting of wood pulp and synthetic pulp and fibers extracted from red algae.

4. The diaphragm of claim 3, wherein the material of the diaphragm is at least 10% by weight of fibers extracted from red algae based on the total fiber weight of the mixed pulp.

The diaphragm for a speaker according to claim 1, wherein the red algae is at least one selected from the group consisting of wood, wood, gambling, and noodles.

A method of manufacturing a diaphragm for a speaker comprising the step of forming a pulp using a material comprising fibers extracted from red algae, and molding the pulp into the shape of a diaphragm in a mold.

The method of claim 6, wherein the forming of the pulp comprises mixing the pulp extracted from red algae with at least one pulp selected from the group consisting of pulverized wood pulp and synthetic pulp to form a mixed pulp.

8. The method of claim 7, wherein the fibers extracted from the red algae are mixed by at least 10% by weight based on the total fiber weight of the mixed pulp.

The method according to claim 6, wherein the red algae is at least one selected from the group consisting of Locust spruce, Spruce, Gambling, and Noodle sprouts.