KR19990004254A - Manufacturing method of diaphragm for high performance speaker - Google Patents

Abstract

An object of the present invention is to provide a method for producing a diaphragm for spitzer having excellent elastic modulus and internal loss by vacuum depositing Ti, TiN or TiOx on the surface of a pulp diaphragm mainly composed of cellulose fibers.

The present invention for achieving the above object in the method for producing a diaphragm for a speaker using a pulp mainly made of cellulose fibers in the pulp after adding a paper-making agent to the pulp and dried, and then coated with a synthetic resin, The present invention relates to a method for producing a diaphragm for a high performance speaker which is vacuum-deposited to one selected from titanium (Ti), titanium nitrogen (TiN) and titanium oxylene (TiOx).

Description

Manufacturing method of diaphragm for high performance speaker

The present invention relates to a method for manufacturing a diaphragm for a speaker, and more particularly, to a method for manufacturing a high performance speaker diaphragm having excellent elastic modulus and internal loss.

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

In general, the diaphragm for loudspeakers is caused by distortion due to the material, the edge of the diaphragm and the divided vibration of the body and 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.

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 to reduce the distortion of the diaphragm are made by improving the elastic modulus and internal loss according to the material of the diaphragm.

Theoretical modulus and internal loss can be summarized in more detail as follows.

That is, the most important sound quality and sound frequency characteristics of the speaker are governed by the physical properties of the material constituting the diaphragm, so it is possible to change the sound and frequency characteristics by changing the surface properties of the diaphragm. In order to reproduce a wide frequency range, the surface properties are increased and the inelastic or sound velocity expressed by the following equation is increased.

Inelastic = E / D

C = E / D ^1/2

Where E is the modulus of elasticity, D is the density, and C is the speed of sound.

Therefore, the ideal condition of the diaphragm for the speaker is a high elastic modulus, light material to increase the efficiency is good and there is a difference depending on the use of the speaker, but the internal loss is good.

Conventionally, various methods have been proposed to increase the elastic modulus and increase the internal loss. Among them, for example, a cellulose fiber diaphragm is coated with a synthetic resin to adjust physical properties or to vibrate with a new material to improve sound and frequency characteristics. However, the elastic modulus and the internal loss have properties that are opposite to each other, the higher the elastic modulus, the lower the internal loss, there is a limit to low bass reproduction, the higher the internal loss is difficult to make an ideal diaphragm.

In order to solve the problems described above, the present inventors have repeatedly conducted research and experiment, and the present invention has been proposed based on the results, and the present invention is based on the surface of a pulp diaphragm mainly composed of cellulose fibers. It is an object of the present invention to provide a method of manufacturing a diaphragm for a speaker having excellent elastic modulus and internal loss at the same time by vacuum deposition of TiOx.

1 is a graph showing the change in frequency characteristics according to the frequency band of the conventional wood pulp diaphragm and the Ti deposition diaphragm of the present invention

The present invention for achieving the above object is a method for producing a diaphragm for a speaker using a pulp mainly cellulose fiber, after adding a paper-making agent to the pulp, and then treated with annealing and drying, the synthetic resin coating Next, the present invention relates to a method for producing a diaphragm for a high performance speaker vacuum-deposited into one selected from titanium (Ti), titanium nitrogen (TiN), and titanium oxylene (TiOx). The present invention also relates to a pulp mainly composed of cellulose fibers. In the method of manufacturing a diaphragm for a speaker by using, to the pulp is added to the papermaking agent and less than 30% by weight of ultra-high-density wood pulp to the diaphragm, after the first and dry, coated with synthetic resin, The present invention relates to a method of manufacturing a diaphragm for a high performance speaker which is vacuum-deposited to one selected from titanium (Ti), titanium nitrogen (TiN) and titanium oxylene (TiOx).

Hereinafter, the present invention will be described in more detail.

The present invention can use a pulp mainly composed of cellulose fibers, or a superpulpated wood pulp added to the pulp.

The elastic modulus of the cellulose fibrous paper is determined by the elastic modulus of the short fibers, the fiber length and the contact area between the fibers, and the internal loss is governed by the contact area between the fibers. Therefore, in order to obtain high elastic modulus, it may be advantageous to use a hemp type having a higher short fiber elastic modulus and a longer fiber length than wood pulp. However, in this case, since the fiber length is long, the super-elasticity is lowered and the appearance is deteriorated. Therefore, the amount of the fiber is usually limited to about 5-40% by weight (hereinafter, simply referred to as '%'). For this reason, most commonly use conifer pulp. Coniferous pulp has a shorter fiber length than hemp fiber, but is relatively long and has excellent superelasticity. In the present invention, a pulp mainly composed of cellulose fibers commonly used in this way can be used, and is not particularly limited.

Moreover, in this invention, what added ultra-high-definition wood pulp with a large specific surface area to the pulp mainly cellulose can be used. In order to increase the elastic modulus of the loudspeaker diaphragm, it is necessary to keep the fiber length long so that the pulp fibers are not cut, and to increase the internal loss, it is necessary to increase the interfacial contact area with confession. However, it is difficult to make both compatible in a conventional blast beater because the contact area between fibers increases when blasting progresses, but the elastic modulus does not improve compared to the density increase because the fibers are cut. Therefore, in the present invention, by adding ultra-high-density wood pulp having a large specific surface area to pulp that is not beaten, the elastic modulus and internal loss of the diaphragm for a speaker are simultaneously improved.

At this time, the ultra-high disintegration wood pulp to be added is a wet pulp wood pulp is pressed into the cylinder type blast furnace at high pressure and subdivided along the fiber axis direction, and the specific surface area is preferably 10 m 2 / g or more. In addition, it is preferable to add the amount of ultra-high disintegration wood pulp added to be 30% or less with respect to the total weight of the diaphragm in consideration of the elastic modulus and the negative balance.

In the present invention, the papermaking agent is added to the pulp constituted as described above, and then it is irritated and dried by a conventional method and coated with a synthetic resin.

Coating treatment by synthetic resin improves the adhesion to titanium (Ti), titanium nitrogen (TiN) and titanium oxylene (TiOx), and prevents distortion caused by deposition of different materials, while maintaining the elasticity of the pulp Coating the surface of the diaphragm in a conventional manner. The synthetic resin can be used that is commonly used, it is preferable to use a vinyl-based in order to obtain a more excellent effect in the adhesion, distortion prevention, and the like.

In the present invention, the diaphragm coated with synthetic resin is vacuum-deposited with one selected from titanium (Ti), titanium nitrogen (TiN) and titanium oxylene (TiOx).

The material such as titanium (Ti), titanium nitrogen (TiN), titanium oxylene (TiOx) and the like is a material having excellent elastic modulus. In the present invention, by depositing such a material on the surface of the diaphragm to increase the modulus of elasticity of the diaphragm, the vapor deposition method is not particularly limited and can be carried out according to a conventional method. At this time, the deposition thickness formed by vacuum deposition can be appropriately selected according to the size or capacity of the speaker. However, in consideration of the effect of improving the speed of sound and modulus of elasticity, a thickness of 0.05 µm or more is preferable, and a thickness of 5 µm or less is preferable in consideration of workability and appearance.

Hereinafter, the present invention will be described in more detail with reference to Examples.

(Example 1)

After adding the papermaking agent to the wood pulp dispersed in water, it was fully understood in the understanding. Next, after the initial stage in the initial stage, dehydration, press-drying process, and then coated with a vinyl resin, Ti was vacuum-deposited on the surface to prepare a Ti deposition vibrating plate.

The physical properties of the Ti-deposition vibrating plate manufactured as described above and the pulp diaphragm manufactured by a conventional method are measured and shown in Table 1 below.

TABLE 1

As can be seen from Table 1, the Ti deposition vibration plate according to the method of the present invention can be seen that the sound velocity and elastic modulus are superior to the conventional pulp vibration plate, and the internal loss is also high enough.

In addition, the change in frequency characteristics of the Ti-deposited vibration plate according to the frequency band is measured, and the results are also shown in FIG. 1 together with the characteristic change of the conventional woodpulp diaphragm.

As shown in Figure 1, the speaker diaphragm according to the present invention is excellent in the elastic modulus and the internal loss compared to the conventional woodpulp diaphragm is less distortion, it can be seen that the sound elongation of the high-frequency portion is improved.

(Example 2)

Ultra-high wood pulp was added to the wood pulp in a content as shown in Table 2 below to prepare a pulp diaphragm, and the sound velocity and elastic modulus were measured, and the results are shown in Table 2 below.

TABLE 2

As can be seen in Table 2, the addition of ultra-high-definition wood pulp, the sound speed and modulus were improved. However, when more than 30% by weight was added, the negative balance was broken.

In Table 2, the ultra high-density wood pulp was used for 10% injection, coated with a vinyl resin, and then vacuum-deposited Ti to the thickness as shown in Table 3, and then the sound velocity and elastic modulus were measured. 3 is shown.

TABLE 3

As can be seen in Table 3, by the vacuum deposition of Ti in the thickness range of about 0.05-5㎛, the sound speed and elastic modulus were improved. However, when deposited at less than 0.05㎛, there is little effect of improving sound speed and elastic modulus, and there is almost no effect of improving sound quality. On the contrary, the quality of appearance was also reduced.

According to the present invention as described above, by vacuum-depositing titanium (Ti), titanium nitrogen (TiN) or titanium oxylene (TiOx) on the diaphragm for the speaker using a cellulose fiber-based pulp, while maintaining a high elastic modulus The effect of manufacturing a high performance speaker diaphragm that maintains a high internal loss is provided.

Claims (7)

In the method for producing a diaphragm for a speaker using a pulp mainly cellulose fiber, after adding a paper-making agent to the pulp, the paper is treated with annealing and drying, coated with synthetic resin, and then titanium (Ti), titanium nitrogen (TiN) ), A method of manufacturing a diaphragm for a high performance speaker, characterized in that the vacuum deposition to one selected from titanium oxide (TiOx) The method of claim 1, wherein the synthetic resin is a vinyl-based synthetic resin. The method of manufacturing a diaphragm for a high performance speaker according to claim 1, wherein the deposition thickness formed by the vacuum deposition is 0.05-5 탆. In the method for producing a diaphragm for a speaker using a pulp mainly composed of cellulose fibers, after the addition of ultrafine wood pulp of 30% by weight or less with respect to the paper-making agent and the diaphragm, weed and dried, After coating the synthetic resin, a method of manufacturing a diaphragm for a high performance speaker, characterized in that the vacuum deposition to one selected from titanium (Ti), titanium nitrogen (TiN), titanium oxylene (TiOx). The method of manufacturing a diaphragm for high performance speaker according to claim 4, wherein the ultra-high resolution wood pulp has a specific surface area of 10 m2 / g or more. The method of claim 4, wherein the synthetic resin is a vinyl-based synthetic resin. The method of manufacturing a diaphragm for a high performance speaker according to claim 4, wherein the deposition thickness formed by the vacuum deposition is 0.05-0.5 mu m.