JPH01163244A - High-density vibration damper - Google Patents

Abstract

PURPOSE:To obtain the title vibration damper with the whole vibration suppressed when used for preventing the resonance of audios to provide high- quality sound, thus suitable as a supporting table for speakers, by blending a polyvinyl chloride paste resin with a plasticizer and lead compound. CONSTITUTION:The objective vibration damper can be obtained by blending (A) 100 pts.wt. of a polyvinyl chloride paste resin with (B) 80-120 pts.wt. of a plasticizer such as dioctyl phthalate and (C) 1,200-2,000 pts.wt. of a lead compound (e.g., lead suboxide, lead dioxide) with a particle size of pref. <=100mum followed by heating and agitation. The resultant blend is formed into a form >=3mm thick, thus obtaining the objective vibration damper.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a high-density damping material. Vibration damping materials are used for the purpose of suppressing imaging by attaching directly to the vibrating surfaces of various machines, piping and ducts, and reducing the sound pressure level radiated from them. It is a type of soundproofing material whose applications are expanding to the fields of transportation equipment, construction materials, etc.

The high-density damping material of the present invention is particularly suitable for speakers, players,
It is useful as a resonance prevention material for audio-related equipment such as amplifiers.

[Conventional technology]

Conventionally, damping materials have generally been made by adding large amounts of mica, graphite, or talc fillers to polymeric materials exhibiting large loss coefficients to increase the specific gravity of the damping material itself.

It is made of polymeric materials, mica, and graphite.

This combination of talc is aimed at achieving a synergistic effect of two weight effects: increasing vibration energy absorption performance, and the heavier the weight, the less likely it is to vibrate. However, the density of conventional damping materials is heavy, around 6, and the maximum is about 4, and it has been considered difficult to achieve a density of 4 or more, especially for damping materials with a wall thickness of 3 or more. Furthermore, up until now, speaker support stands, amplifiers, players, etc. used a large amount of metal-based materials with high specific gravity, with the idea that vibrations were suppressed through weight, and there was a strong belief that luxury products were heavy.

However, such high-density, high-rigidity metal-based materials always have a resonant frequency in the audible frequency range, and there is no way to suppress vibration and improve sound quality by using recent high-density, high-rigidity materials. We are reaching our limits.

[Problem that the invention seeks to solve]

The purpose of the present invention is to solve such conventional problems,
To provide a thick, high-density damping material with high density and excellent damping performance.

[Means for solving problems]

The gist of the present invention is that 80 to 120 parts by weight of plasticizer and 120 to 2000 parts of lead or lead compound powder are added to 100 parts by weight of polyvinyl chloride paste resin.
By blending parts by weight, the density is 59/
It has a high density of d or more, exhibits excellent distribution performance, and has good moldability, making it possible to obtain molded products with a thickness of 3'xs or more, and one side has an elastic modulus of 1Q1.
By reinforcing the button with a net-like fabric made of a material having a value of 1 pa or more, a high-density vibration damping material with improved vibration distribution performance can be obtained.

[Effect]

The polyvinyl chloride base resin used in the present invention is characterized by maintaining fluidity in the form of a sol even when mixed with a plasticizer at room temperature.
A product is obtained by a processing method of heating and forming at a high temperature of about 30°C. Therefore, unlike other thermoplastic polymer materials, it does not require a melt-kneading process. This is a great advantage when a large amount of filler must be blended as in the present invention, since there is no need to take into account wear of equipment during the melt-kneading process. In addition, in order to achieve high density, it is necessary to increase the amount of lead powder filled, but when filling with ordinary fillers such as iron oxide and calcium carbonate, it is about 600 parts by weight per 100 parts by weight of polyvinyl chloride base resin. If the sol is filled with a high loading of 1,200 parts by weight or more, the viscosity of the sol increases and fluidity becomes poor, making it difficult to mold.However, in the case of lead or lead compound powder, even if the sol is filled with a high loading of 1,200 parts by weight or more, sufficient fluidity is obtained. This sol is poured into a mold, heated,
By applying pressure, molded products of various shapes and thicknesses can be obtained. This is a major feature of the present invention. In addition, the content of the polyvinyl chloride base resin in the obtained high-density vibration damping material is 10% or less by weight, and the remaining 90% by weight.
Another feature of the present invention is that although the above components are made up of materials with poor coloring properties, the polyvinyl chloride base resin has excellent coloring properties and can be colored in any desired color. It is.

As the polyvinyl chloride base resin used in the present invention, in addition to ordinary vinyl chloride homopolymers, copolymers of vinyl chloride and various comonomers such as vinyl chloride/vinyl acetate copolymers can also be used.

An example of a plasticizer is dioctyl phthalate.

7-talic acid ester plasticizers such as dihexyl 7-talate and dibutyl phthalate, aliphatic plasticizers such as dioctyl adipate and diisodecyl adipate, phosphate ester plasticizers such as tricresyl phosphate, polyester plasticizers, and epoxy-based plasticizers. Examples include plasticizers and chlorine-containing plasticizers such as chlorinated paraffin. However, it is not limited to the systems listed here.

The amount of plasticizer blended is determined appropriately for the purpose of imparting fluidity when mixed with the total amount of polyvinyl chloride base resin and lead and lead compound powder, but it is usually determined by 80-1 for 7100 parts by weight
The 20th heavy view part is the most important part. If less than 80 parts by weight, sufficient fluidity cannot be obtained, and if more than 120 parts by weight is added, the strength of the material will decrease.

The lead or lead compound powder used in the present invention includes:
Lead metal, lead zinc oxide, lead oxide, lead dioxide.

Examples include dilead trioxide and dilead oxide. Particle size is 100
A thickness of μm or less is desirable. Lead having a particle size exceeding 10,100 t tends to settle quickly in a sol state, and thus lacks sol stability. As for the mixing ratio, it is desirable to have as much lead and lead compound powder as possible from the viewpoint of the purpose, but from the viewpoint of moldability, workability, and strength, adding more than 2000 parts by weight to 100 parts by weight of polyvinyl chloride paste resin will cause it to flow. The properties become poor, making molding difficult, and the strength of the molded product also decreases. Moreover, if it is less than 1200 parts by weight, the density is low (and the effect of suppressing vibrations decreases due to high density).

The shape and size of the high-density damping material of the present invention are determined by the equipment to be used, but the distribution effect of such an unrestricted damping material is 2% relative to the thickness of the base material. If the thickness is twice or more, it is particularly effective, so it is necessary to have a thickness of at least 31Is or more.

The high-density vibration damping material of the present invention is made by blending a polyvinyl chloride paste resin, a plasticizer, and powder of lead or a lead compound, stirring and mixing in a mixer to form a sol, which is preferably defoamed, poured into a mold, and heated and molded. It can be obtained by such methods as Also, if necessary, scaly fillers such as mica, Merck, and graphite, and inorganic fillers such as calcium carbonate and clay.

It can also contain flame retardants and the like.

〔Example〕

EXAMPLES The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Polyvinyl chloride (“Lyuron Paste R-772j
, manufactured by Tosoh Corporation), 68 parts by weight of di-2-ethylhexyl phthalate (DOP, Kao Corporation) as a plasticizer, and dioctyl adipate) (DO
A, 6 parts by weight of Kyowa Hakko Co., Ltd.), 14 parts by weight of chlorinated paraffin (Toyopara Tsukusu 145J, manufactured by Tohoku So Kagaku Co., Ltd.), and a particle size of over 100 μm with metallic lead powder whose surface is oxidized. 1250 parts by weight of non-containing particles having an average particle size of 14 μm were stirred and mixed in a mixer, and the mixture was made into a uniform sol state. The mixture was defoamed in a closed system using a vacuum defoaming machine, and the length was 35 crn.

Width 350. By pouring into a mold with a thickness of 5 mm and heat-forming at a temperature of 180"C for 14 minutes, a plate-shaped high-density damping material of the same size as the mold was obtained.The density of the obtained damping material was 5.
．． It was 297-.

Example 2 The exact same formulation as in Example 1 was used except that 80 parts by weight of di-2-ethylhexyl phthalate (DOP: Kao Corporation M) was used as the plasticizer, and 1800 parts of metallic lead powder was added. The mixture was stirred and mixed using a mixer to form a uniform sol, and the mixture was defoamed using a vacuum defoaming machine in a closed system. The material was poured into a mold having a width of 35-1 and a thickness of 5 squares, and was heat-formed at a temperature of 180° C. for 14 minutes to obtain a plate-like high-density vibration damping material having the same size as the mold. The density of the obtained damping material was 6.097 ad.

Example 3 Using the same formulation as in Example 1, the mixture was stirred and mixed in a mixer to form a homogeneous sol, and the mixture was defoamed in a closed system using a vacuum defoamer. The bottom of a mold with a length of 55cm, a width of 35cm, and a thickness of 5as is woven with fiber diameter 01 seaweed fiber, 909/r.
r? By setting a piece of cheesecloth, pouring the mixture over it and molding it under heat for 14 minutes at a temperature of 180°C,
A plate-shaped high-density damping material with the same size as the mold and reinforced with cheesecloth on one side was obtained. The density of the obtained damping material was 5.19/-.

(Evaluation of vibration allocation effect) Damping performance is determined by fixing one end of a sample made into a rectangular shape, exciting it at the resonant frequency, and during steady imaging, stopping the excitation and allowing free attenuation, and then calculating the loss coefficient from the attenuation behavior. The evaluation was carried out using the cantilever method, which calculates .

The value of the loss coefficient C) is determined from the ratio of the peak intensity values CX) of two adjacent waves in the attenuating wave using the following equation.

The sample obtained in Example 1.2.3 was cut to the same size and adhered to an iron plate having a width of 1.5 cm, a length of 30 cm, and a thickness of 1 inch, and the loss factor was measured. Table 1 also shows the results of only the iron plate as Comparative Example 1.

In all cases of Examples 1, 2, and 3, significant improvements were achieved by combining the iron plate with the iron plate.

Table 1 [Effects of the Invention] As is clear from the above description, according to the present invention, it is possible to obtain a thick vibration damping material with an extremely large specific gravity compared to conventional vibration damping materials. When such high-density damping materials are used to prevent resonance in audio equipment, etc., the weight of the equipment increases significantly, which suppresses the vibration of the entire equipment, and it also absorbs vibration energy by increasing the loss coefficient. This combination of effects suppresses resonance in each part and provides excellent sound quality. It can also be used as a support stand for speakers and players.

Claims (2)

[Claims] (1) 80 to 120 parts by weight of plasticizer and 1 part by weight of lead compound powder per 100 parts by weight of polyvinyl chloride paste resin.
A high-density vibration damping material having a composition containing 200 to 2000 parts by weight and having a thickness of 3 mm or more. (2) The high-density damping material according to claim 1, wherein one side of the damping material is reinforced with a net-like fabric made of a material having an elastic modulus of 10^■Pa or more.