JPS62132639A - Vibration-damping metallic plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration damping metal plate having vibration damping properties. More specifically, the present invention relates to a damping metal plate used as a damping material for a noise source.

In recent years, noise pollution has become a major social problem, and various measures are being considered to prevent noise. Among these various countermeasures, the use of damping materials for sound sources or parts that generate sound due to vibration is becoming more widespread, and various vibration damping metal plates (hereinafter referred to as vibration damping metal plates) have been proposed so far. There is.

These vibration damping metal plates are required to have the following performance against noise generated from various noise sources.

(1) Demonstrate a high vibration damping effect in the temperature range and resonance frequency range of the operating environment of the various equipment to which it is applied.

(2) If the product is exposed to extremely harsh molding conditions during manufacturing, such as in the oil pan of an automobile, it must have adhesive strength that can withstand such processing conditions.

(3) Welding can be easily performed even in applications that require spot welding or series welding, such as automobile parts.

However, conventional vibration-damping metal plates still have problems from (1) to
It cannot be said that it fully satisfies the required characteristics of (3).
It has been desired to provide a damping metal plate that satisfies all of these properties.

As a result of various studies to solve the problems with the conventional vibration-damping metal plates, the inventors of the present invention added carbon black to the resin layer between the vibration-damping metal plates. It was discovered that excellent performance as a vibration-damping metal plate could be obtained by blending a kneaded material made of a crosslinked elastomer containing the following, and the present invention was completed.

That is, the present invention consists of a plurality of metal plates and a resin layer arranged between the metal plates, and the resin layer contains a kneaded material of a particle size of 300 μm or less made of a crosslinked elastomer containing carbon black to the total weight of the resin layer. The present invention provides a vibration-damping metal plate characterized in that it is blended as a uniform dispersion of 5 to 40% by weight.

The resin used in the present invention is desirably one that has high vibration damping properties over the entire usage environment temperature range from normal temperatures (20°C) to high temperatures (150°C), and has strong adhesive strength to metals, such as EVA resin. , modified EVA resin, ionomer resin, etc. can all be suitably used. Furthermore, the resin itself may not have particularly strong adhesion to a metal plate, and in such a case, the metal surface may be treated with a primer or an adhesive resin such as modified polyolefin may be used to bond the metal plate. It becomes possible to apply resin.

Further, as the dispersion in the resin layer, an elastomer kneaded with carbon black and crosslinked with sulfur or an organic peroxide is used.

Such elastomers include styrene-butadiene rubber (SBR), butadiene rubber (BR), natural rubber (N
R), nitrile rubber (NBR), ethylene propylene rubber (EPR), chloroprene rubber, -3= butyl rubber, isoprene rubber, urethane rubber, etc. are preferably used.

In addition, the carbon black is preferably one having conductivity such as Ketjen black or acetylene black, but HA P (High A brasio) for tire reinforcement is preferable.
n Furnace), E P C (E asy P
rocessingChannel) or the like.

The blending ratio of elastomer and carbon black in such a dispersion is 90/10 to 50,150, preferably 8
It is 0/20 to 60/40.

Further, the dispersion is blended in the resin in an amount of 5 to 40% by weight, preferably 10 to 20% by weight. If the amount is more than this, the shear tensile strength will decrease, while if it is less than this, the T-peel strength will decrease.

Further, since the thickness of the resin layer is generally 50 to 150 μm, the particle size of the dispersion added to the resin is 300 μm or less, preferably 50 to 150 μm. If the particle size is larger than this, it becomes difficult to control the resin film thickness. Further, as the dispersion in the resin layer, a crosslinked rubber powder whose main components are SBR and carbon black and whose composition and properties are almost constant, such as tire rubber powder from waste tires, etc., is preferred from the viewpoint of inexpensiveness and performance.

Further, the metal plates used in the present invention are two or more metal plates stacked on top of each other, but the types of these metal plates are not particularly limited, and these metal plates may be of the same or different types. It's okay to have one. As such metal plates, for example, steel plates (including surface-treated steel plates, stainless steel plates, etc.), aluminum plates, copper plates, etc. are all suitably used.

To manufacture the vibration-damping metal plate of the present invention, first, a dispersion of the elastomer and carbon black kneaded by a conventional method or a crosslinked rubber powder is blended with the resin at a predetermined particle size and blending amount. In order to blend these dispersions or waste tire rubber powder into resin, kneading rolls and kneaders are used.
A device such as the following is used. The thickness of the obtained resin layer was 30
-400I111, preferably 50-150μm
It is.

In thermally bonding the metal plate to the resin layer,
A film-like resin layer may be produced in advance and bonded to the metal plate, or the resin may be melt-extruded directly onto the surface of the metal plate using an extruder or the like, and then thermally bonded.

Therefore, according to the vibration-damping metal plate of the present invention, the following excellent effects can be obtained.

(1) The dispersion containing elastomer as the main component is uniformly dispersed in the resin, which greatly improves the adhesive strength, especially the T-peel strength, and improves the formability of the vibration-damping metal plate, as well as the performance.
In particular, durability is significantly improved.

(2) The thickness of the resin layer of the damping metal plate is usually 50 to 150μ
Since it is about π, the metal plate and the dispersion in the resin layer come into contact with each other, and even a small amount of carbon black can effectively improve the conductivity of the resin, making spot welding, series welding, etc. easier.

(3) The composition and properties are highly stable, and, for example, inexpensive waste tire rubber powder can be used as a dispersion, resulting in excellent performance stability and economic efficiency.

(4) By using an elastomer that is flexible at room temperature as a dispersion, vibration damping properties at room temperature can be improved.

Song Chongsa Next, the present invention will be explained in more detail based on examples.

I will clarify. In the examples, all % means % by weight.

Example I T W L Two cold-rolled steel plates with dimensions of 0.8 x 200 x 250 were used as the metal plates. On the other hand, for comparison, the resin layers were (A) base resin alone, (B) base resin in which a kneaded product of crosslinked elastomer containing carbon black was dispersed (invention), (C), (D) base resin. Four types were used in which elastomer and carbon black were simply dispersed. As the base resin, ionomer resin (Himilan 1652, manufactured by Mitsui Polychemical Co., Ltd.)
Using.

The detailed composition of the resin layer is as follows.

(A) Ionomer resin (100%) (B) Ionomer resin (70%) + WR” (30%)
(C) Ionomer resin (70%) + 5BRA2) (2
14□) +, □□Carbo: /3) (8,67) (D) Ionomer resin (70%) +5BRB4) (2□ 4%
) + H Carbo, 3) (8,6 pieces) (Notes) 1) Waste tire rubber powder, particle size range 0, 3 vutr or less 2) Nippon Zeon Co., Ltd., N1pol 1500, non-oil 3) Mitsubishi Chemical Industries ( manufactured by Nippon Zeon Co., Ltd., Diamond Black, brand 11 4) N1pol l 712, manufactured by Nippon Zeon Co., Ltd.
The oil-extended waste tire rubber powder is a mixture of SBR and carbon black, which is crosslinked by vulcanization, and corresponds to the dispersion of the present invention (B). Waste tire rubber powder usually contains 40 to 50% of HA, F carbon based on the weight of SBH, so for comparison with the rubber powder, non-oil extended (C),
Three representative SBH types of oil-extended (D) were selected, 40% HAF carbon was blended, and a damping metal plate was created by simply kneading these into a resin (resin thickness: 10071 u).

The damping properties of these damping metal plates (A) to (D) were measured in the following manner.

Measurement method: A strip-shaped sample was prepared, and a vibration damping test was conducted using a resonance method using a complex elastic modulus measuring device manufactured by B&N Co., Ltd.

The results are shown in Figure 1. As is clear from Figure 1 (,SB
The damping metal plates (C, D) made by simply kneading R and carbon black are different from the damping metal plates (A) using only base resin.
), the damping properties at room temperature are hardly improved, but the damping metal plate (B) of the present invention, which is kneaded with waste tire rubber powder, has great damping properties at room temperature.

Furthermore, the adhesion between the metal plate and the resin layer of the damping metal plates (A) to (D) was measured.

Shear tensile strength: According to the JIS K6850 method, a test piece of L 35 Xl50 was pulled at a speed of 5 mz/m
Measured at in.

T peel strength: According to JIS K6854 method, W
The speed at which a test piece of L 25 x 150 is pulled! 00mz
/min.

The results are shown in Table 1.

Table 1: Shear tensile strength is 80 kflf/am2 or more when forming automobile oil pans, etc., and T peel strength is 9f at I5.
/25mπ or more'' is required.

From Table 1, it can be seen that all of B-C show a decrease in shear tensile strength, but the decrease is the least in (B), and its value is 44, which is sufficient to meet the minimum standard of shear tensile strength required during molding. I'm adding. On the other hand, regarding the T-peel strength, the vibration damping metal plate (B) of the present invention has an increase of about 3 times that of (A), whereas C) and (D) have the same level as (A). It just has strength.

Furthermore, the conductivity of the resin layers (A) to (D) of the damping metal plate was measured.

Preparation of test piece for conductivity measurement: A 100μ spacer is placed between two steel plates covered with a polyester film for mold release, and a predetermined amount of the resins (A) to (D) are placed between the steel plates. A film was prepared using a hot press machine (molding temperature: 150 to 160° C., molding time: 10 minutes, molding pressure: 30 mm/7 cm2). The obtained resin film was cut into a size of 601φ and subjected to measurement.

Measurement of electrical conductivity: For samples with a volume resistivity of 10°Ω・Qll or higher, measurements were carried out using a high resistance meter made by Yokogawa Hikolet Paracard; ar
Samples in the p range were measured using a digital ohmmeter manufactured by Takeda Riken Kogyo Co., Ltd. and a pressure sheet electrode.

Il- The results are shown in Table 2.

Table 2 From Table 2, the resin layers (C) and (D) are based on the base resin (A
), but the conductivity of the resin layer (B) used in the present invention is significantly higher. This is because when a crosslinked elastomer containing a high concentration of carbon black is dispersed in a resin, a conductive circuit is locally formed and the conductivity increases, but simply kneading SBR rubber and carbon black does not produce this effect. This shows that it will not occur.

Therefore, according to the present invention, a damping metal plate having excellent conductivity and adhesive strength is provided.

[Brief explanation of drawings]

FIG. 1 is a graph comparing the damping properties of the damping metal plate of the present invention with those of other damping metal plates having resin layers.

Claims (4)

[Claims] (1) Consisting of a plurality of metal plates and a resin layer arranged between the metal plates, in the resin layer, a kneaded material of a crosslinked elastomer containing carbon black with a particle size of 300 μm or less is added to the total weight of the resin layer. A vibration-damping metal plate characterized in that it is blended as a uniform dispersion of 5 to 40% by weight. (2) The vibration-damping metal plate according to item (1) above, wherein the elastomer is styrene-butadiene rubber, butadiene rubber, natural rubber, nitrile rubber, ethylene-propylene rubber, chloroprene rubber, butyl rubber, isoprene rubber, or urethane rubber. (3) The vibration-damping metal plate according to item (1) above, wherein the kneaded material is a crosslinked rubber powder. (4) The metal plate is a steel plate, an aluminum plate, a stainless steel plate, a copper plate, or a surface-treated plate thereof.
Vibration-damping metal plate in item 1).