JPS62251131A - Vibration-damping sound-insulating sheet for car - 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] <Industrial Application Field> The present invention provides vibration damping from a vibration damping layer attached to a vehicle panel surface (particularly a floor surface) and a soundproofing layer formed on the vibration damping layer. This invention relates to a vibration damping and soundproofing sheet used to form a soundproofing structure.

<Prior art> Conventionally, the above-mentioned vibration damping and soundproofing structures have been made using rubber-based adhesive compounds (various rubber components, bituminous components,
A damping layer forming material in the form of a sheet made of filler, etc.) is set on the vehicle floor and then heated and softened through a drying oven or the like to blend it with the vehicle floor (vehicle panel) l to form the damping layer 2. Furthermore, the soundproof layer 3 was formed by cutting and pasting a soundproof layer forming material made of felt (poor followability) or the like on the damping layer 2. Note that a mat layer forming material (usually
The mat layer 5 is formed by bonding the carpet (backed carpet). Note that felt herein refers to natural fibers, synthetic fibers, recycled fibers, etc., impregnated with synthetic resins such as phenol resins and vinyl acetate resins, and then hardened into a plate shape.

This vibration damping and soundproofing structure had the following problems.

(A) Formation of the damping layer and the soundproofing layer are separate processes, and the soundproofing layer is formed by cutting and pasting, so the total number of construction steps increases.

(a) Due to the cutting and pasting of felt, there are parts where the soundproof layer is not formed as shown in the example, and the soundproofing effect is not good.

Therefore, in order to solve the above-mentioned problems, the inventors of the present application first created a damping layer forming material made of a rubber-based adhesive compound;
Patent application No. 59-22705 for a vibration-damping and sound-insulating sheet for vehicles having a laminated structure with a sound-insulating layer forming material made of a foamed rubber compound.
This is proposed in the specification attached to the patent application No. 9 (unpublished). The construction of this vibration damping and soundproofing sheet is
Place it on the vehicle panel surface and dry it in a drying oven (heating temperature usually 1.
40-160°C). Then, the damping layer forming material 7 in the state shown in FIG.
The soundproof layer forming material 8 foams to form a vibration damping layer 12 and a soundproof layer 13, respectively (see FIG. 4).

As a technique related to the present invention, Japanese Patent Application No. 60-270101 and 60-158796.15 filed by the present inventors
See No. 8797.158798 (unpublished).

<Problems to be Solved by the Invention> This vibration-damping and sound-insulating sheet can solve the above-mentioned problems, but if there are irregularities on the vehicle panel surface 1, as shown in FIG. , Vehicle, <The soundproof layer forming material 8 and the vibration damping layer forming material 7 fit into the flannel surface shape, and an uneven shape appears on the surface. This is undesirable from the viewpoint of flattening the floor surface, which has been an increasing demand from users in recent years.

In addition, in order to obtain sufficient vibration damping performance only with the damping layer 12 formed from a rubber compound, the sheet must be thick, which leads to an increase in weight and even if it is thick, it is not sufficient at high temperatures. It was difficult to obtain vibration damping performance.

Means for Solving the Problems In order to solve the above-mentioned problems, the inventors of the present invention made extensive efforts in development, and as a result, they came up with a vibration-damping and sound-insulating sheet for vehicles having the following configuration.

A vibration-damping and sound-insulating sheet used to form a vibration-damping and sound-insulating structure consisting of a damping layer attached to a vehicle panel surface and a soundproofing layer formed on the damping layer, the damping layer being an adhesive. It has a two-layer structure consisting of a layer and a constraining layer, and the soundproof layer is made of 1,2-polybutadiene...15 to a5wt1. It is characterized by being composed of a polymer of a foamed rubber compound with a rubber component and a balance.

Detailed Description of the Means> Each configuration of the above means will be explained in detail with reference to an example of a diagram (FIG. 1.2).

(a) The adhesive layer forming material 15 is made by mixing a thermosetting resin, a tackifier, an inorganic filler, a fibrous filler, a softening agent, etc. with a matrix made of various rubber components and bituminous substances, and kneading the mixture with a niegu. , made of extruded material.

(a-1) Rubber components include NR, NBR, IIR,
Various rubbers such as EPDM, EPM, SBR, CR, or a mixture of one or more recycled rubbers thereof are used.

(a-2) As the bituminous component, use one or a mixture of two or more of straight asphalt, blown asphalt, and other natural asphalts. (a-3) For the thermosetting resin, use the above (a-1) rubber component and Use a crosslinking type that can be co-crosslinked. Examples of such thermosetting resins include unsaturated polyester resins, silicone resins, phenol resins, diallyl phthalate resins, melamine resins, and epoxy resins.

Here, the rubber component is NR, SBRlEPDM.

In the case of EPM, BR, fluororubber, silicone rubber, urethane rubber, etc., select an unsaturated polyester resin, silicone resin, diallyl phthalate resin, epoxy-acrylate resin, etc. to be used in combination with an organic peroxide as a curing agent.

In addition, if the rubber component is IIR, NBR, CR, etc.
Select a phenol resin mixed with hexamethylenetetramine, etc.

When such a thermosetting resin is blended, the vibration damping performance of the adhesive layer in a high temperature range is improved. - Use one type or a mixture of two or more types selected from terpene type resins), coumaron type resins (ex, coumaron-based indene resins), natural resins (ex, rosin and rosin derivatives), and phenol φ terpene type resins. .

(a-5) As the inorganic filler, one or two types selected from calcium carbonate, graphite, mica, talc, alumina white, silica, aluminum sulfate, barium sulfate, calcium sulfate, molybdenum disulfide, carbon black, etc. The above mixture is used.

(a-8) As the tlU fibrous filler, glass fiber, asbestos, polyester fiber, nylon fiber, etc. are used.

(a-7) As softeners, process oils (paraffinic, naphthenic, aromatic), phthalate esters (
ex, dioctyl phthalate), fatty acid esters (e
x, dioctyl adipate, dioctyl sebacate),
High molecular weight esters (ex, polyester plasticizer),
One type or a mixture of two or more types selected from epoxidized fatty acids (ex, epoxidized soybean oil), phosphoric acid esters (ex, tricresyl phosphate), etc. is used.

(b) The constraining layer forming material 16 includes (b-1) a thermosetting resin in a semi-cured state, (b-2) a bituminous component added thereto, and (b-3) a rubber component co-crosslinked with it. and (b-4) a matrix consisting of a bituminous component added thereto, a tackifier, an inorganic filler.

It is formed by appropriately blending a fibrous filler and a softener.

(b-1) The following thermosetting resin can be used as a matrix.

It is an unsaturated polyester resin, a silicone resin, a phenol resin, a diallyl phthalate resin, a melamine resin, an epoxy resin, a urea resin, etc., and is capable of co-crosslinking with the rubber component of the adhesive layer forming material 15. The constrained layer forming material 16 is formed by semi-curing these resins. Here, the term "semi-cured" refers to a material that does not show tackiness at room temperature and hardens after being initially softened or fluidized during heat treatment to form a substantially rigid body.

(b-2) A matrix consisting of a semi-cured thermosetting resin component and a bituminous component can be used.

As the thermosetting resin component, those exemplified in (b-t) above are used. As the bituminous component, the above (a) adhesive layer forming material 15 is used.
(a-1) The exemplified bituminous components are used.

That is, it is one or a mixture of two or more of straight asphalt, semi-brown asphalt, blown asphalt, and other natural asphalts.

These matrices (b-1) and (b-2) mainly composed of thermosetting resin in a semi-cured state include (a-4) the tackifier described in the above (a) adhesive layer forming material, and (a- 5)
It is desirable to mix an inorganic filler and (aJ) a fibrous filler.

In addition, the lamination of the constraining layer forming material 16 onto the adhesive layer forming material 15 is not particularly limited, but powdered uncured thermosetting resin is used so that the dry film thickness is 0.05 to 5 m. This is done by sprinkling or applying liquid uncured thermosetting resin.

(b-3) A matrix consisting of a rubber component and a crosslinkable thermosetting resin component that can be co-crosslinked with the rubber component can be used. For example, a rubber component such as NR, EPDM, EPM, and SBR, and a thermosetting resin component such as unsaturated polyester resin, silicone resin, diallyl phthalate resin, and epoxy resin can be used. In this case, an organic peroxide is also used as a curing agent.

Further, examples include those made of a rubber component such as IIR, NBR, and CR, and a thermosetting resin component such as a phenol resin. In this case, hexamethylenetetramine or the like is used in combination as a curing agent.

(b-4) A matrix consisting of a rubber component, a crosslinkable thermosetting resin component co-crosslinkable with the rubber component, and a bituminous component can be used. As the rubber component and thermosetting resin component, those described in (b-3) above are used. As the bituminous component, those described in (b-2) above are used.

The matrices using these rubber components include the above (a)
(a-4) Tackifier described in the adhesive layer forming material.

(a-5) Inorganic filler, (a-8) Fibrous filler, (
a-7) It is desirable to appropriately mix a softener.

Note that the constraint layer forming material 16 using this rubber component is obtained by kneading the above-mentioned materials with a kneader or the like, extruding it, forming it into a sheet shape with a calendar roll, etc., and applying it onto the (a) adhesive layer forming material 15 with a pressure roll or the like. Unify using. The thickness of the constraining layer 21 is desirably thicker, but is usually 0.05 to 10 am, more preferably 0.2 to 5 .mu.m.

(c) Soundproofing layer forming material 18... A foaming agent is added to the polymer, carbon black, zinc white, inorganic filler, softener, tackifier, vulcanizing agent, vulcanization accelerator, etc. It is added and kneaded.

(c-1) As the polymer, as described above, a polymer consisting of 15 to 85 wt% of 1,2-polybutadiene and the remainder of rubber is used. 1.2-polybutadiene is 15
If it is less than wtX, the fluidity during construction (heat foaming) is low and the required surface flatness cannot be obtained. 1.2-When the amount of polybutadiene exceeds 85wt$, the viscosity of the compound becomes low, it is difficult to obtain a highly foamed product due to air release during construction (during heating and foaming), and the fluidity becomes too high, resulting in poor surface flatness. On the contrary, it decreases. In addition, the above 1,2-polybutadiene has a vinyl bond content of 70% or more and a crystallinity of 5%.
and the intrinsic viscosity (η) (in toluene at 30°C) is dl/
go, use 5 or more.

The rubber component is preferably NR, IR, BR, SBR, EPDM, etc., which have good compatibility with 1,2-polybutadiene.

(c-2) The blowing agent may be an inorganic one such as sodium bicarbonate or ammonium carbonate, but it is usually dinitrosopentamethylenetetramine, azodicarbonamide, paratoluenesulfonyl hydrazide, azobisisobutyronitrile, etc. An organic material such as '-oxybisbenzene sulfur hydrazide is usually used. The blending amount is 3 to 10% so that the foaming ratio of the base material is 2 to 10 times.
30 FIR. Further, depending on the blowing agent, it is desirable to use a blowing aid in combination.

(c-3) carbon black, inorganic filler, softener,
Conventional tackifiers, vulcanizing agents, vulcanization accelerators, etc. are used in conventional amounts.

In addition, each of the above-mentioned compositions is usually mixed in a kneader, panburi mixer, etc., and then rolled out or extruded to form a sheet-like soundproof layer forming material 18 (usually 1 to 5 am).

(D) Formation of a vibration-damping and sound-insulating sheet A vibration-damping layer forming material 17 and a sound-insulating layer forming material 18 each consisting of a restraining layer forming material 16 formed on a sheet-shaped adhesive layer forming material 15 are laminated with adhesive, The vibration damping and sound insulating sheet of the present invention.

This pasting work consists of the vibration damping layer forming material 17 and the soundproofing layer forming material 18.
Either separate long pieces are cut into specified dimensions and then laminated together, or when rolled or extruded,
Do it at the same time.

(E) Construction of vibration-damping and sound-insulating sheet The vibration-damping and sound-insulating sheet thus obtained is set on the vehicle panel surface and passed through a drying oven (heating temperature usually 140 to 160° C.). Then, the damping layer forming material is heated and softened, and is then fused to the vehicle panel surface after being adapted to the surface of the vehicle panel by its own weight. At this time, due to the heat of the heat treatment, the thermosetting resin of the constrained layer forming material 16 is crosslinked and cured, and becomes a rigid body to form the constrained layer 21. On the other hand, the adhesive layer forming material 15 becomes the adhesive layer 20. The two-layer damping layer 22 consisting of the constraining layer 21 and the adhesive layer 20 generally exhibits superior damping performance over a wide temperature range, compared to a conventional one-layer damping layer. Furthermore, the soundproof layer forming material 18 is foamed to form the soundproof layer 23 (see FIG. 2). Note that on the upper surface of this soundproof layer 23, a mat layer 5 is provided as in the conventional case.
form.

During this foaming, the soundproof layer forming material 18 exhibits some fluidity, and the surface of the soundproof layer 23 becomes flat as shown in the figure, regardless of the uneven shape of the vehicle panel surface 1.

<Operations and Effects of the Invention> As described above, the vibration damping and sound insulating sheet for vehicles of the present invention includes a damping layer forming material made of a rubber-based viscous compound, and a sound insulating layer forming material made of a foamed rubber compound. By using a blend of a specific amount of 1,2-polybutadiene as the polymer of the foamed rubber compound in adhesively laminated products, there is a slight flow in the soundproof layer forming material during construction (during heat foaming). This makes the surface flat, regardless of the uneven shape of the vehicle panel surface, and can meet the growing demand for flat floor surfaces from users in recent years. Furthermore, the soundproofing layer of the present invention has good open cell properties and improved soundproofing performance, compared to the case where a conventional foamed rubber compound in which the rubber polymer is composed of only rubber is used.

In addition, since the vibration damping sheet consisting of an adhesive layer and a substantially rigid restraint layer is adhered to a metal base such as the vehicle floor in a well-fitted state, the thickness is such that it hardly increases the weight of the vehicle. Good vibration damping performance can be obtained over a wide temperature range.

Note that in the present invention, ethylene vinyl acetate copolymer (EVA) may be used instead of 1,2-polybutadiene, although this has not yet been confirmed, but it is thought that the effects of the present invention can be achieved.

<Example> (1) Rubber compounds having the compositions (expressed in parts by weight) shown in Table 1 below were mixed with a Ni-Goo, and then extruded into sheets with a thickness of 1 kg to obtain each adhesive layer forming material. Ta.

(2) A thermosetting resin compound having the composition shown in Table 2 is applied to the upper surface of the adhesive layer forming material so that the dry film thickness is 1 mm. c) was obtained.

The damping layer forming materials (d, e, f) were obtained by mixing the compositions shown in Table 1 with a Neegoo and extruding them into a sheet having a thickness of 1 m.

Table 1 Table 2 (Unit: Weight (8) (3) In addition, a foamed rubber compound in which the rubber polymer is shown in Table 3 in the following basic formulation is kneaded in a kneader, and the thickness after foaming is 10m. A soundproof layer-forming material was obtained by dividing the material into a predetermined thickness that would become the intestine.

Foamed rubber compound (unit double placement) Rubber polymer lOO zinc white
.

Stearic acid dicalcium carbonate 150 process oil
50 carbon black
20 Sulfur 1.
5 Vulcanization accelerator 2.5 Foaming agent 10 Foaming aid
10(4) The vibration damping layer forming material and sound insulating layer forming material thus obtained were bonded together in combinations shown in Table 3 to form vibration damping and sound insulating sheets of each example and tested for each of the following items. .

In addition, the fourth and fifth comparative examples are vibration damping and sound insulating sheets when only the previously described adhesive layer forming material I is used as the damping layer forming material, and the thickness of each damping layer is 2 am, and 5Il■ in the fifth comparative example.

Test items ■ Sound insulation property... Vibration and sound insulation sheet is placed on a steel plate (240mm x 1
After setting on 50 shoulder straps x 0.8■■t), 150℃ x 3
Test pieces obtained by heat treatment under conditions of 0 minutes were tested.

Specifically, the sample is attached to the opening at the boundary between the sound receiving chamber and the sound source chamber, and the sound pressure in each of the sound source chamber and the sound receiving chamber is The level was measured with a 1/3 octave analyzer via a microphone, and was determined as the difference in sound pressure level between the two chambers.

■Vibration damping properties: Test pieces obtained in the same manner as the sound insulation test at θ℃, 20℃, 40℃, 60℃, 80℃, 100℃
The determination was made using the loss coefficient calculated from the measurement results by the attenuation method in the atmospheres of , and 120°C.

■Followability/Surface flatness...The vibration damping and soundproofing sheets (approximately 700m x 400mm) of each example and comparative example were attached to a corrugated iron plate (
Wave shape; R15+*m, depth 151) upper set,
Heat treatment was performed under the conditions of 150'0 x 30 minutes, and the trackability and surface flatness were visually evaluated. In addition, O...good, ×...poor.

The results of each test are shown in Table 3.

From the test results shown in Table 3, it can be seen that the vibration-damping and sound-insulating sheets of each example have better surface flatness than those of the first to third comparative examples.

In addition, the vibration damping and sound insulating sheets of each example had superior vibration damping performance (especially on the high temperature side) compared to that of Comparative Example 4.5.
It can be seen that it has

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the vibration damping and sound insulating sheet for vehicles of the present invention;
The figure is a cross-sectional view showing the construction mode of the vibration-damping and sound-insulating sheet for vehicles of the present invention, FIG. FIG. 5 is a cross-sectional view showing how the seat is constructed. FIG. 5 is a schematic cross-sectional view of a conventional vibration damping and soundproofing structure for a vehicle. DESCRIPTION OF SYMBOLS 1... Vehicle floor surface (vehicle panel), 15... Adhesive layer forming material, 16... Restriction layer forming material, 17... Damping layer forming material, 18... Soundproofing layer forming material, 20 ...adhesive layer. 21... Restriction layer, 22... Damping layer, 23... Soundproofing layer. Patent application Toyoda Gosei Co., Ltd. Figures 2, 7, 3, 4, and 5!

Claims (1)

[Scope of Claims] A vibration-damping and sound-insulating sheet used to form a vibration-damping and sound-insulating structure consisting of a damping layer attached to a vehicle panel surface and a sound-insulating layer formed on the damping layer. The damping layer has a two-layer structure consisting of an adhesive layer that is attached to the vehicle panel and a restraining layer that is formed thereon, and the soundproof layer is made of the following composition of 1,2-polybutadiene. A vibration damping and sound insulating sheet for a vehicle, characterized in that it is made of a polymer of a foamed rubber compound with a rubber content of 15 to 85 wt%...the remainder.