JPH0447072B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a sound insulating material with excellent flexibility, soundproofing properties, and workability. BACKGROUND OF THE INVENTION Various types of sound insulating materials for preventing external noise from entering or radiating to the outside, and sound absorbing materials for weakening sound reflection, are known. It has a high areal density and can be processed into a sheet and laid on the floors and walls of automobiles, railway vehicles, and buildings, adhered to uneven or curved surfaces, or used as a composite material by laminating it with steel plates or nonwoven fabrics. Moreover, it is important that it has good flexibility and good moldability.
In addition, price, availability of materials, and resistance to deterioration are also important. In order to improve the sound insulation effect, it is desirable to increase the areal density as much as possible, that is, to fill as much high-density filler as possible. However, the affinity between the binder and filler is related to each other, and if the binder and filler are not properly combined, a plate-out phenomenon will occur during molding and the surface finish of the product will deteriorate. Recently, Japanese Patent Laid-Open Publication No. 34064/1983 discloses a soundproofing material that combines a vinyl chloride resin containing a plasticizer with iron oxide, which is a by-product of the steel manufacturing process. Although this oxide is said to have excellent adhesion with vinyl chloride, it has poor peelability from the roll surface during molding.
The gelation time is also long, and the mechanical properties of the resulting sheet are not sufficient. Flexible sound insulating materials can not only be placed closely on curved surfaces, but also exhibit vibration absorption and sound insulating effects without resonance. For this purpose, the flexural modulus is small,
It must have the ability to withstand bending (flexibility). Problems to be Solved by the Present Invention After repeated research into manufacturing a sound insulating material with excellent flexibility and high areal density with good workability, the present inventor found that iron and steel slag particles, which are by-products of the copper smelting process, is an extremely excellent filler, and upon further research, we found that appropriate selection of iron ferrite, silica, and solid alkali completely satisfies all of the above objectives, leading to the completion of the present invention. I've reached it. Structure of the invention The present invention uses vinyl chloride resin as a binder,
In the sound insulation material formed by mixing inorganic powder as a filler with this, (a) the filler is iron oxide 50
-90% by weight, 10-30% by weight of silica, and a total of 10% by weight or less of alkali or alkaline earth metal oxides, (b) 200-1700 parts by weight of the filler per 100 parts by weight of the binder. This is a flexible sound insulating material that is kneaded and molded. The details will be explained in more detail below. The basic components of the sound insulation material of the present invention are vinyl chloride and inorganic powder. Functionally, the former is a binder,
The latter is called a filler. The filler used in the present invention is particularly important in its constituent components and proportions. That is, the filler is iron oxide 40
~85wt% and at least 10wt% silica,
On the other hand, the total amount of alkali or alkaline earth metal oxides is 10 wt% or less. There are no particular restrictions on the composition of the remainder. Iron oxides include FeO, Fe ₂ O ₃ , Fe ₃ O ₄ , FeO・Fe ₂ O ₃ ,
It includes those existing in various forms of nFeO.SiO ₂ (n is 1 to 3). In particular, iron oxide, which exists as nFeO・SiO ₂ , is separated from FeO and SiO ₂ in normal quantitative analysis.
Here, FeO is regarded as iron oxide because it can be quantified separately. The proportion of iron oxide to the total filler is present in the range of 50-90 wt%. If the proportion of iron oxide is low, sufficient sound absorption properties cannot be exhibited. The upper limit is determined from the required amount of silica, which is another essential component. Another essential filler component is silica. The bulk specific gravity of this component itself is around 0.1, which is smaller than that of iron oxide, which is 4 to 6, so silica does not help improve the areal density, but its presence increases the amount of iron oxide that can be filled. Furthermore, it is effective in preventing the plate-out phenomenon during molding, shortening the gelation time, and improving the smoothness of the product. From the viewpoint of filling a large amount of the front and rear iron oxide fillers, it is preferable that silica is present in the filler at least 10 wt% or more, preferably 10 to 30 wt%. In addition to SiO ₂ , silica includes nFeO・SiO ₂ , nFeO・
Any form of Fe ₂ O ₃ ·SiO ₂ (n=1 to 3) or silica alumina may be used. For example, a catalyst for catalytic cracking of petroleum is preferably a silica-alumina powder. Although a large amount of silica may be contained, as mentioned above, it is not preferable to use a large amount because it limits the content of iron oxide and has a low density. Therefore, the upper limit may be 30wt%. Especially nFeO・
Iron and steel slag, which is a by-product of the copper smelting process and mainly contains SiO ₂ , is most preferred as a filler. Oxides of alkali or alkaline earth metals in the filler used in the present invention, specifically Na ₂ O,
The smaller the amount of MgO and CaO, the better, and the upper limit is 10wt.
% or less, preferably 5 wt% or less. If the oxide is present in a large amount, a plate-out phenomenon will occur on the roll metal surface during molding, and the gelation time will be delayed. Furthermore, the presence of this component inhibits the effectiveness of silica. In addition to the above, fillers such as carbon,
Fine particles of lead, copper, zinc, zinc oxide, titanium oxide, carbonate, etc. may be present. These particles also have increased affinity with the binder by using the filler. An example of a filler that satisfies the above composition is to convert matte obtained from a flash furnace in the copper smelting process into a converter.
So-called iron is obtained by adding SiO ₂ and oxygen to perform silicate formation and oxidation, magnetic separation of the resulting slag, flotation of the resulting slag, and dehydration of the residue after recovering copper concentrate. It is concentrate slag. A specific example of the composition of the slag is 2FeO・SiO ₂ (40~
50wt%, 15~30wt% as _SiO2 ), _{Fe3O4 10} ~
30wt%, Fe ₂ O ₃ 5wt%, MgO 5% or less, almost no CaO. That is, it contains sufficient amounts of iron oxide and silica, while containing almost no alkali metal oxide.
Since the composition is a by-product of the copper refining process, it is inexpensive and produced in large quantities. Moreover, since it has undergone flotation, it is originally crushed particles. This slag has a bulk density of 3 to 4 and a true specific gravity of 5 to 5.5. Therefore, it can be said that it is a preferable filler. Since moisture in the filler causes foaming during the molding process, 3wt.
% or less, preferably 2wt% or less, particularly preferably
It is best to use it after drying to less than 1wt%. On the other hand, converter slag generated in the steel manufacturing process is
-As stated in Publication No. 3406, it contains 25wt% iron oxide, 12wt% silica, and about 37wt% CaO.
The composition is completely different from that of the iron concentrate slag generated in the copper smelting process. The filler used in the present invention and the converter slag produced in the steel manufacturing process are significantly different in affinity with vinyl chloride resin and processability. This will become clear in the examples described later. In the present invention, the filler is mixed with the vinyl chloride resin in fine particles of 100, preferably 200 mesh under. The above-mentioned fillers have extremely good affinity with these binders, and flexibility can be maintained even when a large amount of filler is filled with a small amount of binder. As the vinyl chloride resin, polyvinyl chloride and a copolymer of vinyl chloride and vinyl acetate can be used. Add plasticizers and stabilizers during use. Covering materials recovered from waste cables, used agricultural and agricultural vinyl chloride sheets, etc. can also be preferably used. Natural rubber as an adjunct to the above vinyl chloride resin,
Styrene-butadiene rubber, such as used automobile tires, may also be blended. The vinyl chloride resin has an exceptional affinity with the filler, and the amount of filler per 100 parts by weight of binder is
It is mixed in a proportion of 200 to 1700 parts by weight. The sheet-like product obtained does not crack when bent. To produce the flexible sound insulating material of the present invention, appropriate amounts of a plasticizer and a stabilizer are blended into a binder, and the filler is further blended, heated to about 100 to 150°C, stirred, and sufficiently kneaded using a mixing roll or the like. Since the sound insulating material of the present invention is used in the form of a sheet, it can be finished to a thickness of about 0.2 to 10 mm using a calendar molding machine or an extrusion molding machine. The sheet is
It can be used as is or by pasting it onto a steel plate, nonwoven fabric, etc. The following will be explained based on examples. Examples 1, 2, 3 100 parts by weight of vinyl chloride resin, as a plasticizer
600 parts by weight of each of the fillers shown in Table 1 were mixed with 165 parts by weight of a compound containing 60 parts by weight of DOP and 5 parts by weight of a tin-based stabilizer, and kneaded. 8
A 2 mm thick sheet was produced using two inch x 20 inch rolls. The evaluation results of workability are shown in Table 2.

【table】

【table】

[Table] From Table 2, filler F- containing a large amount of CaO
2. When F-3 or filler F-4, which has too little silica content, is used, the plate-out phenomenon is significant, the gelation time is doubled, and the bending resistance is weak. It will be understood that all of these have excellent performance. Examples 4, 5, 6 Fillers shown in Examples 1 to 3 (F-1, F-
Sheets were produced by changing the blending amount of 2) and molding in the same manner. The results are shown in Table 3.

【table】

[Table] Effects of the present invention The sound insulating material of the present invention is a sound insulating material that uses a filler whose main component is iron oxide and has an extremely high areal density. It has superior moldability compared to conventionally proposed products, maintains good flexibility and bending resistance even when filled with a large amount of filler, and can be manufactured using inexpensive raw materials. In addition to the above-mentioned uses, the sound insulating material of the present invention is also suitable for uses such as the operation console of a printer of OA equipment, the interior of a printer's soundproof case, etc., since it also has antistatic properties.

Claims (1)

[Scope of Claims] 1. A sound insulation material that is kneaded and molded using a vinyl chloride resin as a binder and inorganic particles as a filler, (a) The filler contains 50 to 90% by weight of iron oxide and 10% by weight of silica.
~30% by weight, a total of 10% by weight or less of alkali metal oxides or alkaline earth metal oxides, and (b) 200 to 1700 parts by weight of the filler is blended to 100 parts by weight of the binder. A flexible sound insulating material featuring: 2. The flexible sound insulating material according to claim 1, wherein the total amount of alkali metal oxides or alkaline earth metal oxides in the filler composition is 5% by weight or less. 3 All or part of the silica is nFeO.
The flexible sound insulation material according to claim 1 or 2, which is present as _SiO2 (n is 1 to 3). 4 Iron oxides are FeO, Fe ₂ O ₃ , Fe ₃ O ₄ , nFeO・SiO ₂
The flexible sound insulating material according to any one of claims 1 to 3, wherein n is any one or two or more of the following: (n is 1 to 3). 5. The flexible sound insulating material according to any one of claims 1 to 4, wherein the filler is iron concentrate slag produced as a by-product in a copper smelting process. 6. The flexible sound insulating material according to any one of Claims 1, 1 to 5, wherein the filler has a moisture content of 2 wt% or less.