WO-2026094586-A1 - RUBBER COMPOSITION FOR SEISMIC ISOLATION RUBBER LAMINATE, AND SEISMIC ISOLATION RUBBER LAMINATE

Abstract

Provided are: a rubber composition for a seismic isolation rubber laminate, the composition having an excellent effect in suppressing hardening phenomenon; and a seismic isolation rubber laminate.　This rubber composition for a seismic isolation rubber laminate is to be used in a rubber layer of a seismic isolation rubber laminate, and contains the following (A)-(C) components. The contained amount of (B) the component with respect to 100 parts by mass of (A) the component is 10-30 parts by mass.　(A) An isoprene rubber and/or a butadiene rubber. (B) A plasticizing agent having a molecular weight of 300-900. (C) A carbon black that exhibits an DBP oil absorption amount of 100 ml/100 g or more, an iodine adsorption amount of 150 mg/g or more, and a nitrogen adsorption specific surface area of 140 m 2 /g or more.

Inventors

• NAKAICHI SHINGO
• KAJITA YUSUKE
• MURATANI KEIICHI

Assignees

• 住友理工株式会社

Dates

Publication Date

20260507

Application Date

20251009

Priority Date

20241031

Claims (5)

1. A rubber composition for seismic isolation rubber laminates used in the rubber layer of a seismic isolation rubber laminate, A rubber composition for seismic isolation rubber laminates, comprising the following components (A) to (C), wherein the content of component (B) is 10 to 30 parts by mass per 100 parts by mass of component (A). (A) At least one of isoprene rubber and butadiene rubber (B) Plasticizer with a molecular weight of 300 to 900 (C) Carbon black with a DBP oil absorption of 100 ml/100 g or more, an iodine adsorption of 150 mg/g or more, and a nitrogen adsorption specific surface area of 140 m² /g or more
2. The rubber composition for seismic isolation rubber laminate according to claim 1, wherein component (B) is an adipic acid ester-based plasticizer with a molecular weight of 300 to 900.
3. The rubber composition for seismic isolation rubber laminate according to claim 1 or 2, wherein the content of component (C) is 30 to 150 parts by mass per 100 parts by mass of component (A).
4. The rubber composition for seismic isolation rubber laminates according to any one of claims 1 to 3, wherein the component (A) above contains isoprene rubber, and the isoprene rubber content is 70% by mass or more of the total amount of rubber components contained in the rubber composition for seismic isolation rubber laminates.
5. A seismic isolation rubber laminate comprising a rubber layer made of the rubber composition for seismic isolation rubber laminates described in any one of claims 1 to 4, and a layer made of a metal plate.

Description

Rubber composition for seismic isolation rubber laminates and seismic isolation rubber laminates This invention relates to a rubber composition for seismic isolation rubber laminates and seismic isolation rubber laminates. Specifically, it relates to seismic isolation rubber laminates that support structures for civil engineering and construction, and to a rubber composition for seismic isolation rubber laminates used in the rubber layer of such laminates. Traditionally, seismic isolation rubber laminates (rubber bearings) have been used to support structures in fields such as civil engineering and architecture. These seismic isolation rubber laminates are sometimes interposed between the superstructure and substructure of structures such as buildings. Seismic isolation rubber laminates typically have a laminated structure in which rigid plates, such as metal plates, and rubber layers are alternately stacked. Specifically, as shown in Figure 1, for example, the seismic isolation rubber laminate 10 has a structure in which multiple metal plates 14, acting as rigid plates, are embedded at predetermined intervals within a rubber block 12. This results in the alternating, integral stacking of such metal plates 14 and the rubber layers 16, which constitute the rubber block 12, located between the metal plates 14, 14. Furthermore, metal upper mounting plates 18 and lower mounting plates 20 are fixed to the upper and lower parts of the rubber block 12, respectively. When these seismic isolation rubber laminates are installed in the foundation of a building, earthquake tremors are not directly transmitted to the building, the shaking of the upper floors is mitigated, the period of shaking is lengthened, and the desired seismic isolation effect is achieved. This is an explanatory diagram showing a typical example of a seismic isolation rubber laminate.This is a schematic diagram of the apparatus used to perform the evaluation method described in the examples.This figure shows the load-strain loop curve in the evaluation method described in the example. Next, embodiments of the present invention will be described in detail. However, the present invention is not limited to these embodiments. In this specification, "X or/and Y (where X and Y are any configuration)" means at least one of X and Y, and can mean X only, Y only, or X and Y. Furthermore, with respect to the numerical ranges described in stages in this specification, the upper or lower limit of one stage of the numerical range can be arbitrarily combined with the upper or lower limit of another stage of the numerical range. Also, within the numerical ranges described in this specification, the upper or lower limit of that numerical range can be replaced with the values shown in the examples. A rubber composition for seismic isolation rubber laminate according to one embodiment of the present invention (hereinafter sometimes referred to as "this rubber composition") contains the following components (A) to (C), and is characterized in that the content of component (B) is 10 to 30 parts by mass per 100 parts by mass of component (A). (A) At least one of isoprene rubber and butadiene rubber (B) Plasticizer with a molecular weight of 300 to 900 (C) Carbon black with a DBP oil absorption of 100 ml/100 g or more, an iodine adsorption of 150 mg/g or more, and a nitrogen adsorption specific surface area of 140 m² /g or more This rubber composition is characterized by the use of at least one of isoprene rubber and butadiene rubber in combination with a specific carbon black and a specific plasticizer, with the content of the plasticizer controlled within a specific range. By using this rubber composition, a seismic isolation rubber laminate with excellent hardening suppression effect can be obtained. The reason why the above-mentioned excellent effects are obtained with this rubber composition is not entirely clear, but the inventors speculate as follows: A specific plasticizer with a small molecular weight penetrates between the polymer structures of isoprene rubber and/or butadiene rubber. Furthermore, in compounds generally containing carbon black, an insoluble component called carbon gel is formed. This is presumed to be formed by the reaction between polymer radicals generated by molecular scalding during kneading and functional groups on the carbon black surface. While this provides a reinforcing effect through the formation of a network structure, it is also presumed to promote the hardening phenomenon. Therefore, the synergistic effect of the specific plasticizer and carbon black is presumed to effectively suppress the hardening phenomenon by coating the surface of the carbon black with the plasticizer, reducing the amount of carbon gel generated, finely dispersing it, and inhibiting polymer crystallization, thereby keeping the crystallinity of the polymer low. The following provides a detailed explanation of this rubber composition and related information. (A