ARTICLE HAVING A ONE-LAYER OR MULTI-LAYER MAIN BODY WITH ELASTIC PROPERTIES, METHOD FOR PRODUCING AN ARTICLE AND USE OF ALUMINIUM HYDROXIDE AS REINFORCING FILLER IN A RUBBER MIXTURE

Abstract

The invention relates to an article, more particularly an air spring bellows, having a one-layer or multi-layer main body with elastic properties, at least one layer of the main body being made up of a rubber mixture, a carbon black proportion of at least one carbon black, more particularly a total carbon black proportion of all carbon blacks, of the rubber mixture being less than 5 phr. The rubber mixture preferably contains aluminium hydroxide as a reinforcing filler. The rubber mixture can comprise chloroprene rubber as a base polymer.

Claims

1-17. (canceled)

18. An air spring bellows (100) having a multi-layered main body (8) having elastic properties, the main body (8) comprising: an inner elastomer layer (3); a middle functional layer (4); and an outer elastomer layer (6); wherein the inner elastomer layer (3), the middle functional layer (4) and the outer elastomer layer (6) are constructed from an identical rubber mixture, in that the rubber mixture comprises aluminum hydroxide as reinforcing filler and in that a total carbon black proportion of all carbon blacks in the rubber mixture is less than 5 phr; and wherein the middle functional layer (4) is in the form of a carcass (13) comprising a cord fabric (7) embedded in at least one ply (5) of an elastomer matrix (9).

19. The air spring bellows (100) of claim 18, wherein the aluminum hydroxide has a proportion in the rubber mixture of 50 phr to 150 phr, in particular of 50 phr to 100 phr, in particular of 100 phr to 150 phr, preferably of 75 phr to 125 phr.

20. The air spring bellows (100) of claim 18, wherein the total carbon black proportion is 0 phr.

21. The air spring bellows (100) of claim 18, wherein the total carbon black proportion is more than 0 phr.

22. The air spring bellows (100) of claim 18, wherein the rubber mixture has at least one colorant added to it, in particular wherein the at least one colorant is a carbon black, an iron oxide or a titanium dioxide.

23. The air spring bellows (100) of claim 18, wherein the carbon black added to the rubber mixture has a BET surface area according to DIN-ISO 9277 which is outside the range from 35 m.sup.2 /g to 140 m.sup.2 /g, and/or the carbon black added to the rubber mixture has an oil absorption number (OAN) according to ISO 4656 which is outside the range from 70 ml/g to 140 ml/g.

24. The air spring bellows (100) of claim 18, wherein the total carbon black proportion of all carbon blacks in the rubber mixture is not more than 4 phr, in particular not more than 3 phr, in particular not more than 2 phr.

25. The air spring bellows (100) of claim 18, wherein the rubber mixture comprises chloroprene rubber or a blend of chloroprene rubber, in particular as the base polymer.

26. The air spring bellows (100) of claim 18, wherein the rubber mixture comprises exclusively aluminum hydroxide as reinforcing filler.

27. The air spring bellows (100) of claim 18, wherein the air spring bellows (100) is a vibration damper and/or a metal-rubber element and/or in that the air spring bellows (11) comprises an air spring bellows membrane (10).

28. A process for producing an air spring bellows (100) having a multi-layered main body (8) having elastic properties, wherein the main body (8) comprises an inner elastomer layer (3), a middle functional layer (4) and an outer elastomer layer (6), wherein the inner elastomer layer (3), the functional layer (4) and the outer elastomer layer (6) are produced from an identical rubber mixture, in that aluminum hydroxide is added to the rubber mixture as reinforcing filler and in that a total carbon black proportion of all carbon blacks in the rubber mixture is less than 5 phr.

29. The process of claim 28, wherein chloroprene rubber or a blend of chloroprene rubber is added to the rubber mixture, especially as the base polymer.

30. The process of claim 28, wherein at least one colorant is added to the rubber mixture, in particular wherein the at least one colorant is a carbon black, an iron oxide or a titanium dioxide.

31. The process of claim 28, wherein no carbon black is added to the rubber mixture.

32. Use of aluminum hydroxide as reinforcing filler in a rubber mixture for forming a main body (8) of an air spring bellows (8), wherein the air spring bellows (8) is configured according to claim 18.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In the figures:

[0043] FIG. 1 shows a longitudinal section through a possible variant of an inventive article, which is here in the form of an air spring bellows, wherein the arrow refers to a detailed view of a section through the layers of the main body of the air spring bellows membrane,

[0044] FIG. 2 is a perspective view of a possible variant of an article which is in the form of an air spring bellows membrane.

DETAILED DESCRIPTION

[0045] FIGS. 1 and 2 each show an article which is as a whole referred to as 100, wherein the working examples shown show an air spring bellows 11 and an air spring bellows membrane 10.

[0046] Article 100 comprises at least a main body 8 which is elastic at least in part and is therefore deformable.

[0047] The main body 8 at least partially delimits an air chamber 12.

[0048] Article 100 may further comprise at least two reinforcing elements, in particular made of metal, which may be in the form of metal cores for example. The reinforcing elements may be adapted for joining, in particular by screw connection and/or clamping and/or push-fitting, the article to further components.

[0049] The article 100 comprises two beads 2 which are each reinforced by a bead core 1. The air spring bellows membrane 10 extends between the two beads 2 and forms on its inside an air chamber 12.

[0050] The main body 8 is constructed from a plurality of layers 3, 4, 5, 6, 9 which may be at least partially or completely crosslinked with one another to form a composite element. This can especially prevent relative motion between the individual layers 3, 4, 5, 6, 9.

[0051] At least one layer 3, 4, 5, 6, 9 of the main body 8 is formed from a rubber mixture having a carbon black proportion, in particular total carbon black proportion, of less than 5 phr. It may be provided that all layers are formed from that rubber mixture. As a consequence of being formed from the same rubber mixture the layers form a homogeneous rubber matrix.

[0052] The carbon black proportion may be for example a carbon black proportion of any carbon black or else of a carbon black having a BET surface area according to DIN-ISO 9277 of 35 m.sup.2/g to 140 m.sup.2/g an/or an oil absorption number (OAN) according to ISO 4656 of 70 ml/100 g to 140 ml/100 g.

[0053] An addition of carbon black is merely for the purpose of adding the carbon black as colorant to achieve black coloring of the main body 8. If the article 100 is to have a different coloring the carbon black may also be substituted by a different colorant. If coloring is to be dispensed with the carbon black/the colorant may be omitted. This does not alter the elastic and mechanical properties of the rubber mixture.

[0054] The main body 8 comprises an inner elastomer layer 3, a middle functional layer 4 and an outer elastomer layer 6. In particular at least the outer elastomer layer 6 and/or the inner elastomer layer 3 may comprise a carbon proportion in an amount of less than 5 phr. It is preferable when all layers 3, 4, 5, 6, 9 of the main body 8 each have a carbon black proportion in an amount of less than 5 phr.

[0055] The middle functional layer 4 may be in the form of a carcass 13. In the variant shown the middle functional layer 4 comprises at least one cord fabric 7 which is in each case embedded in two or more plies 5 of an elastomer matrix 9. The elastomer matrix 9 may be formed from two or more plies 5 of the rubber mixture further described hereinabove and hereinbelow.

[0056] The at least one layer 3, 4, 5, 6, 9 may comprise chloroprene rubber or a blend of chloroprene rubber and another rubber as the rubber component. The rubber component is preferably made exclusively of chloroprene rubber.

[0057] The rubber mixture of the at least one layer 3, 4, 5, 6, 9 further comprises aluminum hydroxide as reinforcing filler, wherein aluminum hydroxide also functions as flame retardant. What is novel here is especially the surprising finding that aluminum hydroxide can replace carbon black as reinforcing filler. Aluminum hydroxide thus has a dual function as flame retardant and as reinforcing filler. In particular, the rubber mixture may include an amount of ATH of 50 phr to 150 phr, in particular of 60 phr to 140 phr, in particular of 70 phr to 130 phr.

[0058] The at least one layer 3, 4, 5, 6, 9 is preferably at least the outer elastomer layer 6.

[0059] In addition to being in the form of an air spring bellows membrane 10 and/or air spring bellows 11, the article 100 may be in the form of a vibration damper and/or a metal-rubber element. The article 100 may in particular be in the form of a damping element of a mounting and/or a conical spring and/or a sandwich mount.

[0060] It is generally the case that a reinforcing filler makes it possible to produce a particle-filled polymer, wherein an increase in elastic modulus is achieved according to a filler volume fraction. It is therefore necessary that a certain proportion of such fillers is used in the production of elastomers to adjust hardness, abrasion resistance and crack resistance characteristics.