摘要:
A layer of cellular material forms a running layer (14A) of a tread (14) in which tread pattern elements (20, 22, 26) are made. In order to form the cellular material, an uncured blank is provided with a mass of material comprising p,p′-oxybis(benzenesulphonyl hydrazide) that forms a pore-forming agent. The uncured blank is placed in a vulcanization mold (28) comprising molding elements (30, 32, 34). At least 95% of the molding elements (30, 32, 34) each satisfy the following two conditions: a) the molding element (30, 32, 34) is separated from at least one other molding element (30, 32, 34) by a distance, expressed in millimeters, of less than or equal to DM=6.85+0.0065T3, T, greater than or equal to 3 phr, being the amount of p,p′-oxybis(benzenesulphonyl hydrazide) in the mass of material intended to form the cellular material, b) the molding element (30, 32, 34) is intended to form a tread pattern element (20, 22, 26) having a depth at least equal to 80% of the thickness of the running layer (14A).
摘要:
A tyre, the tread of which comprises a rubber composition comprising at least: a diene elastomer; from 100 to 150 phr of a reinforcing inorganic filler; a poly(alkylene ester) thermoplastic resin; a plasticizing system comprising: according to a content A of between 5 and 60 phr, a hydrocarbon resin exhibiting a Tg of greater than 20° C.; according to a content B of between 5 and 60 phr, a plasticizer which is liquid at 20° C., the Tg of which is less than −20° C.; and it being understood that A+B is greater than 40 phr. The use of a poly(alkylene ester) resin, combined in particular with high contents of filler and plasticizers, makes it possible to improve the stiffness of the tread and thus the road behaviour of the tyre, without affecting the hysteresis and thus the rolling resistance.
摘要:
The tire (10B) comprises a tread (12) including a running layer (14) which is intended to come into contact with the ground when the tire (10B) rolls on the ground, and a sublayer (16) located radially inwards from the running layer (14). The tread (12) comprises at least one fluid passage (22) between the sublayer (16) and the air surrounding the tire (10B). The sublayer (16) comprises a cellular material. The fluid passage (22) comprises an element chosen from a groove (20) and a cut (26), formed in the running layer (14) and extended by at least one well (28) acting as a radial extension of the element, formed between the groove (20) and/or the cut (26) and the sublayer (16). Each well (28) forms a localized part of the fluid passage (22).
摘要:
The tire (10B) comprises a tread (12) including a running layer (14) which is intended to come into contact with the ground when the tire (10B) rolls on the ground, and a sublayer (16) located radially inwards from the running layer (14). The tread (12) comprises at least one fluid passage (22) between the sublayer (16) and the air surrounding the tire (10B). The sublayer (16) comprises a cellular material. The fluid passage (22) comprises an element chosen from a groove (20) and a cut (26), formed in the running layer (14) and extended by at least one well (28) acting as a radial extension of the element, formed between the groove (20) and/or the cut (26) and the sublayer (16). Each well (28) forms a localized part of the fluid passage (22).
摘要:
A vehicle tyre includes a tread formed of a rubber composition that is heat-expandable when unvulcanized, and expanded when vulcanized. When unvulcanized, the composition includes from 50 to 100 phr of a copolymer based on styrene and butadiene; optionally from 0 to 50 phr of another diene elastomer, such as a polybutadiene or a natural rubber; more than 50 phr of a reinforcing filler, such as silica and/or carbon black; between 5 and 25 phr of a sodium- or potassium-including carbonate or hydrogencarbonate; and between 2 and 15 phr of a carboxylic acid having a melting point between 60° C. and 220° C., such as citric acid. A total content of the carboxylic acid and the carbonate or the hydrogencarbonate is greater than 10 phr. Presence of the carboxylic acid and the carbonate or the hydrogencarbonate makes it possible to significantly reduce noise emitted by the tyre during running.