A method for controlling the discharge of fluids during a process for vulcanization and moulding of a green tire includes the steps of: building at least one portion of a radially internal surface of a green tire by winding of a continuous elongated element of elastomeric material into a plurality of coils confining circumferential grooves along the rolling direction of the tire; disposing the circumferential grooves into fluid communication with discharge channels present in the radially external surface of a pressing bladder disposed in a radially internal cavity bounded by the green tire.

The present invention relates to compositions in the form of silicone oil emulsions intended to be applied to curing bladders as a mould-release agent during tyre production.

A curing bladder (7) for a tire has a shape of revolution about a central axis and a flexible wall made of crosslinked rubber, the external surface of which is intended to come into contact with the internal surface of a green tire during curing, the external surface having a relief structure having a plurality of air evacuation channels. The relief structure has first channels forming air evacuation grooves (100) arranged at a distance of between 2 and 5 mm, and having a depth of between 0.4 and 1 mm, two adjacent grooves defining, between one another, an inter-groove zone (500) having second channels forming air channelling furrows (1000) made so as to communicate with one another and with at least one of the grooves (100), the furrows each having a depth of between 0.01 and 0.4 mm and being situated at a distance of between 0.2 and 1 mm from one another.

A composition can comprise: an elastomeric composition formed into a curing bladder, the elastomeric composition comprising: 100 parts per hundred parts rubber (phr) of an elastomer comprising a C.sub.4-C.sub.7 isoolefin, a non-halogenated alkylstyrene, and a halogenated alkylstyrene; 1 phr to 7.5 phr alkyl phenol formaldehyde resin; and 0.5 phr to 5 phr mercaptobenzothiazole disulfide. A related method of making a tire curing bladder comprises: mixing 100 phr of an elastomer composition comprising a C.sub.4-C.sub.7 isoolefin, a non-halogenated alkylstyrene, and a halogenated alkylstyrene, 1 phr to 7.5 phr alkyl phenol formaldehyde resin, and 0.5 phr to 5 phr mercaptobenzothiazole disulfide; and molding and curing the mixture into the shape of a tire curing bladder.

Provided is a tire vulcanizing bladder comprising fluororubber, wherein a plurality of grooves extending in a width direction are formed on a circumference of an outer surface of the tire vulcanizing bladder, and a plurality of recesses connecting the grooves to each other are formed between the grooves. Also provided is a pneumatic tire comprising one or more fluorine-containing particles having a maximum diameter of 1.0 μm or more per area of 100 μm.sup.2 of a tire inner surface, wherein a plurality of bladder ridges extending in a tire width direction are formed on a circumference of the tire inner surface, and a plurality of protrusions connecting the bladder ridges to each other are formed between the bladder ridges.

A rubber composition for bladder contains a rubber component containing butyl rubber, a fluorine-based polymer, and a citraconimide compound. When a total amount of the rubber component containing butyl rubber is taken as 100 parts by mass, the fluorine-based polymer is contained in an amount of 0.1 to 2 parts by mass and the citraconimide compound is contained in an amount of 0.2 to 2 parts by mass. It is preferable that the rubber composition for bladder further contains 1 to 10 parts by mass of a sorbitan fatty acid ester. It is preferable that the rubber composition for bladder further contains 1 to 10 parts by mass of a vegetable oil.

A curing bladder (7) for a tire has a shape of revolution about a central axis and a flexible wall made of crosslinked rubber, the external surface of which is intended to come into contact with the internal surface of a green tire during curing, the external surface having a relief structure having a plurality of air evacuation channels. The relief structure has first channels forming air evacuation grooves (100) arranged at a distance of between 2 and 5 mm, and having a depth of between 0.4 and 1 mm, two adjacent grooves defining, between one another, an inter-groove zone (500) having second channels forming air channelling furrows (1000) made so as to communicate with one another and with at least one of the grooves (100), the furrows each having a depth of between 0.01 and 0.4 mm and being situated at a distance of between 0.2 and 1 mm from one another.

A process for manufacturing an ultra-high thermally conductive graphene curing bladder includes the following steps: (1) pre-mixing an ultra-high thermally conductive graphene with rubber to obtain a pre-dispersed graphene master batch, performing a granulation process or a cutting process on the pre-dispersed graphene master batch to obtain a granular solid or a sheet solid, mixing the solid in a rubber mixing mill to obtain an ultra-high thermally conductive graphene rubber compound; (2) extruding, by an extruding machine, the ultra-high thermally conductive graphene rubber compound into a rubber strip of a desirable size; weighing and fixed-length processing the rubber strip of the ultra-high thermally conductive graphene rubber compound to obtain a rubber blank, placing the rubber blank into a pressing type curing bladder mold, closing the mold, pressurizing, heating and curing to obtain a finished product of the ultra-high thermally conductive graphene curing bladder.

The curing bladder for a tire has a shape of revolution around a central axis and comprises a flexible wall made of crosslinked rubber. The surface of the wall is covered with a coating film made of a non-stick composition. When the bladder is non-inflated, the coating film has a variable thickness over the surface.

The present invention relates to compositions in the form of silicone oil emulsions intended to be applied to curing bladders as a mould-release agent during tyre production.