JP2019111661A - Bladder for tire vulcanization, and pneumatic tire - Google Patents

Abstract

To provide a bladder for tire vulcanization having enhanced durability, and enhance quality of tire inside of a pneumatic tire manufactured by using the bladder for tire vulcanization.SOLUTION: A bladder for tire vulcanization consists of a fluorine rubber, in which a plurality of grooves extending in a width direction are formed on a circumference of an outer surface of the bladder for tire vulcanization, 5 or more grooves are formed per 1 inch in a circumferential direction at any position of the width direction on the outer surface, at a state that the are pushed to an inner surface of the unvulcanized tire. The pneumatic tire has one or more particle containing fluorine with maximum diameter of 1.0 μm or more per region of 100 μmof the tire inner surface, in which a plurality of bladder ridges extending in a tire width direction are formed on the circumference of the outer surface of the tire, and 5 balder ridges are formed per 1 inch in the tire circumferential direction at ant position of the tire width direction of the tire inner surface.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a tire vulcanizing bladder and a pneumatic tire.

  The process of manufacturing a pneumatic tire (hereinafter, also simply referred to as a tire) includes a process of vulcanizing a green tire (unvulcanized tire). In this vulcanization process, a green tire incorporating a tire component is usually placed in a tire vulcanization mold, and the inner cavity of the green tire is further referred to as a tire vulcanization bladder (hereinafter simply referred to as a bladder). A rubber bag is inserted, which consists of a cylindrical ring of circular or horseshoe-shaped cross section. Next, a shaping gas is introduced into the bladder, shaping is performed to bring the inner surface of the green tire into close contact with the bladder, and then high temperature steam such as high temperature steam or high temperature inert gas such as high temperature nitrogen gas inside the bladder. be introduced. As a result, the green tire is strongly pressed against the inner surface of the vulcanizing mold and heated from the inside of the green tire. At the same time, heating is also performed from the outer surface of the green tire by heating the vulcanizing mold with high temperature steam or the like, and vulcanization molding of the tire is performed.

  As such a tire vulcanizing bladder, it is common to use a bladder made of butyl rubber (see, for example, Patent Document 1). Here, butyl rubber chemically reacts with the rubber of the green tire inner surface member in contact with the bladder and adheres. For this reason, when performing a vulcanization | cure process using the bladder which consists of butyl rubber, coating the mold release agent containing a silicon | silicone and a talc on a green tire inner surface is performed.

  However, since a coating machine is used to coat a mold release agent on the inner surface of a green tire, there are problems such as the consumption of materials such as operation energy and coating liquid, and the need to secure an operator's hand. The

  On the other hand, it has also been proposed to use a tire vulcanizing bladder made of fluorine rubber. Since the fluorine rubber does not react chemically with the green tire inner surface member, it is not necessary to coat the inner surface of the green tire with a release agent.

JP, 2014-184579, A

  However, due to the nature of the fluororubber, there is a problem that when the use is repeated, cracks occur in the groove and the durability is lowered. In addition, there is a problem that a tire vulcanized using a bladder in which a crack is generated in a groove may have its state transferred to the inner surface of the tire and the appearance may be impaired.

  Then, this invention aims at providing the bladder for tire vulcanization which improved durability, and improving the quality of the tire inner surface of the pneumatic tire manufactured using this tire vulcanization bladder.

The essential features of the present invention are as follows.
The tire vulcanizing bladder of the present invention is made of fluoro rubber,
A plurality of grooves extending in the width direction are formed on the circumference of the outer surface of the tire curing bladder,
When pressed against the inner surface of the unvulcanized tire, the groove portions are formed at 5 or more per 1 inch in the circumferential direction at any position in the width direction on the outer surface.
According to the tire vulcanizing bladder of the present invention, the durability of the tire vulcanizing bladder can be improved, and the quality of the tire inner surface of the pneumatic tire manufactured using the tire vulcanizing bladder can be improved. .
Here, the “groove” means one having a depth (maximum depth) of 0.3 mm or more.

In the tire vulcanizing bladder of the present invention, when the gauge of the tire vulcanizing bladder is A (mm) and the depth of the groove is B (mm), the ratio B / A is
0.03 ≦ B / A ≦ 0.15
It is preferable to satisfy
By setting the above range, the durability of the tire vulcanizing bladder is further improved, and the quality of the inner surface of the tire of the pneumatic tire manufactured using the tire vulcanization bladder is further improved. it can.
Here, "gauge" refers to the largest gauge, and "depth" refers to the largest depth.

In the tire vulcanization bladder of the present invention, when the width of the groove is C (mm) and the depth of the groove is B (mm), the ratio B / C is
0.3 ≦ B / C ≦ 1.0
It is preferable to satisfy
By setting the above range, the durability of the tire vulcanizing bladder is further improved, and the quality of the inner surface of the tire of the pneumatic tire manufactured using the tire vulcanization bladder is further improved. it can.
Here, "the width of the groove portion" means the width between the middle point of the extension direction of the two inflection points of one side wall of the groove portion and the middle point of the extension direction of the two inflection points of the other side wall. It refers to the distance in the direction.

In the tire vulcanizing bladder of the present invention, the ratio B / D is, where D (pieces) is the number of the groove portions on the entire circumference and B (mm) is the depth of the groove portions,
0.001 ≦ B / D ≦ 0.006
It is preferable to satisfy
By setting the above range, the durability of the tire vulcanizing bladder is further improved, and the quality of the inner surface of the tire of the pneumatic tire manufactured using the tire vulcanization bladder is further improved. it can.

In the tire vulcanizing bladder of the present invention, when the radius of curvature of the corner of the bottom of the groove in the cross section in the extension direction of the groove is E (mm) and the depth of the groove is B (mm) , Ratio B / E,
1.0 ≦ B / E ≦ 5.0
It is preferable to satisfy
By setting the above range, the durability of the tire vulcanizing bladder is further improved, and the quality of the inner surface of the tire of the pneumatic tire manufactured using the tire vulcanization bladder is further improved. it can.

In the tire vulcanizing bladder of the present invention, it is preferable that a plurality of concave portions connecting between the groove portions be formed between the groove portions.
According to this configuration, the durability of the tire vulcanizing bladder can be further improved, and the quality of the tire inner surface of the pneumatic tire manufactured using the tire vulcanization bladder can be further improved.

The pneumatic tire of the present invention has one or more particles containing fluorine having a maximum diameter of 1.0 μm or more per 100 μm ² of the inner surface of the tire,
A plurality of bladder ridges extending in the tire width direction are formed on the circumference of the inner surface of the tire,
The number of the bladder ridges may be five or more per one inch in the tire circumferential direction at any position in the tire width direction on the inner surface of the tire.
The pneumatic tire of the present invention is excellent in the quality of the inner surface of the tire.
Here, "bladder ridge" refers to one having a height (maximum height) of 0.3 mm or more under atmospheric pressure.

In the pneumatic tire according to the present invention, when the width of the bladder bridge is C ′ (mm) and the height of the bladder bridge is B ′ (mm), the ratio B ′ / C ′ is
0.3 ≦ B ′ / C ′ ≦ 1.0
It is preferable to satisfy
By setting it as said range, the quality of tire inner surface will become still more excellent.
Here, “width” means the middle point of the extension direction of the two inflection points of one side wall of the bladder ridge under the atmospheric pressure and the extension direction of the two inflection points of the other side wall The distance in the width direction to the point is referred to, and “height” refers to the maximum height under atmospheric pressure.

In the pneumatic tire according to the present invention, the ratio B '/ D' is, where D '(pieces) is the number of the bladder ridges on the entire circumference and B' (mm) is the height of the bladder ridges,
0.001 ≦ B ′ / D ′ ≦ 0.006
It is preferable to satisfy
By setting it as said range, the quality of tire inner surface will become still more excellent.

In the pneumatic tire according to the present invention, when the radius of curvature of the corner of the top of the bladder bridge is E ′ (mm) and the height of the bladder bridge is B ′ (mm), the ratio B ′ / E ′ is
1.0 ≦ B ′ / E ′ ≦ 5.0
It is preferable to satisfy
By setting it as said range, the quality of tire inner surface will become still more excellent.

In the pneumatic tire according to the present invention, a plurality of convex portions connecting the bladder ridges are formed between the bladder ridges, and the convex portions attach the tire to the rim, fill the prescribed internal pressure, and are not loaded. In the state, it is preferable that the tire outer contour from the tread surface to the tire maximum width position be formed only from the inner surface of the hump portion to the inner surface of the bead portion, which is a region having the smallest curvature radius.
According to this configuration, the quality of the inner surface of the tire is further improved.

  In the present specification, “rim” is an industrial standard effective for a region where tires are produced and used, and in Japan, JATMA (Japan Automobile Tire Association) JATMA YEAR BOOK, in Europe ETRTO (The European Tire STANDARDS MANUAL in STANDARDS AND RIM TECHNICAL ORGANIZATION), YEAR BOOK etc. in TRA (The Tire and Rim Association, Inc.) in the US, or standard rims in application sizes described in the future (STANDARDS MANUAL in ETRTO) Measurement Rim refers to Design Rim) in YEAR BOOK of TRA. (That is, the above-mentioned "rim" includes the size that can be included in the above-mentioned industry standard in addition to the current size. An example of "the size described in the future" is ETRTO STANDARDS MANUAL 2013) In the version, mention may be made of the sizes described as “FUTURE DEVELOPMENTS”), but in the case of a size not described in the above-mentioned industry standard, a rim of a width corresponding to the bead width of the tire. Also, the “specified internal pressure” refers to the air pressure (maximum air pressure) corresponding to the tire maximum load capacity of the standards such as the above-mentioned JATMA in the applicable size tire. In addition, in the case of the size which is not described in the said industrial standard, "prescribed internal pressure" shall mean the air pressure (maximum air pressure) corresponding to the maximum load capability specified for every vehicle equipped with a tire.

In the pneumatic tire according to the present invention, the pneumatic tire has a bead portion,
It is preferable that five or more of the bladder ridges are formed per inch in the tire circumferential direction at any position in the tire width direction on the inner surface of the bead portion.
According to this configuration, the quality of the inner surface of the tire is further improved.

  According to the present invention, it is possible to provide a tire vulcanizing bladder having improved durability, and to improve the quality of the tire inner surface of a pneumatic tire manufactured using the tire vulcanizing bladder.

It is a width direction sectional view showing a tire vulcanization bladder concerning one embodiment of the present invention. FIG. 1 is a developed view showing a part of an outer surface of a tire vulcanizing bladder according to an embodiment of the present invention. It is sectional drawing which shows a groove part. It is a tire width direction sectional view showing a pneumatic tire concerning one embodiment of the present invention. It is an expanded view which shows a part of tire inner surface of the pneumatic tire concerning one Embodiment of this invention. It is sectional drawing which shows a bladder bridge.

  Hereinafter, embodiments of the present invention will be illustrated and described in detail with reference to the drawings. Incidentally, dimensions and the like in the present specification are as in the case of a new product unless otherwise noted.

Tire bladders for vulcanizing tires
FIG. 1 is a widthwise sectional view showing a tire vulcanizing bladder 1 according to an embodiment of the present invention. FIG. 1 shows a schematic cross-sectional shape of a tire vulcanizing bladder 1 in a state of being pressed against the inner surface of an unvulcanized tire. As shown in FIG. 1, the tire vulcanizing bladder 1 (hereinafter simply referred to as a bladder) is a rubber bag made of a tubular ring having a circular or horseshoe-shaped cross section (in the illustrated example, a horseshoe shape). . The bladder 1 of the present embodiment is made of fluororubber (the rubber composition is mainly composed of fluororubber).

  FIG. 2 is a developed view showing a part of the outer surface of the tire vulcanizing bladder 1 according to one embodiment of the present invention. As shown in FIG. 2, on the circumference of the outer surface of the bladder 1, a plurality of groove portions 2 extending in the width direction are formed. In addition, although the groove part 2 is arrange | positioned at equal intervals in the circumferential direction in this example, you may arrange | position a space | interval. Further, in this example, the groove 2 extends obliquely in the width direction, but may extend in the width direction. Furthermore, in this example, the groove 2 extends linearly in this developed view, but may extend in a curved manner. Also, in this example, the grooves 2 extend continuously, but may extend discontinuously.

Here, in the bladder 1 of the present embodiment, in a state where the groove portion 2 is pressed against the inner surface of the unvulcanized tire, five or more groove portions 2 are formed per inch in the circumferential direction at any position in the width direction on the outer surface. ing. Further, as shown in FIG. 2, in the present embodiment, a plurality of concave portions 3 connecting between the groove portions 2 are formed between the groove portions 2 (not shown in FIG. 3). In the present embodiment, the depth of the recess 3 is 0.1 to 0.25 mm. The recessed part 3 is a random shape which has a part which branched three or more as shown in figure, and has what is called a pebble pattern.
Hereinafter, the operation and effect of the tire vulcanizing bladder 1 of the present embodiment will be described.

In the tire curing step, it was found that stress is generated in the groove portion 2 and a crack may be generated and developed.
According to the tire vulcanizing bladder 1 of the present embodiment, five or more grooves 2 are formed per inch in the circumferential direction at any position in the width direction on the outer surface. The stress can be relieved, and the generation and propagation of the crack can be suppressed.
According to the tire vulcanizing bladder 1 of the present embodiment, the durability can be improved, and the quality of the tire inner surface of the pneumatic tire manufactured using the tire vulcanizing bladder can be improved.

Here, in the tire vulcanizing bladder 1 of the present invention, it is preferable that the groove portion 2 be formed at 20 or less per 1 inch in the circumferential direction at any position in the width direction on the outer surface. This is because defects in the rubber flow in the vulcanization step can be suppressed.
Further, in the tire vulcanizing bladder 1 of the present invention, it is preferable that the groove portions 2 be formed at 8 or more and 15 or less per 1 inch in the circumferential direction at any position in the width direction on the outer surface. By forming the groove portions 2 eight or more per 1 inch in the circumferential direction, it is possible to further alleviate the concentration of stress per groove portion 2 while, on the other hand, the groove portions 2 are formed 15 times per 1 inch in the circumferential direction It is because the defect of the rubber flow in a vulcanization process can be controlled further by forming below. In the tire vulcanizing bladder 1 of the present invention, it is preferable that ten or more groove portions 2 are formed per inch in the circumferential direction at any position in the width direction on the outer surface. By forming 10 or more grooves 2 per inch in the circumferential direction, it is possible to further alleviate the concentration of stress per groove 2.

FIG. 3 is a cross-sectional view showing the groove 2.
In the present invention, assuming that the gauge of the tire vulcanization bladder 1 is A (mm) and the depth of the groove 2 is B (mm), the ratio B / A is
0.03 ≦ B / A ≦ 0.15
It is preferable to satisfy
By setting the ratio B / A to 0.03 or more, it is possible to suppress the decrease in the life of the bladder 1 due to wear, and on the other hand, by setting the ratio B / A to 0.15 or less, the groove 2 The rigidity with respect to the stress which arises can be ensured, and the durability of the bladder 1 can further be improved.

In the present invention, assuming that the width of the groove 2 is C (mm) and the depth of the groove 2 is B (mm), the ratio B / C is
0.3 ≦ B / C ≦ 1.0
It is preferable to satisfy
By setting the ratio B / C to 0.3 or more, it is possible to suppress a decrease in the life of the bladder 1 due to wear, and on the other hand, by setting the ratio B / C to 1.0 or less, the groove 2 The rigidity with respect to the stress which arises can be ensured, and the durability of the bladder 1 can further be improved.

In the present invention, assuming that the number of grooves 2 in the entire circumference is D (pieces) and the depth of the grooves 2 is B (mm), the ratio B / D is
0.001 ≦ B / D ≦ 0.006
It is preferable to satisfy
By setting the ratio B / D to 0.001 or more, it is possible to suppress the decrease in the life of the bladder 1 due to wear, and on the other hand, by setting the ratio B / D to 0.006 or less, the groove 2 The rigidity with respect to the stress which arises can be ensured, and the durability of the bladder 1 can further be improved.

In the present invention, when the curvature radius of the corner of the bottom of the groove 2 is E (mm) and the depth of the groove 2 is B (mm) in the cross section in the extension direction of the groove 2, the ratio B / E is ,
1.0 ≦ B / E ≦ 5.0
It is preferable to satisfy
By setting the ratio B / E to 1.0 or more, it is possible to suppress the decrease in the life of the bladder 1 due to wear, and on the other hand, by setting the ratio B / E to 5.0 or less, the groove 2 The rigidity with respect to the stress which arises can be ensured, and the durability of the bladder 1 can further be improved.

  In the present invention, the depth B of the groove 2 is preferably 0.3 to 0.5 mm.

In the present invention, it is preferable that a plurality of concave portions 3 connecting between the groove portions 2 be formed between the groove portions 2. This is because the stress generated in the groove portion 2 can be further relieved, and the durability of the bladder 1 can be further improved.
In addition, it is preferable that the recessed part 3 is provided only in the part contact | abutted on the inner surface of the part corresponding to a bead part from the hump part of the tire which becomes a finished product among the bladders 1. The stress can be further relieved at the place where the stress is most likely to be concentrated, and a defect in the rubber flow can be suppressed, and the air can also be discharged through the recess 3. On the other hand, in the center portion of the tire, which is a region in the tire width direction between hump portions, tire inner surface members such as noise suppressing members such as sponge materials and puncture preventing members such as sealant can be easily attached. When the convex portion 18 is formed in the center portion, the contact area between the tire inner surface member 19 and the tire inner surface 16 is reduced, and the adhesive force is reduced.
In the present invention, the groove 2 may be configured not to have the recess 3 connecting the groove 2.
In the tire vulcanizing bladder according to the present invention, the recess 3 is at least in contact with the joint on the carcass ply of the green tire (portion where the carcass ply overlaps) of the circumference of the outer surface of the bladder 1. It is preferable to provide in the contact position and its vicinity. At this position, the air is most likely to remain on the circumference, so it is possible to efficiently suppress the remaining of the air and to suppress the generation of the bear in the tire after vulcanization. For example, the recess 3 may be provided all around the outer surface of the bladder 1.
As described above, since the concave portions 3 themselves are arranged in a random shape, the shape of the small land section partitioned there is also random. On the other hand, it is preferable that the number density of the small land portions be substantially constant on the entire circumference of the outer surface of the bladder 1. Alternatively, on the circumference of the outer surface of the bladder 1, at least a position where the green tire abuts on the joint on the carcass ply of the carcass ply (portion where the carcass ply overlaps) and the number density in the vicinity thereof. It is preferable to increase from the other places of

<Pneumatic tire>
FIG. 4 is a cross-sectional view in the tire width direction showing the pneumatic tire 10 according to an embodiment of the present invention. As shown in FIG. 4, the tire 10 has a belt layer of one or more layers (two layers in the illustrated example) on the outer side in the tire radial direction of the carcass 12 straddling the bead cores 11 a embedded in the pair of bead portions 11 in a toroidal shape. And a belt protection layer 14 having one or more layers (one layer in the illustrated example), and a tread 15 in this order. Moreover, the bead filler 11b of the cross-sectional triangle shape is arrange | positioned on the tire radial direction outer side of the bead core 11a. The tire of the present invention is not particularly limited as to the structure other than the tire inner surface 16. For example, it may be configured not to have the bead filler 11 b and the belt protection layer 14. Further, the carcass structure and the belt structure are not particularly limited, such as the number of carcass plies, the number of layers of the belt layer and the belt protective layer, and the material of the cord.

The pneumatic tire of the present embodiment is manufactured through a vulcanization process using the tire vulcanization bladder of the above-described embodiment. Therefore, the tire of the present embodiment has one or more particles containing fluorine having a maximum diameter of 1.0 μm or more per 100 μm ² area of the tire inner surface 16.

  FIG. 5 is a developed view showing a part of the tire inner surface 16 of the pneumatic tire according to an embodiment of the present invention. As shown in FIG. 5, in the tire according to the present embodiment, a plurality of bladder ridges 17 extending in the tire width direction are formed on the circumference of the tire inner surface 16. In addition, although the groove part 2 is arrange | positioned at equal intervals in the tire circumferential direction in this example, you may arrange | position a space | interval. Also, in this example, the bladder ridge 17 extends obliquely in the tire width direction, but may extend along the tire width direction. Furthermore, in this example, the bladder ridge 17 extends rectilinearly in this unfolded view, but may extend curvilinearly. Also, in this example, the bladder ridges 17 extend continuously but may extend discontinuously.

Five or more bladder ridges 17 are formed per inch of tire circumferential direction at any position in the tire width direction of the tire inner surface 16. Further, as shown in FIG. 5, a plurality of convex portions 18 connecting the bladder ridges 17 are formed between the bladder ridges 17 (not shown in FIG. 6). The convex portion 18 is formed only on the inner surface of the shoulder portion, and is not formed on the center portion which is a region between the shoulder portions. In the present embodiment, the height of the convex portion 18 is 0.1 to 0.25 mm under atmospheric pressure. The convex portion 18 has a random shape having three or more branched portions as shown, and has a so-called pebble pattern. In addition, at least one of the bladder ridges 17 is formed per inch in the tire circumferential direction at any position in the tire width direction on the inner surface of the bead portion 11.
Hereinafter, the operation and effect of the pneumatic tire of the present embodiment will be described.

In the tire curing step, it was found that stress is generated in the groove portion 2 of the bladder 1 and a crack may occur or develop.
According to the pneumatic tire 10 of the present embodiment, at least five of the bladder ridges 17 are formed per inch of the tire circumferential direction at any position in the tire width direction of the tire inner surface 16. The stress per groove portion 2 of the bladder 1 can be relieved, and the generation and propagation of the crack can be suppressed. Therefore, the quality of the tire inner surface 16 of the pneumatic tire 10 is excellent.

Here, in the pneumatic tire 10 of the present invention, it is preferable that 20 or less of the bladder ridges 17 are formed per inch of the tire circumferential direction at any position in the tire width direction of the tire inner surface 16. It is because it becomes a high quality tire in which the defect of the rubber flow in the vulcanization process is suppressed.
Further, in the pneumatic tire 10 of the present invention, it is preferable that 8 or more and 15 or less of the bladder ridges 17 per inch in the tire circumferential direction be formed at any position in the tire width direction of the tire inner surface 16. By forming at least eight bladder ridges 17 per inch in the circumferential direction, the quality of the tire inner surface 16 can be further improved, while at the same time, fifteen or less bladder ridges 17 are formed in one circumferential direction. This is because defects in the rubber flow in the vulcanization step can be further suppressed. In the pneumatic tire 10 of the present invention, it is preferable that 10 or more bladder ridges 17 are formed in one circumferential direction. This is because the quality of the tire inner surface 16 can be further improved by forming 10 or more bladder ridges 17 per inch in the circumferential direction.

FIG. 6 is a cross-sectional view showing the bladder ridge 17.
In the present invention, when the width of the bladder ridge 17 is C ′ (mm) and the height of the bladder ridge 17 is B ′ (mm), the ratio B ′ / C ′ is
0.3 ≦ B ′ / C ′ ≦ 1.0
It is preferable to satisfy
By setting the ratio B '/ C' to 0.3 or more, the life of the bladder 1 to be used can be prevented from decreasing due to wear, while the ratio B '/ C' is set to 1.0 or less By this, the quality of the tire inner surface 16 can be further improved.

In the present invention, assuming that the number of bladder ridges 17 in the entire circumference is D ′ (book) and the height of the bladder ridge 17 is B ′ (mm), the ratio B ′ / D ′ is
0.001 ≦ B ′ / D ′ ≦ 0.006
It is preferable to satisfy
By setting the ratio B '/ D' to 0.001 or more, the life of the bladder 1 to be used can be prevented from decreasing due to wear, while the ratio B '/ D' is set to 0.006 or less This is because the quality of the tire inner surface 16 can be further improved.

In the present invention, when the radius of curvature of the corner of the top of the bladder ridge 17 is E ′ (mm) and the height of the bladder ridge 17 is B ′ (mm) in the cross section in the extension direction of the bladder ridge 17, the ratio B ′ / E 'is
1.0 ≦ B ′ / E ′ ≦ 5.0
It is preferable to satisfy
By setting the ratio B '/ E' to 1.0 or more, the life of the bladder 1 used can be prevented from decreasing due to abrasion, while the ratio B '/ E' is set to 5.0 or less This is because the quality of the tire inner surface 16 can be further improved.

  In the present invention, the height B ′ of the bladder ridge 17 is preferably, for example, 0.3 to 0.5 mm for a passenger car tire.

In the present invention, it is preferable that a plurality of convex portions 18 connecting the bladder ridges 17 be formed between the bladder ridges 17, and the convex portions 18 be formed only on the inner surface of the hump portion and the inner surface of the bead portion.
The stress can be further relieved in the portion corresponding to the hump portion to the bead portion where the stress is most likely to be concentrated, and the defect of the rubber flow can be suppressed, and the quality of the tire is excellent. The air can also be discharged through the recess 3 (transferred as the protrusion 18). On the other hand, in the center portion which is a tire width direction area between humps of the tire 10, the tire inner surface member such as a noise suppressing body such as a sponge material or a puncture preventing member such as a sealant can be easily attached. When the convex portion 18 is formed in the center portion, the contact area between the tire inner surface member 19 and the tire inner surface 16 is reduced, and the adhesive force is reduced.
In the present invention, the convex portions 18 connecting the bladder ridges 17 may not be provided between the bladder ridges 17, and the positions of the convex portions 18 are not necessarily limited to the case of forming only the shoulder portions.

In the present invention, on the inner surface of the bead portion 11, it is preferable that five or more bladder ridges 17 are formed per inch of the tire circumferential direction on the circumference. This is because the quality of the tire inner surface 16 can be further improved.
In the pneumatic tire according to the present invention, it is preferable that the convex portion 18 be provided at least at the position of the bonding portion on the periphery of the carcass ply on the periphery of the tire inner surface 16 and in the vicinity thereof. It is because a bear can be reduced efficiently as mentioned above. For example, the convex portion 18 can be provided over the entire circumference of the tire inner surface 16.
As described above, since the convex portions 3 themselves are arranged in a random shape, the shape of the small concave portions partitioned thereto is also random. On the other hand, it is preferable that the number density of the small recesses be substantially constant on the entire circumference of the tire inner surface 16. Alternatively, it is preferable to increase the number density more than at other locations on the periphery at least at the position of the joint on the periphery of the carcass ply and on the periphery of the inner surface 16 of the tire.

In the present invention, the tire inner surface member 19 can be disposed at any position in the tire width direction of the tire inner surface 16. For example, in the case of arranging on the inner surface of the center portion, the tire inner surface member 19 can be arranged in the area of a part or the whole of the center portion.
Further, in the present invention, the tire inner surface member 19 can be disposed in at least a partial region on the circumference of the tire inner surface 16. The tire inner surface member 19 is preferably disposed on the entire circumference of the tire inner surface 16.
In the present embodiment, the tire inner surface member 19 is a noise suppressing body made of a sponge material. The sponge material is a sponge-like porous structure, and includes, for example, a so-called sponge having open cells in which rubber or synthetic resin is foamed. In addition to the above-mentioned sponge, the sponge material includes web-like materials in which animal fibers, plant fibers or synthetic fibers are entangled and integrally connected. In addition, the above-mentioned "porous structure" is the meaning including not only the structure which has an open cell but the structure which has a closed cell. The sponge material as described above converts the vibrational energy of the air whose air gap is formed on the surface or inside into the thermal energy. This suppresses cavity resonance in the tire lumen, and as a result, road noise can be reduced. In addition, the sponge material is easy to be deformed such as contraction and bending. Therefore, even if the noise suppressing body formed of the sponge material is fixed to the tire inner surface 16, the deformation of the tire 10 during traveling is not substantially affected. That is, even when the noise suppressing body is fixed to the tire inner surface 16, the steering stability and the like are hardly adversely affected. Examples of the material of the sponge material include synthetic polyurethane resin sponges such as ether polyurethane foam, ester polyurethane foam, polyethylene sponge, chloroprene rubber sponge (CR sponge), ethylene propylene rubber sponge (EPDM sponge), nitrile rubber sponge (NBR sponge) And rubber sponges. It is preferable to use a polyurethane-based or polyethylene-based sponge including an ether-based polyurethane sponge, in view of noise suppression properties, lightness, foam adjustability, durability, and the like. The material constituting the noise suppressing body may be any material that can be controlled to reduce cavity resonance energy by relaxation of cavity resonance energy, absorption, conversion to another energy (for example, thermal energy), etc. The material is not limited to the above-described sponge material, and, for example, urethane or non-woven fabric can also be used. In addition, the specific gravity of the sponge material is preferably set to 0.005 to 0.06, preferably 0.01 to 0.04, in consideration of the balance between the increase in tire weight and the effect of suppressing cavity resonance. Is more preferable, and it is particularly preferable to set it to 0.01 to 0.03. Furthermore, the volume of the noise suppressing body is preferably 0.4% to 20% of the total volume of the tire lumen. By securing the volume of the noise suppressing member at 0.4% or more with respect to the entire volume of the tire lumen, it is easy to realize the reduction effect of the desired amount (for example, 2 dB or more) of the cavity resonance energy. The noise suppressing member is more preferably 1% or more, more preferably 2% or more, and particularly preferably 4% or more of the total volume of the tire lumen. On the other hand, even if the volume of the noise suppressing body is configured to exceed 20% of the entire volume of the tire lumen, improvement in the reduction effect of the cavity resonance energy can not be expected. Rather, the weight balance of the assembly may be degraded. From such a point of view, the volume of the noise suppressing member is more preferably 16% or less, and particularly preferably 10% or less of the entire volume of the tire lumen. The above-mentioned volume ratio is not related to the number of noise suppressing members. That is, in the case where there are a plurality of noise suppressing members, similar effects can be obtained as long as the sum of the volumes of all of the plurality of noise suppressing members satisfies the above-described volume ratio relationship.
Furthermore, in the present embodiment, the tire inner surface member 19 is a noise suppressing body, but may be various members such as a puncture preventing member such as a sealant. If a sealant is used, it can be any known material.
For example, when the tire inner surface member 19 is a noise suppressing body, the noise reduction properties of the tire can be improved, and when the noise reduction body is a sponge material, the noise reduction properties of the tire can be effectively improved. Can. Further, for example, when the tire inner surface member 19 is used as a puncture prevention member, it is possible to prevent a tire from being punctured, and when the puncture prevention member is used as a sealant, it is possible to effectively prevent a tire from being punctured. it can.

As mentioned above, although embodiment of this invention was described, this invention is not limited at all to said embodiment. In particular, the concave portion 3 and the convex portion 18 may have any pebble pattern as long as they connect the grooves 2 or connect the bladder ridges 17, and the shape, width, number, etc. are particularly limited. I will not. Also, for example, in the above embodiment, the concave portions 3 and the convex portions 18 have random shapes and arrangement, but some or all of them may have regularity and shapes. Further, the concave portions 3 and the convex portions 18 can be in communication with each other, and the number of the communication (branch) is not particularly limited.
EXAMPLES Hereinafter, examples of the present invention will be described, but the present invention is not limited to the following examples.

In order to confirm the effects of the present invention, tire vulcanizing bladders made of fluoro rubber according to Inventive Examples 1 to 4 and Comparative Example were made on a trial basis. Table 1 shows the specifications of each bladder and the specifications of a tire manufactured using the bladder.
About the invention examples 1-4 of the said, and a comparative example, the test which evaluates durability of a bladder and the quality of a tire inner surface was done.

<Bladder Durability>
After vulcanizing the tire using each bladder, the presence or absence of a crack in the groove portion was confirmed, and the durability of the bladder was evaluated by the number of times of use until the crack occurs. An evaluation result is shown by the index display which made the comparative example 100, and it shows that it is excellent in durability, so that a numerical value is large.
<Quality of tire inner surface>
The cracks of each bladder were transferred to the inner surface of the tire manufactured using each bladder, and the presence or absence of a recess generated in the vicinity of the bladder ridge was confirmed, and the quality was evaluated by the number of recesses on the tire inner surface. The evaluation result is indicated by an index of Comparative Example 100. The larger the value, the better the quality of the inner surface of the tire.
Each evaluation result is shown in Table 1.

  As shown in Table 1, it can be seen that invention examples 1 to 4 are superior to the comparative example in the durability of the bladder and the quality of the inner surface of the tire.

1: Tire vulcanizing bladder, 2: Groove, 3: Recess,
10: pneumatic tire, 11: bead portion, 11a: bead core,
11b: bead filler, 12: carcass, 13: belt, 14: belt protective layer,
15: tread, 16: tire inner surface, 17: bladder ridge, 18: convex portion

Claims (12)

A tire vulcanizing bladder made of fluorine rubber,
A plurality of grooves extending in the width direction are formed on the circumference of the outer surface of the tire curing bladder,
In a state where the groove portion is pressed against the inner surface of an unvulcanized tire, at least five grooves are formed per inch in the circumferential direction at any position in the width direction on the outer surface. For the bladder. Assuming that the gauge of the tire vulcanization bladder is A (mm) and the depth of the groove is B (mm), the ratio B / A is
0.03 ≦ B / A ≦ 0.15
The tire vulcanizing bladder according to claim 1, wherein Assuming that the width of the groove is C (mm) and the depth of the groove is B (mm), the ratio B / C is
0.3 ≦ B / C ≦ 1.0
The tire vulcanizing bladder according to claim 1 or 2, wherein Assuming that the number of grooves in the entire circumference is D (pieces) and the depth of the grooves is B (mm), the ratio B / D is
0.001 ≦ B / D ≦ 0.006
The tire vulcanizing bladder according to any one of claims 1 to 3, wherein When the radius of curvature of the corner of the bottom of the groove is E (mm) and the depth of the groove is B (mm) in the cross section in the extension direction of the groove, the ratio B / E is
1.0 ≦ B / E ≦ 5.0
The tire vulcanizing bladder according to any one of claims 1 to 4, wherein   The tire vulcanizing bladder according to any one of claims 1 to 5, wherein a plurality of concave portions connecting between the groove portions are formed between the groove portions. A pneumatic tire comprising one or more particles containing fluorine having a maximum diameter of 1.0 μm or more per 100 μm ² of the inner surface of the tire,
A plurality of bladder ridges extending in the tire width direction are formed on the circumference of the inner surface of the tire,
The pneumatic tire is characterized in that five or more bladder ridges are formed per inch in the tire circumferential direction at any position in the tire width direction on the inner surface of the tire. Assuming that the width of the bladder bridge is C ′ (mm) and the height of the bladder bridge is B ′ (mm), the ratio B ′ / C ′ is
0.3 ≦ B ′ / C ′ ≦ 1.0
The pneumatic tire according to claim 7, wherein Assuming that the number of the bladder bridges in the entire circumference is D ′ (book) and the height of the bladder bridges is B ′ (mm), the ratio B ′ / D ′ is
0.001 ≦ B ′ / D ′ ≦ 0.006
The pneumatic tire according to claim 7 or 8, wherein When the radius of curvature of the corner of the top of the bladder ridge in the extension direction of the bladder ridge is E ′ (mm) and the height of the bladder bridge is B ′ (mm), the ratio B ′ / E ′ is ,
1.0 ≦ B ′ / E ′ ≦ 5.0
The pneumatic tire according to any one of claims 7 to 9, wherein   A plurality of convex portions connecting the bladder ridges are formed between the bladder ridges, and the convex portions attach the tire to the rim, fill the prescribed internal pressure, and are unloaded from the tread surface from the tread surface. The pneumatic tire according to any one of claims 7 to 10, wherein the tire is formed only from the inner surface of the hump portion which is the region with the smallest radius of curvature in the tire outer contour up to the large position to the inner surface of the bead portion. . The pneumatic tire has a bead portion,
The pneumatic tire according to any one of claims 7 to 11, wherein five or more of said bladder ridges are formed per inch of tire circumferential direction at any position in the tire width direction on the inner surface of said bead portion. .

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