Patent Application
20200316903
Certain embodiments pertain to a coated garnet particle product configured for being incorporated into tire treads. In particular certain embodiments pertain to a coated garnet particle product configured for increasing wear and gripping capabilities of tire treads on dry, wet, icy, or snowy road conditions when incorporated into the tire treads.
Many tires are not suitable for driving conditions involving snowy or icy conditions. Attempts to provide for greater tire traction in snowy or icy conditions have taken different approaches. In a first approach, add-on tire traction devices have been developed which can be attached to a tire when needed for snowy or icy conditions. These add-on tire traction devices include, for example, tire chains, tire cables, and the like. While these do provide tire traction in some snowy or icy conditions, they have a number of disadvantages. They must be carried in the vehicle, thereby taking up space in the vehicle, when it is not snowy or icy so that they can be ready to be deployed if snowy or icy conditions are confronted. Also, they must often be purchased for specific tire sizes. If a consumer makes an error in buying the correct size, the purchased tire traction devices could be useless if they cannot be installed on the tire when needed. And, there is often a certain level of knowledge and skill to placing these on a tire when needed.
Another approach has been to incorporate traction-providing fillers into tire treads. Some of these fillers for example have been walnut shells, wire, fiberglass, aluminum oxide, and the like. Such tires however have not been found to be satisfactory in having the combined required features of long wear, economy of manufacture, and good road traction.
Tires have also been provided with metal or rubber studs but these traction devices are noisy, are illegal in some states, and where legal can only be used in winter months. Moreover, while studded tires provide traction in some snowy and icy condition, they provide less satisfactory traction in rainy or dry pavement conditions. In addition, studded tire are known to wear out road surfaces, especially when driven on pavement during rainy or dry pavement conditions.
Applicant now discusses U.S. Pat. No. 4,082,131 “Tire Tread Structure” by James I. Scheller (the “Scheller I”). Scheller I describes a tire tread structure that included garnet particles. This tire tread structure was described as combining features of long wear, of being reasonably economical to manufacture, of having good road traction, and generally of being legal in all states the year around. The described tire tread was formed by the intermixing of garnet particles with a rubber compound which was then used to make tire tread so that the tire has improved traction with the road surface and at the same time has long wearing qualities and other features mentioned. The described particle size was said to vary but it was said that the amount of garnet used be used should be at least 10% by weight of the rubber in the tread.
While the tire tread structure described in Scheller I has advantages, it also has disadvantages. In particular when a tire tread with the garnet particles of Scheller I are used on a road, and the garnet particles are in contact with a road surface, the friction with the road surface (or with snow or ice) causes some of the garnet particles to prematurely come lose from the tire tread. This premature loss of these garnet particles from the tire tread reduces some of the benefits of this tire tread. For example, there is decreased traction and decreased wear. Thus, there is a need for a solution to reduce the above premature loss of garnet particles while providing a tire that provides good wear and traction in all seasons.
This summary is provided as a convenience to the reader as a summary of one or more embodiments. The discussion in this Summary is intentionally simplified. It is not intended as a guide for construing or limiting the scope of the claims.
Some embodiments include a coated garnet particle product that includes at least a plurality of garnet particles and at least one coating that individually coats the garnet particles of the plurality of garnet particles, the at least one coating including at least a bonding agent. In these embodiments the plurality of garnet particles and the at least one coating defines a plurality of coated garnet particles. The plurality of coated garnet particles may be suitable for mixing with one or more tire rubber formulations for incorporation into one or more tire treads of one or more tires with at least some of the plurality of coated garnet particles partially protruding from the one or more tire treads for engaging one or more road surfaces when the one or more tires are in use on the one or more road surfaces thereby increasing wear and gripping capabilities of the one or more tires on dry, wet, icy, or snowy road conditions. In some embodiments, the bonding agent is a bonding agent for elastomers that is configured to adhere to said tire rubber formulations after said mixing and subsequent heating and pressurization as part of a tire vulcanization process. Thus, after the tire vulcanization process, the incorporation of the plurality of coated garnet particles into the one or more tire treads of the one or more tires, and upon the use of the one or more tires on the one or more road surfaces, the plurality of coated garnet particles adhere more strongly to said one or more tire threads than would uncoated garnet particles. Loss of some of the plurality of coated garnet particles from road friction is thus reduced relative to a loss of uncoated garnet particles from road friction and the wear and gripping capabilities of the one or more tires on the one or more road surfaces is thereby increased relative to wear and gripping capabilities of tires with uncoated garnet particles.
Some embodiments include a garnet tire that provides secure gripping on a variety of road conditions, including on icy, snowy, wet, and dry road conditions. In some embodiments, the garnet tire includes at least a tire tread and a plurality of coated garnet particles embedded throughout the tire tread of said garnet tire with at least some of the plurality of coated garnet particles partially protruding from a tire tread surface of said tire tread for gripping one or more road surfaces when the garnet tire is mounted to a moving motor vehicle for operation on the one or more road surfaces. In these embodiments, the plurality of coated garnet particles includes at least one coating that individually coats the garnet particles of the plurality of garnet particles and that includes at least a bonding agent configured to adhere to elastomers under heat and pressure of a vulcanization process. In some embodiments, because of the at least one coating the coated garnet particles adhere more strongly to the tire tread of the tire relative to uncoated garnet particles. Thus, loss of coated garnet particles from road friction is reduced relative to a tire having uncoated garnet particles. And the coated garnet particles configure the tire for an increased gripping capability on road surfaces relative to a gripping capability of a tire with uncoated garnet particles.
In some embodiments, a method of manufacturing a coated garnet particle product, includes at least rinsing a plurality of garnet particles and applying a forced air stream to the plurality of garnet particles to create a static charge on the plurality of garnet particles. In some embodiments the method of manufacturing further includes mixing the plurality of garnet particles with at least a silane primer and allowing to dry, the plurality of garnet particles being mixed with a silane primer that is an oil-derived or synthetic polymer that is configured to further clean the plurality of garnet particles and prepare the plurality of garnet particles for application of a bonding agent. In some embodiments, the method further includes mixing the plurality of garnet particles with at least a bonding agent that is a bonding agent for elastomers that includes at least a polymer-adhesive organic solvent and allowing to dry.
Various embodiments will now be described, by way of example, with reference to the accompanying drawings. It should be noted that these drawings are not necessarily to scale. In particular, for purposes of illustration, the garnet particles depicted are enlarged relative to their actual size in various embodiments. Regarding the size of garnet particles in various embodiments, the reader should rely not on the sizes of garnet particles as depicted in these figures, but should instead rely on the discussion of their size in the Detailed Description that follows. The figures are:
Some embodiments are now described with reference to the above-described figures. In the following description, reference is often made to “some embodiments.” These references to “some embodiments” are not necessarily referring to the same embodiments, as numerous and varied embodiments are possible. In addition, the drawings are simplified drawings which omit various details to focus on what is described in this detailed description. The omission of various details is not intended to imply that these various details would not be present in an actual physical embodiment. Instead, omissions of various details are merely to avoid clutter in the presentation and to aid ease of explanation and understanding. Further, these simplified drawings are intended to illustrate the principles of various described embodiments and are not necessarily drawn to scale. In addition, as noted above, for purposes of illustration, the garnet particles depicted are enlarged relative to their actual size in various embodiments. Regarding the size of garnet particles in various embodiments, the reader should rely not on the sizes of garnet particles as depicted in these figures, but should instead rely on the discussion of their size in the discussion below.
Preliminarily, various embodiments described herein related to coated garnet particles (i.e., coated garnet particle product) which may be incorporated into the tire tread of tires. Referencing
The garnet tire 200 of
Turning to
Turning now to
In the discussion below, there is discussion of coated garnet particles. As is well-known, garnet is a semi-precious stone. On the MOHs Hardness scale, garnet ranges from about 6.5 to 7.5. And garnet typically has a specific gravity of about 3.5 to 4.3. Although any grade of garnet could be used, the garnet typically used in embodiments discussed herein is industrial grade garnet particles. In some embodiments, these garnet particles could be industrial grade garnet crystals. Also, while garnet particles having a high degree of purity could be used, the industrial grade garnet which is suitable for some embodiments does not require a high degree of purity. Enough purity to retain garnet's hardness as discussed above.
In the discussion below, there is discussion of tire rubber formulations. Many different types of tire formulations are known in the art. Some tire rubber formulations use natural rubber. Some use synthetic rubber. Some use additional chemicals, additives, or materials. Some tire rubber formulations are proprietary. Some are trade secrets of their respective manufacturer. For purposes of the various embodiments below, there is no intent to limit embodiments to any particular tire rubber formulations. Instead one having ordinary skill in the art when informed by the principles disclosed herein would be able to select from known tire rubber formulations without undue experimentation.
In the discussion below, there is discussion of garnet tires, consistent with some embodiments. Garnet tires, as described herein, can be any known type of tire, including without limitation radial tires, truck tires, SUV tires, all-season tires, all-terrain tires, passenger vehicle tires, snow tires, new tires, retread tires, and the like.
In addition, no particular method of tire manufacturing is required to practice embodiments of this invention. A method of manufacturing a coated garnet particle product is described and claimed below. Once the coated garnet particle product has been manufactured, it can be mixed with a tire rubber formulation (e.g., in a cement mixer or other type of industrial mixer). After that, there is no restriction on the type of manufacturing process that can be used. It should be noted that the coated garnet particles have a bonding agent that will bond to the tire rubber formulation during a heating process, such as a vulcanization process. Therefore, some form of heating is anticipated as part of the tire manufacturing process. For purposes of the various embodiments below, the type of tire manufacturing process used, after the coated garnet particles are mixed with the tire rubber formulation is immaterial—as long as some type of heating process similar to vulcanization is included. Since vulcanization is a standard part of tire manufacture, it is anticipated that any known tire manufacturing process would be suitable for having coated garnet particles incorporated into the tread thereof. For purposes of the various embodiments below, there is no intent to limit embodiments to any particular tire manufacturing processes. Instead one having ordinary skill in the art when informed by the principles disclosed herein would be able to select from known tire manufacturing processes without undue experimentation.
Referencing
The plurality of coated garnet particles 204a, 204b are suitable for mixing with one or more tire rubber formulations (not shown) for incorporation into one or more tire treads 202 of one or more tires 200 with at least some of the plurality of coated garnet particles 204a, 204b partially protruding from the one or more tire treads for engaging one or more road surfaces (not shown) when the one or more tires 200 are in use on the one or more road surfaces thereby increasing wear and gripping capabilities of the one or more tires on dry, wet, icy, or snowy road conditions. In addition, the bonding agent (of the at least one coating 208) is a bonding agent for elastomers that is configured to adhere to said tire rubber formulations after said mixing and subsequent heating and pressurization as part of a tire vulcanization process.
Thus, after the tire vulcanization process, the incorporation of the plurality of coated garnet particles into the one or more tire treads of the one or more tires, and upon the use of the one or more tires on the one or more road surfaces, the plurality of coated garnet particles 204a, 204b adhere more strongly to said one or more tire threads (e.g., tire tread 202) than would uncoated garnet particles and thereby loss of some of the plurality of coated garnet particles 204a, 204b from road friction is reduced relative to a loss of uncoated garnet particles from road friction, and the wear and gripping capabilities of the one or more tires on the one or more road surfaces is thereby increased relative to wear and gripping capabilities of tires with uncoated garnet particles.
In some embodiments, the plurality of coated garnet particles 204a, 204b are configured to be mixed into tire rubber formulations at a ratio of between 5 and 15 percent by weight of tread rubber formulation. That is, the benefits described herein are achieved by a mixing of the plurality of coated garnet particles 204a, 204b with the tire rubber formulations at a ratio between 5 and 15 percent by weight of tread rubber formulation.
In some embodiments, at least some individual coated garnet particles 204a, 204b of the plurality of coated garnet particles 204a, 204b range in size between 8-200 mesh sizing. Mesh sizing is a standard measure well known to those of skill in the art. It describes a number of openings in a one-inch screen. Mesh sizing can be converted to inches, microns, and millimeters. For example, a mesh size of eight converts to a particle 0.937 inches in diameter, 2380 microns in diameter, or 2.380 millimeters in diameter. A mesh size of 200 converts to a particle diameter of 0.0029 inches, 74 microns, or 0.74 millimeters. The above conversions are taken from “MESH/INCH/MILLIMETER—CONVERSION CHART (U.S. STANDARD)” published by YAAX International Inc., of Yakima, Wash. (undated, but accessed online Mar. 19, 2019) (“YAAX chart”). The YAAX chart indicates that the naked eye visibility threshold is 40 microns.
In some embodiments, the bonding agent is a bonding agent for elastomers that includes at least a polymer-adhesive organic solvent. In some further embodiments, the polymer-adhesive organic solvent includes at least a nitrogen substituted aromatic crossliner of a natural or a synthetic blend.
In some embodiments, the at least one coating 208 includes at least an additional coating 206 that includes at least a silane primer, wherein the silane primer of the at least an additional coating is adhered directly to the garnet particles and the bonding agent of the at least one coating is adhered at least one of to the silane primer or to the garnet particles. In some embodiments, the silane primer of the at least an additional coating 206 is a residue remaining on at least some portions of at least some the garnet particles after evaporation of at least some of the silane primer prior to an application of the bonding agent.
In some embodiments, the silane primer includes at least an oil-derived or synthetic polymer that is configured to prepare the plurality of garnet particles for the bonding agent. In some embodiments, the oil-derived or synthetic polymer includes at least an organofunctional silane. In some further embodiments, the organofunctional silane includes at least one or more of toluene, n-butanol, or an ethanol.
In some embodiments, the at least one coating 208 is only a single coating that includes at least the bonding agent and the at least one coating does not include any additional coatings. For example, a first coating including a silane primer may have been applied before application of a bonding agent, but the silane primer having completely evaporated before application of the bonding agent.
Proceeding with reference to
In some embodiments, the garnet tire 200 is one of a truck tire or a passenger tire. In some embodiments, the garnet tire 200 is at least one of a retread tire or a new tire.
In some embodiments, the at least one coating 208 includes at least an additional coating 206 that includes at least a silane primer, wherein the silane primer of the at least an additional coating is adhered directly to the garnet particles and the bonding agent of the at least one coating is adhered at least one of to the silane primer or to the garnet particles.
Now referencing
In some embodiments the first mixing operation 514 of mixing the plurality of garnet particles 104a, 104b with the at least a silane primer 206 includes at least mixing the plurality of garnet particles 104a, 104b with an organofunctional silane. In some further embodiments, mixing the plurality of garnet particles 104a, 104b with the organofunctional silane includes at least mixing the plurality of garnet particles 104a, 104b with an organofunctional silane that includes one or more of toluene, n-butanol, or an ethanol.
In some embodiments, the second mixing operation 516 of mixing the plurality of garnet particles 104a, 104b with the at least a bonding agent 206 for elastomers includes at least mixing the plurality of garnet particles with a nitrogen substituted aromatic crossliner of a natural or a synthetic blend. In some embodiments, the first mixing operation 514 of mixing the plurality of garnet particles 104a, 104b with at least a silane primer 206 includes at least one of dipping the plurality of garnet particles 104a, 104b in the at least a silane primer 206 or spraying the at least a silane primer 206 on the plurality of garnet particles 104a, 104b.
All of the products, tires, and/or methods disclosed and claimed herein can be made and used without undue experimentation in light of the present disclosure. The above discussion of some embodiments is not exhaustive. Instead, one having ordinary skill in the art will appreciate additional alternatives and/or modifications that may be made to the discussed embodiments without departing from the inventive principles. The invention is therefore not intended to be limited by the above discussion but only by the following claims.
