Vehicle tires featuring a polymer-based tire sealant and the use of the tire sealant in vehicle tires

Abstract

The invention relates to a vehicle tire comprising a polymer-based tire sealant applied to the inside of the vehicle tire, wherein the average layer thickness of the applied tire sealant is greater than 4 mm. The invention further relates to the use of such a polymer-based tire sealant in vehicle tires.

Description

[0001] The invention relates to a vehicle tire comprising a polymer-based tire sealant according to the preamble of claim 1 and the use of such a tire sealant in the vehicle tire according to claim 7.

[0002] Polymer-based tire sealants are known in the prior art. For example, DE102007023094B4 discloses a method for manufacturing a tire with a polymer-based sealant, wherein a high-viscosity first sealant component, comprising a rubber component that is either blended or blended with at least one other rubber component, as well as mixing ingredients that are free of a solvent and an activator, is mixed with at least one second sealant component, comprising a low-viscosity and separately produced medium containing at least one activator, to form the tire sealant, whereby crosslinking takes place, combined with the subsequent introduction of the tire sealant into the inside of the tire.

[0003] The use of such a tire sealant for tires with a high load index, particularly for C-tires (commercial tires), such as van and light truck tires, is not known in the prior art. Vans are known in the prior art and are broadly defined as vehicles with raised bodies, high-roof station wagons, and minibuses. Light trucks are also known in the prior art. The use of such a tire sealant in D-, E-, and F-tires is also not known. Tire types C-, D-, E-, and F-tires have a higher load-bearing capacity than P-tires (passenger tires) and therefore have a reinforced construction.

[0004] The object of the invention is to provide a vehicle tire, preferably a C-tire, D-tire, E-tire or F-tire, particularly with a load index of at least 86, preferably for vans or light trucks, which exhibits improved sealing properties. Furthermore, the object of the invention is to improve the driving safety of motor vehicles with vehicle tires, preferably C-tires, D-tires, E-tires or F-tires, preferably with a load index of at least 86.

[0005] The object of the invention is achieved by a vehicle tire having the features of claim 1. Furthermore, the object of the invention is achieved by using such a tire having the features of claim 7.

[0006] The object of the invention is solved by a vehicle tire comprising a polymer-based tire sealant applied to the inside of the vehicle tire, wherein the average layer thickness of the applied tire sealant is greater than 4 mm.

[0007] Surprisingly, it was found that the use of a polymer-based tire sealant in vehicle tires according to the invention, particularly those with a load index of at least 86, leads to improved sealing. Furthermore, it is advantageous that such vehicle tires can be used in vans and / or light trucks and result in improved driving safety.

[0008] The average layer thickness according to the invention is obtained on average over the entire inner surface of the vehicle tire on which the tire sealant is applied. The layer thickness can be verified, for example, by image analysis of an X-ray image of the vehicle tire.

[0009] In one embodiment of the invention, the vehicle tire has a polymer-based tire sealant, in particular produced according to a method described in DE102007023094B, wherein the tire sealant is produced according to a method for producing a tire sealant, wherein a high-viscosity first sealant component, comprising a rubber component that is free of offcuts or blended with at least one further rubber component, as well as mixing ingredients that are free of a solvent and an activator, is mixed with at least one second sealant component, comprising a low-viscosity and separately produced medium containing at least one activator, to form the tire sealant, whereby crosslinking takes place, combined with the subsequent introduction of the tire sealant into the inside of the tire, characterized by at least the following process steps: - the first sealant component is prepared using a twin-screw extruder; - the second sealant component is produced separately on a mixer; - The first sealant component and the second sealant component are separately fed to a metering device by pumping, wherein the pumping and metering of the first sealant component is carried out with a diaphragm metering device and the pumping and metering of the second sealant component is carried out by means of a diaphragm metering device. - now the high-viscosity first sealant component is mixed with the low-viscosity second sealant component in a mixing device to form the tire sealant; - The tire is now preheated before contact with the tire sealant, which accelerates the cross-linking and thus the reaction of the tire sealant. - Subsequently, the tire sealant is applied to the inside of a rotating tire, whereby the application of the tire sealant is carried out in such a way that an endless bead is placed in the tire, which covers the inside of the tire to be covered by means of a coil pattern; - finally, the tire sealant is brought to a solidified state, thus achieving the sealing effect.

[0010] Advantageously, the use of this tire sealant in vehicle tires with a load index of at least 86 leads to improved driving safety in vans and light trucks.

[0011] In a further embodiment of the invention, the layer thickness of the tire sealant is in the range of 4 mm to 8 mm, preferably in the range of 4.5 mm to 8 mm, and particularly preferably in the range of 5 mm to 8 mm. A significant and surprising aspect is that this layer thickness leads to improved sealing of vehicle tires, especially those with a load index of at least 86. Furthermore, the vehicle tire preferably has a layer thickness of at least 4.5 mm or at least 5 mm. A layer thickness of at least 4.5 mm or at least 5 mm is advantageous for C-rated, D-rated, E-rated, or F-rated tires. It has been found to be advantageous that a greater layer thickness leads to improved sealing of these tires.

[0012] In a further embodiment of the invention, the tire sealant has a tan d at 100°C in the range of 0.2 to 0.9, particularly in the range of 0.4 to 0.6. It has proven advantageous that the tire sealant with the density according to the invention is beneficial for vehicle tires with a load index of at least 86 and leads to improved vehicle safety.

[0013] The tan d is measured using a rheometer, e.g., the HAAKE RheoStress 6000 from Thermo Scientific, or validated by cross-checking through MSE CME. The measurement was performed under the following parameters: normal force F 1700 N, temperature 100 °C, shear stress 200 Pa, and frequency 10.00–0.01 Hz.

[0014] In a further embodiment of the invention, the creep behavior of the tire sealant is in the range of 0.2 mm to 6.0 mm, particularly in the range of 2.0 mm to 4.0 mm. The advantage is that the tire sealant exhibiting such creep behavior leads to significantly improved sealing in vehicle tires, especially in vehicle tires with a load index of at least 86.

[0015] The vertical creep behavior of the tire sealant after vulcanization is determined using the following equipment: plug drill, 10 mm diameter; graph paper, approximately 100 mm x 150 mm; precision balance, accuracy ±0.01 g; camera; 400 ml low-profile beaker; stopwatch; drying oven at 125°C. The procedure is as follows: A 10 mm diameter sample is punched out using a plug drill; the balance is tared with the graph paper; the sample is placed in the upper third of the graph paper and then weighed. The sample weight must be within the specified tolerance range of +0.05 g; the sample on the graph paper is photographed; to examine the flow behavior, the graph paper with the sample facing upwards is placed in a 400 ml beaker and heated in a drying oven at 125°C for 30 minutes; after heating, the sample is photographed again.

[0016] In a further embodiment of the invention, the vehicle tire has a load index of at least 86, preferably at least 90, particularly preferably at least 95, and most preferably at least 100. Tires with such a load index are particularly those bearing a designation selected from a group comprising C, D, E, and F markings, which are also referred to as C, D, E, or F tires. Vehicle tires with a C marking are primarily used on commercial vehicles. They are standardized according to ECE R 54 and differ from passenger car tires. The letter C stands, for example, for "Commercial" and indicates the reinforced carcass construction, in which both the carcass and the belts are of a particularly robust design. Preferably, such belt constructions have a 2+2x0.32 HT profile, although other belt constructions are also conceivable.The use of the aforementioned tire sealant in these vehicle tires leads to improved sealant performance with regard to sealing. These tires are manufactured with a multi-ply construction and are used on trucks, vans, off-road vehicles, commercial vehicles, and some SUVs. In a particular embodiment of the invention, the vehicle tire has a load index in the range of 86 to 131, preferably in the range of 90 to 131, and particularly preferably in the range of 95 to 131. It is advantageous that the vehicle tire incorporating such a sealant is beneficial for tires with a higher load index, as it exhibits improved sealing. C-tires have a ply ratio of 6 PR, D-tires 8 PR, E-tires 10 PR, and F-tires 12 PR. The ply ratio is a measure of a tire's load-bearing capacity.

[0017] The invention further relates to the use of a polymer-based tire sealant for a described vehicle tire, wherein the vehicle tire has an internal pressure in the range of 375 kPa to 575 kPa, and the vehicle tire preferably has a load index of at least 86. It has been found to be advantageous that the use of such a tire sealant in such vehicle tires leads to improved vehicle safety. The internal pressure of the vehicle tire can preferably be related to the ply rate. For example, tires with a 6 PR have an internal pressure in the range of 375 kPa. Tires with an 8 PR have an internal pressure in the range of 475 kPa, and tires with a 10 PR have an internal pressure in the range of 575 kPa. Preferably, the vehicle tire incorporating a polymer-based tire sealant is a tire with a ply rate in the range of 6 PR to 10 PR.

[0018] Further advantages and features of the vehicle tire according to the invention, as well as of its use, will become apparent from the dependent claims, which relate to advantageous embodiments of the present invention and are not to be understood as limiting. The invention also encompasses combinations of the features of different dependent claims, insofar as these are technically possible, even if the dependent claims do not relate to each other or if they belong to different claim categories. Furthermore, combinations of preferred and particularly preferred embodiments are also combinable with one another, insofar as these are technically possible. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102007023094B [0002, 0009]

Claims

[1] Vehicle tyres comprising a polymer-based tyre sealant applied to the inside of the vehicle tyre, characterized by that the average layer thickness of the applied tire sealant is greater than 4 mm. [2] Vehicle tyre according to claim 1, characterized by that the layer thickness of the tire sealant is in the range from 4 mm to 8 mm, preferably in the range from 4.5 mm to 8 mm, particularly preferably in the range from 5 mm to 8 mm. [3] Vehicle tyre according to claim 1 or 2, characterized by that the tire sealant has a tan d at 100°C in the range of 0.2 to 0.9, in particular in the range of 0.4 to 0.

6. [4] Vehicle tyre according to one of the preceding claims, characterized by that the creep behavior of the tire sealant is in the range of 0.2 mm to 6.0 mm, in particular in the range of 2.0 mm to 4.0 mm. [5] Vehicle tyre according to one of the preceding claims, characterized bythat the vehicle tire has a load index of at least 86, preferably at least 90, particularly preferably at least 95, most particularly preferably at least 100. [6] Vehicle tyre according to one of the preceding claims, characterized by that the vehicle tire is at least one tire selected from the group of C tires, D tires, E tires and F tires. [7] Use of a polymer-based tire sealant for vehicle tires according to any one of the preceding claims, wherein the vehicle tire has an internal pressure in the range between 375 kPa and 575 kPa, wherein the vehicle tire preferably has a load index of at least 86.