Low-noise tire, tire inner polyurethane foam sound-absorbing lining composition for manufacturing same, and tire inner polyurethane foam sound-absorbing lining method using same and apparatus therefor

Abstract

The present invention relates to a low-noise tire, a tire inner polyurethane foam sound-absorbing lining composition for manufacturing same, and a tire inner polyurethane foam sound-absorbing lining method using same and an apparatus therefor, and, more specifically, to a low-noise tire, a tire inner polyurethane foam sound-absorbing lining composition for manufacturing same, and a tire inner polyurethane foam sound-absorbing lining method using same and an apparatus therefor, wherein, in order to reduce cavity resonance noise, which is generated as interior noise by the exciting force generated between tire tread and a road surface during driving and transmitted to cavity spaces of tires and axles, a polyurethane foam sound-absorbing lining is formed by simply and quickly foaming spraying, in a liquid state, a polyurethane foam sound-absorbing lining composition at the inner surface of a tire, which corresponds to the tread of the tire, and curing same, and the adhesive strength of the interface between the inner surface of the tire and the polyurethane foam sound-absorbing lining is greatly increased without applying an adhesive primer to the inner surface of the tire so that the inner surface of the tire and the polyurethane foam sound-absorbing lining are not separated from each other, thereby improving the durability of low-noise performance.

Description

Low-noise tire, tire inner polyurethane foam sound-absorbing lining composition for manufacturing same, tire inner polyurethane foam sound-absorbing lining method using same, and device therefor

[0001] The present invention relates to a low-noise tire, a tire inner polyurethane foam sound-absorbing lining composition for manufacturing the same, a tire inner polyurethane foam sound-absorbing lining method using the same, and a device therefor, and more specifically, to a low-noise tire in which a polyurethane foam sound-absorbing lining composition is simply and quickly sprayed in a liquid foam form on the inner surface of the tire corresponding to the tire tread and cured to form a polyurethane foam sound-absorbing lining, and the adhesive force between the inner surface of the tire and the polyurethane foam sound-absorbing lining is significantly increased without applying an adhesive primer to the inner surface of the tire, thereby preventing the inner surface of the tire and the polyurethane foam sound-absorbing lining from being separated, thereby improving low-noise performance and durability, a tire inner polyurethane foam sound-absorbing lining composition for manufacturing the same, and a tire inner polyurethane foam using the same. It relates to a sound-absorbing lining method and its device.

[0002]

[0003] Recently, with the spread of electric vehicles, there is a growing demand for reducing noise caused by tire patterns as well as interior noise to improve ride comfort and create a more comfortable environment as a way to improve automobile quality.

[0004]

[0005] Among these noises, the 200-250 Hz low-frequency resonance noise (cavity resonance noise) that is generated as interior noise by the excitation force generated between the tire tread and the road surface during driving being transmitted to the tire internal (cavity) space and the axle is generated as a sound with a sharp peak inside the vehicle, causing discomfort to the driver and reducing ride comfort.

[0006]

[0007] In particular, with the advent of electric vehicles with virtually no engine noise and the tire sizes mounted on vehicles becoming flatter and larger, tire resonance noise is emerging as an increasingly important issue.

[0008]

[0009] Looking at the prior art for reducing such tire resonance noise, Korean Patent No. 10-1439558 (registration date September 2, 2014) discloses a noise reduction device for a tire, which is formed by fixing a soft polyurethane foam to a ring-shaped band member, wherein the soft polyurethane foam has a density of 7 to 40 kg / ㎥ and a tear strength (N / cm) per unit density (kg / ㎥) of 0.39 to 0.70, and the noise reduction device is maintained on the inner surface of the tire, and is characterized in that it is freely attached to and detached from the tire.

[0010]

[0011] In addition, Korean Patent No. 10-1993303 (registration date: June 20, 2019) discloses a pneumatic tire (2); a body ply (6) forming the skeleton of the tire (2) in parallel with an inner liner (8) on the lower side of the tread (4) in contact with the road surface of the tire (2); a rim (20) mounted on the tire (2) through a bead portion (10) turned up and wrapped by the body ply (6); and a noise reduction member (30) laminated inside between the body ply (6) and the inner liner (8) located on the shoulder portion (16) formed on both the left (L) and right (R) sides in the width direction based on the center line (CL) of the tire (2) to reduce resonance noise generated inside the cavity (12) between the tire (2) and the rim (20) and arranged in an annular shape divided at regular intervals along the circumference; In a pneumatic tire having a noise reduction member, the noise reduction member (30) is formed by overlapping at least one of a noise-prevention tape, a noise-prevention rubber plate, and a noise-prevention fiber tape, or by combining and overlapping a plurality of them. A pneumatic tire having a noise-prevention member is known.

[0012]

[0013] In addition, Korean Patent No. 10-2075314 (registration date February 3, 2020) discloses that 2 to 4 block-shaped porous foam sound absorbers are attached to the inner surface of the tire at a 90-degree angle in the circumferential direction, and the material of the porous foam sound absorbers is porous melamine resin foam.

[0014] The porous foam sound absorber is in the shape of an octahedral block having a horizontal upper length of 10 to 40 mm, a horizontal lower length of 100 to 180 mm, a vertical length of 100 to 180 mm, a height of both ends of 10 to 20 mm, and a center height of 25 to 75 mm, and the porous foam sound absorber includes six rectangular faces and two hexagonal faces, and any one of the six rectangular faces is attached to be in contact with the inner surface of the tire, and the vertical direction of the porous foam sound absorber is consistent with the circumferential direction of the tire, and the porous foam sound absorber has a volume of 36x10 4 A tire for reducing resonance noise is known, characterized in that the porous foam sound absorbing body is attached to the inner surface of the tire using a thermoplastic polyacrylic type adhesive.

[0015]

[0016] In addition, Korean Patent No. 10-2127660 (registration date June 23, 2020) discloses a pneumatic tire comprising a tread portion (100), a sidewall portion (200), and a bead portion (300), wherein the pneumatic tire comprises a sound-absorbing material (350) attached to the inner surface of the tread portion (100) inside the pneumatic tire; and a sound-insulating film (400) fixedly supported by the sound-absorbing material (350) so as to divide the cross-section of the tire together with the sound-absorbing material (350) inside the pneumatic tire, wherein the sound-absorbing material (350) is formed in a pair of ring shapes that are formed in a circular shape in the circumferential direction of the tread portion (100) at a constant interval from each side of the tread portion (100).

[0017]

[0018] In addition, Korean Patent Publication No. 10-2021-0091400 (publication date July 22, 2021) discloses a pneumatic tire including a tread portion (100), a sidewall portion (200), and a bead portion (300), wherein an inner liner (400) is installed on the inner surface of the pneumatic tire, a space portion (500) is formed between the tread portion (100) and the inner liner (400), and a filler (600) is positioned in the space portion (500).

[0019]

[0020] In addition, Korean Patent No. 10-2460711 (registration date: October 25, 2022) discloses a sound-absorbing tire foam tape comprising: a release film; an adhesive layer formed on the lower surface of the release film; a base film formed on the lower surface of the adhesive layer; an adhesive layer formed on the lower surface of the base film; and a sound-absorbing material layer having a porous structure formed on the lower surface of the adhesive layer; wherein the adhesive layer comprises an acrylic adhesive, and the weight average molecular weight of the adhesive included in the adhesive layer is 200,000 to 2,000,000, and the weight average molecular weight of the adhesive included in the adhesive layer is 1,000 to 80,000, and the acrylic adhesive includes an alkyl acrylate having 4 to 17 carbon atoms, and the sound-absorbing material layer includes a polyurethane foam.

[0021]

[0022] However, the above conventional technologies are a method of cutting polyurethane foam, which is a sound-absorbing material, to a size and then attaching it to the inner surface of the tire. In order to attach the polyurethane foam, a primer is applied to the inner surface of the tire and then a worker manually attaches the polyurethane foam.

[0023]

[0024] That is, the step of molding polyurethane foam, the step of applying a primer or adhesive to the inner surface of the tire to strengthen the adhesion of the molded polyurethane foam to the inside of the tire, and the step of attaching the molded polyurethane foam to the inner surface of the tire.

[0025]

[0026] The above method requires multiple production steps, so it takes a long time to produce, increases production costs, and reduces productivity. In addition, if the polyurethane foam is attached incorrectly, there are problems such as imbalance occurring when the tire rotates or the polyurethane foam separating from the tire.

[0027]

[0028] In addition, the polyurethane foam attached to the tire has a narrow and long shape of about 10 cm in width, making it difficult to manually attach it to the inside of the tire, which reduces productivity and increases the possibility of defects due to incorrect attachment.

[0029]

[0030] To improve the above-mentioned problems, a method of foaming the inside of a tire by spraying polyurethane foam in liquid form has been developed.

[0031]

[0032] However, since the main components of tires, rubber, and organic chemical material, polyurethane foam, cannot have strong adhesion with general adhesives, a primer is applied to the inside of the tire and then a foam lining is applied to adhere the polyurethane foam. However, if the primer is not sufficiently applied to the interface between the inner surface of the tire and the polyurethane foam, or if the tire rapidly accelerates or decelerates, the tire and polyurethane foam may separate due to differences in inertial force.

[0033]

[0034] In particular, the above-mentioned problems are becoming more prominent in electric vehicles because they have much greater torque and superior rapid acceleration and deceleration performance than conventional diesel or gasoline vehicles.

[0035]

[0036] The present invention, in order to solve the above-mentioned conventional problems, provides a low-noise tire having improved low-noise performance and durability by simply and quickly spraying a polyurethane foam sound-absorbing lining composition in a liquid foam form on the inner surface of the tire corresponding to the tire tread and curing the composition to form a polyurethane foam sound-absorbing lining, and by significantly increasing the adhesive strength between the inner surface of the tire and the polyurethane foam sound-absorbing lining interface without applying an adhesive primer to the inner surface of the tire so that the inner surface of the tire and the polyurethane foam sound-absorbing lining do not separate, and a tire inner polyurethane foam sound-absorbing lining composition for manufacturing the same, and a tire inner polyurethane foam sound-absorbing lining method and device using the same.

[0037]

[0038] The present invention aims to solve the above technical problem, and in order to reduce cavity resonance noise generated as interior noise due to the excitation force generated between the tire tread and the road surface during driving being transmitted to the tire internal (cavity) space and the axle, a polyurethane foam sound-absorbing lining composition is formed by spraying a liquid foam and curing the polyurethane foam sound-absorbing lining composition on the inner surface of the tire corresponding to the tire tread without applying an adhesive primer, and the polyurethane foam sound-absorbing lining composition comprises: 100 parts by weight of a mixed polyol in which diethylene glycol: an amine polyol having a molecular weight of 400: an amine polyol having a molecular weight of 2000 is mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 30 to 40 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent; A technical solution is to provide a tire inner polyurethane foam sound-absorbing lining composition comprising: 0.5 to 1.5 parts by weight of a urethane reaction catalyst mixed with 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a foaming agent; 0.05 to 0.15 parts by weight of a foaming catalyst; and 1 to 3 parts by weight of a cell opener.

[0039]

[0040] The above chain extender is technically a solution using 1,4-butanediol (1,4-BD).

[0041]

[0042] The technical solution is that the above foaming catalyst is diethyl toluene diamine (DETDA).

[0043]

[0044] The technical solution is that the foaming agent is water.

[0045]

[0046] The above tire inner polyurethane foam sound-absorbing lining composition has a technical solution in which the open cell bubble opening rate after foaming and curing is 92%.

[0047]

[0048] The above tire inner polyurethane foam sound-absorbing lining composition is a technical solution in which the composition includes a black pigment.

[0049]

[0050] In addition, the present invention comprises a step of preparing a polyol premix including 100 parts by weight of a mixed polyol in which diethylene glycol: amine polyol having a molecular weight of 400: amine polyol having a molecular weight of 2000 are mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 0.5 to 1.5 parts by weight of a curing catalyst in which 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol are mixed; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a blowing agent; 0.05 to 0.15 parts by weight of a blowing catalyst; and 1 to 3 parts by weight of a cell opener; A technical solution is provided for a tire interior polyurethane foam sound-absorbing lining method, comprising the steps of: preparing 30 to 40 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent based on 100 parts by weight of the above polyol premix; introducing the polyol premix and the methylene diphenyl diisocyanate (MDI) curing agent into a foaming mixer chamber and mixing them to produce a tire interior polyurethane foam sound-absorbing lining composition as a foaming stock; and forming a polyurethane foam sound-absorbing lining by spraying the internal polyurethane foam sound-absorbing lining composition in a liquid foam form on the inner surface of the tire corresponding to the tire tread and curing the same.

[0051]

[0052] The above tire inner surface liquid foam spray is a technical solution in which foam is sprayed on the inner surface of a tire rotating at a constant speed by a foam spray nozzle spaced a certain distance from the inner surface of the tire at a constant discharge amount for a certain period of time according to the speed of one rotation.

[0053]

[0054] The above tire inner surface liquid foam spray is a technical solution that sprays foam while the inner surface of the tire is heated to 80 to 100°C, thereby improving the adhesive strength between the inner surface of the tire and the interface of the polyurethane foam sound-absorbing lining, thereby preventing separation.

[0055]

[0056] A technical solution comprises a step of punching with a needle brush to form pores in a cured film formed on the surface of a polyurethane foam sound-absorbing lining formed by spraying liquid foam on the inner surface of the tire and curing, or punching a logo design with a logo-designed needle brush.

[0057]

[0058] In addition, the present invention provides a technical solution for a low-noise tire manufactured by the method for producing a polyurethane foam sound-absorbing lining inside the tire.

[0059]

[0060] In addition, the present invention provides a technical solution for a tire interior polyurethane foam sound-absorbing lining device, which comprises a polyurethane foaming machine and a tire rotating jig, wherein the polyurethane foaming machine comprises a polyol premix tank, a methylene diphenyl diisocyanate (MDI) curing agent tank, and a foaming spray nozzle having a foaming mixer chamber therein, so that a polyol premix supplied from the polyol premix tank and a curing agent supplied from the methylene diphenyl diisocyanate (MDI) curing agent tank are mixed in the foaming mixer chamber, and a tire interior polyurethane foam sound-absorbing lining composition, which is a foaming raw material, is foam-sprayed through the foaming spray nozzle onto the inner surface of a tire rotated by the tire rotating jig at a constant discharge amount for a constant time according to one rotation speed.

[0061]

[0062] The above tire rotating jig comprises a pair of rotating rods on which tires are placed and a pair of motors connected thereto, and the technical solution is configured such that when the motors are operated, the pair of rotating rods rotate, and as the rotating rods rotate, the tires placed thereon rotate in one direction.

[0063]

[0064] The above tire rotating jig comprises a rotating shaft that moves horizontally left and right, four radial supports formed at right angles to the radial four-division in front of the rotating shaft, four expansion grip portions formed to extend forward of the ends of the radial supports and to expand / contract radially, respectively, to fix / detach the tire bead portion by radial expansion pressure / contraction, and bead hook portions formed at the ends of the four expansion grip portions, so that the tire gripped by the expansion pressure by the four expansion grip portions and the bead hook portions rotates in one direction as a technical solution.

[0065]

[0066] The low-noise tire of the present invention, the tire inner polyurethane foam sound-absorbing lining composition for manufacturing the same, and the tire inner polyurethane foam sound-absorbing lining method and device using the same have the excellent effect of reducing cavity resonance noise generated as interior noise by transmitting the excitation force generated between the tire tread and the road surface during driving to the tire inner (cavity) space and the axle, by simply and quickly spraying the polyurethane foam sound-absorbing lining composition in a liquid foam form on the inner surface of the tire corresponding to the tire tread and curing it to form a polyurethane foam sound-absorbing lining, and significantly increasing the adhesive force between the inner surface of the tire and the polyurethane foam sound-absorbing lining interface without applying an adhesive primer to the inner surface of the tire, thereby preventing the inner surface of the tire and the polyurethane foam sound-absorbing lining from being separated, thereby improving the durability of low-noise performance.

[0067]

[0068] Figure 1 is a photograph showing a tire inner polyurethane foam sound-absorbing lining method according to the present invention.

[0069] Figure 2 is a photograph showing the open cell of the tire inner polyurethane foam sound-absorbing lining according to the present invention.

[0070] Figure 3 is a cross-sectional view of the inside of a low-noise tire according to the present invention.

[0071] Figure 4 is a configuration diagram of a tire inner polyurethane foam sound-absorbing lining device according to the present invention.

[0072] Figure 5 is a configuration diagram of a tire rotation jig of a tire inner polyurethane foam sound-absorbing lining device according to the present invention.

[0073] Figure 6 is another tire rotation jig configuration diagram of a tire inner polyurethane foam sound-absorbing lining device according to the present invention.

[0074]

[0075] ** Explanation of symbols **

[0076] 10: Polyurethane foaming machine 11: Polyol premix tank

[0077] 12: Hardener tank 13: Foam spray nozzle

[0078] 20: Tire rotating jig 21,22: Rotating rod

[0079] 23,24: Motor

[0080]

[0081] Hereinafter, the present invention will be described in detail through embodiments and / or drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments and / or drawings described herein.

[0082]

[0083] First, the tire inner polyurethane foam sound-absorbing lining composition of the present invention is to form a polyurethane foam sound-absorbing lining by spraying a liquid foam of the polyurethane foam sound-absorbing lining composition on the inner surface of the tire corresponding to the tire tread without applying an adhesive primer and curing the mixture in a weight ratio of 0.3 to 1:0.3 to 1:0.3 to 1 of diethylene glycol: amine polyol having a molecular weight of 400: amine polyol having a molecular weight of 2000; 30 to 40 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent; It is composed of 0.5 to 1.5 parts by weight of a urethane reaction catalyst mixed with 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a foaming agent; 0.05 to 0.15 parts by weight of a foaming catalyst; and 1 to 3 parts by weight of a cell opener.

[0084]

[0085] In the present invention, the polyol that is the raw material of polyurethane may be an amine polyol obtained by reacting an initiator such as a multifunctional alcohol or aromatic amine having two or more activated hydrogens such as a hydroxyl group (-OH) or an amine group (-NH2) with ethylene oxide (EO) or propylene oxide (PO).

[0086]

[0087] In particular, the present invention uses a mixed polyol in which diethylene glycol: amine polyol having a molecular weight of 400: amine polyol having a molecular weight of 2000 is mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1. The amine polyol is a trivalent amine polyol made by addition reaction of PO or EO to triethanol amine, etc., and a tetravalent amine polyol made by addition reaction of PO or EO to ethylene diamine, etc., and uses amine polyols having a molecular weight of 400 and a molecular weight of 2000, and appropriately uses amine polyols having a molecular weight of 400 and a molecular weight of 2000 so as to obtain a polyurethane foam having both flexibility and rigidity.

[0088]

[0089] At this time, if the amount of amine polyol with a molecular weight of 400 is large, there may be a problem that polyurethane foam is not formed due to the short chain length of the polyol, and if the amount of amine polyol with a molecular weight of 2000 is large, there may be a problem that the flexibility of the polyurethane foam is reduced due to the long chain length of the polyol.

[0090]

[0091] Here, the amine polyol can act as a catalyst in the formation of a urethane bond between a hydroxyl group and an isocyanate group of the polyol composition, thereby enabling rapid curing. In addition, an amine catalyst can be additionally used.

[0092]

[0093] Meanwhile, the diisocyanate that reacts with the mixed polyol is preferably methylene diphenyl diisocyanate (MDI), which provides excellent thermal stability and flame retardancy and can improve workability by improving the curing speed.

[0094]

[0095] The above MDI can be produced by reacting phenylamine and methanal to produce an amine mixture known as MDA (Methylenedianiline), and by reacting the diamine mixture with carbonyl chloride to produce MDI.

[0096]

[0097] In particular, the MDI may be a mixture of isomers, for example, a mixture of 2,4'-MDI isomers, 2,2'-MDI isomers, and 4,4'-MDI isomers may be used, and the MDI isomers contain two or more benzene rings, so they have the advantages of excellent thermal stability and flame retardancy, and a fast curing speed, thereby improving work performance.

[0098]

[0099] The above MDI may contain an NCO content of 20 to 30 wt%. If the NCO content is less than 25 wt%, the polyurethane foam becomes too soft, resulting in reduced hardness and adhesive strength. If the NCO content exceeds 20 wt%, the polyurethane foam becomes too hard, resulting in reduced resonance noise insulation.

[0100]

[0101] In the present invention, 30 to 40 parts by weight of the methylene diphenyl diisocyanate (MDI) curing agent is used for 100 parts by weight of the mixed polyol. If the MDI is less than 30 parts by weight, there may be a problem that the internal structure of the polyurethane foam becomes uneven and the strength decreases due to unreacted polyol, and if it exceeds 40 parts by weight, there may be a problem that sound cannot penetrate the formed polyurethane foam, resulting in a decrease in sound absorption performance.

[0102]

[0103] The urethane reaction catalyst mixed with 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol is a catalyst that promotes the reaction between the mixed polyol and MDI during the polyurethane chain formation reaction, and it is preferable to use 0.5 to 1.5 parts by weight per 100 parts by weight of the mixed polyol.

[0104]

[0105] If the above urethane reaction catalyst is less than 0.5 parts by weight, the reaction may be delayed, resulting in poor curing and a decrease in productivity. If it exceeds 1.5 parts by weight, the reaction may be rapid, resulting in problems such as underfilling and cracking of the foam.

[0106]

[0107] The above chain extender functions to increase the molecular weight of polyurethane by extending or crosslinking the polyurethane chain. In the present invention, the chain extender is not limited in type, but may be selected from the group consisting of ethanolamine, diethanolamine, triethanolamine, 1,4-butanediol, and ethylenediamine, and is preferably 1,4-butanediol.

[0108]

[0109] The above chain extender can be used in an amount of 0.3 to 1 part by weight based on 100 parts by weight of the above mixed polyol compound. If it is less than 0.3 parts by weight, the melting point of the polyurethane foam may be lowered due to insufficient hard segments, which may result in a decrease in heat-resistant aging performance. If it is more than 1 part by weight, the resonance noise absorption effect may be reduced due to an excessive amount of hard segments.

[0110]

[0111] The above-mentioned foaming agent may include at least one selected from the group consisting of a conventional foaming agent that can be used in the present invention, for example, water, hydrofluorocarbon (HFC), methylene chloride, n-butane, isobutane, n-pentane isopentane, dimethyl ether, acetone, and carbon dioxide, taking into consideration various physical properties of the required polyurethane foam when foaming, and is not limited to including a specific component, but it is preferable to use water in the present invention.

[0112]

[0113] The above water blowing agent reacts with methylene diphenyl diisocyanate (MDI) during a urethane reaction to form carbon dioxide, thereby forming pore cells inside the polyurethane foam containing it.

[0114]

[0115] At this time, the water foaming agent can be appropriately selected and used in an appropriate amount according to the known usage method and the required density or other characteristics of the polyurethane foam.

[0116]

[0117] Preferably, since carbon dioxide gas generated by a chemical reaction between water and isocyanate directly affects the size of polyurethane foam cells, the content of the water blowing agent of the present invention may include 1 to 3 parts by weight based on 100 parts by weight of the mixed polyol. If the content of the water blowing agent is less than 1 part by weight, there is a disadvantage that the size of cells in the polyurethane foam containing the water blowing agent may be formed in a manner that is disadvantageous to the vibration transmission absorption rate, and if it exceeds 3 parts by weight, the hard part region of the polyurethane foam may expand due to an increase in urea bonds in the structural walls of the cells forming the polyurethane foam containing the water blowing agent, thereby causing a disadvantage that the vibration transmission absorption rate is reduced.

[0118]

[0119] The above-mentioned foaming catalyst is a catalyst that promotes a saturation reaction between isocyanate and a foaming agent during a foaming reaction, and may be at least one selected from the group consisting of diethyl toluene diamine (DETDA), pentamethylenediethylenetriamine, dimethylcyclohexylamine, tris(3-dimethylamino)propylhexahydrotriamine, and bis(2-dimethylaminoethyl)ether, but is not limited thereto, and diethyl toluene diamine (DETDA) is preferred.

[0120]

[0121] It is preferable to use the foaming catalyst in an amount of 0.05 to 0.15 parts by weight per 100 parts by weight of the mixed polyol compound. If the foaming catalyst is less than 0.05 parts by weight, the reaction may be delayed and foaming may be reduced, and if it exceeds 0.15 parts by weight, there may be a problem of excessive foaming.

[0122]

[0123] The above cell opener is used to prevent carbon dioxide gas expanded by the exothermic reaction of polyurethane foam from being trapped, and is preferably used to weaken the cell membrane by using a polyol or polymer with a high EO content to help form open cells with the internal pressure generated during the polyurethane foam reaction. There is no limitation on using a known cell opener.

[0124]

[0125] In particular, the cell opener may be appropriately selected and used in an appropriate amount according to the known usage method and the required density or other characteristics of the polyurethane foam. Preferably, the content of the cell opener of the present invention may include 1 to 3 parts by weight per 100 parts by weight of the mixed polyol.

[0126]

[0127] In addition, the tire inner polyurethane foam sound-absorbing lining composition may be formulated to include a black pigment.

[0128]

[0129] [Example 1]

[0130] [Manufacture of tire inner polyurethane foam sound-absorbing lining composition of the present invention]

[0131] Diethylene glycol: 100 kg of mixed polyol mixed with amine polyol having a molecular weight of 400 and amine polyol having a molecular weight of 2000 in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 40 kg of methylene diphenyl diisocyanate (MDI) curing agent; 1.5 kg of urethane reaction catalyst mixed with 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol; 1 kg of 1,4-butanediol (1,4-BD); 2 kg of water; 0.1 kg of diethyl toluene diamine (DETDA); 2 kg of cell opener was rapidly and homogeneously stirred in a mixer to prepare a tire inner polyurethane foam sound-absorbing lining composition of the present invention.

[0132]

[0133] [Example 2]

[0134] [Measurement of resonance noise characteristics]

[0135] The tire inner polyurethane foam sound-absorbing lining composition manufactured in the above [Example 1] was foam-sprayed onto the inner surface of the tire as shown in [Fig. 1], cured, and then the resonance noise characteristics were measured. The resonance noise characteristics were measured by a method of measuring from the driver's seat during an actual vehicle driving test, and the measurement results confirmed that there was a resonance noise reduction effect in the low-frequency range of 200 Hz to 250 Hz.

[0136]

[0137] [Example 3]

[0138] [Adhesive strength measurement]

[0139] After the tire inner polyurethane foam sound-absorbing lining manufactured in the above [Example 2] was cured, the adhesive strength of the lining was measured three times using a tack tester, and the average adhesive strength was calculated. The average was 11.5 kgf, confirming that the adhesive strength was excellent.

[0140]

[0141] [Example 4]

[0142] [Open-cell bubble opening rate measurement]

[0143] After curing the tire inner polyurethane foam sound-absorbing lining manufactured in the above [Example 2], the open cell bubble opening rate was measured, and as shown in [Figure 2], it was confirmed that the bubble opening rate reached 92%.

[0144]

[0145] Meanwhile, in another aspect, the present invention comprises the steps of preparing a polyol premix including 100 parts by weight of a mixed polyol in which diethylene glycol: amine polyol having a molecular weight of 400: amine polyol having a molecular weight of 2000 are mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 0.5 to 1.5 parts by weight of a curing catalyst in which 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol are mixed; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a blowing agent; 0.05 to 0.15 parts by weight of a blowing catalyst; and 1 to 3 parts by weight of a cell opener; A method for producing an internal tire polyurethane foam sound-absorbing lining, comprising: a step of preparing 30 to 40 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent based on 100 parts by weight of the polyol premix; a step of introducing the polyol premix and the methylene diphenyl diisocyanate (MDI) curing agent into a foaming mixer chamber and mixing them to produce a tire internal polyurethane foam sound-absorbing lining composition as a foaming stock; and a step of forming a polyurethane foam sound-absorbing lining by spraying the internal polyurethane foam sound-absorbing lining composition in a liquid form on the inner surface of the tire corresponding to the tire tread and curing the same.

[0146]

[0147] At this time, the liquid foam spray on the inner surface of the tire is sprayed at a constant discharge amount for a constant time according to the speed of one rotation by a foam spray nozzle spaced a constant distance from the inner surface of the tire while rotating at a constant speed.

[0148]

[0149] In particular, another feature of the tire inner surface liquid foam spray is that the foam spray is performed while the inner surface of the tire is heated to 80 to 100°C, thereby improving the adhesive strength between the inner surface of the tire and the interface of the polyurethane foam sound-absorbing lining, thereby preventing separation.

[0150]

[0151] Optionally, a step of punching with a needle brush to form pores in the cured film formed on the surface of the polyurethane foam sound-absorbing lining formed by spraying liquid foam on the inner surface of the tire and curing it, or punching a logo design with a logo-designed needle brush may be included.

[0152]

[0153] In addition, the present invention, in another aspect, features a low-noise tire manufactured by the tire inner polyurethane foam sound-absorbing lining method as shown in [Figure 3].

[0154]

[0155] In addition, the present invention, in another aspect, as shown in [Figure 4], comprises a polyurethane foaming machine (10) and a tire rotating jig (20), wherein the polyurethane foaming machine (10) comprises a polyol premix tank (11), a methylene diphenyl diisocyanate (MDI) curing agent tank (12), and a foaming spray nozzle (13) having a foaming mixer chamber therein, so that the polyol premix supplied from the polyol premix tank (11) and the curing agent supplied from the methylene diphenyl diisocyanate (MDI) curing agent tank (12) are mixed in the foaming mixer chamber, and the tire inner polyurethane foam sound-absorbing lining composition according to any one of claims 1 to 6, which is a foaming raw material, is applied to the inner surface of the tire rotated by the tire rotating jig (20) through the foaming spray nozzle (13). It features a tire inner polyurethane foam sound-absorbing lining device configured to spray foam at a constant discharge amount for a constant period of time according to a rotation speed.

[0156]

[0157] At this time, the tire rotation jig (20) is configured to include a pair of rotation rods (21, 22) on which a tire is placed and a pair of motors (23, 24) connected thereto, as shown in [Fig. 5], so that when the motors (23, 24) are operated, the pair of rotation rods (21, 22) rotate, and as the rotation rods (21, 22) rotate, the tire (30) placed thereon rotates in one direction.

[0158]

[0159] In addition, as another embodiment, the tire rotation jig (20) may include a rotation axis (25) that moves horizontally left and right, four radial supports (26) formed at right angles to the radial four-division in front of the rotation axis, four expansion grip parts (27) that extend forward of the ends of the radial supports (26) and expand / contract in the radial direction to fix / detach the tire bead part (31) by radial expansion pressure / contraction, and bead hook parts (28) formed at the ends of the four expansion grip parts (27), so that the tire gripped by the expansion pressure by the four expansion grip parts (27) and the bead hook parts (28) may be configured to rotate in one direction.

[0160]

[0161] The above description is merely an example of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments and / or drawings disclosed in the present invention are not intended to limit the technical idea of ​​the present invention, but rather to explain it, and the scope of the technical idea of ​​the present invention is not limited by these embodiments and / or drawings. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

[0162]

[0163] The low-noise tire of the present invention, the tire inner polyurethane foam sound-absorbing lining composition for manufacturing the same, and the tire inner polyurethane foam sound-absorbing lining method and device using the same have excellent effects of improving low-noise performance and durability by simply and quickly spraying a polyurethane foam sound-absorbing lining composition in a liquid foam form on the inner surface of the tire corresponding to the tire tread and curing the composition to form a polyurethane foam sound-absorbing lining, without applying an adhesive primer to the inner surface of the tire, thereby preventing separation of the inner surface of the tire and the polyurethane foam sound-absorbing lining, thereby improving the adhesive strength between the inner surface of the tire and the polyurethane foam sound-absorbing lining. Therefore, the present invention has industrial applicability.

Claims

1. In order to reduce cavity resonance noise generated as interior noise due to the excitation force generated between the tire tread and the road surface during driving being transmitted to the tire internal (cavity) space and the axle, a polyurethane foam sound-absorbing lining composition is formed by spraying a liquid foam without applying an adhesive primer on the inner surface of the tire corresponding to the tire tread and curing the sprayed polyurethane foam sound-absorbing lining composition, the polyurethane foam sound-absorbing lining composition comprises: 100 parts by weight of a mixed polyol in which diethylene glycol: an amine polyol having a molecular weight of 400: an amine polyol having a molecular weight of 2000 is mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 30 to 40 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent; A tire inner polyurethane foam sound-absorbing lining composition characterized by comprising: 0.5 to 1.5 parts by weight of a urethane reaction catalyst mixed with 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a foaming agent; 0.05 to 0.15 parts by weight of a foaming catalyst; and 1 to 3 parts by weight of a cell opener.

2. In paragraph 1, A tire inner polyurethane foam sound-absorbing lining composition characterized in that the chain extender is 1,4-butanediol (1,4-BD).

3. In paragraph 1, A tire inner polyurethane foam sound-absorbing lining composition characterized in that the above foaming catalyst is diethyl toluene diamine (DETDA).

4. In paragraph 1, A tire inner polyurethane foam sound-absorbing lining composition characterized in that the foaming agent is water.

5. In paragraph 1, The tire inner polyurethane foam sound-absorbing lining composition is characterized in that the open cell bubble opening rate after foaming and curing is 92%.

6. In paragraph 1, The tire inner polyurethane foam sound-absorbing lining composition is characterized in that it is composed of a black pigment.

7. A step of preparing a polyol premix including 100 parts by weight of a mixed polyol in which diethylene glycol, an amine polyol having a molecular weight of 400, and an amine polyol having a molecular weight of 2000 are mixed in a weight ratio of 0.3 to 1: 0.3 to 1: 0.3 to 1; 0.5 to 1.5 parts by weight of a curing catalyst in which 33 wt% of triethylene diamine and 67 wt% of dipropylene glycol are mixed; 0.3 to 1 part by weight of a chain extender; 1 to 2 parts by weight of a blowing agent; 0.05 to 0.15 parts by weight of a blowing catalyst; and 1 to 3 parts by weight of a cell opener; A method for producing a tire interior polyurethane foam sound-absorbing lining, comprising: a step of preparing 50 to 60 parts by weight of a methylene diphenyl diisocyanate (MDI) curing agent based on 100 parts by weight of the polyol premix; a step of introducing the polyol premix and the methylene diphenyl diisocyanate (MDI) curing agent into a foaming mixer chamber and mixing them to produce a tire interior polyurethane foam sound-absorbing lining composition according to any one of claims 1 to 6, which is a foaming stock solution; and a step of forming a polyurethane foam sound-absorbing lining by spraying the tire interior polyurethane foam sound-absorbing lining composition in a liquid foam form on the inner surface of the tire corresponding to the tire tread and curing the same.

8. In paragraph 7, The tire inner surface liquid foam spray is characterized in that the tire inner surface liquid foam spray is sprayed with a constant discharge amount for a constant time according to the speed of one rotation by a foam spray nozzle spaced a constant distance from the tire inner surface while the tire inner surface rotates at a constant speed.

9. In paragraph 7, The tire inner surface liquid foam spray is characterized in that the tire inner surface is foam sprayed while the tire inner surface is heated to 80 to 100°C, thereby improving the adhesive strength between the tire inner surface and the polyurethane foam sound-absorbing lining interface, thereby preventing separation.

10. In paragraph 7, A tire inner polyurethane foam sound-absorbing lining method characterized by including a step of punching with a needle brush to form pores in a cured film formed on the surface of a polyurethane foam sound-absorbing lining formed by spraying liquid foam on the inner surface of the tire and curing, or punching a logo design with a logo-designed needle brush.

11. A low-noise tire characterized by being manufactured by a tire internal polyurethane foam sound-absorbing lining method according to Article 7.

12. A polyurethane foaming machine (10) and a tire rotating jig (20), wherein the polyurethane foaming machine (10) comprises a polyol premix tank (11), a methylene diphenyl diisocyanate (MDI) curing agent tank (12), and a foaming spray nozzle (13) having a foaming mixer chamber inside, wherein the polyol premix supplied from the polyol premix tank (11) and the curing agent supplied from the methylene diphenyl diisocyanate (MDI) curing agent tank (12) are mixed in the foaming mixer chamber to form a foaming solution, wherein the tire inner polyurethane foam sound-absorbing lining composition according to any one of claims 1 to 6 is foamed onto the inner surface of the tire rotated by the tire rotating jig (20) through the foaming spray nozzle (13) at a constant discharge amount for a constant time according to the rotation speed. A tire inner polyurethane foam sound-absorbing lining device characterized in that it is configured to be sprayed 13. In paragraph 12, The tire rotating jig (20) is characterized in that it comprises a pair of rotating rods (21, 22) on which a tire is placed and a pair of motors (23, 24) connected thereto, and when the motors (23, 24) are operated, the pair of rotating rods (21, 22) rotate, and as the rotating rods (21, 22) rotate, the tire (30) mounted thereon rotates in one direction.

14. In paragraph 12, The tire rotating jig (20) is characterized in that it comprises a rotating shaft (25) that moves horizontally left and right, four radial supports (26) formed at right angles in the radial direction in front of the rotating shaft, four expansion grip parts (27) that extend forward of the ends of the radial supports (26) and expand / contract in the radial direction to fix / detach the tire bead part (31) by radial expansion pressure / contraction, and bead hook parts (28) formed at the ends of the four expansion grip parts (27), so that the tire gripped by the expansion pressure by the four expansion grip parts (27) and the bead hook parts (28) is configured to rotate in one direction.

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