JP7394027B2 - tire - Google Patents

Description

TECHNICAL FIELD The present invention relates to tires.

Tires are sometimes surface-decorated with patterns such as letters, marks, and figures. Further, one example of surface decoration is a code such as a bar code or a QR code (registered trademark) attached to a tire for the purpose of product management or the like.
For example, Patent Document 1 discloses a technology related to a tire identification label using a two-dimensional barcode as a tire identification code.

Here, as a method of decorating a tire, a method of attaching a pattern by printing such as inkjet is known. Decoration by printing has the advantage of being able to add high-definition patterns, and since tires are expected to be distorted during use, the decorative part by printing can follow that distortion. There is an advantage.
However, when decorating by printing, the printed decoration is rubbed and the color of the decorated part becomes lighter over time, which poses a problem in durability.

Furthermore, as a decoration method other than printing, a technique is known in which decoration is performed by forming irregularities on the surface of a tire. For example, Patent Document 2 discloses a technique for providing a barcode for tire identification by forming a plurality of irregularities on the tire surface.

Japanese Patent Application Publication No. 2005-128063 Japanese Patent Application Publication No. 2012-224194

However, with the technique of Patent Document 2, although it is possible to form a simple barcode on the surface of a tire, there is a problem in that it is difficult to attach a high-definition code. Furthermore, when attaching a high-definition code, there is a problem in that the unevenness formed on the tire surface becomes finer and the durability is reduced.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a tire having a highly durable and highly accurate one-dimensional code or two-dimensional code printed thereon.

The present inventors conducted extensive research to achieve the above object. The resin composition film formed on the vulcanized rubber of the tire contains urethane foam and two or more pigments containing at least carbon black, and the carbon black in the resin composition film is decomposed and irradiated with a laser. It has been found that by evaporating the printed one-dimensional code or two-dimensional code, the printed one-dimensional code or two-dimensional code becomes highly accurate and durable.

That is, the tire of the present invention includes a resin composition film formed on vulcanized rubber, the resin composition film containing urethane foam and two or more types of pigments including at least carbon black, A one-dimensional code or a two-dimensional code is printed by irradiation.
With the above configuration, it is possible to obtain a tire having high durability and on which a highly accurate one-dimensional code or two-dimensional code is printed.

Moreover, in the tire of the present invention, it is preferable that the urethane foam is an ester-based urethane foam. This is because the durability of the printed code can be further improved.

Further, in the tire of the present invention, it is preferable that all of the pigments other than the carbon black have a decomposition temperature of 130° C. or higher. This is because the code can be printed with higher precision.

Furthermore, in the tire of the present invention, the two-dimensional code printed on the resin composition film is preferably a stack-type two-dimensional code or a matrix-type two-dimensional code. This is because it is compatible with various two-dimensional codes.

Further, the tire of the present invention preferably further includes an intermediate layer containing butyl-based rubber and formed between the vulcanized rubber and the resin composition film. This is because the durability of the printed code can be further improved.

Furthermore, in the tire of the present invention, the thickness of the intermediate layer is more preferably 0.2 to 0.4 mm. This is because the durability of the printed code can be further improved.

Moreover, in the tire of the present invention, it is preferable that the resin composition film is formed on the sidewall portion. This is because the printed code has high visibility and can be retained for a long period of time.

Furthermore, in the tire of the present invention, it is preferable that the vulcanized rubber contains an anti-aging agent. This is to suppress deterioration of vulcanized rubber.

Furthermore, in the tire of the present invention, it is more preferable that the content of the anti-aging agent in the vulcanized rubber is 6 parts by mass or less based on 100 parts by mass of the rubber component. This is because it is possible to further enhance the durability of the printed code while suppressing deterioration of the vulcanized rubber.

Further, in the tire of the present invention, it is preferable that the content of carbon black in the decorated portion of the resin composition film after the laser irradiation is 0.1% by mass or less. This is because the code can be printed with higher precision.

According to the present invention, it is possible to provide a tire having a highly durable and highly accurate one-dimensional code or two-dimensional code printed thereon.

FIG. 1 is a cross-sectional view schematically showing a portion of a tire according to an embodiment of the present invention, on which a resin composition film is formed. FIG. 2 is a cross-sectional view schematically showing a portion of a tire according to another embodiment of the present invention, on which a resin composition film is formed. It is a flow diagram showing an example of a process of forming a resin composition film on the vulcanized rubber of a tire. It is a photograph showing an image obtained in an example.

<Tires>
An embodiment of the tire of the present invention will be described in detail below.
In addition, in FIGS. 1 and 2, the upper direction of the drawings indicates the outer side of the tire (the outer side in the tire radial direction or the outer side in the tire width direction), and the lower direction in the drawings indicates the inner side of the tire (the inner side in the tire radial direction or the inner side in the tire width direction). shows. Further, in FIGS. 1 to 3, for convenience of explanation, some parts are shown with dimensions and shapes different from the actual ones.

The tire 100 of the present invention is a tire that includes a resin composition film 12 formed on a vulcanized rubber 10, as shown in FIG.
In the present invention, the resin composition film 12 contains a urethane foam 13 and two or more types of pigments including at least carbon black 14, and is printed with a one-dimensional code or a two-dimensional code by laser irradiation. It is characterized by

The carbon black 14 contained in the resin composition film 12 formed on the vulcanized rubber 10 of the tire 100 can be removed by being decomposed and evaporated by laser irradiation. Printing is performed. The one-dimensional code or two-dimensional code can be obtained with high precision by controlling the irradiation position of the laser and controlling the locations where the pigments 14 and 15 are contained in the resin composition film 12. . Furthermore, since the resin composition film 12 contains the urethane foam 13 that has high resin impregnation properties and high flexibility and strength, it can also improve durability when used for a long period of time.

(vulcanized rubber)
As shown in FIG. 1, the tire 100 of the present invention includes vulcanized rubber 10, which is a constituent material of the tire.
The vulcanized rubber 10 is made by vulcanizing a rubber composition, and the composition of the rubber composition can be appropriately selected depending on the type, location, performance, etc. of the required tire. For example, the rubber composition may mainly include a rubber component, a filler, and various components such as a vulcanizing agent, a vulcanization accelerator, and an anti-aging agent. The blending amount of each component can also be appropriately selected depending on the required performance of the tire.

However, in the tire 100 of the present invention, if an excessive amount of anti-aging agent is contained in the vulcanized rubber 10, the anti-aging agent will migrate to the resin composition film 12 over time, leaving the decorated area and the non-decorated area. The color tone of the area may change over time, and sufficient durability may not be obtained. Therefore, the content of the anti-aging agent in the rubber composition is preferably more than 0 parts by mass and less than 6 parts by mass, and more than 1 part by mass and not more than 5 parts by mass, based on 100 parts by mass of the rubber component. is more preferable.

(Resin composition film)
The tire 100 of the present invention includes a resin composition film 12 formed on the vulcanized rubber 10, as shown in FIG.
The resin composition film 12 contains at least urethane foam 13 and has a plurality of holes 13a. These plurality of holes 13a may be granular voids as shown in FIG. 1, or may be layered voids.

From the viewpoint of resin impregnation, the resin composition film 12 contains urethane foam as the resin component (including an elastomer here) of the resin composition film 12, and if necessary, polystyrene, polypropylene, EPDM, etc. (ethylene propylene diene rubber) etc. can also be further contained. Furthermore, the urethane foam is preferably an ester-based urethane foam from the viewpoint of having high strength and being able to further improve the durability of the printed code.

Further, although the urethane foam 13 has a plurality of pores 13a, the cell diameter (average size of the pores 13a) is preferably 600 μm or less, more preferably 550 μm or less, and 500 μm or less. is even more preferable.
If the upper limit value of the cell diameter is within the above range, a sufficient amount of pigment will be present in the pores 13 of the urethane foam 13, and the color tone of the printed one-dimensional code or two-dimensional code will be within the appropriate range. It becomes possible to do so. In addition, from the viewpoint of containing pigment in the pores 13 of the urethane foam 13, the cell diameter is preferably 200 μm or more, and more preferably 300 μm or more.
Note that the pores 13a of the urethane foam 13 can be confirmed by observing the cross section of the laminate 10 with a scanning electron microscope.

The urethane foam 13 included in the resin composition film 12 may be uncompressed or compressed. Note that even when the urethane foam is compressed, the cell diameter of the polyurethane foam is preferably within the above range.

Note that the thickness of the resin composition film 12 can be appropriately set depending on the required performance. For example, when provided on the sidewall or tread portion of a tire, the thickness of the resin composition film 12 is preferably 100 to 500 μm.

As shown in FIG. 1, the resin composition film 12 contains, in addition to the urethane foam 13, two or more types of pigments including at least carbon black 14.
In the tire 100 of the present invention, by using pigments of two or more colors in the resin composition film 12, a desired one-dimensional code or two-dimensional code can be imparted to the laminate through decoration described later. In other words, a high-definition code with excellent design can be obtained. As for the pigment, as shown in FIG. There may be cases where only 100% of pigments are accommodated.

By using carbon black as the pigment, changes in color tone due to migration of the anti-aging agent mentioned above and scratches such as cracks generated on the surface can be made less noticeable. Furthermore, with the decoration described later, it is possible to increase the color contrast between the decorated area and the non-decorated area, and to make the pattern formed on the surface of the laminate clearer. It becomes possible to obtain a two-dimensional code. Furthermore, the carbon black has the advantage of being easily decomposed by laser irradiation.

The carbon black is not particularly limited, and any known carbon black can be used. As the carbon black, various grades of carbon black such as FEF, SRF, HAF, ISAF, and SAF, color carbon black, and the like can be used.
Note that the particle size of the carbon black is not particularly limited. For example, particles having a particle size of 10 to 400 nm can be used.

The pigment contains a pigment other than carbon black (that is, has a color other than black) as a coloring agent. As a result, when decorating (printing) is performed by laser irradiation, which will be described later, a desired color can be imparted to the decorated area, and a one-dimensional code or two-dimensional code with excellent design can be obtained.
In particular, by using a pigment whose color tone is significantly different from that of the carbon black, it is possible to increase the color contrast between the decorated area and the non-decorated area and form a clear one-dimensional code or two-dimensional code. This makes it possible to further enhance the design.

Examples of pigments other than carbon black include inorganic pigments and organic pigments. Since the resin composition film is manufactured through a vulcanization process as described below, it is preferable that the pigment other than the carbon black is one that does not decompose at the vulcanization temperature. The temperature is preferably 130°C or higher, more preferably 150°C or higher, and even more preferably 180°C or higher.

Examples of the inorganic pigment include zinc white, zinc powder, lead zincide, aluminum pigment, lead monoxide, mica-like iron oxide pigment, basic lead chromate, basic lead carbonate, red lead, white lead, and yellow lead. , ocher, kaolin, clay, ultramarine, powder, navy blue, iron oxide pigment, iron oxide powder, cyanamide lead, heavy calcium carbonate, zinc chromate, talc, ground powder, precipitated calcium carbonate, precipitated barium sulfate, iron yellow, powder, titanium dioxide, chalk, barite powder, etc.

Examples of the organic pigments include azo pigments such as soluble azo red, monoazo yellow, monoazo red, disazo yellow, disazo orange, and condensed azo pigments; phthalocyanine pigments such as copper phthalocyanine blue, copper phthalocyanine green, and cobalt phthalocyanine blue. It will be done. Note that from the viewpoint of decomposition temperature, Lysol Red, Bon Maroon Light, Pigment Yellow 5, etc. are excluded from the organic pigments.

The content of the carbon black in the resin composition film is preferably 0.1 to 1.0% by mass, more preferably 0.2 to 0.8% by mass. By setting the content of the carbon black within the above range, the resin composition film can have a desired color tone, and the contrast between the decorated area and the non-decorated area can be increased.
In addition, the content of pigments other than carbon black in the resin composition film is determined by the type of pigment, the color tone of the decorated area (one-dimensional code or two-dimensional code) after decoration, the decorated area and the non-decorated area. The setting can be made as appropriate, taking into account the contrast between the two.

Further, in the tire 100 of the present invention (FIG. 1), the holes 13a of the urethane foam 13 in the resin composition film 12 may be filled with a binder resin (not shown). The binder resin serves to fix the pigment inside the pores. Examples of the binder resin include urethane resin, acrylic resin, fluorine resin, polyvinyl alcohol, polyacrylamide, polyvinyl chloride resin, vinyl acetate resin, butadiene resin, epoxy resin, alkyd resin, melamine resin, chloroprene rubber, etc. can be mentioned. The binder resin may be used alone or in combination of two or more. In particular, it is preferable that the binder resin contains the same resin component as the resin composition film 12, that is, urethane.

The resin composition film 12 may contain additives contained in the resin foam that is the precursor, within a range that does not go against the spirit of the present invention. Examples of such additives are catalysts, blowing agents, defoamers, surfactants, curing agents, and the like.

In the tire 100 of the present invention, a one-dimensional code or a two-dimensional code is printed on the resin composition film 12 by laser irradiation.
In the laser irradiated area (decorated area), carbon black 14 in the pores has disappeared, but pigment 15 other than carbon black remains. Therefore, the decorated area exhibits a color tone derived from the pigment 15 other than carbon black. On the other hand, the area not irradiated with the laser (non-decorated area) exhibits a black color mainly derived from carbon black. That is, by decoration by laser irradiation, a one-dimensional code or a two-dimensional code can be provided to the resin composition film 12 with a color exhibited by the pigment 15 other than carbon black.

By irradiating the resin composition film 12 with a laser, the carbon black 14 is burned out, but the content of the carbon black in the decorated portion is preferably 0.1% by mass or less, and 0.05% by mass. It is more preferably less than % by mass, and most preferably 0% by mass. This is because a high-definition one-dimensional code or two-dimensional code can be displayed more clearly.

Here, the one-dimensional code or two-dimensional code is not particularly limited, but from the viewpoint of forming a higher-definition code, it is preferable that the code is a two-dimensional code. Examples of the two-dimensional code include a stack type two-dimensional code, a matrix type two-dimensional code, and the like.
The stacked two-dimensional code is a two-dimensional code having a structure in which conventional barcodes are vertically stacked. The matrix type two-dimensional code is a two-dimensional code that has a structure in which squares or points called cells are arranged in a lattice pattern, and in order to facilitate position detection of the two-dimensional code, a square frame or an L-shaped frame is used. A distinctive mark called a finder pattern (cutout symbol) is placed inside the symbol. In order to be able to read these two-dimensional codes accurately, it is necessary to print the codes with high precision.

In addition, in the tire of the present invention, the location where the resin composition film is provided is not particularly limited, and can be appropriately selected depending on the application, specifications, etc.
For example, from the viewpoint of high visibility of the printed one-dimensional code or two-dimensional code and retention of the code for a long period of time, the resin composition film can be formed on the sidewall portion of the tire.

(middle class)
As shown in FIG. 2, the tire 100 of the present invention preferably further includes an intermediate layer 11 containing butyl rubber formed between the vulcanized rubber 10 and the resin composition film 12. . This is because it is possible to prevent components such as an anti-aging agent from the vulcanized rubber 10 from migrating to the resin composition film 12 and change the color tone of the resin composition film 12.

The intermediate layer 11 contains butyl rubber. The butyl rubber is not particularly limited, and any known butyl rubber can be used. The butyl rubber may be unmodified butyl rubber or modified butyl rubber such as chlorinated butyl rubber or brominated butyl rubber.
These butyl rubbers may be used alone or in combination of two or more.

Further, the proportion of butyl rubber in the rubber component constituting the intermediate layer 11 can be adjusted as appropriate depending on the performance required of the intermediate layer. For example, the proportion of butyl rubber in the rubber component constituting the intermediate layer 11 is preferably 50% by mass or more, more preferably 60% by mass or more, more preferably 70% by mass or more, It is more preferably 80% by mass or more, and particularly preferably 90% by mass or more.

The rubber component constituting the intermediate layer 11 may include a rubber component other than butyl rubber. Examples of rubber components other than the butyl rubber include copolymers and terpolymers of isobutylene and at least one other comonomer. Useful comonomers include, for example, divinyl aromatic monomers, alkyl substituted vinyl aromatic monomers, and combinations thereof. Divinyl aromatic monomers include vinylstyrene. Alkyl-substituted vinyl aromatic monomers include α-methylstyrene and p-methylstyrene.

The copolymers and terpolymers may be halogenated, such as chlorinated or brominated. For example, halogenated copolymers or terpolymers include those derived from monomers such as p-bromomethylstyrene.

For example, the rubber composition constituting the intermediate layer may be a copolymer of isobutylene and p-methylstyrene, a terpolymer of isobutylene, isoprene, and vinylstyrene, or a brominated copolymer of isobutylene and p-methylstyrene (p-bromomethyl (forming copolymers having styrenyl monomer units), and their halides.

The copolymer of isobutylene and p-methylstyrene contains 0.5 to 25% by weight, or 2 to 20% by weight of p-methylstyrene, based on the total weight of the copolymer, and the remainder of the copolymer is as isobutylene. Also good.
Further, the copolymer of isobutylene and p-methylstyrene may be halogenated with bromine or the like as described above. If halogenated, the copolymer of isobutylene and p-methylstyrene may contain more than 0% by weight and up to 10% by weight, or from 0.3 to 7% by weight of halogen.

The terpolymer of isobutylene, isoprene, and vinylstyrene contains 95 to 99% by weight, or 96 to 98.5% by weight of isobutylene, and 0.5 to 5% by weight, based on the total weight of the terpolymer. 0.8 to 2.5% by weight of isoprene, and the remainder of the terpolymer may be vinylstyrene.

In the case of the halogen, the halogen is contained in an amount of 0.1 to 10% by weight, or 0.3 to 7% by weight, or 0.5 to 3% by weight based on the total weight of the copolymer or terpolymer. Good too.
For example, halogenated and non-halogenated versions of copolymers of isobutylene and p-methylstyrene are available under the trade name "Exxpro™" (ExxonMobil Chemical Co.). Also, for example, a copolymer having mer units of p-bromomethylstyrenyl is available under the trade name "Exxpro 3745" (ExxonMobil Chemical Co.). Also, for example, halogenated and non-halogenated terpolymers of isobutylene, isoprene and vinylstyrene are available under the trade name "Polysar Butyl(TM)"(Lanxess; Germany).

In the rubber composition constituting the intermediate layer, the proportion of rubber components other than butyl rubber in the rubber components may be adjusted as appropriate. The proportion in the rubber component can be, for example, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less, based on 100 parts by mass of the rubber component.

For example, rubber components other than the butyl rubber include copolymers of isobutylene and p-methylstyrene, terpolymers of isobutylene, isoprene, and vinylstyrene, brominated products of copolymers of isobutylene and p-methylstyrene, and halogenated products thereof. It is preferable that one or more rubber components are selected from the group, and the proportion of the rubber component is 20 to 30% by mass of the total rubber components.
Note that the rubber components other than the butyl rubber may be used alone or in combination of two or more.

The rubber composition constituting the intermediate layer may contain known additives such as fillers, oils, stearic acid, crosslinking agents, co-crosslinking agents, etc. in addition to the rubber components. In addition, from the viewpoint of suppressing a change in color tone of the resin composition film, it is preferable that the rubber composition constituting the intermediate layer does not substantially contain an anti-aging agent. "Substantially free" means that the content of anti-aging agent is 0.1 parts by mass or less based on 100 parts by mass of the rubber component.

Moreover, it is preferable that the rubber composition constituting the intermediate layer contains a filler among the above-mentioned additives. Examples of the filler include carbon black, silica, and layered or platy clay minerals. Among these, it is preferable that the rubber composition constituting the intermediate layer contains a layered or plate-like clay mineral. This is because the migration of the anti-aging agent from the vulcanized rubber mentioned above can be further suppressed.

The layered or platy clay mineral may be either a natural product or a synthetic product. Layered or platy clay minerals include, for example, clays such as kaolinic clay, sericite clay, calcined clay, and surface-treated silane-modified clay; montmorillonite, saponite, hectorite, beidellite, stevensite, and non-silane clay minerals. Smectite clay minerals such as tronite; examples include mica, feldspar, vermiculite, halloysite, talc, and swelling mica. Among these, from the viewpoint of suppressing migration of the anti-aging agent from the vulcanized rubber 11, clay, mica, talc and feldspar are preferred, clay, mica and talc are more preferred, clay and talc are even more preferred, and clay is particularly preferred. preferable. Moreover, among the above-mentioned clays, kaolin clay is particularly preferable. These layered or platy clay minerals may be used alone or in combination of two or more.

Considering the bending resistance of the laminate, the average particle size (measured by the Malvern Method) of the layered or platy clay mineral is preferably 50 μm or less, more preferably 0.2 to 30 μm, and 0.2 to 30 μm. More preferably, the thickness is .2 to 5 μm.

When the layered or platy clay mineral is contained in the rubber composition constituting the intermediate layer, the content thereof is preferably 10 parts by mass or more, and 15 parts by mass, based on 100 parts by mass of the rubber component. It is more preferably at least 20 parts by mass, even more preferably at least 25 parts by mass, and particularly preferably at least 25 parts by mass. When the content of the layered or plate-like clay mineral is in the above ratio, migration of the anti-aging agent from the vulcanized rubber can be suppressed. On the other hand, from the viewpoint of improving workability (easiness of kneading) in kneading the rubber composition, the content of the layered or platy clay mineral is preferably 100 parts by mass or less per 100 parts by mass of the rubber component. The amount is preferably 80 parts by mass or less, more preferably 60 parts by mass or less.

The thickness of the intermediate layer is not particularly limited, but is preferably 0.2 to 1.5 mm, more preferably 0.3 to 1 mm. This is because the durability of the printed one-dimensional code or two-dimensional code can be further improved. When the thickness of the intermediate layer is 0.2 mm or more, migration of the anti-aging agent from the vulcanized rubber to the resin composition film can be sufficiently suppressed, and the thickness of the intermediate layer is 1.2 mm or more. When the thickness is 5 mm or less, it is possible to prevent the laminate of the resin composition and the intermediate layer from becoming too thick and causing peeling or the like.

<How to print one-dimensional code or two-dimensional code on tires>
The method of printing a one-dimensional code or two-dimensional code on the tire of the present invention is not particularly limited.
For example, a one-dimensional code or a two-dimensional Dimension code can be printed.

In the pigment supporting step, as shown in FIG. 3(a), pigments 14 and 15 are supported on a urethane foam 13' including a plurality of holes 13a'. As the urethane foam 13', a sheet cut into any shape and size, such as a sheet, can be used.
The urethane foam 13' may include, for example, polystyrene foam, polypropylene foam, EPDM (ethylene propylene diene rubber) foam, etc. in addition to polyurethane foam.
In the present invention, the thickness of the urethane foam 13' can be appropriately selected in consideration of the thickness of the resin composition film 12. For example, the thickness of the polyurethane foam 13' can be 0.5 to 50 mm.

The cell diameter of the urethane foam 13' is preferably 600 μm or less, more preferably 550 μm or less, and even more preferably 500 μm or less. When the upper limit of the cell diameter is within the above range, a sufficient amount of pigment can be supported within the pores. The cell diameter is preferably 200 μm or more, more preferably 300 μm or more. Note that the cell diameter can be determined according to Annex 1 of JIS K6400-1:2004.

Further, the urethane foam 13' may be a flexible foam, a semi-rigid foam, or a rigid foam. The cell structure of the urethane foam 13' is not particularly limited, and may be a closed cell structure, an open cell structure, or a cell structure in which a closed cell structure and an open cell structure are mixed (hereinafter simply referred to as "mixed cell structure"). Either is fine. Among these, the cell structure of the urethane foam 13' is more preferably a closed cell structure from the viewpoint of supporting the pigment.

As a method for making the cells of the urethane foam 13' carry pigments, for example, there is a method of immersing the urethane foam 13' in an impregnating liquid containing the pigments 14 and 15, and making the cells 13a' contain the pigments 14 and 15. be.
In this case, the impregnating liquid containing the pigments 14 and 15 includes at least the pigments 14 and 15 described above and a dispersion medium.
The dispersion medium is at least one of an organic solvent, water, and a binder resin. The dispersion medium can be appropriately selected in consideration of the viscosity of the impregnating liquid, the dispersibility of the pigment, and the like.

Examples of organic solvents include toluene and dimethylformamide.
Examples of the binder resin include urethane resin, acrylic resin, fluorine resin, polyvinyl alcohol, polyacrylamide, polyvinyl chloride resin, vinyl acetate resin, butadiene resin, epoxy resin, alkyd resin, melamine resin, chloroprene rubber, etc. . The binder resin may be used alone or in combination of two or more.
Moreover, when the binder resin is made to coexist with another dispersion medium (organic solvent, water), it is preferable that the binder resin is dissolved in the organic solvent or water. Further, the binder resin may contain known additives such as a crosslinking agent.

The amount of carbon black in the impregnating liquid is preferably 1 part by mass or more, more preferably 1.5 parts by mass or more, based on 100 parts by mass of the dispersion medium. By setting the amount of carbon black within the above range, the laminate (non-decorated area after decoration) can have a desired color tone, and the decorated area (one-dimensional code or two-dimensional code) can have a desired color tone. The contrast between the printed area) and the non-decorated area can be increased. On the other hand, since carbon black absorbs the laser light irradiated in the decorating process described below, if the amount of carbon black is too large, the laminate may be damaged. From the viewpoint of suppressing thermal damage to the laminate, the amount of carbon black blended is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, based on 100 parts by mass of the dispersion medium. From the viewpoint of ensuring the disappearance of carbon black by laser irradiation and increasing the contrast between the decorated area and the non-decorated area, the amount of carbon black blended is 5 parts by mass or less per 100 parts by mass of the dispersion medium. The amount is preferably 3 parts by mass or less, and more preferably 3 parts by mass or less.

In addition, the amount of pigments other than carbon black in the impregnating solution is adjusted by taking into account the type of coloring agent, the color tone of the decorated area, and increasing the contrast between the decorated area and the non-decorated area. be able to.

Furthermore, from the viewpoint of giving the non-decorated area and the decorated area a desired color tone and increasing the contrast, the impregnating liquid contains carbon black (CB) and pigments other than carbon black (CF, including multiple pigments). The ratio (CF/CB, mass ratio) is preferably from 8/2 to 5/5, more preferably from 7/3 to 6/4.
In particular, when the impregnating liquid contains a binder resin, the ratio (BD/PG, mass ratio) of the binder resin (BD, solid content) to the pigment (total of carbon black and other pigments, PG) is The ratio is preferably 100/1 to 100/20.

The method of impregnating the impregnating liquid into the urethane foam 13' includes (i) compressing the urethane foam 13' with pressure, immersing it in the impregnating liquid in the compressed state, and releasing the pressure in the impregnating liquid. (ii) a method in which the urethane foam 13' is immersed in an impregnating liquid, and pressure is applied and released to the resin foam in the immersed state.Impregnation The amount of the impregnating liquid in the resin foam may be adjusted by passing the urethane foam 13' taken out from the liquid between rolls arranged at a predetermined interval.Urethane after impregnation The foam 13' is dried under predetermined conditions (temperature, time, etc.).
Conditions such as the pressure applied to the urethane foam 13', impregnation time, roll spacing, and drying temperature/time are determined by taking into account the amount of pigment supported on the resin foam, the amount of binder resin, ease of handling in subsequent processes, etc. It can be set as appropriate.

In the lamination step, as shown in FIG. 3(b), in the pigment supporting step (FIG. 3(a)), the urethane foam 13' in which the pigments 14 and 15 are supported in the cells 13a' is formed into a vulcanized rubber. The rubber composition 10' is laminated on the rubber composition 10'. When the intermediate layer 11 is provided as shown in FIG. 2, the rubber composition constituting the intermediate layer 11 is placed between the urethane foam 13' and the unvulcanized rubber composition 10' constituting the vulcanized rubber. A molded body containing the material can be placed.

The rubber composition 10' which becomes the vulcanized rubber is obtained by molding the rubber composition constituting the above-mentioned vulcanized rubber by a known method. The rubber composition 10' may be unvulcanized or may be previously vulcanized. Note that, from the viewpoint of interlayer adhesion and suppression of deterioration of vulcanized rubber due to revulcanization, it is particularly preferable that the rubber composition 10' be unvulcanized.

The molded body serving as the intermediate layer is molded from the rubber composition for the intermediate layer described above by a known method. The molded body may be unvulcanized or may be previously vulcanized. Note that, from the viewpoint of interlayer adhesion and suppression of deterioration of the intermediate layer due to revulcanization, it is particularly preferable that the molded body is unvulcanized.
The thickness of the molded body can be set in consideration of the thickness of the intermediate layer when formed into a laminate. For example, a molded body containing a rubber composition can be used to form an intermediate layer having a thickness of 0.1 to 1.5 mm.

In the vulcanization step, as shown in FIG. 3(c), the urethane foam 13 in which the pigments 14 and 15 are supported in the bubbles 13a' formed on the rubber composition 10' in the lamination step (FIG. 3(b)) is used. ' is heated while being compressed. As a result, the rubber composition 10' is vulcanized to form a vulcanized rubber 10, and a resin composition film 12 in close contact with the vulcanized rubber 10 is formed.
Vulcanization conditions (pressure, temperature, etc.) are not particularly limited, and can be appropriately set in consideration of the rubber composition of the vulcanized rubber 10 (and intermediate layer 11).

In a tire equipped with the resin composition film 12 obtained through the vulcanization process (FIG. 3(c)), a one-dimensional code or a two-dimensional code is printed on the resin composition film 12 by laser irradiation in the decorating process. be done. By laser irradiation, the carbon black 14 in the resin composition film 12 absorbs the laser light and disappears. There is no carbon black in the area irradiated with the laser (the printed part of the one-dimensional code or two-dimensional code), and the decorated area takes on the color caused by the coloring agent.

Here, the laser irradiation for printing the one-dimensional code or the two-dimensional code can print the one-dimensional code or the two-dimensional code by controlling the irradiation position. Further, it is also possible to control the locations where the pigments 14 and 15 are contained in the resin composition film 12 and to irradiate the front surface of the resin composition film 12 with laser. However, from the viewpoint of drawing the one-dimensional code or two-dimensional code in the resin composition film 12 with higher precision, it is preferable to print the one-dimensional code or two-dimensional code by controlling the irradiation position.

In order to eliminate the carbon black, the wavelength of the laser beam needs to be within the absorption wavelength range of carbon black. On the other hand, in order to develop a color using a pigment other than carbon black in the decorative region, it is preferable to select a laser beam with a wavelength that is not absorbed by the pigment or is absorbed in a small amount. In addition, in order to maintain a good appearance such as the surface condition of the decorated laminate that has been irradiated with the laser, it is necessary to select a laser beam with a wavelength that is not absorbed by at least the main component of the resin composition film, or whose absorption amount is small. is preferred.
The laser light used may be a fundamental wave or a harmonic wave. Examples of lasers include Nd:YAG laser (wavelength: 1.06 μm), Nd:YOV ₄ laser (wavelength: 1.06 μm), rare earth doped fiber laser, and the like.
Note that laser irradiation conditions such as output and irradiation time can be appropriately set in consideration of the color tone of the decorated area, the contrast between the printed portion of the one-dimensional code or two-dimensional code, and the non-decorated area, and the like.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to the Examples below.

As shown in FIG. 1, in urethane foam 13, a colorant containing 0.5% of carbon black 14 in solid content (“DW1790” manufactured by Dainichiseika Kagyo Co., Ltd.) and 6% of titanium oxide 15 in solid content are added. A resin composition film 12 containing a coloring agent (“DW1012” manufactured by Dainichiseika Kogyo Co., Ltd.) containing .4% was provided on a vulcanized rubber.
After that, using LDF's "UM-2", output: 50% (ratio to max 1W), step size (movement amount): 40 μm (both x and y axes), speed (speed until moving to the next point) : 200mm/min, number of pulses ((number of consecutive irradiations to the same point): 2 times, Q-S frequency (interval of continuous irradiation to the same point): 10kHz, number of times (number of times a series of operations is repeated): 1 time, A YAG laser was irradiated under the following conditions to print a QR code (registered trademark) on the resin composition film 12 on the vulcanized rubber.The printed QR code (registered trademark) is shown in FIG.

It can be seen from FIG. 4 that high-definition QR codes (registered trademark) of various sizes can be printed on the resin composition film 12.
In addition, as a result of scanning each QR code (registered trademark) using a QR reading application on a smartphone, there was no problem with the QR code (registered trademark) with a diameter of 20 mm and the QR code (registered trademark) with a diameter of 10 mm. I was able to scan it.

According to the present invention, it is possible to provide a tire having a highly durable and highly accurate one-dimensional code or two-dimensional code printed thereon.

10 Vulcanized rubber 11 Intermediate layer 12 Resin composition film 13 Urethane foam 14 Carbon black 15 Pigment other than carbon black 100 Tire

Claims (10)

Equipped with a resin composition film formed on vulcanized rubber,
A tire, characterized in that the resin composition film contains urethane foam and two or more types of pigments including at least carbon black, and a one-dimensional code or two-dimensional code is printed by laser irradiation. The tire according to claim 1, wherein the urethane foam is an ester-based urethane foam. The tire according to claim 1 or 2, wherein all of the pigments other than the carbon black have a decomposition temperature of 130° C. or higher. 4. The tire according to claim 1, wherein the two-dimensional code printed on the resin composition film is a stack-type two-dimensional code or a matrix-type two-dimensional code. The tire according to any one of claims 1 to 4, further comprising an intermediate layer containing butyl rubber formed between the vulcanized rubber and the resin composition film. The tire according to claim 5, wherein the intermediate layer has a thickness of 0.2 to 0.4 mm. The tire according to any one of claims 1 to 6, wherein the resin composition film is formed on a sidewall portion. The tire according to any one of claims 1 to 7, characterized in that the vulcanized rubber contains an anti-aging agent. The tire according to claim 8, wherein the content of the anti-aging agent in the vulcanized rubber is 6 parts by mass or less based on 100 parts by mass of the rubber component. The tire according to any one of claims 1 to 9, wherein the content of carbon black in the decorated portion of the resin composition film after the laser irradiation is 0.1% by mass or less.

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