DECORATIVE TIRE AND METHOD FOR PRODUCING SAME

TECHNICAL FIELD

The present invention relates to a decorative tire having a decorative print layer formed on the tire surface and a method for producing the same.

BACKGROUND ART

Hitherto, in order to enhance the designability of a tire, it has been known that a tire label has been attached to the surface of a sidewall portion of the tire. After attaching the tire label, the surface of the tire repeatedly undergoes great deformation during tire running. Therefore, the tire label is required to have high conformability to the deformation. Conformability means that the base material undergoes expansion and contraction in synchrony with deformation of the base material, without causing cracks due to the deformation (hereinafter, the same). Furthermore, since the tire is used outdoors, it is required that peeling between layers due to temperature change, rainfall, or the like does not occur.

In order to solve such a problem, there is proposed a tire label formed by disposing a paint layer on the surface of a base material and laminating a transparent cover layer to cover the paint layer, the base material layer and the cover layer being formed of an elastic material, in which the hardness of the elastic material forming the base material layer is 20 to 70 according to JIS K6253 and the hardness of the elastic material forming the cover layer is 20 to 100 (refer to Patent Document 1). According to the tire label disclosed in Patent Document 1, it is possible to achieve high conformability to deformation during tire running and to prevent peeling between layers due to temperature change, rainfall, or the like.

• • (Patent Document 1) Japanese Unexamined Patent Application, Publication No. 2009-280070

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

However, a decorative tire of the related art is formed by attaching a tire label, which has been designed in advance, to a tire having a three-dimensional shape. The degree of freedom of design is restricted and the decorative tire of the related art has been merely a decorative tire formed by putting a mark, such as a mark of a manufacturer, on the sidewall of the tire. To address such a circumstance, a technology of applying an ink composition containing a coloring material directly onto a tire surface and then curing the ink composition has been demanded. In such a case, as described above, since the surface of the tire repeatedly undergoes great deformation during tire running, the cured film of the ink composition is required to have high conformability to the deformation. Furthermore, since the tire is used outdoors, it is required that peeling between layers due to temperature change, rainfall, or the like is prevented.

The present invention was achieved in view of such circumstances, and an object of the present invention is to provide a decorative tire produced by directly applying an ink composition containing a coloring material onto the tire surface in order to increase the degree of freedom of design.

Means for Solving the Problems

The inventors of the present invention conducted a thorough investigation in order to solve the problems described above, and the inventors found that an active-energy-ray-curable ink composition can be applied to a tire surface and a decorative print layer capable of conforming to the deformation of a tire can be satisfactorily formed by investigating the composition of active-energy-ray-polymerizable monomers contained in the active-energy-ray-curable ink composition, thus completing the present invention. Specifically, the present invention provides the following.

(1) The present invention relates to a decorative tire having a decorative print layer formed on the tire surface, the decorative print layer being a cured film of an active-energy-ray-curable ink composition containing a coloring material, in which the active-energy-ray-curable ink composition contains active-energy-ray-polymerizable monomers and an active-energy-ray polymerization initiator, and the ink composition contains, as the active-energy-ray-polymerizable monomers, a monomer A): a monofunctional monomer having a glass transition point of −30° C. or lower, and a monomer B): a polyfunctional monomer having a glass transition point of 0° C. or lower.

(2) Furthermore, the present invention relates to the decorative tire described in (1), in which the ink composition further contains, as the active-energy-ray-polymerizable monomers, a monomer C): a monofunctional monomer having an alicyclic structure having a glass transition point of from 0° C. to 110° C.

(3) Furthermore, the present invention relates to the decorative tire described in (1) or (2), in which when the active-energy-ray-curable ink composition is formed on a rubber base material having an elastic modulus of 1.0 MPa to 1.5 MPa at the time of 100% elongation when a specimen of JIS No. 3 is prepared to be subjected to a tensile test according to JIS K6251, as a cured film having a thickness of 10 μm, and the cured film-formed base material having this cured film formed thereon is used as a specimen of dumbbell-shaped No. 6 (JIS K6251-5) to perform a tensile test according to the method of JIS K7161 at 25° C. and at a tensile rate of 100 mm/min, the decorative print layer formed on the tire surface has a cured film fracture point elongation, at which the cured film undergoes cracking, of 200% or more.

(4) Furthermore, the present invention relates to the decorative tire described in any one of (1) to (3), in which the thickness of the decorative print layer is 1 m to 100 μm.

(5) Furthermore, the present invention relates to the decorative tire described in any one of (1) to (4), in which a surface protective layer that protects the surface of the decorative print layer is formed on the surface of the decorative print layer.

(6) Furthermore, the present invention relates to the decorative tire described in (5), in which the surface protective layer is a cured film produced by applying a silicone-modified (meth)acrylic emulsion and drying the silicone-modified (meth)acrylic emulsion, and the thickness of the surface protective layer is 1 m to 100 m.

(7) Furthermore, the present invention relates to the decorative tire described in any one of (1) to (6), in which a primer layer is formed between the tire surface and the decorative print layer.

(8) Furthermore, the present invention relates to the decorative tire described in any one of (1) to (7), in which the decorative print layer is formed by an inkjet method.

(9) Furthermore, the present invention relates to a method for producing the decorative tire described in any one of (1) to (7), the method including forming the decorative print layer using an inkjet method.

Effects of the Invention

According to the present invention, it is possible to provide a decorative tire in which cracking or peeling does not occur in a decorative print layer (hereinafter, referred to as “decoration” in some cases) even if expansion and contraction is repeated continuously. Furthermore, since decoration is printed directly onto a tire, the degree of freedom of decoration can be increased.

PREFERRED MODE FOR CARRYING OUT THE INVENTION

Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not intended to be limited to the following embodiments, and the present invention can be carried out by applying appropriate modifications within the intended scope of the present invention.

Decorative Tire

The decorative tire of the present invention has a decorative print layer formed on the tire surface, the decorative print layer being a cured film of an ink composition containing a coloring material.

Decorative Print Layer

The ink composition that constitutes the decorative print layer is an active-energy-ray-curable ink composition containing a coloring material. When a water-based ink composition is used, it is not preferable from the viewpoints that (i) when printing is performed on a tire, since the surface tension of the ink composition is high, the ink composition may not be appropriately applied onto a base material, (ii) when printing is performed on a tire, since the ink composition contains a water-containing solvent, it takes much time until, the ink composition dries, and (iii) when printing is performed on a tire, since it takes a time until the ink composition dries, a plurality of ink compositions each having a different color is mixed on the tire and thus a clear image may not be formed on the tire surface. When a solvent-based ink composition is used, it is not preferable from the viewpoints that (iv) when printing is performed on a tire, the ink composition may cause the base material to be swollen, (v) when printing is performed on a tire, since the ink composition contains a solvent including a high-boiling point solvent, it takes much time until the ink composition dries, and (vi) when printing is performed on a tire, since it takes a time until the ink composition dries, a plurality of ink compositions each having a different color is mixed on the tire and thus a clear image may not be formed on the tire surface.

The decorative print layer may be printed by any methods such as an inkjet method, a spraying method, or a brush coating method, but the inkjet method is preferable from the viewpoint of increasing the degree of freedom of decoration.

[Active-Energy-Ray-Curable Ink Composition]

[Coloring Material]

The coloring material may be any inorganic pigment or organic pigment that is usually used in conventional oily ink compositions, and examples include carbon black, cadmium red, molybdenum red, chrome yellow, cadmium yellow, titanium yellow, titanium oxide, chromium oxide, viridian, Titanium Cobalt Green, Ultramarine Blue, Prussian Blue, Cobalt Blue, diketopyrrolopyrrole, anthraquinone, benzimidazolone, anthrapyrimidine, azo-based pigments, phthalocyanine-based pigments, quinacridone-based pigments, isoindolinone-based pigments, dioxazine-based pigments, indanthrene-based pigments, perylene-based pigments, perinone-based pigments, thioindigo-based pigments, quinophthalone-based pigments, metal complex pigments, aluminum paste, silica, calcium carbonate, magnesium carbonate, clay, precipitated barium sulfate, and pearl pigment.

A preferred dispersed particle size of the pigment of the active-energy-ray-curable ink composition is preferably from 10 nm to 300 nm as a volume average particle size according to a laser scattering method. If the dispersed particle size is less than 10 nm, since light resistance may be decreased, it is not preferable. On the other hand, if the dispersed particle size is more than 300 nm, stable maintenance of dispersion is made difficult, and when precipitation of the pigment occurs, or the inkjet ink is ejected by an inkjet recording apparatus, head clogging may occur, or ejection bending may occur, which is not preferable.

According to the present invention, when a pigment is used, the content thereof may be appropriately adjusted. The content may vary depending on the kind of the pigment, but from the viewpoint of achieving a balance between dispersibility and coloring power, the content of the pigment in the total amount of the ink composition is preferably 0.1% to 20% by mass, and more preferably 0.2% to 10% by mass, in the case of an organic pigment. Furthermore, from the viewpoint of achieving a balance between dispersibility and coloring power, the content is preferably 1% to 40% by mass, and more preferably 5% to 20% by mass, in the case of an inorganic pigment.

[Viscosity]

The viscosity of the active-energy-ray-curable ink composition is preferably from 5 mPa·s to 20 mPa·s, and more preferably from 5 mPa·s to 15 mPa·s, at 40° C. If the viscosity is less than 5 mPa·s, it is not preferable from the viewpoint that when the ink composition is ejected using an inkjet apparatus, ejectability may be reduced. Ejectability means that dot omission of the ink occurs during continuous printing, or disturbance in ejection or the like occurs, so that printing cannot be carried out normally. If the viscosity exceeds 20 mPa·s, even if a mechanism of decreasing the viscosity by heating is incorporated in the head of the inkjet apparatus, it is not preferable from the viewpoint that ejection failure caused by dot omission occurs, and there is a possibility that the ink composition may not be ejected normally.

Furthermore, from the viewpoint of inkjet ejectability and ejection stability, the surface tension of the active-energy-ray-curable ink composition of the present invention is preferably so that the surface tension at 40° C. is 20 mN/m to 40 mN/m.

[Composition]

In order to increase conformability with respect to the tire, the active-energy-ray-curable ink composition contains active-energy-ray-polymerizable monomers and an active-energy-ray polymerization initiator. The active-energy-ray-polymerizable monomers include a monomer A): a monofunctional monomer having a glass transition point of −30° C. or lower, and a monomer B): a polyfunctional monomer having a glass transition point of 0° C. or lower. Furthermore, in addition to the monomers A) and B), it is more preferable for the active-energy-ray-curable ink composition to contain a monomer C): a monofunctional monomer having an alicyclic structure having a glass transition point of from 0° C. to 110° C.

In the present specification, the term “active-energy-ray-polymerizable monomer” refers to a polymerizable monomer having one or more ethylenically unsaturated double bonds.

[Monomer a): Monofunctional Monomer Having Glass Transition Point of −30° C. or Lower]

The active-energy-ray-polymerizable monofunctional monomers include a monomer A), an active-energy-ray-polymerizable monofunctional monomer having an ethylenically unsaturated double bond, which gives a homopolymer having a glass transition point (Tg) of lower than −30° C. (hereinafter, also referred to as “monomer A)”). The monomer A) can increase flexibility and stretchability of the cured film. Flexibility being high means that when the printed object on which a cured film of the ink composition is formed is bent, the cured film is not easily damaged, and stretchability being high means that when the cured film is pulled, the cured film is not easily breakable (hereinafter, the same).

Examples of the monomer A) include 2-ethylhexyl acrylate (Tg=−85° C.), 2-ethylhexylcarbitol acrylate (Tg=−65° C.), 2-methoxyethyl acrylate (Tg=−50° C.), 2-methoxybutyl acrylate (Tg=−56° C.), 4-hydroxybutyl acrylate (Tg=−80° C.), diethylene glycol monoethyl ether acrylate (Tg=−70° C.), ethoxydiethylene glycol acrylate (Tg=−70° C.), isoamyl acrylate (Tg=−45° C.), isodecyl acrylate (Tg=−55° C.), isooctyl acrylate (Tg=−83° C.), isotetradecyl acrylate (Tg=−56° C.), caprolactone acrylate (Tg=−53° C.), methoxytripropylene glycol acrylate (Tg=−75° C.), EO (ethylene oxide)-modified succinic acid acrylate (Tg=−40° C.), and tridecyl acrylate (Tg=−75° C.). Among them, from the viewpoint of having excellent flexibility and adhesiveness and undergoing curing shrinkage, the monomer A) is preferably any one or more monomers selected from isooctyl acrylate, tridecyl acrylate and ethoxydiethylene glycol acrylate.

The content of the monomer A) is preferably from 2% by mass to 65% by mass, more preferably from 5% by mass to 50% by mass, and even more preferably from 10% by mass to 35% by mass, relative to the total amount of the active-energy-ray-polymerizable monomers. If the content is less than 2% by mass, it is not preferable from the viewpoint that when the ink composition is printed on a tire, the ink composition cannot conform to the elongation of the tire, and cracking or peeling may occur in the cured product of the ink composition. If the content is more than 65% by mass, it is not preferable from the viewpoint that when the ink composition is irradiated with a predetermined amount of active energy radiation, there is the possibility that curing of the ink composition may be insufficient.

[Monomer B): Polyfunctional Monomer Having Glass Transition Point of 0° C. or Lower]

The active-energy-ray-polymerizable polyfunctional monomers include monomer B): a polyfunctional monomer having an ethylenically unsaturated double bond, which gives a homopolymer having a glass transition point of 0° C. or lower (hereinafter, also referred to as “monomer B)”). The monomer B) contributes to an enhancement of curability, and since the glass transition point is low, the monomer B) is well-balanced between “curability” and “flexibility or stretchability”. Curability means that since the monomer is polyfunctional, the monomer has high crosslinkability, and can form a cured film with only a small amount of active energy ray irradiation. If Tg is higher than 0° C., it is not preferable from the viewpoint that when printing is performed on a tire, the ink composition cannot conform to the elongation of the tire to be printed, and cracking or peeling may occur in the cured product of the ink composition.

Regarding the monomer B), preferred examples of bifunctional monomers include diacrylates of 11-mole to 32-mole ethylene oxide addition modification products of bisphenol A (hereinafter, referred to as “EO-modified”); polyethylene glycol diacrylates having the number of repetition n of ethylene glycol of 7 to 14; and polypropylene glycol diacrylates having the number of repetition n of propylene glycol of 7 to 1.4. More preferred examples include EO-modified (30) bisphenol A diacrylate (Tg=−42° C.), which is a 30-mole EO addition modification product, polyethylene glycol diacrylate (n=9, Tg=−20° C.), polyethylene glycol diacrylate (n=13 to 14, Tg=−34° C.), polypropylene glycol diacrylate (n=7, Tg=−8° C.), and polypropylene glycol diacrylate (n=12, Tg=−32° C.).

Regarding the monomer B), examples of trifunctional monomers include EO-modified (3) trimethylolpropane triacrylate (Tg=−40° C.), EO-modified (6) trimethylolpropane triacrylate (Tg=−8° C.), EO-modified (9) trimethylolpropane triacrylate (Tg=−19° C.), EO-modified (15) trimethylolpropane triacrylate (Tg=−32° C.), propylene oxide addition modification products (hereinafter, referred to as “PO-modified”) (3) trimethylolpropane triacrylate (Tg=−15° C.), and PO-modified (6) trimethylolpropane triacrylate (Tg=−15° C.).

Among the monomers described above, from the viewpoint of having a cured film having excellent flexibility and curability, a bifunctional monomer having a Tg of −30° C. or lower is preferred, and any one or more monomers selected from polypropylene glycol diacrylate (n=12, Tg=−32° C.), polyethylene glycol diacrylate (n=13 to 14, Tg=−34° C.), and EO-modified (30) bisphenol A diacrylates (Tg=−42° C.) are more preferred.

The content of the monomer B) is preferably from 2% by mass to 30% by mass, more preferably from 5% by mass to 15% by mass, and particularly preferably from 9% by mass to 15% by mass, relative to the total amount of the active-energy-ray-polymerizable monomers. If the content is less than 2% by mass, when the ink composition is cured by irradiating the ink composition with active energy radiation, a large amount of irradiation is required, and there is a possibility that curing cannot be sufficiently achieved with a predetermined amount of active energy ray irradiation. If the content is more than 30% by mass, the viscosity increases, and crosslinkability becomes excessively high, so that there is a possibility that conformability or stretchability may decrease.

When both the monomer A) and the monomer B) are incorporated, a good balance can be achieved between “flexibility or stretchability” and “curability”. When only the monomer A) or only the monomer B) is used, a balance between “flexibility or stretchability” and “curability” cannot be achieved, and an ink composition conforming to a base material having high stretch or elastic properties, such as a tire, cannot be obtained.

[Monomer C): Monofunctional Monomer Having Alicyclic Structure with Glass Transition Point of from 0° C. to 110° C.]

The active-energy-ray-polymerizable monofunctional monomers include monomer C): a monofunctional monomer having an alicyclic structure, which gives a homopolymer having a glass transition point of from 0° C. to 110° C. (hereinafter, also referred to as “monomer C)”). When a monofunctional monomer having an alicyclic structure is incorporated in an appropriate amount while the glass transition point is maintained in the range described above, flexibility and film strength of the cured film are enhanced in a well-balanced manner.

Examples of the monomer C) include isobornyl acrylate (Tg=94° C.), 4-t-butylcyclohexyl acrylate (Tg=34° C.), cyclohexyl acrylate (Tg=15° C.), and dicyclopentenyloxyethyl acrylate (Tq=14° C.). Among them, from the viewpoint of enhancing the balance between flexibility and film strength, the monomer C) is preferably any one or more monomers selected from isobornyl acrylate, 4-t-butylcyclohexyl acrylate, cyclohexyl acrylate, and dicyclopentenyloxyethyl acrylate.

From the viewpoint of appropriately enhancing the balance between flexibility and film strength, the content of the monomer C) is preferably from 20% by mass to 65% by mass, and more preferably from 25% by mass to 55% by mass, relative to the total amount of the active-energy-ray-polymerizable monomers. If the content is less than 20% by mass, there is a possibility that the film strength of the cured product may be decreased, which is not preferable. If the content is more than 65% by mass, although the film strength is increased, conformability or flexibility of the base material is decreased, and there is a possibility that the balance between the film strength and flexibility may be decreased, which is not preferable.

When the monomer C) is also incorporated in addition to the monomer A) and the monomer B), since the “coating film strength” is increased, consequently a cured film which satisfies all of “flexibility or stretchability”, “curability” and “coating film strength” can be obtained.

Furthermore, another monomer may also be appropriately added in addition to the monomers A) to C), to the extent that the object of the present invention can be achieved. For example, a monofunctional monomer that is exemplified by phenoxyethyl acrylate (Tg=−22° C.), lauryl acrylate (Tg=−3° C.), 2-hydroxyethyl acrylate (Tg=−15° C.), stearyl acrylate (Tg=30° C.), dicyclopentenyl acrylate (Tg=120° C.), dicyclopentanyl acrylate (Tg=120° C.), or 1-adamantyl acrylate (Tg=153° C.); or a polyfunctional monomer that is exemplified by 1,4-butanediol diacrylate (Tg=45° C.), tetraethylene glycol diacrylate (Tg=23° C.), dimethyloltricyclodecane diacrylate (Tg=187° C.), trimethylolpropane triacrylate (Tg=62° C.), or pentaerythritol triacrylate (Tg=103° C.) may also be added.

[Active-Energy-Ray-Polymerization Initiator]

The active-energy-ray-curable ink composition contains an active-energy-ray-polymerization initiator. The active energy radiation may be any light radiation such as far-ultraviolet radiation, ultraviolet radiation, near-ultraviolet radiation and infrared radiation; electromagnetic waves such as X-radiation and γ-radiation; an electron beam, a proton beam, and a neutron beam, as long as the active energy radiation is energy radiation that serves as a trigger of a polymerization reaction of a radical, a cation, an anion or the like; however, from the viewpoints of the rate of curing, easily availability of the irradiation apparatus, price and the like, curing by ultraviolet irradiation is preferred. The active-energy-ray-polymerization initiator is not particularly limited as long as the initiator can accelerate a polymerization reaction of a compound having an ethylenically unsaturated double bond in an active-energy-ray-curable ink composition, by irradiation of active energy radiation, and any active-energy-ray-polymerization initiator that is conventionally known can be used. Specific examples of the active-energy-ray-polymerization initiator include, for example, aromatic ketones such as thioxanthone; α-aminoalkylphenones; α-hydroxyketones; acylphosphine oxides; aromatic onium salts; organic peroxides; thio compounds; hexaarylbiimidazole compounds; keto oxime ester compounds; borate compounds; azinium compounds; metallocene compounds, active ester compounds, compounds having carbon-halogen bonds; and alkylamine compounds.

According to the present invention, regarding the active-energy-ray-polymerization initiator, from the viewpoint of accelerating a polymerization reaction and increasing curability, it is preferable to use, among others, one or more selected from the group consisting of acylphosphine oxides, α-hydroxyketones, and α-aminoalkylphenones.

Specific examples of the acylphosphine oxides include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (trade name: IRGACURE 819, manufactured by BASF Japan, Ltd.), bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphenylphoshpine oxide, and (2,4,6-trimethoxybenzoyl)phosphine oxide (trade name: LUCIRIN TPO, manufactured by BASF Japan, Ltd.).

Specific examples of α-hydroxyketone include 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one (trade name: IRGACURE 127, manufactured by BASF Japan, Ltd.), 2-hydroxy-4′-hydroxyethoxy-2-methylpropiophenone (trade name: IRGACURE 2959, manufactured by BASF Japan, Ltd.), 1-hydroxycyclohexyl phenyl ketone (trade name: IRGACURE 184, manufactured by BASF Japan, Ltd.), and an oligo{2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone (for example, trade name: ESACURE ONE, manufactured by Lamberti Group).

Specific examples of α-aminoalkylphenone include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1 (trade name: IRGACURE 369, manufactured by BASF Japan, Ltd.), and 2-dimethylamino-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (for example, trade name: IRGACURE 379, manufactured by BASF Japan, Ltd.).

The amount of the active-energy-ray-polymerization initiator may be any amount capable of appropriately initiating the polymerization reaction of an active energy-ray-polymerizable monomer, and the amount is preferably from 1% by mass to 20% by mass, and more preferably from 3% by mass to 20% by mass, relative to the total amount of the active-energy-ray-curable ink composition.

[Dispersant]

It is preferable that the active-energy-ray-curable ink composition contain a dispersant for dispersing the coloring material. An example of the dispersant may be a polymeric dispersant. The main chain of this polymeric dispersant is formed of a polyester-based chain, a polyacrylic chain, a polyurethane-based chain, a polyamine-based chain, a polycaprolactone-based chain or the like, and the polymeric dispersant preferably has, as a side chain, a polar group such as an amino group, a carboxyl group, a sulfone group or a hydroxyl group, or a salt thereof.

Preferred examples of the polymeric dispersant include polyester-based dispersants, and specific examples include “SOLSPERSE 33000”, “SOLSPERSE 32000”, and “SOLSPERSE 24000” manufactured by Lubrizol Japan, Ltd.; “Disperbyk 168” manufactured by BYK Chemie GmbH; and “AJISPER PB821” manufactured by Ajinomoto Fine-Techno Co., Inc.

The proportion of the polymeric dispersant is preferably, as an active ingredient, from 3 parts by mass to 100 parts by mass, and more preferably from 5 parts by mass to 60 parts by mass, relative to 100 parts by mass of the coloring material. If the proportion is less than 3 parts by mass, the polymeric dispersant cannot disperse the coloring material uniformly, a decrease in the stability of the ink or a decrease in ejectability is possible, which is not preferable. Stability of the ink means stability of the ink properties (for example, viscosity or particle size) obtainable when the ink composition is stored for a long time. If the proportion is more than 100 parts by mass, the proportion of curable components such as polymerizable monomers is relatively reduced so that curability may be decreased, or flexibility of a cured product may be decreased, which is not preferable.

Furthermore, the content of the polymeric dispersant is preferably, as an active ingredient, from 0.1% by mass to 30% by mass, and more preferably from 0.5% by mass to 20% by mass, relative to the total amount of the ink composition. If the content is less than 0.1% by mass, the polymeric dispersant cannot disperse the coloring material uniformly, a decrease in the stability of the ink or a decrease in ejectability is possible, which is not preferable. If the content is more than 30% by mass, the proportion of curable components such as polymerizable monomers is relatively reduced so that curability may be decreased, or flexibility of the cured product may be decreased, which is not preferable.

[Surface Adjusting Agent]

The active-energy-ray-curable ink composition may further include a surface adjusting agent. There are no particular limitations on the surface adjusting agent, but specific examples include “BYK-306”, “BYK-333”, “BYK-371”, and “BYK-377” manufactured by BYK Chemie GmbH, which have dimethylpolysiloxane; “TegoRad 2100”, “TegoRad 2200N” and “TegoRad 2300” manufactured by Evonik Degussa Japan Co., Ltd.

The content of the surface adjusting agent is preferably from 0.1% by mass to 1% by mass relative to the total amount of the ink composition. If the content is less than 0.1% by mass, it is not preferable from the viewpoint that the ink has high surface tension, and the wettability to a tire surface is decreased. Good wettability means that when printing is performed on a base material, the ink composition spreads while wetting, without causing cissing. If the content is more than 1% by mass, since the wet tension of the cured product is lowered, it is not preferable from the viewpoint that when a surface protective layer is formed on the surface of the cured product, cissing may occur.

[Other Additives]

Furthermore, the active-energy-ray-curable ink composition may also include, as other additives, various additives such as a plasticizer, a polymerization inhibitor, a photostabilizer, and an oxidation inhibitor. A solvent can be added to the extent that the object of the present invention is achieved, but it is most preferable that the ink composition does not contain a solvent.

[Cured Film of Active-Energy-Ray-Curable Ink Composition]

The thickness of the cured film is preferably from 1 μm to 100 nm. If the thickness is less than 1 μm, the color density of the decorative print layer is lowered, and there is a possibility that designability or decorativeness may be decreased, or a possibility that properties such as adhesiveness or stretchability may be decreased, which is not preferable. If the thickness is more than 100 μm, when active energy radiation is irradiated onto the ink composition, there is a possibility that the ink composition may not be sufficiently cured in a short time, and therefore, it is not preferable.

Regarding the method for measuring the film thickness of the cured film, an ink composition was applied on a PET film (manufactured by Toyobo Co., Ltd., A4300) under the same coating conditions as those used for the cured film thus produced, and the thickness of the cured film thus obtained was measured using a micrometer. Measurement was carried out at 10 sites for one sample, and the average value of these measured values was designated as the average film thickness. The same also applies to the protective layer and primer that will be described below.

When the above-described active-energy-ray-curable ink composition is formed on a rubber base material having an elastic modulus of 1.0 MPa to 1.5 MPa at the time of 100% elongation when a specimen of JIS No. 3 is prepared to be subjected to a tensile test according to JIS K6251, as a cured film having a thickness of 10 μm, and the cured film-formed base material having this cured film formed thereon is used as a specimen of dumbbell-shaped No. 6 (JIS K6251-5) to perform a tensile test according to the method of JIS K7161 at 25° C. and at a tensile rate of 100 mm/min, the minimum elongation ratio at the time when cracking of the cured film occurs is defined as cured film fracture point elongation (calculated from the formula: (length of printed object when cracking occurred in the cured film−original length of printed object)/original length of printed object×100), and the cured film fracture point elongation is preferably 100% or more (for example, the elongation at the time of stretching the base material to a length of two times the original length is indicated as 100%), and more preferably 200% or more, and is even more preferably from 200% to 1000%. When the cured film fracture point elongation is 200% or more, the cured film can sufficiently conform to the elongation of the tire, and even if the tire is subjected to expansion and contraction, cracking or peeling of the cured film formed on the surface of the tire can be further suppressed. On the other hand, the cured film fracture point elongation of more than 1000% makes it difficult to obtain high strength of the cured film.

Surface Protective Layer

Since the decorative tire is exposed to outdoors, the aesthetic aspect or external appearance of the decorative print layer is considerably impaired by dust, dirt, mud, soot, pitch and the like attached thereto. Furthermore, cracks and the like may be generated at the surface of the decorative print layer and gloss is also impaired due to oxidation or deterioration caused by ultraviolet radiation or the like. Here, it is preferable that a surface protective layer be formed on the decorative tire. Incidentally, the surface protective layer is not limited to the case of being formed on the surface of the decorative print layer, and may be formed directly on the surface of the tire base material, or may be formed on the surface of a primer layer formed on the surface of the tire base material, which will be described below.

Examples of the surface protective layer include a cured film formed by applying an overcoat agent on a cured film of the ink composition and drying the overcoat agent; and a film base material laminated on a tire. When the surface protective layer is formed, the surface of the cured film of the ink composition may have tackiness. Tackiness means that tacky adhesiveness is felt when the surface of the cured film is touched by a finger. In the case of using an overcoat agent, it is preferable to include a silicone-modified (meth)acrylic emulsion having a Tg of 50° C. or lower, from the viewpoint of having excellent conformability to the tire, scratch resistance, chemical resistance or the like.

The amount of active ingredient of the silicone-modified (meth)acrylic emulsion of the overcoat agent is preferably 10% to 80%, and more preferably 20% to 60%. If the amount of active ingredient is less than 10%, it is not preferable from the viewpoint that the drying time for forming the protective layer is lengthened, and thus productivity is decreased. If the amount is 80% or more, it is not preferable from the viewpoint of it being possible that it may be difficult to apply the overcoat agent on the tires.

The thickness of the cured film is preferably from 1 μm to 100 μm. If the thickness is less than 1 μm, it is not preferable because there is a possibility that the cured film may not be protected appropriately. If the thickness is more than 100 μm, it is not preferable from the viewpoint that the drying time for forming the protective layer is lengthened, and thus productivity is lowered.

Examples of commercially available products of an ink composition for forming a surface protective layer that includes the silicone-modified (meth)acrylic emulsion include OP-11, OP-13, OP-39, OP-53, and OP-55 (all manufactured by DNP Fine Chemicals Co., Ltd.). All of these are such that the Tg of the silicone-modified (meth)acrylic emulsion included therein is 50° C. or lower, and therefore, the cured film undergoes satisfactory elongation. Furthermore, the cured film has high conformability to the tire base material even under the conditions in which stress is imposed repeatedly.

Primer Layer

In order to increase adhesiveness between the tire surface and the decorative print layer, a primer layer may be formed between the tire surface and the decorative print layer.

Examples of a primer composition that constitutes the primer layer include the silicone-modified (meth)acrylic emulsion described above, and a resin composition containing a chlorinated polyolefin or the like. From the viewpoint of adhesiveness to the tire base material, conformability, adhesiveness to the active-energy-ray-curable ink composition, flexibility and the like, a primer composition containing a silicone-modified (meth)acrylic emulsion having a Tg of 50° C. or lower is preferred. Furthermore, in order to increase adhesiveness, a curing agent may be added to the primer composition.

The amount of active ingredient of the silicone-modified (meth)acrylic emulsion of the primer composition is preferably 10% to 80%, and more preferably 20% to 60%. If the amount of the active ingredient is less than 10%, it is not preferable from the viewpoint that the drying time for forming a primer layer is lengthened, and thus productivity is lowered. If the amount is more than 80%, it is not preferable from the viewpoint that there is a possibility that it may be difficult to apply the primer composition.

Examples of the curing agent include polyisocyanate. The content of the curing agent is preferably from 1 part by mass to 50 parts by mass relative to 100 parts by mass of the primer composition. If the content is less than 1 part by mass, it is not preferable from the viewpoint that there is a possibility that even if a curing agent is added, adhesiveness may not be significantly increased. If the content is more than 50 parts by mass, it is not preferable because there is a possibility that conformability to the tire base material may be reduced.

In the present invention, the base material to be printed is a colored tire. In this case, it is preferable to incorporate a masking pigment such as a white pigment (for example, titanium oxide or the like), an aluminum paste, or a pearl pigment in the primer composition in order to enhance designability or color developability after printing. Particularly, in order to enhance designability or color developability after printing, a primer composition containing titanium oxide is preferred.

When the primer composition contains titanium oxide, the content of titanium oxide is preferably from 1 part by mass to 50 parts by mass relative to 100 parts by mass of the primer composition. If the content is less than 1 part by mass, there is a possibility that designability or color developability after printing may not be enhanced significantly. If the content is more than 50 parts by mass, the proportion of other resin components is decreased, and thus conformability of the cured film or the like may be decreased.

The thickness of the primer layer is preferably from 1 μm to 100 μm. If the thickness is less than 1 μm, it is not preferable from the viewpoint that even if a primer layer is provided, there is the possibility that adhesiveness between the tire surface and the decorative print layer may not be enhanced significantly, or from the viewpoint that there is a possibility that in the case of a primer layer containing a masking pigment, designability or color developability after printing the decorative print layer may not be enhanced significantly. If the thickness is more than 100 μm, it is not preferable from the viewpoint that the drying time for curing the primer composition is lengthened, and thus productivity is lowered.

Examples of commercially available products of the primer composition include PR-12 and PR-13 (both manufactured by DNP Fine Chemicals Co., Ltd.), both containing titanium oxide and a silicone-modified (meth)acrylic emulsion.

Method for Producing Decorative Tire

Production of the decorative tire of the present invention is carried out by printing the active-energy-ray-curable ink composition onto a tire and then curing the ink composition with active energy radiation.

The decorative print layer may be printed by any methods, such as an inkjet method, a spraying method, or a brush coating method, but the inkjet method is preferable from the viewpoint of increasing the degree of freedom of decoration.

The active energy radiation is preferably light having a wavelength region of 200 nm to 450 nm, and more preferably light having a wavelength region of 250 nm to 430 nm. The light source is not particularly limited, and examples include a high pressure mercury lamp, a metal halide lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, an ultraviolet laser, solar light, and an LED lamp. When active energy radiation is irradiated using such a light source so that the cumulative amount of light is 100 mJ/cm² or more, and preferably 200 mJ/cm² or more, the ink composition can be instantaneously cured.

Meanwhile, when a surface protective layer or a primer layer is formed on the tire, any method that can uniformly apply the composition may be used, and for example, the method may be any of spray coating; coating using a towel, a sponge, a nonwoven fabric, a tissue paper or the like; dispenser coating, brush coating, gravure printing, flexographic printing, silk screen printing, inkjetting, a thermal transfer method, and the like.

EXAMPLES

Hereinafter, the present invention will be described in more detail by way of Examples, but the present invention is not intended to be limited by these descriptions.

[Preparation of Dispersion]

First, regarding yellow, red, indigo and black colors other than white color, dispersants at the proportions indicated in Table 1-1 and Table 1-2 were dissolved in a monofunctional monomer, and pigments at the proportions indicated in Table 1-1 and Table 1-2 were added thereto. The amount of the monofunctional monomer used herein was adjusted so as to obtain a pigment concentration of 12%. Then, the mixed liquids were dispersed using a paint shaker so that the volume average diameter of the pigment would be 300 nm or less, and thus dispersion mixtures were obtained. The particle size was measured using Microtrac Particle Size Analyzer UPA150 (manufactured by Nikkiso Co., Ltd.), which is a particle size distribution analyzer utilizing a laser scattering method. Furthermore, for a white ink, the same method was carried out except that the pigment concentration was adjusted to be 40%.

[Preparation of Ink Composition]

Subsequently, other raw materials were mixed at the proportions indicated in Tables 1-1 and 1-2, and the mixtures were respectively stirred for one hour while heat was applied at 50° C. Thereafter, it was confirmed that there was no solution residue, the mixtures were returned to room temperature, and then the dispersion that had been prepared in advance was added and stirred for one hour. Thereafter, the mixture was filtered using a membrane filter. Thus, ink compositions of Production Examples 1 to 37 were prepared.

Production Examples 1 to 37

TABLE 1-1

Production Example

1

2

3

4

5

6

7

8

9

Tg (° C.)

White

White

White

White

White

White

White

White

White

Pigment

36

38

36

24

18

12.0

12.0

12.0

12.0

−83

25.0

25.0

25

25.0

25.0

25.0

25.0

25.0

25.0

20

25.0

94

26.0

26.0

32.0

32.0

25.0

34

10.4

10.4

20

60

85

16

36.4

10-16

−28

28.78

39.79

28.78

10.79

10.78

10.28

10.28

10.28

10.78

120

−37

10.0

10.0

−34

10.0

−42

10.0

10.0

10.0

10.0

10.0

10.0

107

100

100

100

20

30

20

60

100

20

43

25

45

45

40

20

20

20

20

20

25

23

20

20

80

80

60

20

60

10

10

10

10

92

62

62

67

67

62

62

67

67

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

Production Example

10

11

12

13

14

15

16

17

18

Tg (° C.)

White

White

White

White

White

White

White

White

White

Pigment

36

36

36

25

25

18

18

12.0

12.0

−83

25.0

25.0

25.0

25.0

25

20

25.0

25.0

25.0

25.0

25.0

94

34

16

36.4

35.6

38.7

29.5

10-16

26.4

36.4

29.6

38.7

25.5

−28

10.29

11.28

10.28

10.28

10.78

10.28

11.23

10.26

10.28

120

−37

10.0

10.0

10.0

10.0

−34

10.0

10.0

10.0

10.0

10.0

−42

107

30

20

50

100

20

30

20

50

100

25

45

45

46

25

45

45

20

20

25

20

25

20

25

26

26

80

30

20

60

80

80

80

10

10

67

62

67

67

62

62

67

67

67

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

indicates data missing or illegible when filed

TABLE 1-2

Production Example

19

20

21

22

23

24

25

26

27

28

Tg (° C.)

White

White

White

White

White

White

White

White

White

White

Pigment

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

−83

25.0

25.0

25.0

25.0

25

40

35.28

20

42.78

20

25.0

25.0

94

21.0

21.0

21.0

30

34

63

85

83

83

16

29.5

29.5

29.5

29.5

10-16

18.6

36.73

−28

31.28

18.68

5.78

24.28

33.28

18.28

120

−37

40

125

20

20.3

−34

10.0

10.0

−42

10.0

10.0

10.0

10.0

107

100

100

100

100

100

100

100

100

100

100

20

20

20

20

20

20

20

20

20

20

10

10

10

10

10

10

10

10

10

10

92

92

92

92

92

92

92

92

92

92

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

Production Example

29

30

31

32

33

34

35

36

37

Tg (° C.)

White

White

White

White

White

White

White

White

White

Pigment

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

−83

25.0

48.6

25

25.0

40.8

20

25.0

40.8

94

21.0

21.0

34

85

85

16

29.5

29.5

28

28

28

10-16

29.5

29.5

−28

23.28

35.28

35.28

10.28

10.28

10.28

2.48

2.48

2.48

120

2.60

2.60

2.60

−37

10.0

−34

10.0

−42

10.0

107

10.0

10.0

10.0

8.1

8.1

3.1

100

100

100

100

100

100

100

100

100

20

20

20

20

20

20

20

20

20

10

10

10

10

10

10

10

10

10

92

92

92

92

92

92

92

92

92

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

0.02

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

100.00

(Unit is % by mass)

indicates data missing or illegible when filed

The details of carbon black, a polymeric dispersant A and a polymeric dispersant B are as follows.

TABLE 2

Product name

Manufacturer

Pigment

Carbon black

NEROX 5600

Manufactured by

(BLACK

Evonik Degussa

pigment)

Japan Co., Ltd.

Dispersant

Polymeric

Disperbyk168

Manufactured by

dispersant A

BYK Chemie GmbH

Polymeric

SOLSPERSE33000

Manufactured by

dispersant B

Lubrizol Japan, Ltd.

Examples 1 to 40 and Comparative Examples 1 to 17

TABLE 3

Film

Decorative print layer composition

thickness [μm]

First layer

Second layer

Product name

Manufacturer

First layer

Second layer

Example 1-28

Production Example 1-28

—

—

—

10

—

Example 29-32

Production Example 8

Production

—

—

15

10

Example 4-7

Example 33-36

Production Example 13

Production

—

—

15

10

Example 9-12

Example 37-40

Production Example 18

Production

—

—

15

10

Example 14-17

Comparative

Production Example 29-37

—

—

—

10

—

Example 1-9

Comparative

Water-based inkjet ink Yellow

—

ICY52

Manufactured by

10

—

Example 10

Saiko Epson Corporation

Comparative

Water-based inkjet ink Magenta

—

ICVM52

Manufactured by

10

—

Example 11

Saiko Epson Corporation

Comparative

Water-based inkjet ink Cyan

—

ICC52

Manufactured by

10

—

Example 12

Saiko Epson Corporation

Comparative

Water-based inkjet ink Black

—

ICBK52

Manufactured by

10

—

Example 13

Saiko Epson Corporation

Comparative

Solvent-based inkjet ink Yellow

—

ECO-SOL MAX ESL3-YE

Manufactured by

10

—

Example 14

Roland DG Corporation

Comparative

Solvent-based inkjet ink Magenta

—

ECO-SOL MAX ESL3-MG

Manufactured by

10

—

Example 15

Roland DG Corporation

Comparative

Solvent-based inkjet ink Cyan

—

ECO-SOL MAX ESL3-CY

Manufactured by

10

—

Example 16

Roland DG Corporation

Comparative

Solvent-based inkjet ink Black

—

ECO-SOL MAX ESL3-BK

Manufactured by

10

—

Example 17

Roland DG Corporation

[Production of Printed Object]

1. Production of Printed Objects Related to Examples

A printed object was produced using, as a base material, a rubber base material having an elastic modulus of 1.2 MPa at the time of 100% elongation when a specimen of JIS No. 3 is prepared to be subjected to a tensile test according to JIS K6251, in order to submit the printed object to a table evaluation. A composition that constitutes a decorative print layer as indicated in Table 3 was printed on the surface of a rubber base material by an inkjet method under the conditions of a resolution of 720 dpi so that the average film thickness would be a thickness indicated in Table 3 (the layer configuration was as described in Table 4-1 and Table 4-2, and Examples 1 to 34 were produced thereby). The ink compositions were cured using a SubZero system (UV lamp system, manufactured by Integration Technology, Ltd., D valve, power output: 100 W/cm), under the conditions of a cumulative amount of light of 640 mJ/cm², a peak illuminance of 640 mW/cm², and a rate of conveyance of 18 m/min. Measurement of the cumulative amount of light and the peak illuminance was carried out using an ultraviolet actinometer, UV-351 (manufactured by Orc Manufacturing Co., Ltd.). Thereby, decorative print layers were produced.

Incidentally, the table evaluation is carried out using the above-described rubber base material.

2. Production of Printed Objects Related to Comparative Examples

Decorative print layers were produced by printing at a resolution of 720 dpi for Comparative Examples.

[Evaluation of Printability of Decorative Print Layer]

Evaluation of printability of the decorative print layer was carried out by evaluations of three items, that is, wettability, swelling of the base material, and image reproducibility. Hereinafter, without being limited to evaluation of printability of the decorative print layer, in regard to evaluations of various items, there are areas where “◯ and x”-based evaluations and “◯, Δ and x”-based evaluations are carried out, but the ranges of the evaluation results that are practically usable will be defined to be limited to ◯ for the “◯ and x”-based evaluations, and to ◯ and Δ for the “◯, Δ and x”-based evaluations.

[Wettability]

In regard to wettability, evaluation was carried out by visually observing whether or not the base material was wetted with the ink composition when the ink composition was dropped onto the base material using a dropper. The results are presented in Tables 4-1 and 4-2. When comparing cases immediately after dropping, 30 seconds after dropping, a sample in which the ink composition spread while wetting was rated as “◯”, and a sample in which the ink composition did not spread while wetting was rated as “x”.

[Swelling of Base Material]

In regard to swelling of the base material, evaluation was carried out by visually observing whether or not the ink composition caused the base material to be swollen when the ink composition was dropped onto the base material using a dropper. The results are presented in Tables 4-1 and 4-2. When the ink composition was wiped off 30 seconds after dropping, a sample which exhibited no change in the external appearance of the base material was rated as “◯”, and a sample which exhibited change in the external appearance of the base material was rated as “x”.

[Image Reproducibility]

In regard to image reproducibility, after the ink composition was printed on the base material by the inkjet method, evaluation was carried out by visually observing whether or not a clear image could be formed without dots of the ink compositions being mixed with each other on the base material. The results are presented in Tables 4-1 and 4-2. A sample in which the ink compositions were not mixed with each other was rated as “◯”, and a sample in which the ink compositions were mixed with each other was rated as “x”.

[Evaluation of Adhesiveness]

Evaluation of adhesiveness was carried out by two cases, that is, absence of cross cut and presence of cross cut.

[Absence of Cross Cut]

In the case of the absence of cross cut, a Cellophane adhesive tape was attached to a decorative print layer after being cured, the surface protective layer and the Cellophane adhesive tape were caused to adhere sufficiently, and then the Cellophane adhesive tape was peeled off at 90°. The extent of adhesion of the surface protective layer to the base material was judged. The results are presented in Tables 4-1 and 4-2. A sample which exhibited no peeling was rated as “◯”, and a sample which exhibited peeling was rated as “x”.

[Presence of Cross Cut]

In the case of presence of cross cut, evaluation was carried out according to ASTM D3359. A coating film after being cured was cross-cut into 100 squares with a 1 mm interval and then the Cellophane adhesive tape was attached to the cross-cut portion. Then, after the coating film and the Cellophane adhesive tape were caused to adhere sufficiently, the Cellophane adhesive tape was peeled off at 900. The extent of adhesion of the coating film to the base material was judged. The results are presented in Tables 4-1 and 4-2. A sample in which the extent of peeling was less than 5% was rated as “◯”, a sample in which the extent of peeling was more than or equal to 5% and less than 15% was rated as “Δ”, and a sample in which the extent of peeling was more than 15% was rated as “x”.

[Evaluation of Bending Resistance]

Evaluation of bending resistance was carried out with two types of test, that is, a 90° bending test and a dynamic fatigue test.

[90° Bending Test]

The 90° bending test was carried out by visually evaluating the presence or absence of cracks in a cured film when a printed object of Example or Comparative Example was bent by 90°. The results are presented in Tables 4-1 and 4-2. A sample which exhibited no cracks was rated as “◯”, a sample which exhibited cracks in a very small portion was rated as “Δ”, and a sample which exhibited cracks over the entire surface was rated as “x”.

[Dynamic Fatigue Test]

The dynamic fatigue test was carried out by repeating expansion and contraction of ±30% at a speed (4 Hz) of reciprocation of four times a second. The results are presented in Tables 4-1 and 4-2. A sample which exhibited no cracks when the expansion and contraction was repeated 60,000 times or more was rated as “◯”, a sample which exhibited cracks in a very small portion when the expansion and contraction was repeated 60,000 times was rated as “Δ”, and a sample which exhibited cracks when the expansion and contraction was repeated less than 60,000 times was rated as “x”.

[Evaluation of Stretchability]

Evaluation of stretchability was carried out as follows. The printed object was used as a specimen of dumbbell-shaped No. 6 (JIS K6251-5) to be elongated up to 200% at 25° C. and at a tensile rate of 100 mm/min according to the method of JIS K7161. Then, the presence or absence of cracks in the coating film was evaluated at that time. The results are presented in Tables 4-1 and 4-2. A sample which exhibited no cracks was rated as “◯”, a sample which exhibited cracks in some portions was rated as “Δ”, and a sample which exhibited cracks over the entire surface was rated as “x”. Furthermore, evaluations were carried out on the presence or absence of cracks when the specimen was elongated up to 300% at 25° C. under the same condition and when the specimen was elongated up to 300% at 5° C. under the same condition.

[Evaluation of Water Resistance]

Water resistance was evaluated by immersing a printed object in tap water at room temperature for one week, and by performing the 90° bending test described above while the printed object obtained thereafter was still wet. Furthermore, the printed object was immersed for one week, and the external appearance of the printed object after being dried was evaluated. The results are presented in Tables 4-1 and 4-2. In regard to the 90° bending test, evaluation was performed in the same manner as in the [Evaluation of bending resistance]. Regarding the external appearance, a sample which exhibited no change was rated as “◯”, a sample which exhibited a change but did not exhibit any peeling of the coating film was rated as “Δ”, and a sample which exhibited peeling of the coating film was rated as “x”.

Evaluation of Scratch Resistance

Evaluation of scratch resistance was carried out by evaluating the external appearance when a sample was rubbed 100 times in a reciprocating manner with a Polybrush. The results are presented in Tables 4-1 and 4-2. A sample which exhibited no change in the external appearance was rated as “◯”, a sample which exhibited scratches in the coating film was rated as “Δ”, and a sample which exhibited peeling of the coating film was rated as “x”.

TABLE 4-1

Example

1

2

3

4

5

6

7

8

9

Table

Decorative

Second layer

—

—

—

—

—

—

—

—

—

evaluation

print layer

Color

—

—

—

—

—

—

—

—

—

configuration

First layer

1

2

3

4

5

6

7

8

9

Color

White

White

White

Yellow

Red

Indigo

Black

White

Yellow

Printability of

Wettability

◯

◯

◯

◯

◯

◯

◯

◯

◯

decorative

Swelling of base

◯

◯

◯

◯

◯

◯

◯

◯

◯

print layer

material

Image

◯

◯

◯

◯

◯

◯

◯

◯

◯

reproducibility

Adhesiveness

Absence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Presence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Bending

90° bending

◯

◯

◯

◯

◯

◯

◯

◯

◯

resistance

Dynamic fatigue test

◯

◯

◯

◯

◯

◯

◯

◯

◯

Stretchability

200%/25° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

300%/25° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

300%/5° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

Water

Bending resistance

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

resistance

External appearance

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Scratch resistance

Polybrush 100 times

Δ

Δ

Δ

◯

◯

◯

◯

◯

◯

Example

10

11

12

13

14

15

16

17

18

19

Table

Decorative

Second layer

—

—

—

—

—

—

—

—

—

—

evaluation

print layer

Color

—

—

—

—

—

—

—

—

—

—

configuration

First layer

10

11

12

13

14

15

16

17

18

19

Color

Red

Indigo

Black

White

Yellow

Red

Indigo

Black

White

White

Printability of

Wettability

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

decorative

Swelling of base

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

print layer

material

Image

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

reproducibility

Adhesiveness

Absence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Presence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Bending

90° bending

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

resistance

Dynamic fatigue

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

test

Stretchability

200%/25° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

300%/25° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

300%/5° C.

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

Water

Bending

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

resistance

resistance

External

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

appearance

Scratch

Polybrush 100

◯

◯

◯

◯

◯

◯

◯

◯

◯

◯

resistance

times

Example

20

21

22

23

24

25

26

27

28

Table

Decorative

Second layer

—

—

—

—

—

—

—

—

—

evaluation

print layer

Color

—

—

—

—

—

—

—

—

—

configuration

First layer

20

21

22

23

24

25

26

27

28

Color

White

White

White

White

White

White

White

White

White

Printability of

Wettability

◯

◯

◯

◯

◯

◯

◯

◯

◯

decorative

Swelling of base

◯

◯

◯

◯

◯

◯

◯

◯

◯

print layer

material

Image

◯

◯

◯

◯

◯

◯

◯

◯

◯

reproducibility

Adhesiveness

Absence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Presence of cross

◯

◯

◯

◯

◯

◯

◯

◯

◯

cut

Bending

90° bending

◯

◯

◯

◯

◯

◯

◯

◯

◯

resistance

Dynamic fatigue test

◯

◯

◯

◯

◯

Δ

◯

◯

◯

Stretchability

200%/25° C.

◯

◯

◯

◯

◯

Δ

◯

◯

◯

300%/25° C.

◯

◯

◯

◯

◯

Δ

◯

◯

◯

300%/5° C.

◯

◯

◯

◯

◯

Δ

◯

◯

Δ

Water

Bending resistance

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

resistance

External appearance

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Δ

Scratch resistance

Polybrush 100 times

◯

◯

◯

◯

◯

◯

Δ

Δ

◯

indicates data missing or illegible when filed

TABLE 4-2

Example

29

30

31

32

33

34

Table

Decorative

Second layer

Production

4

5

6

7

 9

10

evaluation

print layer

Example No

configuration

Color

Yellow

Red

Indigo

Black

Yellow

Red

First layer

Production

8

8

8

8

13

13

Example No

Color

White

White

White

White

White

White

Printability

Wettability

◯

◯

◯

◯

◯

◯

of

Swelling of base material

◯

◯

◯

◯

◯

◯

decorative

Image reproducibility

◯

◯

◯

◯

◯

◯

print layer

Adhesive-

Absence of cross cut

◯

◯

◯

◯

◯

◯

ness

Presence of cross cut

◯

◯

◯

◯

◯

◯

Bending

90° bending

◯

◯

◯

◯

◯

◯

resistance

Dynamic fatigue test

◯

◯

◯

◯

◯

◯

Stretchability

200%/25° C.

◯

◯

◯

◯

◯

◯

300%/25° C.

◯

◯

◯

◯

◯

◯

300%/5° C.

◯

◯

◯

◯

◯

◯

Water

Bending resistance

Δ

Δ

Δ

Δ

Δ

Δ

resistance

External appearance

Δ

Δ

Δ

Δ

Δ

Δ

Scratch

Polybrush 100 times

◯

◯

◯

◯

◯

◯

resistance

Example

35

36

37

38

39

40

Table

Decorative

Second layer

Production

11

12

14

15

16

17

evaluation

print layer

Example No

configuration

Color

Indigo

Black

Yellow

Red

Indigo

Black

First layer

Production

13

13

18

18

18

18

Example No

Color

White

White

White

White

White

White

Printability

Wettability

◯

◯

◯

◯

◯

◯

of

Swelling of base material

◯

◯

◯

◯

◯

◯

decorative

Image reproducibility

◯

◯

◯

◯

◯

◯

print layer

Adhesive-

Absence of cross cut

◯

◯

◯

◯

◯

◯

ness

Presence of cross cut

◯

◯

◯

◯

◯

◯

Bending

90° bending

◯

◯

◯

◯

◯

◯

resistance

Dynamic fatigue test

◯

◯

◯

◯

◯

◯

Stretchability

200%/25° C.

◯

◯

◯

◯

◯

◯

300%/25° C.

◯

◯

◯

◯

◯

◯

300%/5° C.

◯

◯

◯

◯

◯

◯

Water

Bending resistance

Δ

Δ

Δ

Δ

Δ

Δ

resistance

External appearance

Δ

Δ

Δ

Δ

Δ

Δ

Scratch

Polybrush 100 times

◯

◯

◯

◯

◯

◯

resistance

Comparative Example

1

2

3

4

5

Table

Decorative

Second layer

Production

—

—

—

—

—

evaluation

print layer

Example No

configuration

Color

—

—

—

—

—

First layer

Production

29

30

31

32

33

Example No

Color

White

White

White

White

White

Printability

Wettability

◯

◯

◯

◯

◯

of

Swelling of base material

◯

◯

◯

◯

◯

decorative

Image reproducibility

◯

◯

◯

◯

◯

print layer

Adhesive-

Absence of cross cut

◯

◯

◯

◯

◯

ness

Presence of cross cut

◯

◯

◯

◯

◯

Bending

90° bending

Δ

Δ

Δ

Δ

Δ

resistance

Dynamic fatigue test

X

X

X

X

X

Stretchability

200%/25° C.

X

X

X

X

X

300%/25° C.

X

X

X

X

X

300%/5° C.

X

X

X

X

X

Water

Bending resistance

Δ

Δ

Δ

Δ

Δ

resistance

External appearance

Δ

Δ

Δ

Δ

Δ

Scratch

Polybrush 100 times

◯

◯

◯

◯

◯

resistance

Comparative Example

6

7

8

9

Table

Decorative

Second layer

Production

—

—

—

—

evaluation

print layer