JP2003211572A - Retroreflective object formed with image and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel retroreflective object formed with an image by partly removing a mirror surface reflecting layer to improve problems of visibility and durability of the image installed on the retroreflective object, and to provide a method for forming the image. <P>SOLUTION: The retroreflective object formed with the image comprises a first layer having a flat first surface, and a second layer having a retroreflective element layer having a second surface exposed at the mirror surface reflection layer. The method for forming the image comprises the step A of installing a photoreactive resin layer on the mirror surface reflection layer of the second surface, the step B of partly reacting a photoreactive resin by selectively light illuminating, the step C of partly removing the selective region of the photoreactive resin layer, and the step D of forming the image by a partial removal of the mirror surface reflection layer. The method for forming the image comprises the step of forming the image by a partial removal of the mirror surface reflection layer by using the retroreflective object having the first layer having the flat first surface and the retroreflective element layer having the second surface exposed at the mirror surface reflection layer. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to an image-formed retroreflective article and a manufacturing method thereof, and more particularly to a retroreflective article having an image formed by partial removal of a specular reflection layer and a manufacturing method thereof.

[0002] More specifically, the present invention relates to signs such as road signs, construction signs, license plates for vehicles such as automobiles and motorcycles, safety materials such as clothing, life preservers, markings for signs, visible light, laser light. Alternatively, the present invention relates to a retroreflective article on which an image is formed by partially removing a specular reflection layer of a retroreflective element, which is useful in a reflection plate of infrared light reflection type sensors, and a method for manufacturing the same.

[0003] More specifically, it comprises a first layer comprising a substantially transparent layer having a flat first surface and a retroreflective element layer having a second surface from which the specular reflection layer is exposed. Using a retroreflective article consisting of a second layer, A. Step of placing a photoreactive resin layer on the specular reflection layer on the second surface B. Partially reacting the photoreactive resin by selective light irradiation Step C. Step of partially removing the non-reactive region of the photoreactive resin layer D. Retroreflective article having an image formed by the step of forming an image by partially removing the specular reflection layer, and a method for producing the same Regarding

[Prior art]

[0004] Conventionally, various methods have been proposed as a method for forming an image on a retroreflective article.

As a conventionally known method of forming an image, a method of forming an image by a printing method using a printing ink on the surface (first surface) or the inner surface of the surface protective layer has been generally used. The printing method includes U.S. Pat. Nos. 3,154,872 and 3,8.
01,183, 4,082,426 (JP-A-53-68596),
4,097,838 are disclosed. Here, the citation of this document is substituted for this concrete description.

[0006] Further, a method of directly placing an image on a retroreflective element is also known.

[0007] In Lytle's Tokukaihei No. 10-500230 retroreflective product and its manufacture, (a) supporting a layer of microspheres on a carrier; (b) the first portion of the layer of microspheres is behind it. A reflective metal layer selectively supported on the layer of the supported microspheres so that the second portion does not have such a reflective metal layer functionally coated onto the microsphere layer. (C) partially embedding the layer of microspheres on the first major surface of the binder layer; (d) leaving the layer of microspheres partially embedded on the first major surface of the binder layer. Removing the carrier from the layer of microspheres so that a retroreflective article having first and second segments is formed, wherein the first segment is functionally located behind the embedded portion of the microspheres. With a deposited evaporated reflective metal layer Is disclosed.

[0008] In Japanese Patent Laid-Open No. 4-229244 of Martin, an adhesive layer is partially formed on a metal adhesion layer formed on a retroreflective microprism surface, and a metal layer not protected by the adhesion layer is peeled off. Discloses a method of forming a retroreflective microprism sheet in which a metal layer is not partially installed. Further, it is described that it is desirable that the adhesive layer (protective coating material) partially installed is a pressure-sensitive adhesive that does not have a serious adverse effect in a solvent treatment step in a subsequent process. Furthermore, a printing method is described as a method of installation.

[0009] Further, in Japanese Patent Laid-Open No. 1-21004 of Martin, an adhesive layer is partially formed on a metal adhesion layer formed on a retroreflective microprism surface, and a metal layer not protected by the adhesion layer is drawn. A method of forming a retroreflective microprism sheet in which a metal layer is not partially installed by peeling, and a metal deposition is performed after partially installing a coating material on the retroreflective microprism surface, and then the partial A method of forming a retroreflective microprism sheet partially free of a metal layer by removing the selectively coated material is disclosed.

[0010] A method of removing the vapor deposition layer by laser is also commonly used.

[0011] US Pat. No. 4,200,8 by Galanos
No. 75 discloses a method in which an image is formed on an exposed lens type retroreflective sheet by a laser method in a predetermined pattern.

[Problems to be Solved by the Invention]

An object of the present invention relates to an image-formed retroreflective article and a method for manufacturing the same, and relates to a novel retroreflective article having an image formed by partial removal of a specular reflection layer and a method for manufacturing the same.

As a conventionally known method of forming an image, a method of forming an image by a printing method using a printing ink on the surface (first surface) or the inner surface of the surface protective layer has been generally used. However, in the method using such a printing ink, deterioration of the resin layer forming an image is easily promoted by the penetration of light or water from the outside, and it is difficult to obtain an image having excellent durability.

[0014] Furthermore, Martin Japanese Patent Laid-Open No. 4-229244 and Japanese Patent Laid-Open No.
As disclosed in 1-2311004, by partially forming an adhesive layer on the metal adhesion layer formed on the retroreflective microprism surface, and peeling off the metal layer not protected by the adhesion layer, In the method of forming the retroreflective microprism sheet in which the metal layer is not partially installed,
Since it is necessary to set the adhesive layer by a printing method or the like, the adhesive containing the solvent flows out along the grooves between the prisms, and it is difficult to form a clear image. further,
There is also a problem that the prism is deformed by the solvent and the retroreflective performance is deteriorated.

[0015] A method of removing the vapor deposition layer by laser is also commonly used. However, the method of forming an image by the laser method has a problem that the retroreflective performance is deteriorated because the minute glass spheres and prisms, which are reflective elements, are partially destroyed. Further, since the diameter of the laser beam that can be used is small, an image that can be formed is obtained as a collective image of minute points, so it is difficult to obtain a clear image, and it is difficult to form an image in a wide range.

[0016] It is an object of the present invention to provide a novel retroreflective article having an image formed by partial removal of a specular reflection layer and a method for producing the same, in order to improve the above-mentioned problems of the prior art. Is.

[Means for Solving the Problems]

The present invention comprises a first layer comprising a substantially transparent layer having a flat first surface and a retroreflective element layer having a second surface with an exposed specular reflection layer. Using a retroreflective article consisting of a second layer, A. Step of placing a photoreactive resin layer on the specular reflection layer on the second surface B. Partially reacting the photoreactive resin by selective light irradiation Step C. Step of partially removing a selected region of the photoreactive resin layer D. Retroreflective article having an image formed by the step of forming an image by partially removing the specular reflection layer, and a method for manufacturing the same .

The types of retroreflective articles that can be used in the present invention include a first layer comprising a substantially transparent layer having a flat first surface and a second layer having an exposed specular reflective layer. A retroreflective article including a second layer including a retroreflective element layer having a surface can be appropriately selected, and the retroreflective element layer includes an encapsulated lens type, a capsule lens type, and a specular reflection prism type. A retroreflective article composed of a retroreflective element selected from the group of retroreflective elements is preferred.

[0019] As an example of the encapsulation type retroreflective element, a fine glass-sphere type retroreflective element having a diameter of the retroreflective element constituting the retroreflective portion of 30 to 500 µm is preferable, and a surface protective layer having a smooth and transparent surface is used. Is covered. In a reflective element with a diameter of less than 30 μm, the divergence of light due to the diffraction effect becomes excessive and the retroreflective performance deteriorates, which is not preferable. In a reflective element with a diameter of more than 500 μm, the sheet thickness becomes excessive,
In addition, the sharpness of the formed image decreases, which is not preferable.

[0020] As an example of the capsule lens type retroreflective element,
The diameter of the retroreflective element that constitutes the retroreflective part is 30 to 500.
A micrometer-sized micro-glass type retroreflective element is preferable, and the plastic film forming the surface protective layer has a smooth and transparent surface. Similar to the encapsulated lens type retroreflective sheet, in a reflective element having a diameter of less than 30 μm, the divergence of light due to the diffraction effect becomes excessive and the retroreflective performance deteriorates, which is not preferable.
In a reflective element having a diameter of more than μm, the thickness of the sheet becomes excessive, and the sharpness of the image formed is reduced, which is not preferable.

[0021] An example of the specular reflection type prism element is a cube-corner type retroreflective element in which the height of the retroreflective element constituting the retroreflective portion is 50 to 500 μm, and the reflective surface of the element is a mirror surface made of a metal thin film. An example is a retroreflective element that has been treated to form a specular reflection layer. The height of the element
In a cube-corner reflective element of less than 50 μm, the divergence of light due to the diffraction effect becomes excessive and the retroreflective performance deteriorates, which is not preferable, and in a cube-corner reflective element having a height of more than 500 μm, the sheet thickness becomes excessive, and
It is not preferable because the sharpness of the formed image is lowered.

As a preferred embodiment of the specular reflection type prism element, a bottom surface formed by intersecting V-shaped grooves having a substantially symmetrical cross section with each other has a triangular shape, and three substantially right angles are provided. A pair of specular-reflecting triangular-pyramidal prism elements separated by intersecting side surfaces are preferable.

[0023] Further, the optical axis of the specular reflection type prism element can be tilted in order to improve the incident angle characteristic at the time of retroreflection. The angle of inclination is 0.5 to 12 degrees, preferably 0.6 to 10 degrees, and more preferably 0.7 to 1.5.
The tilting direction may be either a direction in which the optical axes of a pair of mirror-reflecting triangular-pyramidal prism type elements facing each other are close to each other or a direction in which they are away from each other.

[0024] As an example of a preferable specular reflection type triangular pyramid prism type element, triangular pyramid type cube corner retroreflective elements protruding on one common bottom surface (XX-X ') are mutually formed on the bottom surface (XX-X'). ) One bottom side is shared, and the bottom side (X-
X ') is a common plane that includes a number of the bases (x, x, ...) Shared by the triangular pyramidal reflection elements, and two triangular pyramidal reflection elements that are relatively facing each other are Bottom (XX ')
Faced so as to be symmetric with respect to a plane (Y-Y ', Y-Y', ....) perpendicular to the bottom surface including the shared base (x, x, ...) Above. The triangular-pyramidal reflective elements are formed of a pair of elements having substantially the same shape, and the triangular pyramidal reflection elements have substantially the same pentagonal inclined surface (c1) having the shared base (x, x, ...) As one side. , C2) and the upper two sides of the c1 plane or the c2 plane starting from the apex (H) of the triangular pyramidal reflective element as one side, and share one ridgeline of the triangular pyramidal reflective element. , Substantially the same quadrangular inclined surface (a1) that intersects at right angles with the c1 surface or the c2 surface having one side thereof.
Surface, b1 surface; a2 surface, b2 surface), and the base (x, x) of the pentagonal inclined surface (c1, c2) of the triangular-pyramidal reflective element from the vertex (H) of the triangular-pyramidal reflective element. , ..) to the bottom surface (XX ′) from the apex (H) of the triangular-pyramidal reflective element to another inclined surface (H) of the triangular-pyramidal reflective element. a1 plane, b1 plane; a2 plane, a2 plane, and a substantially horizontal plane (virtual plane Z-) including the bases (z, w) of
A specular reflection type prism element characterized by being substantially larger than the height (h ') up to Z') can be mentioned. Regarding a triangular-pyramidal cube-corner retroreflective sheet including such an element, International Patent Publication WO 01/5
No. 7560A1, which is incorporated herein by reference to this specific description.

[0025] As a more preferable example of the specular reflection type prism type element, the triangular pyramid type cube corner retroreflective element has three cross-sectionally substantially symmetrical V-shaped grooves intersecting with each other to form three Sides (a
1st, b1st, c1st; a2nd, b2nd, c2nd;…),
A pair of triangular-pyramidal cube-corner retroreflective elements separated by a pair of triangular-pyramids are arranged in a close-packed manner so as to project to one side on a common bottom surface (SS). In the type retroreflective element, the side faces (c1 face, c2 face) facing each other share one base (x) and form a pair, and the bottom face (S-S ') is the pair of triangular pyramids. One side (a1 surface, a2 surface) of the retroreflective element has a base (z,
z) and the bottom of the other side surface (b1 surface, b2 surface) (y,
y) and a pair of triangular-pyramidal retroreflective elements that share a base (x) and have a common side surface (c1 surface, c2 surface) different from each other. In addition, a specular reflection type prism element having different heights from the plane (S-S ') to the apex can be mentioned. A triangular-pyramidal cube-corner retroreflective sheet including such an element is described in Japanese Patent Application Laid-Open No. 2001-264525, and here, the citation of this document is used instead of this specific description.

[0026] As the material forming the specular reflection layer of the retroreflective element, for example, metal thin films such as aluminum, silver, nickel, copper, and gold can be installed individually or in combination. As a method of installing the specular reflection layer,
A vapor deposition method, a sputtering method, an electroplating method, a chemical plating method, or a metal-tone resin layer installation method using an ink or paint having a metallic luster appearance can be appropriately adopted. Moreover, the thickness of the specular reflection layer to be installed is 0.2 to 2 μm.
The thickness may be, for example, m, preferably 0.5 to 1.5 μm.

[0027] The above specular reflection layer is particularly preferably an aluminum specular reflection layer. The continuous vapor deposition processing apparatus for the aluminum specular reflection layer includes a vacuum container capable of maintaining a vacuum degree of about 7 to 9 × 10 −4 mmHg, a substrate sheet installed therein, and a surface protective layer laminated on the light incident side surface thereof. An unwinding device for unwinding a prismatic raw sheet made of, a winding device for winding up a vapor-deposited prismatic raw sheet, and a heating device between them, which is capable of melting aluminum with an electric heater in a graphite crucible. Has become Pure aluminum pellets having a purity of 99.99% by weight or more are put into the graphite crucible.
A specular reflection layer having a thickness of, for example, 0.2 to 2 μm is formed on the surface of the retroreflective element by the molten and vaporized aluminum atoms under the conditions of 50 to 360 V, current of 115 to 120 A, and treatment speed of 30 to 70 m / min. It can be vapor-deposited.

In the present invention, the first layer including a substantially transparent layer having a flat first surface has a diameter of a retroreflective element forming a retroreflective portion in the case of an encapsulation type retroreflective element.
It is in direct contact with a micro-glass type retroreflective element of 30 to 500 μm, and in the case of a capsule lens type retroreflective element, it is separated by an air layer through a partially sealed encapsulation structure. Also,
In the case of the specular reflection type prism type element, it may be formed as an independent layer so as to be in close contact with the reflection element layer, or may be formed as the same layer as the resin layer forming the prism type element. .

The thickness of the first layer in the present invention can be appropriately selected within a range that does not impair the visibility of the formed image which is the object of the present invention, but a preferable thickness is any type of element. In the above, the thickness is, for example, 10 to 2000 μm, more preferably 20 to 100 μm.

Further, the resin that can be used for the first layer is
It is desirable to use one having excellent transparency in order to improve retroreflective performance and image visibility. First used in the present invention
As for the transparency of the layer, in the case of a colorless resin which is not colored, the light transmittance is 50 to 98%, preferably 60.
˜97% can be used.

Various transparent plastic materials can be used as the resin that can be used in the first layer including the substantially transparent layer having the flat first surface in the present invention. Polycarbonate resin, vinyl chloride resin, (meth) acrylic resin, epoxy resin, polystyrene resin, polyester resin, fluororesin, polyolefin resin such as polyethylene resin and polypropylene resin,
Cellulosic resins and polyurethane resins may be used alone or in combination.

[0032] Further, for the purpose of improving weather resistance, an ultraviolet absorber, a light stabilizer, an antioxidant and the like can be used alone or in combination. Furthermore, various organic pigments, inorganic pigments, fluorescent pigments, dyes, fluorescent dyes and the like can be contained as colorants.

[0033] Next, in the present invention, a first layer comprising a substantially transparent layer having a flat first surface and a retroreflective element layer having a second surface from which the specular reflection layer is exposed are provided. Using a retroreflective article consisting of a second layer containing A. Step of placing a photoreactive resin layer on the specular reflection layer of the second surface B. Part of the photoreactive resin by selective light irradiation The step of forming an image by the step C. the step of partially removing the selected region of the photoreactive resin layer and the step of forming the image by the partial removal of the specular reflection layer will be described below.

[0034] The step of installing the photoreactive resin layer on the specular reflection layer of the second surface which is the first step includes continuous or sheet-like screen printing on the second surface where the specular reflection layer is exposed. Direct coating methods such as coating method, gravure printing method, various coating methods, and spraying method can be adopted.

[0035] At this time, the region where the photoreactive resin is installed can be limited in advance, and the photoreactive resin can be partially installed by a printing method or a coating method.

Alternatively, a method in which a sheet-shaped photoreactive resin is laminated on the specular reflection layer by applying pressure with a heat roll may be employed.

In the present invention, the thickness of the minimum portion of the layer forming the photoreactive resin layer provided on the specular reflection layer on the second surface is 1
It is preferably 0 to 200 μm. More preferably, the thickness is 30 to 100 μm.

[0038] When the thickness is less than 10 µm, the agent for removing the specular reflection layer penetrates through the photoreactive resin layer and reacts with the specular reflection layer when partially removing the specular reflection layer. On the other hand, when the thickness exceeds 200 μm, light scattering is likely to occur inside the photoreactive resin layer during selective photoreaction, which makes it difficult to form a clear image, which is not preferable. Furthermore, when the specular reflection layer is partially removed, it becomes difficult for a chemical agent for removing the specular reflection layer to enter, which makes it difficult to remove the specular reflection layer, and again it is difficult to form a clear image, which is preferable. Absent. In addition, the thickness of the photoreactive resin layer becomes excessively large, which makes it difficult to obtain a flexible sheet product, which is not preferable.

[0039] In the present invention, the photoreactive resin layer provided on the specular reflection layer on the second surface may be appropriately selected from photopolymerizable, photocondensed, photocrosslinkable and photodegradable resins. These resins undergo a change in physical properties such as a change in solubility, a change in phase from a liquid to a solid, and a change in adhesiveness upon irradiation with light, and thus a partial image can be formed.

[0040] As a first example of the photoreactive resin that can be used in the present invention, a so-called acrylic prepolymer used as a UV curable ink is used as a vehicle, and a reactive monomer and a photopolymerization initiator are added to the vehicle. A UV-curable resin containing additives and auxiliaries can be used. As the vehicle, acrylic polymers such as polyester acrylate, epoxy acrylate, and urethane acrylate having a weight molecular weight of about 1,000 to 5,000, and modified alkyd resins having an acryloyl group introduced can be used.

[0041] Examples of the polyester acrylate include a prepolymer in which an acryloyl group is introduced into both ends of a polyester resin obtained from adipic acid and 1,6-hexanediol. As an example of the epoxy acrylate, a prepolymer obtained by reacting glycidyl groups at both ends of an epoxy resin with acrylic acid can be used. Examples of polyurethane acrylate include a prepolymer obtained by reacting both ends of a polyester resin obtained from adipic acid and 1,6-hexanediol with tolylene diisocyanate resin, and subsequently with 2-hydroxyethyl acrylate. Can be used.

[0042] Examples of reactive monomers that can be used include polyfunctional acrylates such as diethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, and pentaerythritol triacrylate. A class can be used.

As the photopolymerization initiator that can be used in the above photoreactive resin, those that absorb UV light and efficiently generate radicals effective for the polymerization reaction are preferable. For example, various benzoin derivatives, 2,2-dimethoxy-2
UV in the presence of phenylacetophenone, hydrogen donor
Aromatic carbonyl compounds such as benzophenone and thioxanthone that generate a radical by causing a hydrogen abstraction reaction by irradiation with light can be used. Further, the addition of amines can make the generation of radicals efficient.

[0044] Further, various pigments, thixotropy imparting agents,
It is also possible to add a thermal polymerization inhibitor, waxes and the like.

[0045] These UV-curable resins can be printed by various printing methods,
For example, it can be installed on the specular reflection layer by a screen printing method, a gravure printing method, and various coating methods.

[0046] As a second example of the photoreactive resin that can be used in the present invention, a so-called negative-type resin obtained by condensing p-diazophenylamine with paraformaldehyde to form an aromatic sulfonate. A diazo resin photosensitive material can be used.

The above-mentioned aromatic sulfonate is preferably used by mixing with a binder polymer such as 2-ethylhydroxymethacrylate-methylmethacrylate copolymer resin. In such a photoreactive resin, the diazo group can be decomposed and insolubilized by light irradiation.

A third example of the photoreactive resin that can be used in the present invention is composed of an acrylic polymer binder having an aryl group introduced in its side chain, a polyfunctional acrylate monomer, and a photopolymerization initiator. Photopolymerizable photopolymers that are present can be used.

[0049] As an example of an acrylic monomer that can be used for an acrylic polymer binder in which an aryl group is introduced into a side chain, various acrylic acids, methacrylic acid, acrylic acid esters, methacrylic acid esters, and aryl methacrylate are used. You can

[0050] Examples of polyfunctional acrylate monomers that can be used in the present invention include diethylene glycol diacrylate, neopentyl glycol diacrylate,
1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, etc. can be used.

[0051] As examples of the photopolymerization initiator that can be used in the present invention, various organic peroxides, diphenyliodonium salts, N-phenylglycine, trichloromethyltriazine, iron arene complexes, and the like can be used. Further, it is preferably used in combination with a photosensitizer such as a thiopyrylium salt, a ketocoumarin dye or a thioxanthene dye.

[0052] As an example of the third photoreactive resin that can be used in the present invention, generally, a photoresist material is used to form an etching-resistant thin film by light irradiation and a partial etching treatment of metal is performed. The photoreactive resin for resist used for that purpose can be mentioned.

[0053] Specific examples of the photoreactive resin for a resist include a photosensitizer obtained by esterifying o-naphthoquinonediazosulfonic acid into a novolac resin, 2,3,4-trihydroxybenzophenone or tetrahydroxybenzophenone, and cresol. A positive type photoresist resin mixed with a type novolak resin may be used.

[0054] The o-naphthoquinonediazide compound is decomposed by light irradiation and is converted to an alkali-soluble 3-indenecarboxylic acid type compound via a carbene and ketene structure.
Before the light irradiation, the o-naphthoquinonediazidosulfonyl group acts as a dissolution accelerator for the novolak resin, but after the photodecomposition acts as a dissolution accelerator, so that the solubility of the light-irradiated portion in the alkaline aqueous solution increases. As a result, only the exposed portion is dissolved and removed to form a positive image.

The above-mentioned type of positive photoresist resin is excellent in etching suitability because it has excellent resolution and alkali resistance in the ultraviolet region to the visible light region, and has a retroreflective property in which the image of the present invention is formed. Preferred for forming sexual articles.

[0056] Examples of water-soluble photoresist materials include materials obtained by adding 2 to 9% of dichromate to water-soluble polymers such as casein, glue, and polyvinyl alcohol.

A cinnamic acid-based resist material can also be used. This resist material is made by reacting polyvinyl alcohol with cinnamic acid chloride having a photodimerization type photosensitive group, and produces an insoluble resin by irradiating ultraviolet rays of 230 to 450 nm. Furthermore, it is preferable to add 5-nitroacenaphthene, 1,2-benzanthraquinone or the like as a photosensitizer.

Further, a rubber-based resist material can also be used. This resist material is, for example, a rubber such as natural rubber, cyclized polyisoprene, or polybutadiene to which a bisazide compound is added as a photosensitizer. Upon irradiation with light, the azido group decomposes to become a reactive nitrene intermediate, which reacts with rubber and becomes insoluble.

[0059] Examples of bisazide compounds used for these rubber-based resist materials include 2,6-di- (4'-azidobenzylidene) cyclohexane and 2,6-di- (4'-azidobenzylidene) -4-methylcyclohexane. Can be raised.

Since these rubber-based resist materials are excellent in chemical resistance, durability and resolution, they are preferable for forming the image-formed retroreflective article of the present invention.

[0061] As an example of the fourth photoreactive resin that can be used in the present invention, a sheet-shaped photoreactive resin that is generally sold as a product for use as a dry film photoresist for forming printed wiring of electronic devices and the like is used. Resin. Usually, it is sold in the form of sandwiching a protective film on both sides. While peeling off the protective film, it is laminated on the specular reflection layer of the retroreflective article used in the present invention by thermocompression bonding.

The materials used for the dry film photoresist are a binder polymer, a polyfunctional monomer, a polymerization initiator,
It is composed of a thermal polymerization inhibitor, adhesion promoter and plasticizer. An example of the binder polymer is a (meth) acrylate resin whose main component is methyl methacrylate,
Alternatively, styrene, acrylonitrile and a (meth) acrylic acid copolymer can be used. A benzoin derivative, 2,2-dimethoxy-2-phenylacetophenone, or the like can be used as the polymerization initiator.

This dry film photoresist becomes insoluble in an alkali developing solution upon irradiation with ultraviolet rays. The thickness of the sheet that can be used is 10 to 100 μm, and preferably 10 to 50 μm. Such a sheet-shaped photoreactive resin is excellent in resolution because it can form a uniform film, and is particularly preferable for forming the image-formed retroreflective article of the present invention. Further, since a solvent is not used, the retroreflective element is not deformed by the solvent through the mirror surface layer of the retroreflective article, which is particularly preferable in the case of the prism type retroreflective article.

[0064] When laminating the dry film photoresist and the specular reflection layer of the retroreflective article by thermocompression bonding, it is necessary to take care not to deform the element due to heat. For example, in the case of a specular reflection type prism type retroreflective article using polycarbonate resin for the prism layer, for example, a heating temperature of 50 to 90 degrees and a pressing force of 2 kg.
The condition of / cm2 can be illustrated. When the heating temperature is low, the adhesion with the specular reflection layer is insufficient and the infiltration of the developer occurs, which is not preferable, and when the heating temperature is too high, the retroreflection performance is deteriorated due to the deformation of the prism element, which is not preferable. The pressure and pressure should be appropriately selected depending on the heat deformation temperature of the resin and resist film used in the retroreflective article.

[0065] The photoreactive resin installed as described above is
By selectively irradiating light as the second step, photopolymerization, photocondensation, photocrosslinking and photolysis are performed, and the photoreactive resin layer can be removed in a pattern corresponding to a desired image.

[0066] As a method of selectively irradiating light, a method of using a light-shielding mask in which an image pattern is printed or cut out, a method of continuously forming an image using a laser beam, or the like can be used. The laser beam used may be a g-line having a wavelength of 436 nm which is a visible light laser, and the i-line having a wavelength of 365 nm and an excimer laser line having a wavelength of 248 nm generated by KrF may be used as an ultraviolet laser.

In the present invention, the light used for the reaction of the photoreactive resin is not particularly limited to visible light as long as photopolymerization, photocondensation, photocrosslinking and photodecomposition can be performed,
Electromagnetic waves such as ultraviolet rays, infrared rays, far infrared rays and X-rays are also included.

The shape of the image to be generated is not particularly limited, and information patterns such as characters and logos are provided, or the specular reflection layer is partially removed to reduce or eliminate retroreflectivity at night. Alternatively, it is possible to set patterns and information that can be distinguished by the change of the hue or reflected light hue in the daytime.

[0069] Further, in the retroreflective article in which the non-contact type IC communication device with the thin layer antenna is laminated, the specular reflection layer is partially removed, and the information communication is installed on the lower surface of the reflection element layer. It is also possible to improve the receiving sensitivity of the thin layer antenna.

[0070] The photoreactive resin that has been selectively photoreacted as described above uses various solvents and the like in the third step,
In the case of photopolymerizable, photocondensable, and negative type photocrosslinkable resins, the non-reacted part that was not irradiated with light, and in the case of positive type photodegradable resin, the decomposed reaction part that was irradiated with light Are partially removed.

[0071] After the photoreaction, the portion that remains as the soluble portion is removed with various solvents, but the solvent that can be used for removal is appropriately selected according to the solubility of the photoreactive resin used. However, for example, in the case of a water-based emulsion type resin, water, an acid aqueous solution, an alkaline aqueous solution can be used, and various organic solvents may be used.

[0072] Then, in the fourth step, the retroreflective article in which the photoreactive resin has been partially removed and the specular reflection layer is exposed is exposed to specular reflection using various acids, alkaline aqueous solutions or organic acids. The layer is partially removed.

[0073] When the removal solvent used in the removal step of the photoreactive resin described above is an alkaline aqueous solution or the like, this removal step of the specular reflection layer may be successively performed as a series of steps.

[0074] Further, the alkali and acid used for removing the photoreactive resin and the specular reflection layer are washed with a neutralizing agent and water so that the residual portion of the adjacent specular reflection layer is not damaged. Preferably.

[0075] The remaining photoreactive resin layer may or may not be left as it is. To remove the photoreactive resin layer,
It is possible to use a method such as removing using a stronger solvent or the like, or laminating an adhesive sheet and then peeling it off together with the photoreactive resin layer.

[0076] In the present invention, it is also possible to dispose a colorant in the region where the specular reflection layer is removed to color the image. As a method of coloring, a method of applying a colored resin containing various pigments or dyes can be adopted. Also, by installing a resin with a metallic appearance in which a metal foil or pearl pigment is contained in the colored resin, or by installing a light-transmitting colored resin layer and then installing a specular reflection layer again, It is also possible to provide retroreflective performance.

The image-formed retroreflective article formed as described above may be laminated with an adhesive or a pressure-sensitive adhesive for the purpose of laminating on aluminum, iron, plastic, glass, paper, wood board, or the like. As a method for laminating, a method may be employed in which an adhesive liner obtained by laminating an adhesive and a release liner and a retroreflective article are pressed by a pressing roll while applying heat as necessary.

[0078] As the adhesive that can be used in the retroreflective sheeting of the present invention, a pressure-sensitive adhesive, a heat-sensitive adhesive, a cross-linking adhesive, or the like can be appropriately selected. As the pressure-sensitive adhesive, butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, nonyl acrylate, etc. Polyacrylate ester adhesive obtained by copolymerizing acrylic acid ester with acrylic acid, vinyl acetate, etc. A rubber-based pressure-sensitive adhesive or the like can be used. As the heat-sensitive adhesive, acrylic resin, polyester resin, epoxy resin or the like can be used.

[0079] Next, the present invention will be described in more detail with reference to the drawings.

[0080] Fig. 1 is a cross-sectional view illustrating an encapsulated retroreflective article based on a conventional technique. The printing layer 3 is placed by a printing method to form an image. The specular reflection layer 7 forms a retroreflective element provided on the minute glass bulb 5 via the focal layer 6, and is laminated on the flat and transparent surface layer 2 via the fixing layer. Further, an adhesive layer 8 and a release material layer 9 are provided on the specular reflection layer, and are designed to retroreflect the incident light 1 in the direction in which the light is incident.

[0081] Next, a method for forming an image-formed encapsulated retroreflective article according to the present invention will be described in detail with reference to Figs.

FIG. 2 is a cross-sectional view of an image-free encapsulated retroreflective article formed by the prior art. The first surface has a flat and transparent surface layer 2 and the second surface has a specular reflection layer 7
The retroreflective element installed on the minute glass bulb 5 is exposed through the focal layer 6.

In FIG. 3, the photoreactive resin 10 is laminated on the exposed specular reflection layer 7.

[0084] FIG. 4 is a diagram illustrating a step of setting a light shielding mask 11 on the laminated photoreactive resin 10 and irradiating light to perform a selective photoreaction. Figure 4 shows the selective photoreaction.
It can also be achieved by selectively irradiating light by a laser beam method without using a mask as shown in FIG.

[0085] FIG. 5 shows that the photoreactive portion formed by the selective photoreaction is not exposed to light in the case of a photopolymerizable or photocondensable negative-type photocrosslinkable resin using various solvents. It is a figure explaining the process which partially removes the non-reacting part, and in the case of a positive type photodegradable resin, the decomposition reaction part irradiated with light. The photoreactive resin layer 10 has the image forming portion removed, and the specular reflection layer is exposed.

[0086] Fig. 6 shows a retroreflective article in which the specular reflection layer 7 exposed in the step of Fig. 5 is removed by a removing solvent, and an image is formed in that portion.

[0087] Fig. 7 is a diagram in which an adhesive layer 8 is provided for attaching the image-formed retroreflective article to various base materials.

[0088] FIG. 8 is a cross-sectional view illustrating a specular reflection type prism retroreflective article on which an image 3 is formed by a printing method based on a conventional technique. The first surface has a transparent and flat surface layer 2, a prismatic layer 7 is provided on the reflecting surface of the prism element in the prism layer 12, and an adhesive layer 8 and a release material layer 9 are further provided.

[0089] Next, a method for forming an image-formed specular reflection prism type retroreflective article according to the present invention will be described in detail with reference to Figs. 9 to 12.

[0090] FIG. 9 illustrates a process of installing a light shielding mask 11 on a prism type retroreflective article in which the photoreactive resin 10 is installed on the mirror surface layer 7 and irradiating light to perform a selective photoreaction. It is a figure. The selective photoreaction can also be achieved by selectively irradiating light by a laser beam method without using a mask as shown in FIG.

[0091] FIG. 10 shows that the photoreactive portion formed by the selective photoreaction is not irradiated with light in the case of a photopolymerizable or photocondensable negative-type photocrosslinkable resin using various solvents. It is a figure explaining the process which partially removes the non-reacting part, and in the case of a positive type photodegradable resin, the decomposition reaction part irradiated with light. The photoreactive resin layer 10 has the image forming portion removed, and the specular reflection layer is exposed.

[0092] FIG. 11 shows the specular reflection layer 7 exposed in the step of FIG.
Is a retroreflective article in which an image is formed by removing the solvent with a removing solvent.

FIG. 12 shows an adhesive layer 8 for attaching the image-formed retroreflective article in FIG. 11 to various base materials.
It is the figure which installed.

【The invention's effect】

The image formed by the method according to the present invention is directly formed on the reflective element, and the image itself is essentially easily decomposed by infiltration of a coloring agent such as a printing ink or a binder resin by light or water. Since no component is required, an image with excellent weather resistance and durability can be formed.

[0095] In the method of forming an image by a printing method using a printing ink on the surface (first surface) or the inner surface of the surface protective layer, which is a conventionally known method of forming an image, the resin layer does not emit light from the outside. Deterioration is likely to be promoted by the entry of water and water, making it difficult to obtain images with excellent durability. However, in the method of forming an image by partially removing the specular reflection layer according to the present invention, the problem of deterioration of the printing ink does not occur, so an image having excellent durability is formed.

[0096] Further, an adhesive layer is partially formed on the metal adhesion layer formed on the retroreflective microprism surface as disclosed in Martin JP-A-4-229244 and JP-A-1-231004. , In the method of forming a retroreflective microprism sheet in which a metal layer is not partially provided by peeling off a metal layer which is not protected by an adhesive layer,
Since it is necessary to install the adhesive layer by a printing method or the like, the adhesive containing the solvent flows out along the grooves between the prisms, and a clear image cannot be formed. further,
The problem that the prism is deformed by the solvent and the retroreflective performance is deteriorated is apt to occur. However, in the method of forming an image by partially removing the specular reflection layer according to the present invention, a clear image can be formed without causing the above problems.

Further, the method of forming an image by the laser method has a problem that the retroreflection performance is deteriorated because the minute glass spheres and prisms that are the reflection elements are partially destroyed. Furthermore, since the diameter of the laser beam that can be used is small, the image that can be formed is obtained as a collective image of minute points, so it is difficult to obtain a clear image, and it is difficult to form an image in a wide range. In the method of forming an image by partially removing the specular reflection layer according to the present invention, it is possible to form a clear and wide-ranging image in which the above-mentioned problems do not easily occur.

[0098] Hereinafter, the present invention will be described in more detail with reference to Examples.

【Example】

<Example 1> Specular reflection type prism type retroreflective sheet manufactured by Nippon Carbide Industry Co., Ltd., the specular reflection layer is exposed before the adhesive layer of Nikkalite Crystal Grade # 96002 type is installed. A retroreflective sheet having two surfaces was used as a starting material (starting material 1) to prepare a retroreflective sheet having an image formed by the following steps. The manufacturing process will be described in detail below.

[0100] The starting material 1 used in this example has a structure in which the printing layer 3, the pressure-sensitive adhesive layer 8 and the release material layer 9 of the conventionally known specular reflection type prism retroreflective sheet shown in FIG. 8 are not provided, The first surface is a flat and transparent surface layer 2 made of acrylic resin having a thickness of 50 μm, and the reflecting surface of the prism element in the prism layer 12 made of polycarbonate has a thickness of 0.8.
A mirror layer 7 made of aluminum and having a thickness of 7 μm is installed and exposed by a vacuum deposition method.

As the photoreactive resin, a dry film photoresist type alkali development type photosensitive film “Photec” H2300 manufactured by Hitachi Chemical Co., Ltd. was used. The dry film resist had a film thickness of 48 μm, and both surfaces were protected by a light-transmitting carrier film and a protective film.

[0102] Using a pair of thermocompression-bonding rolls, the starting raw material 1 was laminated while peeling off the protective film of the dry film resist while leaving no air on the exposed surface of the specular reflection layer, Process product 1 in which the raw material 1, the dry film resist and the carrier film are laminated 1-
Got 1.

[0103] A thickness of 75 μm in which a character image was printed with black ink on the surface of the process film 1-1 on the carrier film side.
The mask film made of polyester resin of No.1 is installed, and the exposure process is performed for 20 seconds using a high-pressure mercury lamp type ultraviolet irradiation device (manufactured by Ushio Inc.) with a lamp input of 80 w / cm, and photoreactivity is achieved by selective light irradiation. Process product 1-2 for partially reacting the resin was obtained. The mask film used was printed with alphabetic characters "ABC" with a character size of 11 points and a character size of Century for the purpose of evaluation of visibility.

[0104] Then, after removing the carrier film of the above-mentioned process product 1-2, an aqueous solution of sodium hydroxide having a concentration of 3% by weight was used as a developer, and the photoreactive resin in the unreacted portion was heated at a temperature of 40 ° C. After removing, the product was washed with water to prepare process products 1-3.

[0105] In the process product 1-3, the specular reflection layer was partially removed using a nitric acid aqueous solution having a concentration of 10% by weight, and then the product was washed with water and dried to obtain a process product 1-4. It was The conditions for the nitric acid treatment were a temperature of 40 degrees and an etching time of 15 seconds.

An acrylic resin adhesive (Nisset KP1818 manufactured by Nippon Carbide Industries Co., Ltd.) having a thickness of 50 μm and a thickness of 8 on the second surface on the image-formed side of Process Product 1-4 described above.
An image-formed retroreflective sheet (Prototype 1) was prepared by laminating 0 μm polypropylene release material manufactured by Okura Industry Co., Ltd.

<Example 2> Instead of the starting material 1 used in Example 1, before installing an adhesive lens layer of an enclosed lens type retroreflective sheet ELG type manufactured by Nippon Carbide Industry Co., Ltd.,
Example 1 except that a starting material (starting material 2) was used as the retroreflective sheet having the second surface with the specular reflection layer exposed.
An image-formed retroreflective sheet (Prototype 2) was prepared in the same manner as in (1).

[0108] The starting material 2 used in Example 2 has a structure in which the printing layer 3, the adhesive layer 8 and the release material layer 9 of the conventionally known enclosed lens type retroreflective sheet shown in FIG. 1 are not provided. As shown in FIG. 2, the first surface is flat and has a transparent thickness of 35 μ.
A surface layer 2 made of polyester resin having a thickness of m and a mirror surface layer 7 made of aluminum having a thickness of 1 μm are provided on the minute glass bulb 5 by a vacuum deposition method and exposed.

<Example 3> The starting material 2 used in Example 2 was used.
And to create the process product 2-1 described in Example 2.
Replaced the dry film resist film
Positive type g-line resist resin OFPR manufactured by Kaka Kogyo Co., Ltd.
800 is used to expose the specular reflection layer by screen printing
The entire second surface is laminated and dried to a thickness of 4
0 g / m ^TwoExample except that the photoreactive resin layer of
A retroreflective sheet with an image formed in the same way as in 2 (prototype
3) was obtained.

[0110] It is believed that the resist resin used in Example 3 has a composition using a novolak resin containing a naphthoquinonediazide (NQD) compound as a dissolution inhibitor as a binder. Ultraviolet light used for exposure has a wavelength of 436n
m of ultraviolet light was used. Further, an aqueous solution of sodium hydroxide having a concentration of 3% by weight was used as the exposure liquid, the unreacted portion of the resist resin was removed under the condition of a temperature of 40 ° C., and then washed with water to prepare a process product 3-3. went.

<Example 4> [0111] A part where the specular reflection layer of Process Product 1-4, which was created in Example 1 and was partially washed with water and then washed with water, was exposed. A red resin layer was placed on the entire surface of the second surface including the second screen ink so that the color of the image when viewed from the first surface was red.

[0112] After that, an acrylic resin adhesive having a thickness of 50 µm and a polypropylene release material having a thickness of 80 µm were laminated on the second surface on which the image was formed, and the image-formed retroreflective sheet. (Prototype 4) was created.

<Comparative Example> As a comparative product, instead of the starting material 1 used in Example 1, a retroreflective sheet having a printed image formed on a sealed lens type retroreflective sheet ELG type manufactured by Nippon Carbide Industry Co., Ltd. is used. I was there. In the retroreflective sheet used in the comparative example, the red printing layer 3 is provided by the gravure printing method on the conventionally known enclosed lens type retroreflective sheet shown in FIG. As shown in FIG. 2, the first surface is a flat and transparent surface layer 2 made of polyester resin having a thickness of 35 μm, and the minute glass bulb 5 has a mirror surface layer 7 made of aluminum having a thickness of 1 μm formed by a vacuum deposition method. It has been installed and exposed.

<Measurement method 1> Visibility test The prototype on which the character image "ABC" is formed is placed horizontally, and the light of the fluorescent lamp is irradiated from directly above the height of 1 m, and the distance is observed at an angle of 45 degrees. The visibility of the image formed under the condition of 45 cm was visually judged and ranked as follows. A: The presence of the image "ABC" can be clearly confirmed. B: Presence of image "ABC" can be confirmed. C: The presence of the image “ABC” can be confirmed slightly. D: Presence of image "ABC" cannot be confirmed.

<Measurement method 2> Visibility after weather resistance test As a weather resistance tester, CXW-B-812501500 manufactured by Atlas Electric Device Co. was used, and the exposure time was set to 3000 hours, except that JIS Z-9117 was used.
A weather resistance test was conducted according to the above. The visibility of the image after the accelerated weather resistance test was evaluated based on the visibility test method specified in Measurement Method 1.

<Measurement Method 3> Measurement of Retroreflective Performance Before Weather Resistance As a retroreflective performance measuring instrument, “Model 920” manufactured by Advanced Retro Technology Co., Ltd. is used, and before the accelerated weather resistance test defined in Measurement Method 2. The retroreflective performance of a 100 mm × 100 mm prototype is measured at appropriate 5 points according to JIS Z-9117 with an observation angle of 0.2 ° and an incident angle of 5 °, and the average value is used to measure the retroreflection of the retroreflective sheet. The performance.

<Measurement method 4> Measurement of retroreflective performance after weather resistance As in measurement method 3, a retroreflective performance measuring instrument “Model 920” manufactured by Advanced Retro Technology, Inc. was used, and 100 mm after accelerated weather resistance test. According to JIS Z-9117, the retroreflection performance of a × 100 mm prototype was measured at appropriate 5 points with an observation angle of 0.2 ° and an incident angle of 5 °, and the average value was used to evaluate the accelerated weather resistance of the retroreflective sheet. The later retroreflective performance.

[0118] A table in which the prototypes described in the above examples are compared by the above measurement method is shown below.

[0119]

[Table 1]

[0120] The prototype 1 to which the image is formed according to the description of the present invention
No. 4 exhibited excellent visibility and durability.

[Brief description of drawings]

FIG. 1 Encapsulated retroreflector retroreflective article according to prior art

FIG. 2 is a diagram illustrating a process of the encapsulated retroreflective article of the present invention.

FIG. 3 is a diagram illustrating a process of the encapsulated retroreflective article of the present invention.

FIG. 4 is a diagram illustrating a process of the encapsulated retroreflective article of the present invention.

FIG. 5 is a diagram illustrating a process of the encapsulated retroreflective article retroreflective article of the present invention.

FIG. 6 is a diagram illustrating a process of an encapsulated retroreflective article retroreflective article of the present invention.

FIG. 7 is a diagram illustrating a process of the encapsulated retroreflective article retroreflective article of the present invention.

FIG. 8 is a conventional specular prism type retroreflective article retroreflective article.

FIG. 9 is a diagram illustrating a process of a prism type retroreflective article retroreflective article of the present invention.

FIG. 10 is a diagram illustrating a process of a prism-type retroreflector retroreflective article of the present invention.

FIG. 11 is a diagram illustrating a process of a prism type retroreflective article retroreflective article of the present invention.

FIG. 12 is a diagram illustrating a process of the prism type retroreflective article of the present invention.

[Explanation of symbols]

1 incident light 2 surface layer 3 printing layers (image) 4 fixed layer 5 Micro glass bulb 6 Focus layer 7 Specular reflection layer 8 Adhesive layer 9 Release material layer 10 Photoreactive resin layer 11 Light-shielding mask 12 Prism layer

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H042 AA02 BA12 BA15 DA17 EA02                       EA07 EA14 EA16 EA20 EA21                 4F100 AB10 AK01C AK07 AK25                       AK41 AK45 AR00C BA03                       BA07 BA10A BA10C EJ19                       EJ192 EJ42 EJ422 EJ54                       EJ542 GB32 GB72 GB90                       JN01A JN06B

Claims (13)

[Claims] 1. A first layer comprising a substantially transparent layer having a flat first surface and a second layer comprising a retroreflective element layer having a second surface from which a specular reflection layer is exposed. Using a retroreflective article composed of a layer and A. a step of installing a photoreactive resin layer on the specular reflection layer of the second surface B. a step of partially reacting the photoreactive resin by selective light irradiation C. Step of partially removing selected areas of the photoreactive resin layer D. Retroreflective article on which an image is formed by the step of forming an image by partially removing the specular reflection layer. 2. A retroreflective element layer comprising a retroreflective element selected from the group consisting of an encapsulated lens type, a capsule lens type, and a specular reflective prism type retroreflective element.
A retroreflective article on which the image according to item 1 is formed. 3. A triangular-pyramidal cube-corner type in which a retroreflective element forming a specular reflective prism type retroreflective element is cut out by parallel V-groove groups whose cross sections intersecting in three directions are substantially symmetrical. An image-formed retroreflective article according to claim 1, which is a retroreflective element pair. 4. A triangular-pyramidal cube-corner type in which a retroreflective element forming a specular reflective prism type retroreflective element is cut out by parallel V-groove groups whose cross sections intersecting from three directions are substantially symmetrical. The retroreflective article on which an image is formed according to claim 3, wherein the retroreflective element pair is one in which the V-grooves in three directions have different depths in at least one direction. 5. The photoreactive resin layer provided on the specular reflection layer on the second surface is any of photopolymerizable, photocondensable, photocrosslinkable and photodegradable. A retroreflective article on which the image according to (1) is formed. 6. The photoreactive resin layer provided on the specular reflection layer on the second surface is any one of photopolymerizable, photocondensable, photocrosslinkable and photodegradable, and the photoreactive resin layer is formed. The minimum thickness of the layer to be formed is 10 to 200 μm.
A retroreflective article having the image according to any one of 1. 7. The retroreflective article with an image formed thereon according to claim 1, wherein the photoreactive resin layer provided on the second surface of the specular reflection layer is in the form of a sheet. 8. The image-formed retroreflective article according to claim 1, wherein the method of selectively irradiating light is a light-shielding mask method and / or an optical scanning method. 9. A retroreflective article comprising a first layer having a flat first surface and a second layer comprising a retroreflective element layer having a second surface from which a specular reflection layer is exposed. , A. Step of setting the photoreactive resin layer on the specular reflection layer on the second surface B. Step of partially reacting the photoreactive resin by selective light irradiation C. Select area of the photoreactive resin layer Partly removing step D. Method of forming image by step of forming image by partially removing specular reflection layer. 10. The image according to claim 9, wherein the photoreactive resin layer provided on the specular reflection layer on the second surface is photopolymerizable, photocondensable, photocrosslinkable or photodegradable. How to form. 11. The photoreactive resin layer provided on the specular reflection layer on the second surface is photopolymerizable, photocondensable, photocrosslinkable or photodegradable, and forms a photoreactive resin layer. The method for forming an image according to claim 9 or 10, wherein the minimum portion of the layer to be formed has a thickness of 10 to 200 µm. 12. The method according to claim 9, wherein the photoreactive resin layer provided on the specular reflection layer on the second surface is supplied in the form of a sheet and is provided on the specular reflection layer on the second surface. A method of forming an image according to claim 1. 13. The method for forming an image according to claim 9, wherein the method of selectively irradiating light is a light shielding mask method and / or an optical scanning method.