JPH0796107B2 - Method of uniformly fixing glass beads and structure of coating layer in retroreflective coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a method for uniformly adhering glass beads in retroreflective coating, which is applied to the surface of an object so that the object can be clearly recognized by retroreflection. And the structure of the coating layer.

[Conventional technology]

Conventionally, glass beads are arranged side by side as a means for clearly recognizing objects such as helmets by retro-reflected light, and generally a binder is applied to the surface of the reflective layer formed on the surface of the material to be coated. It has a structure in which a myriad of fine glass beads are adhered side by side and the surface of the glass bead layer is covered with a transparent surface film, and in order to obtain effective retroreflection, the fine glass beads are evenly distributed on the reflective layer. Moreover, it is necessary to apply it in a single layer. For this reason, solvent-based paints have conventionally been used as the binder, and the glass beads are attached using the adhesive force of the binder.

[Problems to be solved by the invention]

However, with this method, it is extremely difficult to capture the moment when the appropriate adhesive strength of the binder is revealed, and the viscosity of the binder is low when a large amount of solvent remains in the binder, so the paint penetrates between the glass beads. Then, the phenomenon of double adhesion of glass beads occurs, and conversely, when the solvent in the binder is excessively diffused, the adhesive strength of the binder surface is reduced, and there is a problem that the glass beads do not adhere well. . Therefore, in the conventional retroreflective structure,
In addition to variations and unevenness in the arrangement of glass beads depending on the coating environment and coating shape, etc., for objects that take time to paint, due to the time difference between the start and end of coating, there is a difference in the diffusion of the above solvent, and the adhesion of glass beads There were variations and unevenness.

Further, by using an adhesive instead of a solvent-based paint as a binder in order to solve the above problems, the variation in adhesion of glass beads is eliminated, but the problem that the adhesive strength decreases and the strength performance deteriorates. Had.

The present invention was devised in view of the above problems, and proposes a method of uniformly coating and fixing glass beads in retroreflective coating, and provides a structure of a retroreflective coating layer formed by the method. The purpose is.

[Means for solving problems]

The method for uniformly adhering glass beads and the structure of the coating layer in the retroreflective coating of the present invention have an initial adhesive force for adhering the glass beads, and after adhering the glass beads to the surface, by irradiation with ultraviolet rays. The purpose of this is to achieve the purpose by using an ultraviolet-curable coating that solidifies as a binder. The method of uniformly fixing glass beads in retroreflective coating is as follows: a. Apply an ultraviolet curable paint, and after drying, irradiate and solidify it with ultraviolet light to form an adhesive layer. A. A reflective layer is formed on the surface of the adhesive layer by vapor deposition of aluminum, metallic coating or white coating, and c. After applying an ultraviolet curable coating on the surface of the reflective layer to an appropriate thickness, d. Fine glass beads are scattered on the surface of the ultraviolet curable coating material to adhere the glass beads to form a single glass bead layer, and e. Forming a binder layer for fixing the reflective layer and the glass bead layer by irradiating and solidifying an appropriate amount of ultraviolet light on the above ultraviolet curable coating material; The surface of the glass bead layer is coated with urethane coating a plurality of times while being dried to form a transparent coating layer having a flat surface.

Therefore, the structure of the coating layer in the retroreflective coating according to the present invention is such that the adhesive layer obtained by applying an ultraviolet curable coating, drying and then irradiating and solidifying it with ultraviolet rays, and aluminum vapor deposition, metallic coating on the surface of the adhesive layer Or a reflective layer constituted by white coating, and a binder layer formed by applying an ultraviolet curable coating on the surface of the reflective layer to an appropriate thickness, irradiating and curing an appropriate amount of ultraviolet rays to solidify the reflective layer and the glass bead layer. Before the solidification of the UV-curable coating material, one surface of the glass bead layer is prepared by spraying fine glass beads on the surface of the coating material and adhering the glass beads, and the surface of the glass bead layer is dried several times while the urethane coating material is dried. It is formed by coating and is laminated by a transparent coating layer having a flat surface.

[Action]

In the method and structure of the retroreflective coating, since the binder layer for fixing the reflection layer and the glass bead layer is constituted by the ultraviolet curable coating material, the binder is applied unless the ultraviolet ray is irradiated for a predetermined time after applying the ultraviolet curable coating material. The layer does not solidify. Therefore, when fine glass beads are sprayed on the surface of the UV-curable coating material, the glass beads adhere to one surface due to the adhesive force of the UV-curing coating material to form one glass bead layer, which is formed by the transparent sphere of each glass bead. A retroreflection layer for irradiation light is formed. After that, the binder layer is formed by irradiating ultraviolet rays to the ultraviolet curable coating and solidifying it.Because the binder layer is not formed unless it is irradiated with ultraviolet rays, there are variations in the glass bead layer due to uneven solidification and the like. Without causing unevenness
A uniform single-layer glass bead layer is obtained.

〔Example〕

An embodiment of the method for uniformly adhering glass beads in retroreflective coating according to the present invention will be described below according to the structure of the retroreflective coating layer shown in FIG.

Coating Step (1) Pretreatment After the surface of the retroreflective coating base material a is wiped off with IPA, the surface is ultrasonically cleaned with Freon gas.

(2) Formation of adhesive layer 1 a. Apply UV curable paint to a thickness of about 20 μm.

B. After drying at 75 ℃ for 10 minutes, cool at room temperature for 5 minutes or more.

C. After being solidified by irradiation with ultraviolet rays, the adhesive layer 1 is formed by cooling at room temperature for 5 minutes or more.

(3) Formation of reflective layer 2 a. The reflective layer 2 is formed on the surface of the adhesive layer 1 by vapor deposition of aluminum, metallic coating or white coating.

(4) Formation of glass bead layer 4 a. The surface of the reflective layer 1 is coated with an ultraviolet curable coating material having a thickness of about 3 μm.
After being applied in a thickness of 5 μm, it is left at room temperature for 5 minutes or more.

(2) After drying at 75 ° C for 3 minutes, cool at room temperature for 1 minute or more.

C. Next, fine glass beads are applied to the surface of the UV-curable coating.
Spread 3,3 ... evenly and stick the glass beads 3,3 ...
The glass beads layer 4 of a single layer is adhered.

(5) Formation of Binder Layer 5 a. After the ultraviolet curable coating material is irradiated with an appropriate amount of ultraviolet rays to be solidified to form a binder layer 5 for fixing the reflection layer 2 and the glass bead layer 4, the binder layer 5 is cooled at room temperature for 5 minutes or more.

(6) Formation of transparent coating layer 6 a. A two-component urethane paint is applied to the surface of the glass bead layer 4 in a thickness of about 20 μm, and then left at room temperature for 30 minutes or more.

B. The above 6-a step is repeated several times.

C. About 2μm urethane paint of desired color on the surface
The transparent coating layer 6 having a color finishing layer is formed by coating with a thickness of 20 μm.

(7) Post-processing a. Leave at room temperature for 8 hours or more.

(2) After drying at 75 ° C for 2 hours, cool at room temperature for 1 hour or more.

The structure of the retroreflective coating layer formed in the above step is a laminated structure composed of an adhesive layer 1, a reflective layer 2, a binder layer 5, a glass bead layer 4, and a transparent coating layer 6 formed on the surface of the retroreflective coating substrate a. It is what constitutes.

〔The invention's effect〕

Since the method of uniformly fixing glass beads and the structure of the coating layer in the retroreflective coating according to the present invention are configured as described above, the binder layer for fixing the reflection layer and the glass bead layer is constituted by the ultraviolet curable coating material. As a result, the glass beads scattered on the surface of the ultraviolet curable coating adhere evenly and form a single layer, which is characterized in that a uniform single-layer retroreflective layer is formed. Is extremely effective.

[Brief description of drawings]

The drawing is an enlarged cross-sectional view showing the structure of a coating layer which has been subjected to the method for uniformly adhering glass beads in retroreflective coating according to the present invention. DESCRIPTION OF SYMBOLS 1 ... Adhesive layer, 2 ... Reflective layer 3 ... Glass beads, 4 ... Glass bead layer 5 ... Binder layer, 6 ... Transparent coating layer a ... Retroreflective coating substrate

Claims (2)

[Claims] 1. A washed retroreflective coated surface a. Apply an ultraviolet curable paint, and after drying, irradiate and solidify it with ultraviolet light to form an adhesive layer. A reflective layer is formed on the surface of the adhesive layer by aluminum vapor deposition, metallic coating or white coating. After applying an ultraviolet curable coating on the surface of the reflective layer to an appropriate thickness, d. Fine glass beads are scattered on the surface of the ultraviolet curable coating material to adhere the glass beads to form a single glass bead layer, and e. Forming a binder layer for fixing the reflective layer and the glass bead layer by irradiating and solidifying an appropriate amount of ultraviolet light on the above ultraviolet curable coating material; A method for uniformly adhering glass beads in retroreflective coating, characterized in that the surface of the glass bead layer is coated with urethane coating several times while being dried to form a transparent coating layer having a flat surface. 2. An adhesive layer obtained by applying an ultraviolet curable coating, drying and irradiating it with ultraviolet rays and solidifying it, and a reflecting layer formed by vapor deposition of aluminum, metallic coating or white coating on the surface of the adhesive layer, After coating the surface of the reflective layer with an ultraviolet curable coating in an appropriate thickness, a binder layer formed by irradiating and curing an appropriate amount of ultraviolet rays to fix the reflective layer and the glass bead layer, and before solidifying the ultraviolet curable coating, One layer of glass beads with fine glass beads scattered on the surface and the glass beads adhered to the surface, and a urethane coating on the surface of the glass beads layer is applied multiple times while drying, and a transparent coating with a flat surface. Structure of coating layer in retroreflective coating characterized by comprising layers.