| 摘要 |
PROBLEM TO BE SOLVED: To provide a process capable of forming colored films in the rear surface parts and flank parts of microspheres to have an extremely small and uniform thickness and executing the coloring and designing of patterns, characters, etc., in a displayable form as a process for producing microsphere exposure type retroreflectors. SOLUTION: Hot melt adhesives 12 of 90 deg.C thermal softening temp. and light reflective films 13 are laminated on an adhered material 11. After the colored films 14 of 70 deg.C thermal softening temp. and about 3μin thickness are laminated thereon, the transparent microspheres 15 are arrayed in a single layer thereon. The entire part is thermal-pressurized in this state at 110 deg.C to make nearly the hemispherical parts of the microspheres 15 enter the adhesives 12 while the light reflective films 13 are pressed and deformed through the colored film 14, by which the retroreflectors 20 having the light reflective films 13 adjacent to the rear surface parts of the microspheres 15 and having the colored films 14 adjacent to the front surface parts of the flank parts of the microspheres 15 are formed.
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