Optical sheets and optical components

Abstract

To provide an optical sheet with which a reduction in half mirror layer reflectance and a change of half mirror layer color tone are accurately suppressed or prevented, and which is imparted excellent long-period durability, and an optical component that includes such an optical sheet and excels in reliability.SOLUTION: An optical sheet 10 according to the present invention is composed of a laminate in which a first substrate 1, a half mirror layer 3, and a second substrate 2 are laminated in the order stated. When the optical sheet 10 is irradiated with an ultraviolet ray for 1000 hours from the first substrate 1 side using a sunshine weather meter in conformity with cycle No. 1 of method in table 3-A of JIS K 7350-4, reflected light from the optical sheet 10, thereafter, satisfies that a change of color of the optical sheet 10, as measured in compliance with ISO 11664-4, is less than 5.0 [ΔE].SELECTED DRAWING: Figure 1

Claims

1. A first substrate composed mainly of a light-transmitting resin material, A half-mirror layer is laminated on one side of the first substrate, which transmits a portion of the incident light and reflects the remainder, A second substrate is constructed primarily from the aforementioned resin material and laminated on the side opposite to the first substrate of the half-mirror layer, An optical sheet comprising a laminate comprising a coating layer containing a (meth)acrylic resin as the main material and an ultraviolet absorber, which is laminated on the surface opposite to the half-mirror layer of at least one of the first substrate and the second substrate, After irradiating the optical sheet with ultraviolet light for 1000 hours from the first substrate side using a sunshine weather meter in accordance with Table 3-A method - cycle No. 1 of JIS K 7350-4, the remaining reflectance of the reflected light at 550 nm reflected by the optical sheet is 85% or more, and the color change of the optical sheet, measured in accordance with ISO 11664-4, is less than 5.0 [ΔE]. The optical sheet is characterized in that the ultraviolet absorber contained in the coating layer comprises a (meth)acryloyl group that is reactive with the (meth)acrylic resin, and its content in the coating layer is 1.0% by weight or more and 10.0% by weight or less.

2. The optical sheet according to claim 1, wherein the resin material is a polycarbonate-based resin.

3. The optical sheet according to claim 1 or 2, wherein at least one of the first substrate and the second substrate contains an ultraviolet absorber.

4. The optical sheet according to any one of claims 1 to 3, wherein the half-mirror layer comprises a high refractive index layer and at least one low refractive index layer having a lower optical refractive index than the high refractive index layer.

5. The optical sheet according to any one of claims 1 to 4, further comprising an adhesive layer having light transmittance, provided between the half-mirror layer and the second substrate, and joining the half-mirror layer and the second substrate.

6. The optical sheet according to any one of claims 1 to 5, further comprising an adhesion layer provided between the first substrate and the half-mirror layer, the adhesion layer being provided between the two and the half-mirror layer, the adhesion layer being provided between the two and the half-mirror layer, and comprising at least one of acrylic resin, inorganic acrylic resin, and organosiloxane as the main material.

7. An optical component characterized by comprising an optical sheet as described in any one of claims 1 to 6.

Images