CPC E01F 15/06 (2013.01) [D07B 1/148 (2013.01)] | 8 Claims |
1. A vision guide with a light guiding rod comprising:
a rope member formed by twisting plural strands and used outdoors;
a light guiding rod of circumferentially light emitting type which is adheringly wound around spiral indentations formed between the strands on an outer circumference of the rope member, the light guiding rod having a core layer made of an acrylic-based resin and a clad layer provided on an entire outer circumference of the core layer when viewed in cross-section and made of a fluorine-based resin, wherein:
the acrylic-based resin is a mixture of an acrylic-based elastomer with an acrylic-based hard resin with a mixing ratio of the latter to the former being 95:5 to 70:30,
0.01 to 5 parts by weight of titanium oxide having ultraviolet rays absorbing action is added to the fluorine-based resin, and
a thickness of the clad layer is equal to or less than 1.0 mm; and
a light source attached to an end portion of the light guiding rod, wherein:
amount of change in luminance of the guiding rod in test time over duration of 1000 hours by an accelerated weathering tester with a black panel temperature of 63 degrees Centigrade is contained within a range of ±10%;
amount of change in each numerical value of chromaticity [x, y] thereof is contained within a range of ±0.02;
flexural modulus of elasticity of the light guiding rod under the atmosphere of −20 degrees Centigrade is contained within a range of 0.5 to 5.0×103 MPa;
the rope member is formed by twisting the strands at a twisting angle from 10° to 20°; and
the spiral indentations are uniformly formed with a pitch from 100 mm to 200 mm.
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