TEXTURED REFLECTIVE SYNTHETIC LEATHER

Abstract

A retroreflective article in which the retroreflective optical elements are arranged to create a textured surface which improves abrasion performance and reflectivity at certain entrance and observation angles.

Claims

1. A retroreflective material comprising i. A retroreflective layer of reflective elements attached to a binder layer ii. A textured surface such that the layer of reflective elements are oriented in multiple directions

2. A retroreflective material as in claim 1 which has a colorizing composition applied to the surface

3. A retroreflective material as in claim 1 which contains an aluminum vapor coat

4. A reflective material as in claim 1 which does not contain an aluminum vapor coat reflective material as in claim 4 which has a pigmented or colored binder layer

6. A reflective material as in claim 1 which the texture is provided through embossing

7. A reflective material as in claim 1 which comprises a thermoplastic polyurethane

8. A reflective material as in claim 1 which comprises a synthetic leather

9. A reflective material as in claim 1 which comprises a woven fabric backing

10. A reflective material as in claim 1 which comprises a non-woven fabric backing

11. A reflective material as in claim 1 which comprises an abrasion resistant coating on the surface of the reflective elements.

12. A reflective material as in claim 1 which comprises a thermoset polyurethane

13. A reflective material as in claim 1 which comprises a textured substrate with thicknesses between 0.001 and 0.25.

14. A reflective material as in claim 1 which comprises a textured substrate with a difference of 0.0002 and 0.10 inch between the thinnest and thickest points.

15. A reflective material as in claim 1 including a printed pattern on the reflective

16. A reflective material as in claim 1 which has a transparent bonding adhesive between the glass beads and the textured substrate.

17. A method of preparing the reflective material of claim 1, comprising heat lamination of the reflective material having an adhesive backing to a suitable substrate.

18. A method of preparing the reflective material of claim 1, comprising the use of a liquid adhesive to adhere the reflective material to a suitable substrate.

19. A method of preparing the reflective material of claim 1, comprising pressure sensitive adhesion of the reflective material having an adhesive backing to a suitable substrate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 depicts the textured retroreflective film or fabric in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0018] The following detailed description presents certain embodiments to illustrate the inventive concepts, but which are meant by way of example only and are not intended to limit the scope of the invention in any manner. The inventive reflective material and process of applying to a textured support or substrate can be effectively given a textured or relief appearance and feel through the application of these material e.g., films, to a textured support/substrate.

[0019] As illustrated in FIG. 1, a textured material 4, formed from a synthetic material or natural material, includes a ribbed pattern, and an array of glass bead reflective elements 1 partially embedded in an adhesive binder layer 3, with an external vapor-deposited or chemically coated reflective material at 2. The reflective layer may also be a pigmented adhesive in the case that the reflective coating 2 is non-metallic or otherwise translucent. In this way, the color of the reflective material would be determined by the color of the adhesive. The adhesive is then affixed to a textured material 4. Optionally, a colorizing coating 5 may be coated on the exterior of the retroreflective elements.

[0020] Although FIG. 1 illustrates a ribbed pattern, the textured material could have other surface designs, such as, but not limited to grains, dimples, undulations, embossments, concentric quarter arcs, semi-circular arcs, arcuate, concentric geometric objects, e.g., circles, squares, rectangles, etc., random texturing, woven textures, fabric texture, etc.

[0021] Textured materials that are suitable for the present invention are most suitable if they are thermoset materials which are soft, but sufficiently cross-linked such that they do not deform under the heat of the application process. Examples include epoxys, cross-linked polyurethanes, cross-linked polyesters, cross-linked polyester-polyamids, rubber, polyvinyl chloride, acrylic-based polymers, etc. For example, a fabric, woven or non-woven (a fabric or mat of a natural or synthetic fibrous material, such as nylon, Orlon, Dacron, rayon, cotton, felts of animal hair, wool and the like impregnated with a cross-linked polyurethane resin. Alternatively, it has been found that thermoplastic materials can be sufficient given that their texture can be preserved through the application process. This is the case if the application temperature for applying the reflective material is far below the temperature at which the substrate deforms, softens, or melts.

[0022] A further aspect of this invention is the shape of the texture that is being imparted on the reflective material will heavily affect the performance of the textured reflective material. Sufficient texture depth, and the shape of the texture profile provide for the curvature of the reflective surface such that improve angularity is imparted as a function of the texture.

EXAMPLES

[0023] The invention will be further described by the following examples which are intended to illustrate the invention and not to limit the scope of the concepts in any manner.

[0024] Unless otherwise indicated the following test methods were used:

[0025] Retroreflectivity: Retroreflective brightness was measured using a retroreflectometer (RoadVista Model 932C) at the various entrance and observation angles listed.

[0026] Color: the daytime color of the colorized reflective materials were measured using a colorimetric spectrophotometer with 45/0 optics, a density status setting of T, a standard illuminant D65 light source setting, and a standard observer setting of 2.

Example 1

[0027] Four samples of Brilliant Colorized Reflective (a product of Safe Reflection) were prepared through colorization of 3M Scotchlite C725 retroreflective film, one bronze on color, one green in color, one dark blue in color, and one black in color using the method described in U.S. Pat. No. 8,470,394 B2.

[0028] A sheet of each color reflective material was cut into two identical pieces. One set of samples were laminated first to a flat, untextured fabric using a Hix 840 D clamshell-style heat press using a lamination temperature of 275-350 F, pressure setting between 10 and 60 psi, and dwell times between 10 and 20 seconds. What adhesives and characteristics are required? (the adhesive used in this case was a polyurethane-based hotmelt adhesive. The required adhesive depends on the surface treatment of the synthetic leather) A second set of the reflective materials were laminated onto a sample of textured synthetic leather (Majilite Corporation). The surface texture was dimpled, such as the embossed pattern on the surface of football leather.

[0029] After lamination, a sample was cross-sectioned with a razor blade, and a series of cross-sectional images were obtained under magnification. Overall thickness measurements were obtained using a micrometer, and these measurements were used as a basis for determining the relative dimensions of the textured reflective material. The overall thickness of the material was measured to be 0.032. Using the magnified images, the depth of each dimple was determined to be approximately 0.004 by measuring the difference between the thickest area and subtracting the thickness of the thinnest area. The lowest area between each dimple was determined to be approximately 0.002 wide. After lamination, the retroreflectivity of each material was tested at each of the entrance/observation angle pairs listed in the ANSI/ISEA 107 and ISO 20471 standards. The results are detailed in Table 1 below. As the entrance and observation angles were increased, the reflectivity of the textured sample improved in comparison to the flat samples. Due to the texturing effect, some of the glass beads along the edges of the raised bumps in the material are aligned at different angles and are such situated to improve reflectivity at wider angles.

[0030] Analysis of the data shows that due to the reflective material attaining the texture of the synthetic leather, the reflectivity profile change significantly. The low-entrance and low-observation angle measurement decreased slightly due to the misalignment effect of the texturing. The reduction in the flatness of the reflective surface causes reduced reflectivity at lower entrance and observation angles. The loss in reflectivity at lower entrance angles and observation angle of 5 is substantial, but less significant than the large increases in reflectivity at higher entrance and observation angles where the reflectivity of reflective materials is generally lower due to the nature of the materials.

[0031] The increase in reflectivity at high entrance and observation angles varies widely among the different samples tested, but significant increases were found in a few specific sets of measurement angles. This effect is substantial in data obtained with observation angles of 0.2, and entrance angle of 40, where the increase varies between 20% and 50% increased reflectivity between the flat and textured samples. A substantial improvement is also observed in the data obtained with an observation angle of 0.33 and entrance angles of 30 and 40, where the increase varies between 2% and 91%. As the observation angle increases to 1 and 1.5, the overall retroreflectivity is reduced, and more modest increases are observed at entrance angles of 30 and 40.

[0032] The improvement in the reflectivity at wider angles as a result of creating texture results in improved visibility of the reflective material to a driver at night when the reflective material surface is situated such that it is not facing the headlights directly, and when the wearer of the reflective material is further away from the roadway (entrance angle).

TABLE-US-00001 TABLE 1 Retroreflectivity of flat and textured colorized retroreflective material. Reflectivity (cd/lux-m2) Obs. Ent. Dark Dark Angle Angle Min- Bronze/ Bronze/ Green/ Green/ Blue/ Blue/ Black/ Black/ (deg) (deg) imum Flat Textured Flat Textured Flat Textured Flat Textured 0.2 5 330 390 271 383 321 345 302 332 265 20 290 116 126 136 140 107 107 115 105 30 180 35.9 42.89 42.6 55.7 31.6 35.2 36.8 36.5 40 65 8.85 14.9 10.3 16.9 6.9 8.3 5.79 8.73 0.33 5 250 231 195 250 229 230 203 228 175 20 200 101 99 108 114 83.9 90.4 98.1 87.2 30 170 30.2 40.7 41.8 51.9 30.8 31.8 32.2 33.4 40 60 9.42 15.1 7.9 15.1 6.82 7.91 4.59 8.04 1 5 25 69.6 65.5 59.5 58.5 53.7 108 43.1 39 20 15 50 47.5 40.4 43.2 38.1 68 34.2 28.8 30 12 27.3 28.6 27.4 26.7 19.2 25.3 21.7 19.2 40 10 11.3 14.2 10.2 13.5 8.7 6.54 7.79 8.77 1.5 5 10 35.6 34.8 29.6 29.9 24.9 25.9 19.6 19.9 20 7 33.3 31.2 27.1 26.6 21.8 21.8 15.9 16.3 30 5 20.5 20.9 16 18.2 13.2 13.8 11.5 10.3 40 4 10.5 11.7 9.28 10.5 7.28 7.2 6.16 6.5