Type of road markings for supporting the environment detection of vehicles

Abstract

A radiation-reflecting road marking, comprising: metal particles having a diameter of between 0.5-2.5 mm, wherein the metal particles are particles comprising aluminum, magnesium, zinc or an alloy thereof. Also, a method for producing the radiation-reflecting road marking, where the radiation-reflecting road marking is a cold plastic, by mixing components of a two-part system, if necessary, to form a mixture, applying the mixture to a road surface, and adding the metal particles and optionally glass beads during or directly after an application of the cold plastic to the road surface.

Claims

1. A radiation-reflecting road marking, comprising: a matrix material; and metal particles having a diameter of between 0.5-2.5 mm, wherein the metal particles are spherical, oval, or rounded particles comprising a metal selected from the group consisting of aluminum, magnesium, zinc, and any alloy thereof, and wherein the metal particles are in the form of solid or hollow metal particles consisting of the metal, the metal particles comprise a core of a different material coated with the metal, or the metal particles comprise a core of the metal coated with glass, poly(methyl methacrylate), or polycarbonate.

2. The radiation-reflecting road marking according to claim 1, wherein the metal particles consist of the metal.

3. The radiation-reflecting road marking according to claim 1, wherein the metal particles are spherical.

4. The radiation-reflecting road marking according to claim 1, wherein the metal particles consists of aluminum.

5. The radiation-reflecting road marking according to claim 1, wherein the radiation-reflecting road marking is a prefabricated adhesive tape.

6. The radiation-reflecting road marking according to claim 1, wherein the radiation-reflecting road marking is a water-based paint.

7. The radiation-reflecting road marking according to claim 1, further comprising: glass beads on a surface of the radiation-reflecting road marking.

8. The radiation-reflecting road marking according to claim 1, wherein the metal particles are situated on a surface of the radiation-reflecting road marking.

9. The radiation-reflecting road marking according to claim 1, wherein the radiation-reflecting road marking reflects microwaves and/or infrared radiation.

10. The radiation-reflecting road marking according to claim 1, wherein the metal particles are provided on a surface of the matrix material with an adhesion promoter and/or the matrix material comprises an adhesion promoter.

11. The radiation-reflecting road marking according claim 10, wherein the adhesion promoter is at least one adhesion promoter selected from the group consisting of a silane, a hydroxyester, an aminoester, an urethane, an isocyanate and an acid copolymerized with a (meth)acrylate.

12. The radiation-reflecting road marking according claim 1, wherein the radiation-reflecting road marking is a cold plastic.

13. The radiation-reflecting road marking according to claim 12, wherein the cold plastic is produced from a two-part reactive resin in which a first component comprises 1.0 to 5.0 wt % of an initiator, and a second component comprises 0.5 to 5.0 wt % of an accelerator, and in that the two-part reactive resin comprises: 0.1 wt % to 18 wt % of a crosslinker, 2 wt % to 50 wt % of a monomer, 0 wt % to 12 wt % of an urethane (meth)acrylate, 0.5 wt % to 30 wt % of a prepolymer, 0 wt % to 15 wt % of core-shell particles, 7 wt % to 15 wt % of an inorganic pigment, and 30 wt % to 60 wt % of mineral fillers.

14. A method for producing the radiation-reflecting road marking according to claim 12, the method comprising: optionally mixing components of two-part system, thereby forming a mixture; applying the mixture to a road surface; and adding the metal particles and optionally glass beads during or directly after an application of the cold plastic to the road surface.

15. The radiation-reflecting road marking according to claim 13, wherein the initiator is dilauroyl peroxide, dibenzoyl peroxide or both.

16. The radiation-reflecting road marking according to claim 13, wherein the accelerator is a tertiary, aromatically substituted amine.

17. The radiation-reflecting road marking according to claim 13, wherein the inorganic pigment is titanium oxide.

Description

EXAMPLES

(1) The following examples have been conceived as an instruction for performing the present invention. All of these examples exhibit the same good road marking qualities as the parent formulas without metal particles. The formulations of the examples additionally exhibit good reflection of microwave radiation with a frequency of 24 GHz.

(2) For the preparation of the examples, aluminium particles from Eisenwerk Wrth GmbH with the designations Granal S-180 and Granal S-40 were used. Aluminium particles of these kinds are sold for use as blasting abrasives. The form of the particles is rounded in each case, with a non-uniform surface.

(3) Granal S-180 particles have a size of between 1.8 and 2.5 mm. Granal S-40 particles have a size of between 0.4 and 0.8 mm.

(4) Glass beads used are surface-silanized Vialux 20 glass beads from Sovitec. These glass beads have diameters in a range between 600 and 1400 m.

(5) The metal particles and the glass beads (where present) are applied to the surface of the cold plastic using a pressurized gun. Alternatively, however, simple application by scattering would also be possible. That would lead to reduced, but nevertheless sufficient, adhesion.

(6) The formula of the cold plastic used is based on the composition disclosed as Example 2 in WO 2012/100879. That example can be consulted in particular for the composition of the core-shell particles.

Example 1

(7) Intimately combined with 63 parts of methyl methacrylate and 5 parts of butyldiglycol dimethacrylate are 0.05 part of Topanol-O, 13 parts of DEGACRYL M 339, 9 parts of core-shell particles and 0.5 part of paraffin, and this mixture is heated at 63 C. with vigorous stirring until all of the polymer constituents are dissolved or dispersed. For curing, 1 part of benzoyl peroxide (50 wt % strength formulation in dioctyl phthalate) and 2 parts of N,N-diisopropoxytoluidine are added and are incorporated by stirring at room temperature (21 C.) for one minute.

(8) To effect curing, the composition was poured onto a metal plate. Within one minute after poured application, the surface is strewn with Granal S-180 particles. The amount used corresponds to 280 g of particles/m.sup.2. After curing has taken place, specimens are produced in accordance with DIN 50125. Pot life: 14 min; cure time: 30 min; flow time (4 mm): 252 sec

Example 2

(9) Like Example 1, but using Granal S-40 instead of Granal S-180, in corresponding amounts.

Example 3

(10) Like Example 1, but with additional scattered application, from a pre-prepared mixture with the Granal S-180 particles, of glass beads, in an amount corresponding to 280 g/m.sup.2.

Example 4

(11) Like Example 3, but with the Granal S-180 particles being incorporated into the composition by stirring together with the core-shell particles, and with scattering of glass beads only following poured application.

Comparative Example

(12) Like Example 4, but without aluminium particles.

(13) The radar, or radar backscatter, cross section (RCS) of the marking samples was measured on a marking with a size of 1010 cm. Measurement took place orthogonally to the application area, using a 76 GHz radar sensor.

Results

(14) Example 1: The radar cross section ascertained is 0.0029 m.sup.2. Example 2: RCS=0.0013 m.sup.2 Example 3: RCS=0.0021 m.sup.2 Example 4: RCS=0.0014 m.sup.2 Comparative example: RCS=0.00021 m.sup.2

(15) For an example wavelength of 76 GHz, the examples show a reflection intensified by a factor of at least 60 relative to the comparative example, with an analogous marking not equipped with metal particles.