DE2441546A1 - TRAFFIC MARKING AND METHOD OF MANUFACTURING IT - Google Patents

Description

Dr. Michael Hann
63 casting
Ludwigstrasse 67

Robert W. Norris, Jr., Salem, Oregon, USA

TRAFFIC MARKING AND PROCEDURE FOR THEIR PRODUCTION

Priority: September 5, 1973 / U S A / Ser. No. 394 587

This invention relates to structures having a paved roadway and traffic marking adhered thereto. In addition, the invention is also directed to a method for applying traffic marking to a paved roadway.

The marking of traffic surfaces with signs that Directing traffic, such as lanes, center lines, or road edges, is common practice. Such traffic markings on Roadways, which can consist of asphalt or concrete, for example, often contain reflective means such as glass spheres.

The traffic markings are of continuous wear and exposure to atmospheric and street chemicals subject to which periodic renewal is required. When painting compounds for traffic markings are applied to an area with traffic, there is a risk of that the marking remains on the tires of the vehicles during a period in which it has not yet dried.

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is taken and transmitted, creating confusing and undesirable Signs lingering on the traffic surface. To circumvent these difficulties, colored cones or flags are often used as temporary obstacles on the road Road surface arranged to protect the marker until it dries. These «temporary obstacles must then be removed in a separate operation.

Various systems have already been proposed

to obtain coatings that have short times inside

half of which they leave no traces when driving, and which can be applied without an additional one Protection would be needed. However, these known systems require the use of relatively expensive materials and / or the use of expensive and complex equipment for application.

As mentioned earlier, most traffic marking paints use a variety of light reflective or scattering particles, preferably glass beads or glass spheres are used. The effect of glass balls in traffic markings has been extensively studied, taking their optimal light reflection, modifying their properties treated by the coating composition and the secure embedding of the balls in a paint film.

The object of the present invention is to provide a traffic marking to indicate for structures with a paved roadway, it has only short drying times and is easy and economical to apply to the paved roadway of the structure leaves.

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According to the invention, this object is achieved by a traffic marking solved that contains

(A) a pigmented dried coating composition which is a contains organic synthetic resin and as such is dried within about 6 minutes and embedded in it,

(b) at least one single layer of a light-reflecting small-particle material, the predominant part of the particles of this material is embedded in the coating to at least half of their mass and have a diameter larger than the thickness of the coating film, and

(c) the particles of light reflective particulate matter are embedded in close proximity to one another so that they are less than about their average diameter from one another are away.

The compositions from which such traffic markings are made have significantly shorter drying times than the same compositions without the particulate matter. Drying is understood to mean any process which makes the paint film solvent-free, e.g. through evaporation, cooling, chemical crosslinking, Polymerization and the like.

In a preferred embodiment of the invention contains The system for traffic marking uses a pigmented organic binder that works within 3 minutes or less dries at the applied wet film thickness. The organic

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2 A4 1 5 46

The coating compound is applied as a relatively thin film, e.g. in a wet thickness of about 0.38 mm or less, preferably about 0.25mm. The reflective materials embedded in the dry cover film are in the cover e.g. by dropping or blowing the small-sized material into the moist film before it dries been. The particulate reflective material is of such a particle size that it is essentially penetrates into the depth of the binder or the coating film so that the base of the particles is in the vicinity of the Substrate is or substantially rests on it. The majority of the particles form this material at least one single layer in which the particles are at least are half embedded in the layer of the binder, with the particles in close proximity to each other, so that they touch or are only separated by a very short section of film attached to some of the particles can stick, but appear to the eye as if they were essentially touching. In general they are individual particles of the finely divided material are separated by a distance no greater than the average Particle diameter.

In another preferred embodiment, a thin, pigmented liquid paint film is applied to the traffic surface and there is then an excess applied to small-sized material that is sufficient to completely cover the paint film. The excess of the fine-grained material that is not in the paint film

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embedded and essentially not bound by it remains on the road sign at least temporarily to give it additional protection. The road sign is dry in such a short time that this temporary protection is also useful is. By "substantially bound" is meant that the small-scale material is bound in such a way that it is swept by the action of a broom with light pressure is not replaced.

The liquid coating compound used to produce the traffic markings, which is an organic synthetic resin Contains carrier can vary widely in their composition. Such coating compositions are well known in the art and therefore do not have to be described in detail. A large number of coating compounds are also known, which are suitable for the production of coatings on such materials, such as concrete or asphalt, and therefore particularly suitable for the application of traffic signs are. Any organic polymeric binder can be used in the invention which has a sufficient Adhesion to the substrate and to the particulate material possesses the necessary mechanical to the marking system To give integrity and which, after formulation to a pigmented coating system, gives a coating mass, that within about 6 minutes or less, preferably within 3 minutes or less, to an unmarked over train dries. This drying time is the drying time of the coating composition as such without addition of the light-reflecting, small-scale material.

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The organic synthetic resin used as a carrier in the formulation can be either a thermoplastic or a thermoplastic be thermosetting resin. In addition to the organic carrier resin and the pigment, the formulation can also contain other customary ones Contain ingredients and additives, such as solvents, plasticizers, crosslinking agents, catalysts, Flux and the like. As a rule, the coating compound contains a solvent to give it the desired viscosity and drying time. The coating compound however, it can also be a composition with a high solids content or a solvent-free composition be, such as compositions with high melting points, polymer-monomer systems, for example of unsaturated Polyesters and styrene, or liquid systems that harden when used, such as polyurethane systems or epoxy systems.

In solvent-based systems, for example, acrylic "; resins, vinyl resins, alkyd resins, polyester resins, epoxy resins, urethane resins, phenolic resins and amino resins are used Find.

The coating composition is pigmented in such a way that the traffic marking can be seen under the various conditions. Commonly used in coating compounds for traffic signs yellow, ^one white and red used, although pigments any colors can be used. Typical pigments are titanium dioxide (rutile and anatase), lead chromate (chrome yellow) and the like. The compositions can also contain other pigments as extenders, such as silica, clay, calcium sulfate, calcium carbonate, magnesium silicate

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and the same. The coloring of the compositions can be achieved by using a colored light reflective small-scale material can be reinforced or generated solely by it.

The pigmented coating mass is generally applied to the traffic surface in the usual way, preferably by spraying. In most cases the moist or wet transfer film will be about 0.38 ram thick or less, preferably about 0.25 mm or less. With films of a wet thickness of about 0.25 mm or less short drying times on the order of a few seconds are obtained.

The light-reflecting or light-scattering small-scale material that is embedded in the coating compound in the invention can vary greatly in the Asian composition. It includes such light-diffusing materials as sand, but also truly reflective materials such as glass spheres.

Glass spheres are particularly suitable reflective materials of this type. The balls available on the market are generally not homogeneous with regard to their size and are typically sold as products that contain predominantly spheres that are a specific mesh size of a sieve, but are held back by a special smaller mesh size of a sieve. If e.g. 0.38 mm balls are used, the vast majority

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part of the balls have a diameter of about 0.38 mm, but balls are usually also present in the ball material, which have a slightly smaller diameter. Typical glass spheres that meet the "Federal Specification TTB 1325A, Type 1, Class A "have the following characteristics:

100% pass through mesh size 20, 80 - 100 % pass through mesh size 30, 18 - 35 % pass through mesh size

Another preferred material is round sand known as "Ottawa sand" which as opposed to ordinary Sand has a relatively smooth surface and a spherical shape. Two particularly suitable varieties of this sand are:

AWAY

(Crystal) (Federal Fine)

AFS grain size 38 47

actual surface

(cra ² / g) 72 97

Base permeability 246 252

theoretical surface

(cm ² / g) 62 80

Area coefficient 1.2 1.2

Density (unpressed) (g / cm ³ ) 3.076 3.060

Density (pressed) g / cm) 3.156 3.124

% held back by
US sieve No.

30th 1

40. 36 · 19

50 45 43

ioo 509810/0359 ¹ ^ ² ^

140 - 3

200 - 1.0

Other suitable light reflective particulate materials j which can be used in the invention are organic polymer particles, which are preferably in the form of of balls or pearls. Such materials are, for example, polymethyl methacrylate, polystyrene, vinyl chloride copolymers and vinyl acetate copolymers. These materials can be used alone or in combination with glass spheres, spherical sand, common sand, crushed glass or other mineral particles can be used e.g., have a particle size between about 20 to about 50 mesh.

The light-reflecting particulate material should have a particle size such that its predominant portion has a diameter which is greater than the wet thickness of the coating film, but on the other hand the particle size should be small enough that at least the initial layer of the particulate material is at least half its mass in the film of the coating composition is embedded. If the material is spherical, the circumference of the sphere should be embedded in the coating compound. In the invention, a particulate material can be used, the particles of which have substantially the same particle size. It is also possible to use the commercially available materials whose particle sizes extending over a range ^ ^ provided that the predominant proportion of these materials having the desired particle size ο Thus, one can see _e B "for a film with a wet

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thickness of 0.38 mm a small-scale material in the area use from about 0.48 to about 0.89 mm or about 20 to about 35 mesh.

The weight of light reflective adhesive material required to cover the unit area can be easily calculated by assuming that there is a single layer of uniform distributed pearls is present. For example, you can use the following formula:

W = r XVXG

2. 598S ²

in the W = the weight of the light-reflecting small - part material (g)

2 A = the unit area of the coating mass (cm)

V = the volume of the middle light-reflecting particle (cm ³ ) (0.52 χ D ³ )

G = the specific weight of the light reflective Particle (g / cm)

S = the distance (cm) between the centers of the light-reflecting particles that are uniformly distributed as a single layer in this coating composition where S is about 2D or less and D is the mean diameter of the light reflective Particle is in cm.

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For example, for an area of 929 cm when using glass spheres with a diameter of 0.381 cm, the touching each other an amount of about 50 g /

2
929 cm used.

As stated earlier, the traffic markings should According to the invention, the balls are spaced apart from one another by a maximum of about one diameter of the balls and preferably the balls should be about half a diameter or less apart. at In the example above, if the balls were removed from a diameter S 0.762 cm and W would be about 13 g be. With a distance between the balls of half a diameter, S would be 0.571 cm and W about 24 g «

So the above formula can be used to get the required weight of a spherical material to be calculated for any size. When heavier particles or larger diameter particles are used, the required weight of the particles is greater. If particles made of lighter materials, plastic, for example, a lighter weight of such particles is required.

If you use non-spherical particles like crushed glass or common sea sand, the mean diameter of the particles are taken as a basis.

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In the method for applying a traffic marking on a paved roadway according to the invention goes one in such a way that one

(A) on the road surface a moist, uncured film of a pigmented coating composition, which is an organic Contains synthetic resin and as such is tack-free within about 6 minutes after application dries, applies,

(b) at least one single layer of a light-reflecting, small-particle material on the moist film applies, with the majority of the particles of this material having a particle size such as that at least half of their mass in the movie

- The coating mass is embedded and the diameter but the particle is larger than the thickness of the film and

(c) the particulate material applies to the film in such a density that the individual particles are less than about their average diameter apart.

A moist film is understood to mean a film which has not yet dried or whose viscosity is still has not been raised to a point where the light-reflecting particulate material is no longer in penetrates the coating film.

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The light reflective particulate material can be applied to the coating film either by dropping it or preferably at a much higher speed, "e.g. with the aid of a pressurized spray gun.

Devices can be used to carry out the method are used that have been used so far for the application of traffic signs were used. In its simplest form, it is a vehicle on which two separate Pressure vessels are mounted. One of these containers holds the coating composition and the other the light-reflecting, small-scale material. The two materials are pressurized into two separate spray guns that apply the material to the extent that the vehicle is moved forward, first of all the paint film and then the fine-grained material.

In the marking system according to the invention for a 10 cm wide strips over a length of 1 km at least about 22 kg / km, preferably about 44 kg / km or more of the light reflective Small-sized material used when this has a specific gravity on the order of glass spheres or has sand.

The invention is not intended to be passed on to anybody Theoretically, it should be noted that the rapid drying of the coatings results in a tack-free state probably due to the fact that a Contact of the vehicle tires with the coating compound before it is dried or hardened is avoided. the

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dense packing of the small-sized material distributes the forces occurring and combined with the inertia, is avoided in that the vehicle tire causes the light-reflecting particles to be displaced, which is sufficient for the vehicle tires to absorb significant amounts of the coating compound, even though they do ■ is actually not yet completely dry.

In addition, in the invention, the individual layer of the light-refracting, small-scale material In addition, a substantial amount of fine-grained material is still bound to the paint film, although one suspects could be that just a single layer of the particulate material of the applied size from the film the coating compound could be bound. In practice, however, this is usually not the case Part is probably due to the fact that the small-scale material with a lateral force vector is applied with at least a portion of the coating material whirled up or onto the surfaces of the small-sized material is injected. Some of this material can move relatively quickly during use be displaced, but this part contributes significantly to the protection of the traffic marking after its application and thereby extends their service life.

Another advantage of the traffic markings according to the invention is that they are particularly wet Weather gives the vehicle track anti-slip properties.

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This makes these traffic markings particularly suitable as a so-called zebra crossing for pedestrians.

The invention is explained in more detail in the following examples. All information about parts and percentages are weight specifications, unless expressly stated otherwise.

example 1

The following coating composition is used:

Parts by weight 958 34% phthalic acid soy flaxseed
Alkyd resin (60% in toluene) 1 30th 12% lead 000 Chrome yellow (medium) 3 375 Rutile TiO ₂ 625 Talk 2 40 cationically modified clay
(Benton 38) 95 Methanol 000 Kaiζ ium carbonate
(maximum particle size 50 microns) 3 128 40 % chlorinated paraffin 1 500 chlorinated rubber, 20 cp 1 056 Methyl ethyl ketone 4th 45 Antifoam agents 45 Epichlorohydrin 527 Methylamyl acetate
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Using this coating composition, a conventional device such as a Binks No. 21 spray gun with a No. 69 D head and a No. 713 nozzle for the paint and a No. 21 Binks Gun with a No. 58 head and a No. R-30 nozzle for the small-scale material applied the traffic markings. Glass balls according to the "Federal Specification TT-B-1325A, Type 1, Class A "is used.

The apparatus was operated at a rapid walking pace, with the paint using the first spray gun a wet film thickness of 0.43 mm was applied. The application The glass balls took place immediately afterwards through the second spray gun. The air temperature was 27 C.

The times were measured in which no color pick-up or tracing occurred when a vehicle tire was used was rolled over the traffic marking. The vehicle tire was loaded with roughly the same weight per unit area, like a tire on a passenger car. In Figure 1, the times for no color pickup and no trace formation are different Amounts of glass balls applied. The number of balls is for a 10.16 cm wide strip in 0.454 kg units / 1609 m and also in g / 929 cm and also in 0.454 kg units / 3.785 1. To take the measurements too To facilitate this, the composition for the traffic markings was applied to glass plates. The observation of the underside of the glass plate showed that there were a relatively large number of color-free areas, from which it can be seen that

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24A Ί 546

the glass spheres had penetrated through the paint film so that these glass spheres were in direct contact with the Were substrate.

Example 2

Example 1 was made with a wet film thickness of 0.25 mm repeated. The results with different amounts of glass spheres are also plotted in FIG. Until tack-free Condition were measured for times as short as 30 seconds, although the paint itself took two minutes was tack free.

-Example 3

The paint from Example 1 was used.

This mass was based on an air-conditioned building Glass plates applied using a Bird applicator. The film had a wet thickness of 0.25 mm. A pre-weighed amount of Federal Specification TT-B-1325A, Type !, Class A) was applied to the wet film Sprinkle from a salt shaker with 19 holes with one Applied with a diameter of 0.139 mm. A quick and even distribution of the glass spheres was achieved.

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The times until the formation of traces ceased to exist were measured in accordance with ASTM D-711-67. The results were in Figure 1 plotted. Although the paint as such takes about 5 minutes to cease to form traces had, when using the system according to the invention, only times of 30 seconds and less were for the No trace formation measured.

Example 4

Example 3 was repeated except that the light reflective particulate material was a mixture of one part glass spheres and one part Ottawa sand, which was crystal grade. For different amounts of the small - Partial material times measured until the formation of traces ceases to exist and against the amount of small-part material plotted in FIG. In this experiment it should be noted that on wet roads, mixtures of glass spheres and spherical Sand are more visible than glass balls alone.

Example 5

Example 3 was repeated with the exception that Ottawa sand, crystal grade, was used as the particulate material became. The times determined for the elimination of the formation of traces were plotted in FIG. 2 for various amounts of sand.

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Example 6

Example 3 was repeated with the exception that as light-reflecting small-scale material a mixture of one part glass spheres and one part sea sand (Del Monte White Beach Sand (30 mesh)) was used. The times before the formation of traces ceased to exist were different Quantities of particulate material are determined and plotted against the quantity in FIG.

Example 7

Example 3 was repeated except that the light reflective particulate material was a mixture one part glass spheres and one part Ottawa sand was Federal Fine Grade. There were the times until the disappearance of the Trace formation is determined and plotted in FIG. 3 as a function of the content of small-sized material.

Example 8

Example 3 was repeated, with the exception that Ottawa sand, "Federal Fine Grade" was used. It became the times for the elimination of the formation of traces with different contents determined on small-part material and plotted against the amount of small-part material in FIG.

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24415A6

Example 9

Example 3 was repeated except that a mixture was used as the light-reflecting particulate material from one part glass spheres and one part Ottawa sand, crystal grade, was applied in two stages. First were the glass steps and then the sand applied. There are the times until the formation of traces ceases to exist for different ones Proportions of fine-grained material determined, and against the amount of fine-grained material in Figure 3 applied.

Examples 10 to 12

- Example 4 was repeated with the exception that the Film of the paint was applied in thicknesses of 0.28, 0.33 and 0.38 mm. As a small material, a Mixture of one part glass spheres and one part Ottawa sand, crystal grade used. It was the times for the disappearance the trace formation determined for different proportions of small-scale material for each film thickness, and in Figure 4 against the amount of the fine-grained material applied.

Example 13

Equal volumes of plastic balls, plastic and sand and glass balls were used as in Example 3 with similar Results plotted. Polystyrene,

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Vinyl chloride copolymers and vinyl acetate copolymers are used. No times for color uptake and trace formation under a minute were observed when These small-scale materials were applied in the same volume that 50 kg of glass spheres per kilometer is equivalent to.

Although the application of the traffic markings according to the invention has been explained in two stages above, this can also be done in another way. For example, one can use a mixture of pigmented fusible resin particles and applying a light reflective particulate material to the substrate and heating the resin particles melt. For this purpose, for example, open flames can be used, whereby the roadway and / or the fusible mixture is heated and a film is formed, by embedding the light-reflecting, small-scale material.

Except for the specifically mentioned coating compounds and light-reflecting Small-sized materials, known similar substances can also be used. The procedure too according to the invention can be modified in many ways.

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Claims (28)

Claims 1. Building rait a paved roadway and a traffic marking connected with it, thereby marked ichnet that contains the traffic marking (a) a pigmented dried coating composition containing an organic synthetic resin and as such has dried within about 6 minutes and is embedded in it, (b) at least one single layer of a light-reflecting small-sized material, the predominant being Percentage of particles of this material embedded at least half of their mass in the coating and has a diameter larger than the thickness of the coating film, and (c) the particles of light reflective particulate matter embedded in close proximity to one another so that they are less than about their average diameter apart. 2. Structure according to claim 1, characterized in that that the light-reflecting small-part material contains glass spheres. 509810/0359 3. Structure according to claim 1 or 2, characterized in that the light-reflective Small particle material contains a mixture of glass balls and spherical sand. 4. Structure according to claim 1, characterized in that that the light-reflecting particulate material contains spherical sand. 5. Structure according to claim 1, characterized in that that the light-reflecting small-part material is a mineral small-part material contains. 6. Structure according to claim 1, characterized in that that the particles of the light reflective small material are substantially in contact. 7. Building according to claim 6, characterized in that that the light-reflecting small-part material contains glass spheres. 8. Structure according to claim 6, characterized in that that the light-reflecting fine-grained material is a mixture of glass balls and sand contains. · 9. Building according to claim 6, characterized in that that the light-reflecting small-part material is a mineral small-part material contains. 50981 0/0359 10. Structure according to claim 6, characterized in that that the light-reflecting particulate material contains spherical sand. 11. Structure with a paved roadway and traffic marking that is adhered to it, characterized in that the traffic marking contains (A) a pigmented dried coating composition containing an organic synthetic resin and as such has dried tack-free within about 6 minutes after application, wherein this coating composition as a liquid film with a wet thickness of about 0.38 mm or less was applied and is embedded in the pigmented, dried coating mass (b) a light reflective particulate material, wherein (C) this light-reflecting small-particle material in the coating composition before it is dried in a Amount of at least about W weight per unit area A has been distributed, using the formula is applicable W «. £ - 'XVXG 2,598S ^Z
3 50981 0/0359 in the W = the weight of the light-reflecting small-sized material A = the unit area of the coating composition V = the volume of the central light reflective particle G = the specific gravity of the light reflecting particle S = the distance between the centers of light reflective particles that are uniform are distributed as a single layer in this coating, where S is about 2D or is less and D is the mean diameter of the light reflective particles. 12. Building according to claim 11, characterized in that that S is about 1.5D or less. 13. Structure according to claim 11, characterized. that S is about D or less. 14. Structure according to claim 7, characterized in that that the film has a wet thickness of about 0.25 mm or less. 15. Structure according to claim 13, characterized It is assumed that the film has a wet thickness of about 0.25 mm or less and the light reflective one small-scale material glass spheres, a mixture of glass spheres and spherical sand or spherical sand. 509810/0 359 16. A method for applying a traffic marking to a paved roadway, characterized in that that he (A) on the road surface a moist, uncured film of a pigmented coating composition, which is an organic Contains synthetic resin and as such within about 6 minutes after application non-tacky dries, applies, (b) at least one single layer of a light-reflecting, small-particle material on the moist film applies, with the majority of the particles of this material having a particle size such as that at least half of their mass in the movie '' - the coating mass is embedded and the diameter of the particles is larger than the thickness of the film and (c) the particulate material applies to the film in such a density that the individual particles are less than about a quarter of their average diameter apart. 17. The method according to claim 16, characterized in that that the coating mass dries out of itself in about 3 minutes or less after application and the fine-grained material in is applied at such a density that the individual particles in the coating film are substantially touch each other. 509810/0359 18. The method according to claim 16, characterized in that that the light-reflecting particulate material contains glass balls, spherical sand or mixtures thereof. 19. The method according to claim 17, characterized in that that the light-reflecting small-part material with a density of at least about 22 kg of small-sized material per km is applied to a 10 cm wide strip of the coating compound. 20. The method according to claim 18, characterized in that that the light-reflecting material with a density of at least about 28 kg of fine material per km on a 10 cm wide Strips of the coating compound is applied. 21. The method according to claim 20, characterized in that that the light-reflecting particulate material with a density of at least 44 kg of small-sized material per km is applied to a 10 cm wide strip of the coating compound. 22. The method according to claim 16, since d u r c h characterized that at least 0.83 kg of the light-reflecting particulate material per liter of Coating compound can be used. 509810/03 5 9 23, method according to claim 17, since through, -gek e η η ζ e i c h a e t that a coating mass that is used in less than about 1 minute dries tack-free. 24. Method of applying a Verkeiarsmarkierong on a paved roadway, d a d ii r c h g e mark that one refuses (a) on the pavement a damp uncured Film of a pigmented fiberziigsmas.se that Contains an organic synthetic resin and as such within about 6 minutes after application dries without sticking, applies, at least one single layer on the damp film a light-reflecting small-scale material, with the predominant portion of the particles of this material has a particle size such that at least half their mass is embedded in the film of the coating mass and the diameter of the particles but is greater than the thickness of the film and te) the light-reflecting, small-particle material in the excess mass, before it is dry, in an amount of at least about Έ weight per unit area A distributed ₉ where the formula applies ? _m . 2.598S 509810/0359 in the W = the weight of the light reflecting small part Materials A = the unit area of the coating composition V = the volume of the central light reflective particle G = the specific weight of the light reflective Particle S = »the distance between the centers of the light-reflecting particles, which are uniformly single-layered in this coating composition are distributed, where S is about 2D or less and D is the mean diameter which is light reflective particles. 25. The method according to claim 24, characterized It is estimated that S is about 1.5D or less. 26. The method according to claim 25, characterized in that that S is about D or less. 27. The method according to claim 26, d ad u r c h g ekennz It is assumed that the wet film has a thickness of about 0.38 mm or less, and that that light-reflecting small-scale material glass balls, a mixture of glass balls and spherical sand or spherical sand. 50981 0/0359 28. The method according to claim 27, characterized in that that the wet film has a thickness of about 0.25 mm or less. 509810/0359 Blank page