CA1303406C - Process and device for producing or renewing a horizontal marking on roads and horizontal marking produced in accordance with the process - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

During the laying of a marking line with the aid of at least one paint spray gun , profile particles are introduced by means of a profile particle dispenser in-to the marking composition and thereby enveloped all round by the latter. The dimension of the profile particles , which are preferably reflective beads, is greater than the layer thickness of the bare painted line, so that pro-file elevations are formed. Subsequently, reflective beads which also adhere to the profile elevations are scattered onto this profiled painted line , which beads thus ensure a good night visibility in wet conditions and when a water film is present, from which they project. The profile par-ticles can either be directly introduced into the jet of paints emerging from the paint spray gun or, subsequent to the application of a painted line, be scattered thereon and then completely covered with marking composition by means of renewed spraying of a thin film of paint.

Description

~3~3~

produc~d in accordance ~ith the process Fi~ o$ the inve~iorl The invention rel~tes to a process for producing or rene~ing a horizontal marking on roads, in particular of boundary, broken and ~arning lines, according to the pre-amble to Claim 1, to a road ~arking vehicle for carrying S out this process and to a horizontal ~arking produced ;n accordance ~ith this process.
pr i~r ~ he production of such horizontal mar~ings havin~
reflectiv~ beads embedded in the marking co~position has long been ~no~n and is for example described in EP-A-0 124 946~ These road markings are generally also easily recog-ni~able in the dark, ~hen the road is dry, due to the re-flective beads ~hich ar~ visible in the car headlights.
Ho~ever, they fulfil their task only unsatisfactorily or not at all ~hen it is raining or ~hen the ro~d is damp for othsr reasons, because the retroreflection from carriage~ay ~arkings ~hich are partly or completely covered by a film of ~ater, is greatly reduted or virtually no longer present.
The headliyht emitted by a vehicle is na~ely reflected spec-ularly by ehe ~ater surf~ce and not retroreflectively back to the driver of the vehicle. lt is known that retrore-fl~ction is understood as the reflection, largely indepen-dent of ehe entrance direttion, of the inci~ent li~ht by ~eans of part;cles acting re~ractively or sPeeularly.
The gre~t reduction in the visibi~it~ of the ~arkin~s when it is raining plays a deeisive role in night ~cci~ents.
Previous atte~pts to increase the niQht visibility i~portant for road safety ~hen it is ~et ~nd raining con-centr~te on profiling carri~ge~ay oarkings in ~ suitable ~y, so th~e ~levdtions projecting out fro~ the ~ter fil~
are designed ~ith surface are~s ~hich are orientated as steeply as possible to the incid~nt he~dlight. ln this ~ay, ~t th~se surface ~reas froQ ~hich the ~ater runs off, the specular reflection ;~ reduced and the retroreflection is - S~

: L3V3~ 6 inc e~sed.
for this purpose, it is essentially suggested in the previously ~entioned EP-A 0 12~ 946 to Lay as a painted line a thin layer ~arking ~hich continues after application to S re~ain plastically defor~able for a Long ~i~e, to scatter glass beads on the freshly painted line, a certain proportion thereof consisting of floatation be~ds which h3ve undergone a surface treat~ent to mini~i2e the depth to ~hich they sink in, and to defor~ the painted l;ne by pressing in a surface profile before the marking composition has co~pletely hard-ened. Such profilings, impre~nated after the ~arking has been applied, require ho~ever on the one hand a further, separate ~orking operation and can therefore only be produced ~ith considerable ~orking effort and on the other hand they are generally subject to a reLatively rapid abrasion or are levelled otf after a short time~
Similar disadvantages apply to kno~n thick-layer ~arkings ~hich can be provided ~ith thicker profiles than thin-layer ~arkings but ~hich have a hardening or pot time of in general only a fe~ ~inuses and are therefore no longer per~anently defDr~able even a short tine after laying.
Therefore, the profiling of a freshly laid thick-layer ~ark-ing ~ust be pressed in ;~ediately aft~r its ~pplication, this vork bein3 very delicate bec~luse of the only ~hort time Z5 of a fe~ ~inutes available.
It is also kno~n, when layin~ ~hick-layer ~arkings uhere it i~ a ques~ion of hot-e~truded ~r hard plas~ic com-positions ~hich are not sprayable but ~hich ~ust be applied for exaople ~ith a laying shoe, to shape profil~s in the for~ of studs or toric transverse ribs ~hich are arranged at a distance fro~ one ~nother.
A disadvantage coooon to ~ll hot-extruded or hard plastic co~positions is that devices r~quired for the;r laying are quite co~plic3ted and costly ~nd that the laying ~ork can only be perfor~ed slo~ly, 50 that daily output is lo~ co~pared to the r~pidly ~erforoed processin~ of spray-~ble ~ark;ng co~positions. Above all, that also applies to the l~ying of the toric profiles ~entioned, ~hich are ~3~341~;
produced inter~ittently and ~re~ on the one hand, easily detor~ed and rubbed off during snow clearing due to their relatively high and steep edges ~nd~ on the other h~nd, the~selves i~pede sno~ clearing because the sno~plough S pushes against the profile edges and cDn even be da~aged in the processu Furthermore, a satisfactory re-marking, that is the rene~al of a profiled thick-layer ~arking according to the same process by which it was produced is~ virtually i~possible, so that the maintenance of such markings is made difficult and more e~pensive. Due to the difficulties men-tioned and the high costs, hot-extruded or hard plastic ~arkings are only relatively seldom laid; some 90X to 95%
of all markings are thin-layer or ~edium layer markings ~hich can be produced quickly and cheapLy by spraying, but ~hich could not previously be provided ~ith prof;les in an efficient and effective ~anner.
In addition, it is kno~n to produce ~ilms having sur-face str~cture, ~or e~ampie pyr~mid-shaped, and ~o secure the~ on the road surface~ ~hich i~ however a~k~ard and ~stly.
To achieve good night visibility in ~et cond;tions poses, therefore, a proble~ ~hich has not yet been satisfac-torily solved, so that it has not yet been possible to in-crease road safety in darkness and ra;n by easily visible ~arking lines, as is desirable.
SummarY of the inver~ti~
~ he obj~ct ot the invention is to establish a process by ~hich, in a relatively cheap and si~ple ~anner, a horizon-t3l ~rking provided ~ith surface profiles is produced, hav-ing good nigh~ visibiLi~y also in ~et conditionsO a high stab-ility .~gainst abrasion and levelling off and, consequently, an econoaical service lite and can in addition be rene~ed ~ithout difficulties by re-dra~ing.
To achieve this object, the process according to the invention is ch~racterized by the f~atures indic~ted in P~t~nt Cl~
rhis process according to the invention ~kes it possible to produce the surface profiles during the laying of the p~inted line, in ~ joint ~orkin~ operation therefore, ~L3~3~
during ~hich the section to be processed is passed over only once ~ieh an appropriaeely equip~ed earking vehicle; in the course of this operation, s~all profiles completely covered ~ith ~arking co~position in the style of painted studs are S produced to uhich the subsequently scattered reflec~ive beads adhere, as small retroreflective beads. A profiled horizontal marking produced in this ~ay is particularly econo~ical because, it can constantly be dra~n as a nor~al thin-layer, or ~ediu~-layer marking by spraying as part of the custo~ary, usually applied marking ~ork without a second working operation being necessary for production of the sur-f~ce profiles. Thin-layer and medium-layer markings have ~et-film thicknesses of approxi~ately 0.3 to 1.5 ~m and shrink ~hen drying by 20Z to 40~, so that the dry-film thick-15 nesses are correspondingly less.
A further essential advantage consists in that theprofile particles projecting from the actual painted line due to their size are coopletely enveloped by ~arking com-position and are, therefore, stably anchored in the paint~d line so that the danger of these profile particl~s being ripPed out by the traffic r~nning over them i~ greatly reducedr Further~ore, they do not i~pede snow clearing because the slo~plough is alYays supported on a large number o~ profiles and thQrefore al~ays ~orks in the tangential plane to the vertexes of the profiles ~ithout running against profile edges. For this reason, the d3nger of the profiles for their part being damaged during sno~ clearing and th~ profile particles being pressed aut is only very slight.
. A further advantage consists in the p~ssibility of ~orn profil2d ~arkings being rene~ed readily by re-drawing, which ~as not readily possib~e in the c3se of the previously kno~n prsfi~ed ~rkings.
If, prefer~bly, ~ppropriately di~ænsioneJ reflective be~ds or oeher reflecting, at ~east ~pproxi~ately spherical, particles are used ~s profile p~rtieles, there is the fur-ther advantage that the areas of th~ profile particles pro-jecting fro~ the painted line the~selves contribute to the ret~ection and retroreflectlon, a~ s~on as the paint layers adhering to these ~reas have been rubbed off by the traffic.
Such a hori~ontal marking according to the invention there-fore also retains i$s good night visib;lity ;n we~ condi-tions ~hen it is considerably worn, as Long as sufticientprn~ile particles are still present.
As a resuLt of ~he invention, therefore, a night visibility of carriage~ay ~arkings in rainy ~eather ;s achieved ~hich is signi~icantly better and longer lasting than ~as previously possible; that applies particularly to carriageway boundary lines as ~ell as t~ broken and warn;ng lines, the recognition of ~hich is especially important for road safety.
The process according to ~he invention may be car-ried out ;n such a way that the profile par~icles are laidsi~ultaneously ~ith the spraying of the marking composition in that they ~re scattered or shot into the pointed jet of paint or in the direct vicinity of ~he point of impingement of the jet. It is, ho~ever, also possible to proceed in 20 such a ~ay that firstly a painted line is sprayed, im~edi- ¦
ately a~er~ards the profile particles are scattered thereon and ~hen ~arking composition is once again applied in order to completely envelop the profile particles.
A road mar~ing vehicle for carrying out the process according to the invention is characterized by the features indicated in Patent Clai~ 8.
Expedient developments of the process and o~ the device result fro~ the dependent pa~ent clains.
B~ief ~riPtion o~ the dxawinqs ~n The inven~ion is explained in ~ore detail ~ith the aid of dr~ings of diagr~atically illustrated exe~Plary ~bodi~ents. They sho~:
Figure 1 a first exa~ple of a ~arking vehicle, only indicated, having a paint spray gun into ~hose jet profile particles are introduced.
Figure 2 a second ex3Mple having t~o paint spray guns spraying one p3inted line, ~hich guns are 2rranged transversely to the direction of travel next to one another.
Figure 3 a third ~xa~ple, in ~hich t~o paint spr~y ~3~1~6 guns producing a painted line are arranged one behind the other in the direction of travel.
Figure 4 a fourth example of a marking vehicle, with which profile particles are scattered onto the ini-tially laid painted line and then covered with markingcomposition, and Figures 5 and 5b a diagrammatic section through a hori~ontal marking according to the invention, provided ~ith surface profiles, before and after the scattering of small reflective beads.
PescriP~ion of ~?re~err~d em~p~i en~
According to Figure 1~ a paint spray gun 2, a pro-file particle dispenser 4 and behind them, seen in the di-rection of travel, a bead scatterer 7 are arranged on the marking vehicle 1, only diagrammatically indicated, which moves in the direction of the arrow. The paint spray gun 2 sprays marking composition 3 in a known manner onto the road surface S in the form of a fan-shaped jet transverse to the direction of travel. The prof;le particle dispenser 4, mounted in the immediate vicinity of the paint spray gun 2, is directed onto the somewhat inclined jet of paint so that profile particles 5 enter the sprayed ~arking composition 3 before the jet impinges upon the road surface S. In this way, the profile par~icles 5 are covered completely with marking composition.
The m;ni~u~ dimension of the profile particles 5, reflective bea~s in the example considered is greater than the dry-film thickness or the la~er thickness of the actual pa;nted line. Therefore, as illustrated in Figure 5a, the horizontal marking 6 produced has surface profiles ~ in the for~ of painted studs, ~hich are formed by means of the pro-jecting areas of the profile particles S completely covered by ~ark;ng composition. Subsequently, reflective beads 8 are scattered onto the still fresh profiled painted line 6 by ~eans of the bead scatterer 7. The finished painted line 10 thus obtained, illustrated in Figure Sb, has therefore surface profiles 9 provided with reflective beads 8~
These scattered reflective beads 8 ~ay be a custo-mary mixture of nor~al reflective beads whose diameter is ~3~39tO~
bet~een 0.05 and 0.8 mm and ~hich are therefore smaller than the profile particles 5.
Ho~ever, in order to increase the effect of the re-troreflection bet~een the profile elevations, the scattered reflective beads can advantageously also contain large re-flective beads having a dia~eter of at least 0.8 mm, prefer-ably of approximately 1 to 2 mm, which naturally improve the visibility of the marking particularly well. ~hilst such large reflective beads would be ripped out of a level mark-ing relatively quickly by the traffic running over them, inthe case of a marking according to the present invention, they are extensively protected by the neighbouring profile elevations, since the tyres of the vehicles running over them are essentially supported on the profile elevations and do not stress, or stress only insignificantly, the reflective beads lying bet~een them. In order that this protective effect acts well, the profile elevations in the middle should be of a height such that they project somewhat from the large beads which ~ie between them. In the case of such a marking, on the one hand the normal reflective beads which adhere to the profile elevations and on the other hand the large re-flective beads located between the profile elevations retro-flect abo~e all.
The marking composit;on used is preferably a simple and efficien~ to lay thin-Layer or else medium-layer marking, ~hose solids are dissolved for the application in a solvent and ~hich, ;n the case of single-component paints, harden exclusively by evaporation of the solvent and in the case of multi-component paints harden by evaporation of the solvent as well as by chemical drying~ In th;s case, the wet-f;lm thicknesses a~ount to approximately 0.3 mm to 1.5 mm~ which corresponds to dry-film thicknesses of approxi~ately 0.2 mm to approximately 0.8-1.2 m~.
The prof;le particles 5 are at least 0.6 mm larger than the dry-film thickness and can, dependent on paint-layer thic~ness~ have diameters betueen approx;ma~ely 1 mm and 6 m~, these sizes naturally being selected in such a way that the prof;le particles, whilst being anchored as stably ~3~39~0q~
as possible in the painted line, have a sufficient profile height. This diameter range is expedient for roads which are regularly cleared of snow in the winter and therefore profiles ~hich are too high should not be present. In special cases, in particular in regions ~here snow clearing does not take place or is not necessary, profile particles ~ith diameters up to a ~aximum of R mm or even 10 mm can also be used.
In the example considered, the dry-film thickness of the bare painted line at the places ~here only marking composition 3 and no profile particles are present amounts to approximately 1 m~ and the diameter of the profile par-ticles amounts to approximately 3 mm, so that the profile elevations 9 covered with paint and small reflective beads 8 project by approximately 2 to 3 ~m from the actual painted line. Preferably, under the separate reflective beads 8 there are also large reflective beads having dia-meters of approximately 1 - 2 mm which li2 protected be-t~een profile elevations and which further increase retro-reflection. The maximu~ overall layer thickness of the finished line 10, measured at the profile elevations, is then approximately 3 to 4 mm Inst~ad of a thin-layer or medium~layer marking, a sprayable thick-layer marking can also be used.
The profile elevations, from ~hich the ~ater runs off~
which are present a~ the positions of the profile particles 5, are virtually never completely a~ash ~ith a fil~ of water in rainy ~eather and therefore guarantee a good night visi-bility even ~hen it je raining; in addition, they prevent the -for~ation of a continuous ~ater film and have the con-stant effect of dispersing the ~ater running off. There-~ore, the profile elevations 9 covered with small glass beads 8 reflect even in rainy ~eather and nake the marking easily v;sible by means of retroreflection. Especially in the case of carriage~ay boundary l;nes ~hich are after all located outside the carriage~ay lane and are therefore wet and covered ~ith ~ater usually for some tine in rainy ~eather, this night visibility is particularly essential ~3~3~

and contributes decisively to road safety. Due to the only relatively low profile heights, on the other hand, the pro-cess in accordance with the invention is also suitable for the production of centre lines, broken lines and warning lines.
If reflective beads are preferably used as profile particles, that has the additional advantage that the mark-ing fulfils its task at night and in ~et conditions even after the paint has been rubbed off from the surface profiles 9~ beca~se from then on the exposed areas of the profile particles themselves reflect.
In order to improve the skid resistance of the marking, it is reco~mended that the profile particles used comprise at least in part irregularly shaped mineral particles, for ex-ample chippingst gravel, broken glass or the like, which fur-thermore adhere particularly firmly to the marking composi-tion due to their angular shape and thus increase the dura-bility of the profiles, these particles being preferably mixed with reflective beads. Naturally, particles of other suitable mater;al, for example of plastic, and of any shape, for example in the form of ellipsoids or polyhedras, can also be used~
In the example according to Figure 1, the profile particle dispenser 4, ~hich is a pneumatic spray gun, is al;gned at a slight angle to the likewise slightly inclined jet of the paint spray gun 2, so that the profile particles 5 are shot into this jet at an acute angle. The dispenser 4 can also be a simple scattering device and in this case it is installed Yert;cally, above the inclined jet, so that the profile particles fall vertically onto and into this jet.
In ~he example according to Figure 2, the painted line 6 is produced ~ith the aid of t~o paint spray guns 2a and 2b arranged at an angle to each other and next to each oth~r ;tranversely to the direction of travel, each deliver-ing a fan-shaped jet 3a and 3b. Both fan-shaped je~s lie at least approximately in a Plane and overlap each other. The profile particle dispenser 4 is located in the ~iddle be-t~een the t~o paint spray guns and scatters or` shoots the ~L3~3~
profile particles 5 between the t~o fan-shaped jets of paint 3a and 3b into the marking composition, before the latter im-pinges upon the road surface S. At a distance behind this arrangement is the bead scatterer 7, for applying small re-flective beads 8. The painted lines 6 and 10, diagrammati-cally illustrated in Figures Sa and 5b, are produced in turn.
The t~o jets of paint can also impinge contiguously on the road surface without overlapping, each producing half the line width.
In the example according to Figure 3, the marking vehicle, not illustrated in more detail, in turn has, for the drawing of a marking line, two pain~ spray guns 2a and 2b, positioned at an angle to each other, which are, in th;s case, positioned one behind the other in the direction of travel in such a way tha~ the two fan-shaped jets of paint 3a and 3b impinge upon the road surface S at least approxi-mately in a common line. A profile particle dispenser 4 in the form of a pneumatic gun is arranged inclined in front of the two paint spray guns in the direction of travel in such a way that the expelled profile particles 5 are thro~n at a certain angle against and through the front jet of paint 3b so that they are entrained partly by the front jet of paint 3b, partly by the rear jet of paint 3a or caught bet~een the t~o jets of paint. Of course, the profile particle dispen-ser 4 can also be arranged in the middle between the t~opaint spray guns 2a and 2b and be positioned essentially vertically so that the expelled profile particles arrive directly bet~een the t~o jets of paint. In this case too, a bead scatterer 7 for the applic~tion of small reflective beads 8 on the painted line 6 is provided so that the pro-filed painted line lU coated with reflective beads is again produced.
Instead of mixing the profile part;cles directly ~ith the marking composition emerging fro~ the paint spray ~uns, the procedure as sho~n in Figure 4 can also be follo~ed. In this case, a first paint spray gun 11 is initially used to spray a painted line, ~hose layer thickness is somewhat less than corresponds to the final lay~r thickness desired.

~3~3~1Q6 Using a profile particle dispenser 12 installed behind this paint spray gun 11, profile particles 5 are then scattered on the fresh painted line and subsequently marking composi-tion 3 is again sprayed, by means of a second sPray gun 13, S onto the painted line coated with profile.part;cles 5 so that the profile particles are completely covered with a film of paint. finally, reflective beads 8, which prefer-ably also include the large reflective beads mentioned, are in turn scattered~ Instead of drawing the painted line with only one paint spray gun 11, two paint spray guns, as in accordance with Figure 2 or 3, can also be used for this purpose.
All devices mentioned for the production of the complete, profiled marking are installed on a common marking vehicle which, whilst passing over the section to be proces-sed once, permits this marking to be produced or renewed rapidly and economically~

Claims (11)

1. Process for producing or renewing a horizontal marking on roads, in particular of boundary lines, broken lines and warning lines, whereby a painted line is applied by spraying a marking composition and subsequently reflective beads are scattered on the still fresh painted line, characterized in that, before the reflective beads are scattered thereon, profile particles, whose minimum dimension is greater than the dry film thickness of the newly applied painted line are introduced into the painted line and are completely enveloped in marking composition, so that a marking having profile elevations is produced.

2. Process according to Claim 1, characterized in that, during the application of the painted line, profile particles are introduced into the jet of the sprayed marking composition or are scattered in the immediate vicinity of the impingement point of the jet, two paint spray guns being used which simultaneously draw one painted line and which produce fan-shaped jets which impinge upon the road surface at least approximately in a common line, the profile particles being preferably introduced into the marking composition between the two jets.

3. Process according to Claim 1, characterized in that first a painted line is sprayed, in that the profile particles are then applied to the still fresh painted line, and in that subsequently, before the reflective beads are scattered, the painted line coated with profile particles is again sprayed with marking composition so that the profile particles are covered with a paint film.

4. Process according to any one of Claims 1 to 3, characterized in that profile particles are used whose minimum dimension is greater than the dry film thickness of the applied painted line by at least 0.6 mm.

5. Process according to any one of Claims 1 to 3, characterized in that, the profile particles used comprise at least in part particles having an at least approximately spherical shape, preferably reflective beads.

6. Process according to any one of Claims 1 to 3, characterized in that, the profile particles used comprise at least in part irregularly shaped particles, in particular chippings, gravel, broken glass or the like, preferably mixed with glass beads.

7. Process according to any one of Claims 1 to 3, characterized in that, reflective beads with a diameter of at least 0.8 mm, preferably 1 to 2 mm, are at least in part used when scattering the reflective beads on the painted line which is provided with profile elevations.

8. Marking vehicle for carrying out the process according to Claim 1, having at least one paint spray gun and at least one reflective bead scatterer arranged behind the gun in the direction of travel, characterized in that, a profile particle dispenser (4, 12) is arranged in front of the reflective bead scatterer (7).

9. Marking vehicle according to Claim 8, characterized in that, at least two paint spray guns (2a, 2b) for drawing a painted line are provided which deliver fan-shaped jets and are aligned such that their jets (3a, 3b) impinge upon the road surface at least approximately in a common line, the two paint spray guns (2a, 2b) being arranged transversely to the direction of travel of the marking vehicle or one behind the other, and in that the profile particle dispenser (4) is aligned such that the emerging profile particles (5) at least for the most part arrive in the marking composition between the two fan-shaped jets, or impinge on a fan-shaped jet at an acute angle.

10. Marking vehicle according to Claim 8, characterized in that the profile particle dispenser (12), and behind it a further paint spray gun (13), are arranged behind, in the direction of travel, at least one of the paint spray guns (11) drawing the marking.

11. Horizontal marking produced in accordance with the process according to Claim 1, having reflecting profile elevations covered with marking composition.