CA1181296A

CA1181296A - Method and apparatus for applying a pattern to a continuously advancing web of material

Info

Publication number: CA1181296A
Application number: CA000408043A
Authority: CA
Inventors: Heinz Gruber; Johannes Kutz; Manfred Moser
Original assignee: Eduard Kuesters Maschinenfabrik GmbH and Co KG
Current assignee: Eduard Kuesters Maschinenfabrik GmbH and Co KG
Priority date: 1981-08-18
Filing date: 1982-07-26
Publication date: 1985-01-22
Also published as: GB2107613B; GB2107613A; AU8477882A; US4463467A; AU548027B2

Abstract

ABSTRACT OF THE DISCLOSURE

The invention relates to a method and apparatus for applying patterns to a continuously advancing web of material including using a foam generating device, and a foam applicator, by means of which the foam can be applied to the web of material in layer form over the width of the web of material, and a device for making patterns in the layer. At least one motion generator is arranged above the w? of material, and an attack element is connected thereto for making the foam layer uneven in places or traces. The invention provide an improved method an apparatus for making patterns which are much more diversified and precise compared to those presently found in the art.

Description

29~

BACKGROUND OF THE INVENTION
This invention relates to the application of patterns to a continuously advancing web of material. More particularly, it relates to an improved method and apparatus for carrying out such an application using foam.
DE-AS 22 14 377 teaches methods of the general type to which the present invention relates. The pattern obtained depends on the treatment agents presen~ in the layer. ~lso, different foams may be present in the layer either on top of each other or side by side. A pattern can be obtained by selectively wiping the layer to a different height in selected places. Treatment always occurs because of the presence of the layer, i.e. a supply of treatment medium in a rather uniform amount applied over the area.
The present invention seeks to develop an improved method of the general type described above as well as an apparatus which functions in such a manner that a novel and far-reaching modification of the resulting pattern is possible.
SUMMARY OF THE INVENTION
The present invention provides a method for applying patterns to a continuously advancing web of material with a treatment medium contained in a foam, in which the foam is present in a layer before or after being transferred to the web, comprising making the foam uneven ln the layer in places or traces.
In a preferred embodiment of the lnvention, the pattern i8 a co].or pattern, in which one or more clyeing liquors are contained in the foam. Beaides the dye:Lng liquors, however, resist agents which influence the fie:Lcl and the structure of the web oE material, are applled in the form of foam. These resist agents are also important as treatment agents.

2~E;

The web of material may be either a textile web material, a bonded woven fabric, a paper web, or a web of plastic.
The invention includes basically two embodiments. In the first embodiment, the unevenness is created in a layer in which the foam is made available before it is transferred to the web.
In the second embodiment, the unevenness is accomplished as soon as the ~oam has been transferred to the web. Depending Otl the composition and the properties of the ~oam and the structure of the web, the foam w:Lll remain on the sur~ace of the web for a certain amount of time as a separate layer wlthout substantially penetrating the web. In this phase of the operation where the foam has been drawn or worked into the web, the formation oE the pattern in the web begins practically immediately. In the case of dyeing, the absorption, and substantial influence on the pattern is no longer possible.
This unevenness is made in places or traces. In effect this can be described as "writing in foam." Places or traces are point-like or line-like zones of dimensions substantially smaller than the width of the web of material.
~ith a width of the web of 2 to 5 m.9 these zones have a diameter or width down to the width of a finger or pencil. However, somewhat larger dimensions are also included in the present invention, i.e. such dimensions are used for obtaining patterns on the customary substrates such as textile goods for apparel, decoration and rugs.
The unevenness obtained in the ~oam layer in places or traces is transEerred to the web of material and manifests itselE in a pattern. This ls Eavored by the fact that the foam has a much lesser or pract.Lcally no mobility when compared to a l:Lquid; this of course, dependitlg on its Eoam number, i.e.
the volume ratio between the llquid forming the Eoam and the ~oam. The higher 9~

the foam is blown up, the lesser is its mobility and consequently the patterns which have been generated on the "surface" on the web are more exactly maintained.
Since a liquid would penetrate into the web of material immediately, such as in the case of textile goods, there would be no opportunity to apply a pattern comparable to the present invention.
The patterns, attainable with the present invention uslng the appli-cation of foam, are distlnguished by a substantially greater conciseness than w:Lth pattern appllcation of liquld which is known from DE-OS 23 61 517.
The unevenness can be achieved by displacement of the foam. Here, the displaced amount of foam accumulates in the edges of the displacement reg:ion causing an increased supply of treatment medium, which manifests itself, by dyeing such that the color appears particularly deep at the edge of the dis-placement region thereby accentuating the latter. This effect is lacking if the foam is removed.
Conversely, a gaseous, liquid or solid treatment medium can be added which treats the foam, i.e. makes it collapse around it locally as is basically known from DE-AS 22 14 377. Onemay also obtain an additional treatment effect on the web of material besides the treatment effects obtained by the foam and its components.
The invention also seeks to provide an apparatus for implementing the method of the present invention. The inventlon provlds an apparatus for applyingpattern.s to a continuously advnnclng web of materlal comprising a foam generating clevice and a Eoam applicator, by means of which the foam can be applied to the web of material in layer form over the width Oe the web of mater3.al, and a device for making patterns in the :Layer, the improvement compris:lng:
a) at least one motion generator arranged above the web of material;
and b~ an attack element connected thereto for making the foam layer uneven in places or traces.
The attack element modifies the foam layer and applies therein the unevenness in places or traces. In one process, the attack element ls moved by a motion generator in order to generate a pattern in the foam layer passing by the attack element. It is also wlthln the scope oE the present lnvention for the motlon generator not to generate any motion. For instance the attack elements may be held still so that a stripe-like pattern is obtained ln the foam layer. Normally, however, the attack elements will also contain crosswlse motion components ~o that a two-dimensional pattern ls brought about in the foam layer.
The attack elements can develop their effect down to the bottom of the foam layer, but the patterns of the present invention can also be obtained when the foam layer is made uneven only over part of its height in places or traces.
The motion generators can either be common to several attack elements, or a separate motion generator may be assigned to each attack elemen-t.
In the first-mentioned case a number of attack elements attached to a common support, iE designed in the same manner, execute the same motion and therefore generate a pattern with a sort of rapport. In the second embodiment there is provided a possibility Eor generating an entirely random pattern, in that all motion generators provided transmit motions to their associated attack elements independent:Ly of each other.
An important embocl:Lment oE the present lnvention :Ls one ln whlch the use of the attack elements ls separate:Ly controlled. Because at least one of the attack elements can be turned off or, in the case of a mechanical attack element can be lifted ofE the surface, it can be put out of operation as desired, thereby giving a further modification to the pattern.
Various types of attack elements are described in the invention. A
rod or strip-like member acts like a kind of pencîl or finger which extends entirely or partially into the foam layer on the web. Such an attack element can be either rigid or flexible. In particular, a flexible element may touch and rub on the web.
A preferred attack element is a drawing element. The drawing element can be a thlck rope or chain which executes, due to its mobility relative to the motlon generator, lndependent motions which are reflected in corresponding tracks irl the foam layer. The drawing member itself, if a chain is involved, may also act upon the foam layer. However, an additional pendulum body which moves in the foam layer can also be attached at the free end. In one embodiment, the pendulum body rolls or slides back and forth on the web of material.
In a sphere, the generated pattern track is relatively narrow with slowly changing edges.
When a pendulum body has at least one flat surface, the track is wider and is cleared completely of foam since the pendulum body rests flat on its plane surface.
The above-mentioned elements displace the foam to the side. The attack element, however, may also be a suction trunk in communication with a suction line, thereby drawing foam from the foam layer in places or traces.
Instead oE removing the foam :Ln places or traces, something can also be adcled to such zones. Thls can be accompl-lshed wlth a spraying device whereby a narrow:Ly bounded ~et of a gaseous liquid or powder-shapQd treatment medium can be directed towarcls the foam. Lt 1~ not wlthin the confines oE the present lnvention to spray the ent:Lre Eoam surEace uniformly, but rather a narrow 2~

limitation of the jet is used whereby "writing in foam" is possible.
The attack element may also be a light source, by means of which a narrowly defined light or infrared beam can be directed onto the foam. Due to the temperature rise which occurs in the incidence region of the beam in the foam, the foam is decomposed or otherwise changed such that a pattern is obtained.
More partlcularly the invention provides a method Eor applying a pattern to a continuously advancing web with a treatment medium contained in a foam comprising:
a) applying the foam to an element rotating about an axis extending transversely to the web;
b) generating a patterned foam layer on the element;
c) wiping the foam off from the revolving element with a wiper blade and transferring it by the wiper blade to the web of material which passes underneath without making contact; and d~ controlling the forward velocity of the web of material and the speed of rotation of the revolving element to obtain a desired pattern effect onthe web, a device for applying patterns to a continuously advancing web with a foam containing treatment medium, comprising:
means revolving about an axis extending transversely to the web;
means arranged above the revolving element for generating a patterned foam layer on the revolving element;
a wiper extending transversely over the web, havlng an upper edge and a lower edge, said upper edge rest:Lng agalnst the s-lde of said revolvlng meansdescencllng durlng rotatlon for strlpplng the foam layer from the revolving element, and said :Lower edge dlsposed above the web of materlal and parallel thereto; and means Eor controlling the forward velocity of the web of material and the speed of rotation of the revolving element in a selectable mutual relation-ship.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 to 3 are side views, transverse to the web, of three basic embodiments of devlces according to the present invention, in which the uneven-ness of the foam layer ls accomplished before it is applled onto the web.
Figure ~ is a corresponding view of an embodiment in which the uneven-ness of the foam layer is accornplished after it is applled to the web.
Figures S and 6 are views in the longitudinal direction of the web of different embodiments of the present invention.
Figure 7 is a cross section along the line VII-VII in Figure 6.
Figure 8 is a cross section along the line VIII-VIII in Figure 6.
Figures 9 and lO are a cross section through the support designed as a revolving tube ~ith elongated elements.
Figure 11 is a perspective view of a motion generator with an element which is movable to all sides.
Figure 12 is a cross section through an arrangement with suction trunks.
Figure 13 is a view of a motlon generator with a spraying device arranged thereon.
Figure 1~ is a vlew oE a motlon generator with a light source with collimator arranged thereon.
Figures 15 and 16 are perspective vlews of practlcal embodiments of the inventl.on with a support extending crosswise over the web and elements.
Figure 17 ls a control for an arrangement according to Figures 15 and 16.

9~

Figure 18 is a perspective schematic view of a further embodiment of the present invention utilizing a roller.
Figure 19 is a similar view of an embodiment with a rotating belt.
In Figure 1, a web oE material 1 is qhown which is moved forward in the direction of the arrow 2 on a substantially horizontal guide via rolls or the like (not shown). Across the width of the web of material, a running-off surface 3 in the form of an elongated rectangular plate with a closed plane surface i5 provided, on whlch foam in the form of a layer can be placed in the upper region at ~ by a foam applicator (not shown). ~he surface of the plate 3 forms the "area" 5 on which the foam in the form of the layer 6 slides down over the plate 3, in the direction of the arrow 7 under the action of gravity, and is transferred from the lower edge 8 of the plate to the web 1.
Above the plate 3, a motion generator 10 is arranged which is merely indicated by a rectangle and from which an attack element 12 in the form of a rod protrudes toward the plate 3. The rod extends almost to the plate 3, but can also end a predetermined distance above it. In any case it engages the foam layer 6 and displaces the foam and makes it uneven at this point. The motion generator 10 imparts to the attack element 12 motions which extend perpendicular to the plane of the drawing, i.e. transversely to the web 1 and in the direction of motion 7 of the foam layer 6, there may in addition, be a component parallel to the direction 7.
As will be Eurther explained in connectlon wlth Figures 5 and 6, several motion generators 10, each wlth an assoclatecl attack element 12 may be provided side by side transversely to the web 1, or several attack e:Lements 12 arranged side by slde may be mounted on one motion generator 10.
Figure 1 shows that the arrangement oE the mot:lon generators and attack elements can also be staggered in the direction 7 of the foam movement, as is indicated by the second motion generator la' with the attack element 12'.
In the embodiment of Figure 2, che "area" 5 is formed by the upper section, advancing approximately horizontally in the direction of the arrow 13, of a belt 14 which is gulded endlessly about two drums 15 and 16 and on which the Eoam ls placed at 4 ln the form of a layer 6, and wlth whi.ch the web of materlal 1 ls brought together at point 17, a polnt followlng the attack polnt o the attack element 12. The web of materlal 1 is looped over the drum 16 in the manner shown in Figure 2, by a certain looping angle 18 whlch is approxl~
mately 90 ln the illustrated embodiment, accepting ln the process the patterned foam whlch ls enclosed between the web of materlal 1 and the surface of the belt 14.
In the embodiment of Figure 3, the "area" 5 is formed by the surface of a drum 20, which revolves in the direction of the arrow 21. After passing the attack element 12 and the pattern-making taking place there, the foam layer 6 applied at 4 is enclosed between the surface of the web 1 which is runnlng onto the clrcumference of the drum 20 approximately at 22 and ls accepted by the web 1 during the passage through the looping angle 18 which is again about soG in the example.
In Figure 4, a web of materlal 1 is shown whlch moves forward on a substantlally horlzontal guide via rolls or the like (not shown) ln the direction of the arrow 2. At 4, foam ln the form of a layer L8 p:Laced across the wldth of the web of materlal by a foam appl:lcator,(not shown).
Above the web of materlal 3, a motion generator :L0 is arranged whlch ia merely indicated by a rectangle and engages the foam layer 6 :Ln the same manner as ls the case in Figures 1 to 3, and displaces the foam and makes lt %~

uneven at the point in question. Similarly, several motion generators 10 with associated attack elements 12 can be provided side byside transversely to the web 1 also in this embodiment, or several attack elements 12, arranged side by side, can be mounted on one motion generator 10, and the arrangement of the motion generators and attack elements can also be staggered in the direction 2 of the web motion, as is indicated by the second mot:Lon generator 10' with the attack element 12'.
In Figure S, the web of materlal 1 runs perpendlcular:Ly to the plane of the drawlng. Several motlon generators 10, each wlth an assoclated attack element 12, are arranged side by side. Since a separate attac~ element is associated with each motion generator, all attack elements 12 can execute motions different Erom each other. For example, each may be controlled by a random motion generator. The motion is executed as indicated in Figure 11 in the direction of the arrow 23 transverse to the web of material as well as in the direction of arrow 24, in the longitudinal direction of the web of material, so that any desired pattern can be brought about in the plane of the web of material 1 through the superposition of the two motions.
In Figure 6, a beam 25 in the form of a square hollow section is provided across the width of the web of material 1, at the ends of which a motion generator 100 is attached for generating a motlon of the beam going back and forth in the direction of the arrow 26 transverse to the web of materlal 1, and on the other sicle, a motion generator 200, which causes a reciprocating rotary motion of the beam 25 in the direction of the arrow 27. The most varied patterns are produced by the controlled superpositlon oE the two motions. In addition, a Eurther pattern possiblllty ls created here when lnclivldual attack elements 12 are attached to pneumatlc piston/cylinder unlts 23 whlch permit ~8~Z9~;

lifting the attack elements off the Eoam layer 6 50 that they do or do not generate a pattern, as desired. At the points marked by ~he arrow 29, the attack elements 12 are not in engagement. The pneumatic piston/cylinder units 28 are coupled to a common pneumatic feed line and can be actuated by electric-ally controlled valves as desired. Instead of the pneumatic piston/cylinder unlts 28, corresponding magnetic actuators can be provided.
In the cross sectional vlew of Figure 7, the attack elements 12 provlded iTI the leEt ha:Lf of Figure 6 are shown ln detall. These are tube or hose sections 31 which are mountecl on the piston rod 30 of the piston/cyl:Lnder unit 28 and which are, if the piston rod 30 is pulled in, located with their lower end, in the manner seen in Figure 7, at a distance above the foam layer 6.
The lower ends dip into the foam layer 6 if the piston rod is extended, and displace the foam at this point. The tube or hose section 31 is shown as open at the bottom but it may, of course, also be closed. Likewise it is possible to attach to the lower end still larger displacement or wiper bodies which enlarge the action range of the attack element 12 and produce wider places or traces at which the foam has been displaced.
Figure 8 shows another embodiment of the attack element 12 in which, instead of the relatively stiff tube or hose section 31, a completely flexible chain 32 is fastened to the piston rod 30. In the illustrated embodiment, this chain has a sphere 33 at the other end which, with the piston rod 30 pulled in, is suspended above the Eoam layer 6 but extends, wlth the plston rocl 30 pulled out, lnto the foam layer 6 ln the manner shown. This makes the foam layer uneven. The dlfference from the embodiment :Ln Flgure 7 is that ln Flgure 7 the track of the attack element is uniform over a certain width, while the sphere procluces a trace with the lowest point and ~miform rise toward the eclges in the ~18~Z~

foam layer 6. The embodiment according to Figure 8 can also be developed so that the balls 33 rest on the web of material 1; then, the sphere 33 can roll back and forth on the surface of the web of material 1. Instead of a sphere, a pendulum body~ 34, bounded by flat surfaces, in the form of a cube or the like whlch generates tracks corresponding to the embodiment according to Figure 7 may also be used.
I~ -the ~oam layer 6 contains different, especially diEferently colored, foams on top of each other or side by side, an additional pattern effect is obtained in that the attack elements 12 drag foam from one region into an adjacent region, so that traces of the first foam are found in the latter, and cooperate in forming the pattern.
~ n Figure 9, a further possible embodiment is shown, in which the beam 25 is designed as a tube which extends across the web 1 and is driven, similarly as in Figure 6, by motion generators 100 and 200, and in which piston/
cylinder units 28' are arranged which carry at the end of their piston rod, via a resilient connecting piece 35, wiper or displacement bodies 36 which engage the foam layer 6 upon rotation, sliding in the process, on the surface 5, bending the connecting members 35, and displacing the foam. The piston/cylinder units 28' may be distributed over the circumference of the carrier 25 if the carrier is revolved continuously in one direction; if the carrier 25 executes a back and forth movement, the piston/cylinder units would be arranged predom-inantly in an ang~llar range fac:ing the foam layer.
In Flgure 10, a correspondlng embodlment ls shown which is used for maklng a foam layer 6 which is a:Lready on the web :L, uneven.
In Figure 12, an embodiment ln whlch a suctlon tube extending cross-wlse to the foam layer is provlded wlth suction trunks 39 distrlbuted over the Z~6 width of the web of material 1 is shown. Suction trunks 39 extend into the foam layer 6 and draw off the foam in places or traces. There, the foam is therefore not displaced into the adjoining regions as in the previous embodiments, but is actually removed from the foam layer 6. Attack elements in the form of suction trunks 39 can, of course, also be provided with individual motion generators 10 as in Figures 1 to 4.
In the e~bodiment accordlng to Figure 13, a spraying device 44 ls connected to a motLon generator 10; this devlce comprises a spraying nozzle 40 from whlch a largely parallel, collimated jet 41 of a gaseous, liquid or powder-shaped treatment medium can be aimed toward the foam layer 6. The treatment medium can make the foam collapse in traces as indicated at 42, or cause treat-ment effects in places or traces which act, in addition to the effect of the foam layer 6, on the web of material 1. In the illustrated embodiment, the motion generator 10 is stationary and the direction oE the jet of the nozzle 40 can be controlled or swung randomly in all directions in the same manner as is indicated in Figure 11.
In the embodiment of ~igure 14, a light source 44 is connected to the motion generator 10 and comprises a collimater 46 which directs a parallel lightbeam 47 toward the foam layer 6 which breaks down locally by the heating effect as indicated by 48. Instead of the light source 45 with collimator 46, a laser arrangement can also be provided which brings about higher energy density. Also in the embodiment accordlng to Figure 4, the direction oE the ~et 47 can be changed by the motion generator 10 ln the sense of Fig~lre 11.
In the last-mentloned embodlments, the nozzle 40 wl~h the Jet 41 and the collimator 46 with the lLght beam 47, respectively, form the attack element 12.

9~

In Figure 15, a further embodiment of the present invention is shown in perspective view. This embodiment comprises a beam 25 extending across the web according to Figure 6 and attack elements according to Figure 8. The balls 33 slide on the inclined runoff plate 3 in line with the crosswise motion generated by the motion generator 100 according to the arrow 26 and back and Eorth with the superimposed back and forth rotary motion of the motion generator 200 according to the arrow 27 and are subjected to additional displacements by the piston/cylinder unlts 28. In the case of the substan*ially vertical piston/
cylinder units 28, the balls 33 can be pulled entirely out of the foam layer 6 as is shown in Figures 6 and 8, while the substantially horizontal piston/
cylinder units 28 pull up the balls 33 fastened thereto closer to the beam 25 or continue to keep them away therefrom.
In the embodiment of Figure 15, the foam layer 6 is generated by a wide slit nozzle 50 which extends over the entire width of the web 1 and the area 5. The foam layer 6 generated can be further equalized in its motion in the direction of the arrow 7 over the area 5 by wiper arrangements (not shown) before the attack elements 12 formed by the balls exert their pattern forming effect. The foam layer goes from the lower edge 8 of the plate 3 to the web of material 1 which travels underneath in the direction oE the arrow 2 and is accepted immediately by the latter. This is indicated by the Erequency of the foam bubbles, which decrease towards the right hand edge 1' of the web of material 1. The distance to the complete collapse oE the foam and its complete absorption by the web can be substantially longer than is shown in Figure 15.
~ n Figure 16, a Eurther embodiment of the present invention is shown in perspective view in which the Eoam layer 6 :Ls generated by a wicle slit nozzle 50 on the web 1 and the attack elements act in the foam already present on the web 1.

291~

In Figure 17, a control for an arrangement according to Figures ]5 or 16 which permits producing repetitive patterns is illustrated.
A hydraulic pump 60 supplies, via servo valves 61 and 62 respectively, pressurized ]iquid to the motion generator 100 which is designed as a hydraulic lifting cylinder, or to the motion generator 200 which is designed as a hydraulic rotary motor. The servo valves 61 and 62 are controlled by programs on endless program curves 63, 64 and 65 on endless belts 66, 67 and 68. The endless belts 66, 67 and 68 are driven by motors 69, 70 and 71 at a predetermined speed. The program cur~es 63, 64 and 65 are scanned by reading units 72, 73 and 74 which are shown only schematically and deliver a voltage or current corresponding to the excursion, which appears amplified and as an electric set-value quantity at the output of the desired value transmi~ter 75, 76 and 77. For the motion generator 100, two program curves 63 and 64 are provided in the example, which are superimposed in an adding unit 78 and processed into a resulting desired value. The desired value at the output of the desired value transmitter 75 and the adding unit 78, respectively, is fed to a desired actual value comparator 79, into which an electric signal representing the piston position in the motion generator 100, designed as a piston/cylinder unit. Another signal, which is obtained by transmitting the motion of the piston rod 80 to a linear potentiometer 81 and converting the potentiometer output in an actual value transmitter 82 into a suitable :Lnput variable for the desired actual value comparator 79 is also fed to comparator 79. The servo value 61 is therefore controlled ln accordance with the cllEference between the deslred value corresponcllng to the lnstantaneous excurslon value o the program curve~63 and the actual position.
Correspondingly, the motion generator 200 is connected to a rotary potentiometer 83, the output signal of which is processed in an actual value ;29~

transmitter 84 and is fed, together with the output signal of the desired-value transmitter 77, into a desired actual value comparator 85 which then controls the servo valve 62 which determLnes the rotation of the support 25. It is understood that the rotation also can be modified by superimposing several program curves similar to the program curves 63 and 64.
Ir"portant embod:Lments of :the present invention are shown in Figures 18 and 19. In the embodiment according to Figure 1, the foam layer 6 slides down over the plate 3 under the action of gravity in the direction of the arrow 7, and -then is transferred to the web 1. The velocity oE the sliding foam layer is limited. If the pattern formed on the plate 3 is to be transferred to the web 1 without distortion, its forward velocity must correspond to the velocity of the layer 6 which is sliding down over the plate 3. In such a case, this limits the permissible forward velocity of the web 1 and thereby, the operating speed of the pattern generating apparatus. If forward velocity of the web 1 is increased, the patterns formed on the web 1 are stretched, which is undesir-able particularly because the web 1 thereby is given a pronounced preferred direction.
In the devices according to Figures 2 and 3, the web runs with the same velocity as the belt 14 or the drum 20. Instead, however, an engagement takes place at the foam layer 6, inasmuch as the web 1 runs UpOII the foam layer 6 Erom above and locks up the foam layer 6 between the belt :L4 or the drum 20 and the web 1, and ls urged lnto the web 1. Thereby, the pattern formed ln the Eoam layer 6 is changed ln a.manner which is at t~nes desired but is not desir able ln other cases.
Also lf the web 1 were not restlng agalnst the belt 14 or the drum 20 but were to run along the belt 14 or the drum 20 with very little spacing, the pattern would be influenced when the foam layer 6 îs transferred to the web 1, inasmuch as the foam layer 6 would be partially torn up. The distinctness of the pattern is lost and practice has shown that only very blurred pattern structures can be generated in this manner.
'Ln the embodiments according to Figures 2 and 3, the velocity of the revolving elements :L~ and 20, ls automatically the same as that oE the web 1.
This, too, ls not always desirable'because somet-lmes, deslred interventions into the appearance of the patterns are possible by changing the velocity ratio.
The further problem arises here to transfer a patterned foam layer to a running web while preserying the pattern and without intervention at the foam layer from above, without automatic ties between the velocity of the foam layer and the velocity of the web.
In the embodiment according to Figure 18, the foam layer 6 is generated as in the embodiment according to Figure 3 on a revolving drum 120, but without contact between the web 1 and the drum 120. Rather, the web 1 runs, in the manner seen in Figure 18, underneath the drum 120 with a spacing; the axis of the drum extends transversely to the web of material 1 parallel to and above the web. On the descendlng side, for rotation ln the direction of the arrow, a wiper 101 rests against the drum 120; this wiper has the form of an elongated rectangular slat, the top edge 102 of which touches the drum 120 and strips-off the foam layer formed on the drum 120, which then slides down over the wiper 101 which is inclined downward at an angle with respect to the web 1 and is transferred Erom the lower edge 103 oE the wiper 101, arranged a'bove the web 1,to the web of materlal 1. The foam layer 6 thus gets onto the web 1 wit'hout engagement of the foam layer 6 from above and wlthout tles between the forward velocity of the web 1 and the speed of rotation of the drum 120.

~31296 The drum 120 is driven by the motor 106, while the drive for the web 1 is shown schematically by an arrangement where a support roll 107 which advances the web, i5 driven by the motor 108. The motors 106 and 108 are both controlled by a control device 109 which controls the forward velocity of the web l and the speed of rotation oE drum 120 in a mutual relationship which can be selected at will.
The manner in which the pattern indicated by the lines 105 is generated in the foam layer 6 is immaterial to the principle of operation of the embodiments shown in Figures 18 and 19.
In the embodimert of Figure 18, a slit nozzle 50 is provided, according to Figures 15 and 16, which extends over the width of the web 1 and by means of which a uniform foam layer is generated to which a pattern is then applied at a point following in the direction of rotation of the drum 120, by engagement elements 12 mounted at motion generators 10.
The embodiment of Figure 19 differs from the embodiment ac~ording to Figure 18 in that the revolving element is not a drum but an endless belt 114 which is conducted over two cylinders 115 and 118 which have mutually parallel exes arranged above the web oE material 1 and extending transversely thereto.
The lower section of the belt 114 ls disposed above the web 1 with spacing.
In Figure 19, also, the removal of the faam layer 6 is accomplished by a wiper 101 which rests against the outside oE the belt 14 on the side of the cylinder :l8 descending during revolution. The belt is aclvantageous:ly clesigned AS a steel belt.
The patterned Eoam layer 6 is generated by several foam applicators 110 which may be movable transversely to the web, indepenclently of each other, delivering Eoam to the web. The pattern is obtainecl by causing diEferent foams to come in contact at different places of the web, or while one and the same foam emerges from the foam applicators 110, this foam is present with different heights at different points of the web. The relief of the foam layers 6 generated in this manner manifests itself in a corresponding pattern on the web 1, such as a pattern of different depths of color.
The pattern applicatlon by means of slit nozæles 50 and engaging elements 12 as per Figure 18, can be applied in the embodiment described in Figure 19 and vice versa.
The embodiments accordlng to Flgures 18 and 19 permlt a higher forward velocity o the web 1 than the embodiment according to Figure 1 because the drum 120 or the belt accelerate the foam layer 6 and push lt down via the wlper 101. Although appllcation velocities which are arbitrarily high cannot be obtained because of the very llmited ability of the foam to transmlt pressure, a distlnct improYement of the performance over an embodiment such as that ln Flgure 1 is observed. ~ contribution in this direction is added if the wiper 101 is made rather thin.
By means of the control devices 109 and variation of the relative speed of the web and roller, the pattern generated on the web 1 can be stretched lengthwise in a desired manner or shortened in the longitudinal direction.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A method for applying patterns to a continuously advancing web of material with a treatment medium contained in a foam, in which the foam is present in a layer before or after being transferred to the web, comprising making the foam uneven in the layer in places or traces.

2. The method according to claim 1, comprising displacing the foam in places or traces.

3. The method according to claim 1, comprising removing the foam in places or traces.

4. The method according to claim 1, comprising adding a gaseous, liquid or solid treatment medium for the faom or the web of material to the foam in places or traces.

5. An apparatus for applying patterns to a continuously advancing web of material comprising a foam generating device and a foam applicator, by means of which the foam can be applied to the web of material in layer form over the width of the web of material, and a device for making patterns in the layer, the improvement comprising:
a) at least one motion generator arranged above the web of material;
and b) at attack element connected thereto for making the foam layer uneven in places or traces.

6. The improvement according to claim 5, wherein a plurality of attack elements are provided and wherein said motion generator is common to several attack elements

7. The improvement according to claim 6, wherein said motion generator comprises a beam which is arranged transverse to the web of material above the web, supported for rotation back and forth and movement parallel to itself, and motion generating means connected to said beam.

8. The improvement according to claim 5, wherein a plurality of attack elements are provided and a separate motion generator is associated with each attack element.

9. The improvement according to claim 5 and further comprising a device for switching off or lifting off the attack element from the web of material associated with at least one motion generator.

10. The improvement according to claim 5 wherein said attack element is a rod-like or strip-like member, which protrudes to at least the proximity of the web of material.

11. The improvement according to claim 10, wherein said attack element is substantially rigid.

12. The improvement according to claim 10, wherein said attack element is flexible.

13. The improvement according to claim 5, wherein said attack element is a flexible drag member, optionally with a pendulum body attached to one end.

14. The improvement according to claim 13, wherein said pendulum body rests on the web of material.

15. The improvement according to claim 13, wherein said pendulum body is a sphere.

16. The improvement according to claim 13 wherein said pendulum body is a body bounded by at least one plane surface.

17. The improvement according to claim 5 wherein said attack element is a suction trunk which is in communication with a suction line.

18. The improvement according to claim 5 wherein said attack element is a spraying device by means of which a narrowly defined jet of a treatment medium in gaseous, liquid or powder form can be directed toward the foam layer.

19. The improvement according to claim 5 wherein said attack element is a light source by means of which a narrowly defined light or infrared beam can be directed toward the foam layer.

20. Method for applying a pattern to a continuously advancing web with a treatment medium contained in a foam comprising:
a) applying the foam to an element rotating about an axis extending transversely to the web;
b) generating a patterned foam layer on the element;
c) wiping the foam off from the revolving element with a wiper blade and transferring it by the wiper blade to the web of material which passes underneath without making contact; and d) controlling the forward velocity of the web of material and the speed of rotation of the revolving element to obtain a desired pattern effect on the web.

21. The method according to claim 20, comprising applying a uniform foam layer to the revolving element, and patterning foam layer after application to the revolving element.

22. The method according to claim 20, comprising applying foams to the revolving element from different foam applicators, to form a patterned foam layer on the revolving element.

23. A device for applying patterns to a continuously advancing web with a foam containing treatment medium, comprising:
means revolving about an axis extending transversely to the web;
means arranged above the revolving element for generating a patterned foam layer on the revolving element;
a wiper extending transversely over the web, having an upper edge and a lower edge, said upper edge resting against the side of said revolving means descending during roation for stripping the foam layer from the revolving element, and said lower edge disposed above the web of material and parallel thereto; and means for controlling the forward velocity of the web of material and the speed of rotation of the revolving element in a selectable mutual relationship.

24. A device according to claim 23, comprising a device for applying a foam layer which is coherent over the width of the web, disposed above said means revolving and, at a point following in the direction of rotation, at least one motion generator and an engagement element connected thereto.

25. A device according to claim 23, comprising at least two foam feeding devices arranged to form a patterned foam layer on said means revolving disposed above said means revolving.

26. A device according to claim 23, wherein said means revolving is a drum which extends above the web and rotates about an axis extending trans-versely thereto.

27. A device according to claim 23, wherein said means revolving comprises an endless revolving belt which is conducted over two cylinders revolving above the web about axes extending transversely to the web.