GB2379178A

GB2379178A - Foam masking tapes

Info

Publication number: GB2379178A
Application number: GB0218074A
Authority: GB
Inventors: Oliver Jevons
Original assignee: Jevtec Ltd
Current assignee: Jevtec Ltd
Priority date: 2001-08-31
Filing date: 2002-08-05
Publication date: 2003-03-05
Anticipated expiration: 2022-08-05
Also published as: GB2379178B; AU2002324115A1; WO2003020438A2; GB0218074D0; AU2002324115A8; GB0121080D0; WO2003020438A3

Abstract

There is disclosed a foam masking tape 11 adapted to mask gaps between moving members, such as doors (12 figure 6) and fixed structure (13 figure 6) of automobiles during spraying, comprising a strip of flat foam material 14 having lengthwise extending edges 15, 16 one edge 15 being secured against a face 17 of the foam material so as to create a rounded formation (18, figure 2). The tape having an adhesive strip 19 on its face at or near an edge remote from the rounded formation (18). Also disclosed is a method of manufacturing such a tape, apparatus (figure 7) for manufacturing the tape and a method of using the tape. The apparatus comprises a former (73 figure 7) which folds the tape over on itself prior to adhesive being added.

Description

Foam Masking Tapes This invention relates to foam masking tapes, more particularly to foam masking tapes used to mask the gaps between moving members, such as doors, and fixed structure of automobiles during spraying A masking tape is described in WO 99/12654 (PCT/GB/02706) which has a bullet-like cross-section with a rounded end and an adhesive strip on a face at an edge remote from the rounded end. Such a tape, of dimensions within a certain range, can effectively mask all apertures on a vehicle, including doors, boot (trunk) and bonnet (hood) during spraying, or, more usually, respraying, after bodywork, and has indeed been marketed by 3M (UK) Ltd under the name"Universal", signifying, no doubt, that it covers all apertures for which, previously, a range of tape sizes and formats was required, and then some.

The 3M tape is made by the process of cold welding, as described in EP 0384624, in which foam sheet is divided into strips by rollers which not only cut the foam but also weld it by virtue of fusion due to the heat caused by compression between the rollers. The tape described in WO 99/12654 is made by a different operation, which does not involve cold welding, so that it can be made without infringing 3M's EP 0384626.

Both tapes are used in the manner prescribed in WO 99/12654, namely by attaching the adhesive strip to the moving member, e. g. the door, and closing the moving member on to the fixed structure, e. g. the door post, so that it protrudes slightly, then adjusting it with regard to the gap by running a finger around the gap.

The tape as described in WO 99/12654 is somewhat more expensive to manufacture than the 3M version, although it has the advantage that it can accommodate a lengthwise

recess which hold the adhesive, or which, on rolling the tape up for packing, lies opposite the adhesive strip, so that the adhesive is held free of the next layer of tape and the tape unrolls more easily. Both tapes are, however, more expensive, because they contain more foam, than the 3M tapes they were meant to replace, many bodyshops prefer to use the old product, despite the numerous advantages of the new tapes in regard to ease of use, simplification of inventory, and masking gaps for which the old tapes are totally unsuitable.

The present invention provides a novel foam masking tape which has all the advantages of the earlier'bullet section'tapes, but is easier to manufacture, it can be less expensive even than the old style tapes of 3M, because it need not contain so much foam, and can be capable of being packed, length for length, in a smaller box, reducing storage space and transportation costs.

The invention comprises a foam masking tape adapted to mask gaps between moving members, such as doors, and fixed structure of automobiles during spraying, comprising a strip of flat foam material having lengthwise-extending edges, one edge being secured against a surface of the foam material so as to create a rounded formation, the tape having an adhesive strip on its face at or near an edge remote from the rounded formation..

The strip may be folded edge-to-edge, and the facing regions may then be adhesively secured together. At least one of said facing edge regions may be secured with adhesive to adhere to the other of said facing edge regions, Edge regions may, however, be secured together by a strip of adhesive tape, which may be single or double sided adhesive tape, and which may be an adhesive paper masking tape.

The said one edge may be secured against a face of the foam material by a cold weld seam.

The strip may be adhesively secured face-to-face between at least one edge and the rounded formation.

The strip may have the adhesive strip on its face in or opposite a facial recess whereby when the tape is wound on a spool the adhesive strip is out of contact with an adjacent turn of tape on the spool.

The invention also comprises a method for manufacturing a foam masking tape adapted to mask gaps between moving members, such as doors, and fixed structure of automobiles, comprising folding a strip of flat foam material having lengthwiseextending edges so that one edge is against a face of the foam material and there securing it so as to create a rounded formation, and applying an adhesive stripe to a face of the material at or near an edge remote from the rounded formation.

The strip may be folded edge-to-edge, and facing edge regions may be adhesively secured together. At least one of said facing edge regions may be coated with adhesive and the edge regions pressed together. However, a strip of adhesive tape may be attached along one edge region and pressed against the other. The tape may be double sided adhesive, and may be adhesive paper masking tape.

Said one edge may be secured against a face of the foam material by a cold weld seam.

The tape may be adhesively secured face-to-face between at least one edge and the rounded formation.

The strip may be locally melted to provide the adhesive. Hot air may be blown on to the tape to melt it, and the strip may be folded to place one or both edges along the melt line or lines, and the folded strip pressed to form a bond. The folded strip may be pressed between nip rollers to form the bond.

The adhesive stripe may be applied by a holt melt applicator. The tape may be cooled after application of the adhesive stripe and before winding up the tape. The tape may pass through a cooling zone at room temperature to cool it. Cold air may be blown on to the tape.

The adhesive stripe may be placed on or opposite a facial recess and the tape wound on a spool with the adhesive stripe thereby out of contact with an adjacent turn of tape on the spool.

The tape may be wound on to a spool which is wider than the tape and traversed across the spool as it is being wound.

The invention also comprises a foam masking tape for masking the interior of a vehicle during spraying and comprising a foam strip with an adhesive stripe that can be attached to the moving member (such as the door) or the fixed structure surrounding the moving member of a vehicle opening so that when the moving member is closed on the fixed structure the foam strip bridges the gap therebetween, the masking tape having an elongated profile with the adhesive stripe at one edge of a wide face thereof and, on the opposite face, a stress-relieving slot.

The slot may be midway along said opposite face.

The slot may extend into the tape by about half the thickness of the tape.

The tape may comprise a strip of flat foam material having lengthwise-extending edges, one edge being secured against a face of the foam material so as to create a rounded formation, the other edge also being secured against said face of the strip so as to butt against said one edge, whereby to form said slot.

The said other edge need not, however, butt against the said one edge, but can be spaced therefrom.

The slot may comprise a slit part way through a monolithic foam structure.

The invention also comprises apparatus for making a foam masking tape comprising a support for a supply of flat foam strip, a former through which the strip passes to have at least one edge folded back on to the face of the strip, applicator means applying an adhesive to said folded back edge or edges, press means to press the folded strip to secure adhesive attachment, and wind-up means to wind up the thus produced tape.

The said adhesive applicator means may comprise hot air nozzle means playing hot air on to the face of the strip to produce local melting for adhesion.

The said adhesive applicator means may, however, comprise a support and delivery means for delivering an adhesive tape to said folder means to contact said folded back edge or at least one of said folded back edges. Such an apparatus can be used to make a masking tape from a strip of flat foam and a strip of adhesive tape (such as adhesive paper masking tape) in which the adhesive tape not only affords the adhesive for attachment to the foam strip to form a tubular structure but also affords the adhesive for the adhesive foam masking tape per se, if the edges of the foam strip do not meet on the adhesive tape thereby leaving a section of it exposed for adhesion to a surface for masking purposes.

The apparatus may also comprise a hot melt applicator (obviously redundant, so far as concerns the last-mentioned tape in which adhesive for surface attachment is afforded by the adhesive tape) for applying an adhesive stripe to the folded tape.

The apparatus also comprises a tape wind-up arrangement comprising a driven spool, wider than the tape, and a tape traversing arrangement spreading said tape over the spool as it is being wound.

The apparatus may also comprise an adjustment arrangement for centering or offsetting the foam strip with respect to the folder to produce different tape configurations.

The invention also comprises a method for masking gaps between moving members, such as doors, and fixed structure of automobiles, comprising attaching a foam masking tape according to the invention or made by a method according to the invention, by its adhesive stripe, to the inside edge of the moving member whilst such is open, and closing the moving member, all so as to then trap the tape between the closed moving member and the fixed structure with the rounded formation level with or protruding from the gap, and adjusting the position of the rounded formation by finger or like pressure run around the gap so that it is level.

A first coat may be applied by spraying, then the tape may be adjusted, again by finger or like pressure run around the gap, to lie a little deeper in the gap, then a second coat may be applied by spraying.

Embodiments of foam masking tapes according to the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a first embodiment of tape; Figure 2 is a cross-section of a second embodiment of tape; Figure 3 is a cross-section showing a stage in the manufacture of the tape of Figure 1;

Figure 4 is a cross-section of a third embodiment of tape; Figure 5 is a cross-section of a fourth embodiment of tape; Figure 6 shows the tape of Figure 2 in position masking a gap between an automobile door and fixed structure of the automobile; Figure 7 is a diagrammatic illustration of one embodiment of apparatus for making masking tape according to the invention; Figure 8 is a diagrammatic illustration of a second embodiment of apparatus for making masking tape according to the invention; and Figure 9 is a cross-section through a monolithic tape according to one aspect of the invention.

The drawings illustrate foam masking tapes 11 adapted to mask gaps between moving members, such as doors 12, and fixed structure 13 (Figure 6) of automobiles during spraying. The tapes 11 each comprise a strip of flat foam material 14 having lengthwiseextending edges 15,16, one edge, 15, being secured against a face 17 of the foam material 14 so as to create a rounded formation 18, the tape having an adhesive stripe 19 on its face at or near an edge 15,16, remote from the rounded formation 18.

Figures 1 to 3 illustrate tapes 11 in which the strip 14 is folded edge-to edge, the edge 15 being against the edge 16, whether as a butt joint Figures 2 and 3, or face-to-face as in Figure 1. In the drawings, the facing edge regions are shown adhesively secured together. At least one of the facing edge regions 15,16 is coated with adhesive to adhere to the other of the facing edge regions. However, instead of adhesive, which usually, in this context, means melt adhesive, the edge regions may be secured together by a strip

of adhesive tape, which may be double-sided adhesive, and which may be adhesive paper masking tape.

The tape illustrated in Figure 1 could be made using the cold welding process referred to above, in which the edges 15,16 are cold welded by roller pressure on arrows A, B, Figure 3. Whether cold welding or adhesive (liquid adhesive or paper tape) is used to secure the edges 15.16 together against the face 14a of the strip, as shown in Figure 3, the strip of Figure 1 is made simply by cutting the double strip of Figure 4 along arrow C.

The adhesive stripe 19 is applied as melt adhesive or as double sided adhesive tape.

Figures 4 and 5 illustrate foam masking tapes 11 in which the strips are adhesively secured face-to-face between one edge, 15 and the rounded formation 18. The tape illustrated in Figure 5 has its edge 15 secured against face 14a of the strip 14 by a strip of single sided adhesive tape 21, while the tape illustrated in Figure 6 has its edge 15 secured against the face 14a of the strip by melt adhesive or by double sided adhesive tape. The adhesive stripe 19, for attachment to the vehicle, is applied either as melt adhesive or as double sided adhesive masking tape.

In the embodiments of Figures 4 and 5, the adhesive stripe 19 (which could in either case be on the opposite face as shown at 19a) is in or, respectively, opposite a facial recess 22 whereby when the tape is wound on a spool the adhesive strip is out of contact with an adjacent turn of tape on the spool.

Figure 1 simply shows how the new tape, in this case the embodiment of Figure 2, is used. The adhesive stripe 19 is attached around the inside outer edge of an open door 12 of an automobile so that the tape projects beyond the edge of the door 12-solid lines. The door 12 is then closed against the fixed structure 13 of the automobile, and the tape is trapped between door and fixed structure-broken line. The tape can be adjusted as

necessary by light finger pressure in the direction of arrow D to be left projecting slightly from the gap, or to lie flush, or to be slightly recessed in the gap.

Figure 7 illustrates one embodiment of apparatus for making masking tapes according to the invention.

The apparatus comprises a support 71 for a jumbo roll of flat foam strip 72. A former 73, like a scroll of a sewing machine for turning a hem, but double sided, so that it can turn in both edges of the tape 72, is arranged to be fed with strip 72 from the roll, which is pulled through the former 73 by the action of a pair of nip rolls 74.

Nozzles 75 supply hot air (at, typically, 420 C) along two lines each just off-centre on either side of the upper face 72a of the strip 72 while the strip is in the former 73, but before the edges are rolled. The edges of the strip are rolled over the heated lines, which have melted so as to be adhesive, and the nip rolls 74 press the rolled edges down on to the now adhesive lines.

An adhesive stripe is applied just inboard of one edge of the now folded and pressed tape by a hot melt adhesive applicator 76 and the tape is led through an air space 77 in which the adhesive cools and dries to a wind-up arrangement 78 with a tape traverse mechanism 81 spreading the tape across a spool 79 wider than the tape.

To make the embodiment of tape illustrated in Figure 3, the edges of the strip 72 are butted together. By laterally adjusting the strip 72 with respect to the former 73, a tape as illustrated in Figure 2 can be made. By folding only one edge, a tape like that shown in Figure 4, or like the one shown in Figure 5 can be made.

Yet different ways of folding, which may require different configurations of the former 73 can be made such as that shown in Figure 1. With tapes like those illustrated in

Figures 2 and 3, instead of abutting the edges of the strip, they can be left separated by a space.

Figure 8 shows another embodiment of apparatus for making tape according to the invention, which is basically the same as that shown in Figure 7 except that, instead of the nozzles 75, an adhesive masking tape 82 based on paper of the kind commonly sold, eg. for masking windows when painting the frames, is fed into the former.

The tape 82 can be double sided, in which case it will produce a tape as illustrated in Figure 3, except that the paper tape will be between the two layers of strip 72. By using a single sided paper tape, which attaches to the edges only, not the face of the tape over which the edges are folded, a different kind of foam masking tape will be produced, such as is illustrated in International Patent Application WO 99/12654.

Depending on whether the adhesive tape is exposed through a gap between the folded over edges or not, the hot melt applicator 76 may not be needed to operate.

Some of the tapes made according to the invention, namely those illustrated in Figures 2 and 3 (and shown in use in Figure 6) have a slot on the broad face of the tape opposite the face carrying the adhesive stripe. This is found to relieve stress in the tape when it is bent by the action of closing the moving member. It has been found with monolithic tapes of the kind illustrated in Figure 9 that the action of closing the moving member can so stress the tape as to pull the adhesive stripe away from its anchorage on the moving member or surround, but that this does not happen with the slotted tapes. The invention also comprises therefore a monolithic tape 91 with a slit 92 cut midway between its edges to about half depth.

By contrast to the 3M Universal product, the tape according to the present invention has a better and more uniform rounded edge 17 because it is formed by folding a flat tape

rather than by the cold welding process. The folding operation can be effected readily through a simple folding device such as is used for folding seams on a sewing machine and the application of adhesive whether as melt adhesive or adhesive masking tape is a straightforward operation requiring no very expensive machinery and which can be performed at high speed.

Because the tapes, particularly such as those illustrated in Figures 4 and 5 are'hollow', there is less foam material in them than in the solid 3M Universal tapes and they can be made with as little material, or even less material, than the earlier 3M Soft Edge tapes.

Because of the reduction in the amount of raw material used, and because of the simplification of the manufacturing process, the cost of the tapes can be reduced, as can the cost of the packaging, as less material in the tape means less material in the box for a given length of tape.

Claims

CLAIMS 1. A foam masking tape adapted to mask gaps between moving members, such as doors, and fixed structure of automobiles during spraying, comprising a strip of flat foam material having lengthwise extending edges one edge being secured against a face of the foam material so as to create a rounded formation, the tape having an adhesive strip on its face at or near an edge remote from the rounded formation.
2. A tape according to claim 1, in which the strip is folded edge-to-edge.
3. A tape according to claim 2, in which the facing edge regions are adhesively secured together.
4. A tape according to claim 3, in which at least one of said facing edge regions is coated with adhesive to adhere to the other of said facing edge regions.
5. A tape according to claim 3 or claim 4, in which the edge regions are secured together by a strip of adhesive tape.
6. A tape according to claim 5, in which said adhesive tape is double-sided adhesive.
7. A tape according to claim 5 or claim 6, in which said adhesive tape is adhesive paper masking tape.
8. A tape according to claim 1 or claim 2, in which the said one edge is secured against a face of the foam material by a cold weld seam.

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9. A tape according to any one of claims 1 to 8, in which the strip is adhesively secured face-to-face between at least one edge and the rounded formation.
10. A tape according to any one of claims 1 to 9, having the adhesive strip on its face in or opposite a facial recess whereby when the tape is wound on a spool the adhesive stripe is out of contact with an adjacent turn of tape on the spool.
11. A method of manufacturing a foam masking tape adapted to mask gaps between moving members, such as doors, and fixed structure of automobiles, comprising folding a strip of flat foam material having lengthwise extending edges so that one edge is against a face of the foam material and there securing it so as to create a rounded formation, and applying an adhesive stripe to a face of the material at or near an edge remote from the rounded formation.
12. A method according to claim 11, in which the strip is folded edge-to-edge.
13. A method according to claim 12, in which facing edge regions are adhesively secured together.
14. A method according to claim 13, in which at least one of said facing edge regions is coated with adhesive and the edge regions pressed together.
15. A method according to claim 13 or claim 13, in which a strip of adhesive tape is attached along one edge region and pressed against the other.
16. A method according to claim 15, in which the tape is double-sided adhesive.
17. A method according to claim 15 or claim 16, in which the said adhesive tape is adhesive paper masking tape.

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18. A method according to claim 11 or claim 12, in which the said one edge is secured against a face of the foam material by a cold weld seam.
19. A method according to any one of claims 11 to 18, in which the tape is adhesively secured face-to-face between at least one edge and the rounded formation.
20. A method according to claim 19, in which the strip is locally melted to provide the adhesive.
21. A method according to claim 20, in which hot air is blown on to the tape to melt it, and the strip is folded to pace one or both edges along the melt line or lines, and the folded strip pressed to form a bond.
22. A method according to claim 21, in which the folded tape is pressed between nip rollers to form the bond.
23. A method according to any one of claims 11 to 22, in which the adhesive stripe is applied by a hot melt applicator.
24. A method according to claim 23, in which the tape is cooled after application of the adhesive stripe and before winding up the tape.
25. A method according to claim 24, in which the tape passes through a cooling zone at room temperature to cool it.
26. A method according to claim 25, in which cold air is blown onto the tape.

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27. A method according to any one of claims 11 to 20, in which the adhesive stripe is placed in or opposite a facial recess and the tape wound on a spool with the adhesive stripe thereby out of contact with an adjacent turn of tape in the spool.
28. A method according to any one of claims 11 to 26, in which the tape is wound on to a spool which is wider than the tape and traversed across the spool as it is being wound.
29. A foam masking tape for masking the interior of a vehicle during spraying and comprising a foam strip with an adhesive stripe that can be attached to the moving member (such as the door) or the fixed structure surrounding the moving member of a vehicle opening so that when the moving member is closed on to the fixed structure the foam strip bridges the gap therebetween, the masking tape having an elongated profile with the adhesive stripe at one edge of a wide face thereof and, on the opposite face, a stress-relieving slot.
30. A tape according to claim 29, in which the slot is midway along said opposite face.
31. A tape according to claim 29 or claim 30, in which the slot extends into the tape by about half the thickness of the tape.
32. A tape according to any one of claims 29 to 31, which comprises a strip of flat foam material having lengthwise-extending edges one edge being secured against a face of the foam material so as to create a rounded formation the other edge also being secured against said face of the strip so as to butt against said one edge, whereby to form said slot.

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33. A tape according to any one of claims 29 to 32, in which the slot comprises a slit part way through a monolithic foam structure.
34. Apparatus for making a foam masking tape comprising a support for a supply of flat foam strip, a former through which the strip passes to have at least one edge folded back on to the face of the strip, applicator means applying an adhesive to said folded back edge or edges, press means to press the folded strip to secure adhesive attachment, and wind-up means to wind up the thus produced tape.
35. Apparatus according to claim 34, in which the adhesive applicator means comprise hot air nozzle means playing hot air on to the face of the strip to produce local melting to adhesion.
36. Apparatus according to claim 34, in which the adhesive applicator means comprise a support and delivery means for delivering an adhesive tape to said folder means to contact said folded back edge or at least one of said folded back edges.
37. Apparatus according to any one of claims 34 to 36, comprising a hot melt applicator for applying an adhesive stripe to the folded tape.
38. Apparatus according to any one of claims 34 to 37, comprising a tape windup arrangement comprising a driven spool, wider than the tape, and a tape traversing arrangement spreading said tape over the spool as it is being wound.
39. Apparatus according to any one of claims 34 to 38, comprising an adjustment arrangement for centering or offsetting the foam strip with respect to the folder to produce different tape configurations.

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40. A method for masking gaps between moving members, such as doors, and fixed structure of automobiles, comprising attaching a foam masking tape according to any one of claims 1 to 10 or made by a method according to any one of claims 11 to 28, by its adhesive stripe, to the inside edge of the moving member whilst such is open, and closing the moving member all so as to then trap the tape between the closed moving member and the fixed structure with the rounded formation level with or protruding slightly from the tape, and adjusting the position of the rounded formation by finger or like pressure run around the tape so that it is level.
41. A method according to claim 40, in which a first coat is applied by spraying, then the tape is adjusted, again by finger or like pressure run around the tape, to lie a little deeper in the tap, then a second coat is applied by spraying.