Preformed fully adhesive cone sleeve

Abstract

 A method for securing a close fitting preformed sleeve 12 onto a support surface 10. The sleeve 12 is coated internally with adhesive and the adhesive is covered by a liquid layer, such as isopropanol to prevent the adhesive contacting the body 10 while the sleeve is being fitted thereon. The sleeve dimensions are no larger than the body and preferably smaller so as to provide the close fit.

Description

[0001] This invention relates to the method of application of sleeves to traffic guidance devices and in particular, road cones, cylinders and the like.

[0002] Road cones (and other devices) have, for many years, been equipped with sleeves or bands of material which are often retro-reflective and/or contrast with the body colour of the cone so that the visual image presented, meets the prescribed requirements of the authorities controlling such items in the country of use. Generally, the method of achieving the application of the bands was by one of two methods.

[0003] Method A - Pre-manufacture of a "sleeve" or "collar" such that it duplicated the tapered angles of the cone. Such a sleeve is first cut to shape as a flat projection of the desired band and the two ends of the flat shape are joined together for example by welding to form a three dimensional shape that can be slipped over the cone. Sometimes, such sleeves or collars are used only at night and thus are not permanently fixed to the cone by adhesive. Where such sleeves or collars are fixed to a cone by adhesive, a convenient method is to apply a small blob or area of adhesive to the cone body at an appropriate height within the area to be covered by the sleeve. The area coated by adhesive is normally substantially less than the whole area to be covered by the sleeve. Normally, the adhesive chosen is of a syrupy consistency and solvent based such that it allows some final adjustment of position of the sleeve relative to the cone. It will be understood by those who have practised this art that the greater the area of the cone covered by the sleeve, the greater is the requirement for the adhesive to cover a proportionally smaller area of the surface of the cone which is likely to contact the sleeve (or vice-versa) or, the more syrupy the adhesive must be at the time when the sleeve is fitted on to the cone. These provisions either permit the application of a large area sleeve by allowing the last area of the sleeve reaching the surface of the cone to be in that area where adhesive is present or because the adhesive properties allow the sleeve to be moved to its final position prior to final adhesion. In other words, the thicker, tackier or more aggressive the glue used, combined with the proportions of the area of the surface covered by the glue, the greater is the difficulty in fixing the sleeve in its correct position before the glue overcomes the efforts of the person attempting to fit it. The greater the area of the sleeve, the greater the problem faced using a preformed sleeve. It is for these reasons that until now, preformed sleeves have been either small, or fixed by adhesive over only a small part of their surface.

[0004] Method B - This method employs a band made from a flat pre-cut shape of self adhesive material, wherein substantially the whole of the surface that will eventually contact the cone body is covered with a contact or pressure sensitive adhesive. It has proven almost impossible to apply such a band as a preformed sleeve or collar. This is because even the most skilled person has very great difficulty in introducing the preformed collar over the cone such that it reaches the desired position before one or more points of adhesive contact are made in the wrong position.

[0005] It is equally difficult for the unmade up flat shape described to be positioned accurately by hand so that it may be wrapped around the cone body. Unless this is done extremely carefully, the result is unsightly. This problem has been the subject of other solution attempts, examples of which are disclosed in UK Patent Application No.2096214A and European Patent EP 0405880 B1. Both of these put forward the need for complex machine solutions to overcome the difficulties.

[0006] The inventors know of no instance where a preformed three dimensional sleeve has been commercially offered which is made from a substantially fully pressure sensitive backed material. Even the use of double sided adhesive tape did not involve more than 15% of the total contact area.

[0007] The major difference between the finally resulting products achieved by methods A and B is that the bands produced by method A are not fully adhered over the whole supporting surface whereas the bands produced by method B are fully adhered. Thus, if products made by method A become damaged at a point remote from the adhesive, the edges of the damage are loose and can flap, thereby propagating a tear line in the material or even resulting in the eventual loss of the sleeve or band.

[0008] Method A has many advantages over method B however, in that it is easier to carry out by manual means, and thus is less costly in time, with less waste through spoilage. Method A also provides an easy means of improving the appearance of an old or scuffed or blemished cone, whereas method B does not.

[0009] The disadvantages in the performance of products made by method A have recently resulted in demands by controlling authorities in at least one country that bands applied to cones shall be totally or substantially totally adhered to the cone over the whole under surface of the band. Additionally, controlling authorities in at least one country have required that instead of one or more retro-reflective bands being applied discreetly, they now require the whole cone to be retro-reflective. In at least one country, the authorities will, in future, require the whole cone to be fully retro-reflective, and that the retro-reflective material applied to the cone will be adhered to the cone over the whole surface area of substantially the whole surface area. Products made by method A cannot meet these requirements.

[0010] Attempts to improve method A methods have been made to extend the area of coverage of a syrupy adhesive so that substantially the whole area of the sleeve is covered, and the cone sleeve is then introduced to the cone. It was found that the preformed sleeve could be positioned correctly in the desired location only with difficulty due to the relatively large surface areas involved. Also, it was found that much thicker coatings of adhesive than is desirable were needed to allow the slippage required to move the sleeve into the required position. In most of the adhesives tried, the presence of significantly greater total volume of the solvents providing the slip characteristics (than were present in a small area blob as previous art) were detrimental to the materials used in the manufacture of the sleeve and in some instances to the cone. Also, where previously only small areas of adhesive were present, surrounded by larger areas without adhesive, the surrounding air evaporated these small quantities of solvents relatively quickly. Conversely, whole surface coatings of adhesive provided no means by which the solvents could evaporate from any area other than those in close proximity to the edges or periphery of the sleeve.

[0011] Where reduced thicknesses of adhesive were used, it was found almost impossible to move the sleeve into its final desired position on all but small surface area sleeves, due to the resistance to movement created by the adhesive.

[0012] The use of water based adhesive to overcome solvent attack, did allow correct positioning, but wherever the cone body and the preformed sleeve were manufactured from substantially impervious to water materials as is usually the case, there was no route by which the water contained in the adhesive could evaporate to allow the adhesive to develop its final characteristics, the result being at best, a band or sleeve adhered only at the periphery of the bands where some evaporation could occur.

[0013] The present invention has been made in order to deal with these problems.

[0014] According to one aspect of the invention there is provided a method for securing a preformed sleeve closely fitted onto a complementary support body wherein said sleeve and/or said body is coated at least in part with pressure sensitive adhesive, said method comprising the provision of a liquid layer between the adhesive on the sleeve and the surface of the body and/or sleeve so as to permit the sleeve to be moved relative to the support body and thereafter securing said sleeve to the body with the adhesive.

[0015] In order to obtain a really good close fit between the preformed sleeve and the support body, the preformed sleeve should be no larger than the body on which it is to be fitted and preferably somewhat smaller than the body, for example by as much as 10%, but typically such that the internal dimension of the sleeve is from 1/16 to ⅛ inch smaller than the corresponding dimension of the support body. The preformed sleeve may need to be stretched in order to get it into position on the body. The preformed sleeve may also be warmed to assist fitting onto the support body. Generally a temperature above ambient, but not exceeding 40°C is suitable.

[0016] The liquid layer primarily has only a temporary role that is to permit the movement of the sleeve relative to the body. The liquid can be water or any other liquid which does not react with the adhesive, but acts mechanically to provide a physical barrier between the adhesive and the surface of the sleeve and/or cone to which the adhesive is to adhere. When the sleeve is in its desired position the barrier is broken down, for example by the application of pressure to the sleeve so that the adhesive secures the sleeve to the body.

[0017] The liquid may have a further role in that it can have an effect in the adhesion process, for example by triggering a cross-linking reaction.

[0018] In another embodiment of the invention the liquid may be one which, while permitting movement of the sleeve relative to the body, also has a, possibly time dependent, action on the adhesive. For example the liquid may be a solvent for the adhesive, the solvent characteristics of which are only manifest for a limited period of time, or the liquid may be one which, after a limited period of time, acts directly on the adhesive to promote curing thereof.

[0019] In another aspect of the invention there is provided a preformed sleeve, receivable on a body, a plurality of apertures in the sleeve and or the body, an excess of adhesive or adhesive solvent being applied to the sleeve and/or to the body whereby said excess adhesive or adhesive solvent permits the sleeve to be moved relative to the body into a predetermined position whereupon excess adhesive or adhesive solvent escapes or can be extruded through the said apertures in the film.

[0020] In a preferred embodiment of the invention a preformed sleeve is coated on its inner surface, i.e. the one that will come into eventual contact with the supporting body with a pressure sensitive adhesive. It is unimportant whether such adhesive is of the water based, solvent based or hot melt, reactive hot melt or other type, for example double sided adhesive tape. After allowing the pressure sensitive adhesive characteristics of the adhesive to be developed, the sleeve is immersed in a container of, or is sprayed with, a suitable liquid such as water or a solution of water containing a wetting agent so that when the preformed sleeve is introduced over the top of the body and moved into its desired final position, the liquid film present at the surface interface between the body and the sleeve prevents the adhesive from "grabbing" until the desired positioning is achieved.

[0021] It was found that whilst the liquid film is present, sleeve positioning could be easily and quickly achieved and that by "smoothing" out any excess liquid from the centre of the sleeve to the edges, the aggressive nature of the pressure sensitive adhesive progressively overcame the interference by the liquid, encouraging remaining liquid to migrate to the edges until a bond was achieved over substantial areas of the available interface between the body and the preformed sleeve. Any remaining liquid evaporates or migrates over a period of time. If some coalesced areas of liquid remain it does not significantly reduce the overall effect or practical result. The inclusion of small holes in the preformed sleeve material can help this process.

[0022] As already mentioned the liquid may be water or any other liquid which will permit movement of the sleeve relative to the body.

[0023] Using the invention it has been found that it is possible also to introduce close fitting pressure sensitive adhesive coated preformed sleeves on to complementary shaped bodies including cones and cylinders. Indeed, if the material which the sleeve is made from is elastic to some degree, the sleeve may even be introduced over a body of larger dimension than the unstretched sleeve dimension without damage. This enables the sleeve to be moved to a final position where there is an undercut or smaller dimension section designed to receive the sleeve.

[0024] In the same way a sleeve can be fitted to a cone where the sleeve which has a diameter at its top opening which is smaller than the diameter of a cross section made through the cone profile immediately above the upper portion where the said band will finally remain. This technique is not limited to cones and can be used with bodies of other shape such as oval or ovoid shaped body or a cylinder or even a large drum or barrel.

[0025] It is not necessary for the adhesive to be present on only one surface of either cone or the sleeve, it may be on either or both.

[0026] This invention is particularly beneficial where a body such as an old cone needs to have a "new" surface applied to it at a site remote from the point of cone or sleeve manufacture. To facilitate this, the adhesive surface of the inside of the preformed sleeve is protected in storage or transit by a release paper such as those well known treated with silicone or wax or a surface to which the adhesive will not normally adhere well to. This protective release film is removed by the purchaser prior to wetting and application of the sleeve to the cone or other device.

[0027] It is not necessary for the whole surface area of the sleeve or body or cone to which the sleeve is to be fitted to be covered with adhesive. The invention is useful wherever there is a portion of the area covered with adhesive which without the use of liquid would make it very difficult to achieve correct positioning of the sleeve on the body.

[0028] Specific embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:-

Figs.1, 2 and 3 illustrates a prior art method (method A) of fixing a sleeve to a body;

Figs.4, 5 and 6 illustrate another prior art method (method B) of fixing a band or strip to a body;

Figs.7 to 11 illustrate the method of the invention.

[0029] Referring to Fig.1 a road cone 10 is to be fitted with a sleeve 12 which extends over only a part of the cone body. Conventionally the sleeve has been held in place with a small "blob" 14 of adhesive. The same technique is used to fit a plurality of small sleeves 12, 12' as shown in Fig.2 or a single sleeve 16 that covers the whole cone surface as shown in Fig.3. These are examples of method A which has been discussed hereinbefore.

[0030] Method B is illustrated by way of example in Fig.4 in which an appropriately shaped strip of material 18 coated with adhesive is wound onto a cone 10. A plurality of such strips 18, 18' can be wound onto the cone as shown in Fig.5 or the cone can be substantially covered by a single piece of material 20 as shown in Fig.6.

[0031] Referring now to Fig.7, in the method of the invention a preformed sleeve 12 coated over the whole of its interior with pressure sensitive adhesive is dipped in a liquid preferably isopropanol or water preferably containing a wetting agent. The sleeve is then placed on the cone and moved into its desired position. Application of pressure to the sleeve causes the adhesive to bond to the cone surface substantially over the whole area covered by the sleeve.

[0032] The preformed sleeve may be made of stretchable material for example of pliable polyvinyl chloride so that it can be moved over body parts of larger dimensions than the sleeve in its unstretched condition. Examples of this are shown in Figs.8 to 11. The provision of a liquid film enables the sleeve 12 to be moved relative to the body 10 notwithstanding the coating of pressure sensitive adhesive on the sleeve and/or the body.

[0033] The close fit of the sleeve on the body ensures the correct reflective or retroreflective performance of the sleeve. If the sleeve is oversize it may develop creases or wrinkles which impair the reflective or retroreflective performance. In addition the close fit prevents rain water penetrating between the sleeve and the body and thus precludes the harmful effect that such penetration would have on the adhesive.

[0034] A further benefit may be derived from this invention through the choice and selection of characteristics in the material used to make up the sleeve together with the degree of adhesion developed by the adhesive. A person knowledgeable in the field of cone sleeve manufacture will know that it is desirable to allow the sleeve to be removable at the end of the life of the cone to enable the cone body material to be recycled in accordance with good environmental practice. The traditional method A employing small adhesive areas sufficient just to retain the sleeve or band in place caters for this need very well, in that the sleeve can easily be cut down its vertical length and rapidly peeled off. Generally, this is because the materials used to construct a preformed method A type sleeve are required to be physically stronger than method B bands, because unlike method B band materials, method A sleeves are not closely physically joined to the cone over their entire area. Thus, because the method A sleeves have to be strong enough to be serviceable in use, they are usually of a strong enough material to enable them to be torn away from the limited area of adhesive used to fix them to a body.

[0035] Conversely, it has been usual for the method B material employed for cone bands to be physically very weak since in use, they enjoy the close physical support of the body to which they adhered. Thus it is exceptionally difficult for the material to be removed from the body at the end of its service life. Since many such method B materials contain glass microspheres and polymeric materials which do not process compatibly with the body material, or are damaging to plastics processing machinery, this difficulty in removing the reflective material is a considerable hindrance to recyclability of the body and re-use of the body material polymer.

[0036] It was initially believed that by making a preformed sleeve fully adhesive over its entire inner surface in accordance with the invention, that similar problems to those presented by method B materials would be encountered when recycling was required at the end of service life. However, it is found that by carefully ensuring that the physical strength of the sleeve material is greater than the bond between it and the adhesive, or preferably greater than the bond between the cone body and adhesive, then it is still possible to remove the sleeve by cutting it vertically and peeling the material back from the exposed edges. By careful selection of adhesive properties, the sleeve may be removed in quite large pieces and in some instances, even in one entire piece. The ability to achieve this is a particular advantage of this invention.

[0037] The sleeve used in the invention can be marked in any way desired, for example to comply with prescribed marking requirements for guidance of traffic on a road, airport, railway or other site.

[0038] If desired the adhesive coating on the sleeve can be protected prior to use by means of release paper. Preferably the release paper is provided with an extension which can be manually grasped so that the release paper can be pulled from the interior of the sleeve through one or other end of the sleeve. Adhesively coated sleeves protected by release paper can be supplied for fitting to bodies, for example on site rather than in the factory.

Claims

1. A method for securing a preformed sleeve closely fitted onto a complementary support body wherein said sleeve and/or said body is coated at least in part with pressure sensitive adhesive, said method comprising the provision of a liquid layer between the adhesive on the sleeve and the surface of the body and/or sleeve so as to permit the sleeve to be moved relative to the support body and thereafter securing said sleeve to the body with the adhesive.

2. A method as claimed in Claim 1 wherein said preformed sleeve is comprised, at least in part, of a retro-reflective material.

3. A method as claimed in Claim 1 or Claim 2 wherein the preformed sleeve is formed by welding the ends of a flat strip together.

4. A method as claimed in Claim 1 or Claim 2 wherein the preformed sleeve is formed by gluing or mechanically fastening the ends of a flat strip together.

5. A method as claimed in any preceding claim wherein the area of the sleeve or body coated with pressure sensitive adhesive is greater than 10% of the available area.

6. A method as claimed in any preceding claim, wherein the area of the sleeve or cone coated with pressure sensitive adhesive is greater than 90% of the available area.

7. A method as claimed in any preceding claim, wherein the sleeve is flexible and/or elastic.

8. A method as claimed in any preceding claim, wherein the sleeve is rigid at least in part.

9. A method as claimed in any preceding claim, wherein more than one colour is present in the sleeve.

10. A method as claimed in any preceding claim, wherein small holes are provided at intervals either in the body and/or in the sleeve whereby liquid and/or adhesive can escape from between the sleeve and the body.

11. A method as claimed in any preceding claim wherein the assembly of the sleeve on the body is effected manually.

12. A method as claimed in any preceding claim wherein the sleeve and/or body coated with pressure sensitive adhesive is provided with a protective release film.

13. A method as claimed in any preceding claim wherein the adhesive is substantially unaffected by water/rain once it has been allowed to develop its pressure sensitive or other adhesive characteristics.

14. A method as claimed in any preceding claim, wherein the strength of the sleeve material is greater than the bond formed between the adhesive and the sleeve and/or the bond formed between the adhesive and the body.

15. A method as claimed in Claim 14, wherein the strength of the sleeve material permits removal of said sleeve from the body by cutting said sleeve and peeling it from the body

16. A method as claimed in Claim 15 wherein the strength of the sleeve is such that pieces of at least 15% of the total sleeve area can be peeled from the body.

17. A method as claimed in any preceding claim wherein the sleeve is marked to provide a visual effect preferably as prescribed .

18. A method as claimed in any preceding claim, wherein the preformed sleeve is not larger than the support body.

19. A method as claimed in Claim 18, wherein the preferred sleeve is up to 10% smaller than the support body.

20. A body such as a cone or other traffic guidance device which has applied to it a preformed sleeve attached by means of pressure sensitive adhesive said sleeve having been positioned in the desired place on the body by the use of a liquid forming a film between the adhesive and the surface of the sleeve or body.

21. A preformed sleeve, receivable on a body, a plurality of apertures in the sleeve and/or the body, an excess of adhesive or adhesive solvent being applied to the sleeve and/or to the body whereby said excess adhesive or adhesive solvent permits the sleeve to be moved relative to the body into a predetermined position whereupon excess adhesive or adhesive solvent escapes or can be extruded through the said apertures in the film.

22. A body such as a cone, bollard, cylinder or the like fitted with a sleeve in accordance with the method as claimed in any of Claims 1 to 17.

Drawing