AU651752B2 - Stencilled paving - Google Patents

Description

1 Al IPrm F AUSTRALIA 0 1 PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor: BARRIE DAVID COOPER Barrie David Cooper Address for Service: SHELSTON WATERS 55 Clarence Street SYDNEY NSW 2000 Inn Invention Title: "STENCILLED PAVING" Details of Associated Provisional Application No: PL0598 dated 28th January 1992 The following statement is a full description of this invention, including the best method of performing it known to me:- 2 This invention relates to a method for providing a pavement and to an article for use in the method.

Traditional methods of paving involve laying cobbles, bricks, paving stones, or other pavers in pattern "herring bone", "basket weave", "running bond") on a suitable flat foundation. The joints between adjacent pavers may be filled with a cementious material or with sand or soil.

Pavements which simulate the appearance of hand \oo 10 laid paving have been formed by incising grooves in a wet cement surface by means of a trowel, the cement being 2coloured by oxides or the like to simulate bricks or other pavers, and the grooves being differently coloured to resemble joints.

.e 15 It has also been practiced to form grooves in a wet cement surface using a suitably shaped rigid grid form work. More recently a technique has been developed in which a stencil is placed onto an existing, old or new, fully cured concrete slab, the stencil being then oversprayed with a coating material which dries or cures to resemble a paving material. The stencil protects the slab from build up of the coating along lines which resemble the pattern of joints between pavers. The depressions remaining on removal of the stencil may, if desired, be precoloured to resemble a coloured mortar or may be left the colour of the underlying concrete.

The stencils used to produce simulated paving have hitherto been made from plastic sheets, each several 3 metres square, which are diecut to provide the "paving joint" shapes required. The stencil sheets are placed on the concrete base in contiguous alignment and fixed in position prior to application of the coating material.

When the coating material is sufficiently hardened, the stencil sheets are removed leaving a grooved pattern resembling paving joints.

The stencil sheets must meet stringent performance requirements and in particular must have sufficient dry and wet strength to withstand rough handling during laying and alignment as well as during spraying and subsequent removal. Stencils hitherto available have been costly to manufacture and labour intensive to set out in arrays. It is an object of the present invention to provide a less labour intensive method of pavement stencilling and to provide improved stencils for use in the method.

According to one ,.spect the invention consists in a method of forming a simulated paver comprising the 20 steps of: o. unwinding a continuous length of stencil from a roll, the stencil being comprised predominantly of a paper, or a reinforced paper, which has been cut to define apertures; i 25 adhering the stencil to a substrate, and applying a composition to the substrate through apertures of the stencil.

According to a second aspect the invention consists *s C 4 in a stencil comprising paper or reinforced paper from which apertures have been cut, the total area of the cut apertures being greater in comparison with the area of the remainder, the stencil having a pressure sensitive adhesive on one surface and being wound onto a roll.

In preferred embodiments of the invention the stencil is composed of a fibreglass fibre reinforced paper. Desirably the paper is waterproofed by being plastic coated, preferably with polyethylene. In a highly preferred embodiment the stencil is provided with islands of pressure sensitive adhesive on one side and a release agent on the other.

The invention will now be more particularly described by way of example only with reference to the accompanying drawings wherein: Figure 1 shows a portion of a stencil according to the invention in plan view, Figure 2 shows schematically an enlarged cross section through the stencil, and 20 Figure 3 shows schematically apparatus for manufacture of stencils according to the invention.

With reference to figures 1 and 2 there is shown a stencil according to the invention. The stencil is made ifrom high wet strength kraft paper 1 having a fibreglass 25 reinforcing 2 and a thickness of from 220 to 230 micrometres. Paper I is coated on one side with a layer 3 of polyethylene and has a silicone release coating 4 on the polyethylene. The opposite side of paper 1 is

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/j 9 z\ r 5 printed with pressure sensitive adhesive dots 5. In the present example the pressure sensitive adhesive is applied from a water emulsion for example Revacril A258.

With reference to Fic- e 3 the polyethylene coated fibreglass reinforced kraft sheet 21 is fed from a feed spool 22 via a tension controlling roller 23 to pass between a die-roller 24 and anvil-roller 25 whereby the sheet is cut into a stencilled pattern. The diecut stencil 26 which defines apertures 32 between strip 10 members 33 then passes through a glue station 27 wherein glue is picked up from a tray 28 via a pick up roller 29 and applied via a roller 30 to a rotogravure roller 31.

Rotogravure roller 31 prints dots or islands of pressure sensitive adhesive on one side of the stencil. The 15 stencil then passes through a hot air dryer 34 to dry the adhesive and is rolled up on a take up spool 35 with the adhesive printed side in contact with the release coating of an underlying layer. Importantly the stencil is made :in long continuous lengths which are wound onto a take up roll. It will be understood that the off cuts (and hence apertures 32) are of large area in comparison with the remaining strips 33. For example the apertures may be cm by 9.5 cm and the strips 1.5 cm wide.

In use a roll of stencil is placed on the surface or on a trolley cradle and one end of the stencil is laid on a cementious base with the adhesive side down so that the stencil end is adhered to the surface. The stencil may then be unrolled from the stencil roll. As the 6 stencil roll is rolled along the surface, stencil is unwonmd onto the surface in long straight runs and adhered to the surface by means of the pressure sensitive adhesive. If necessary the process can be repeated in adjacent strips to cover a wide area. In comparison with the labour required to lay out and align adjacent sheets in a 3-dimensional array the process of laying out a stencil according to the invention from a continuous roll can be accomplished in much less time and at much lower *o*o 10 cost. Furthermore the stencil itself is of substantially 9*99 o* lower cost than the prior art, while having an excellent e wet and dry strength and resisting delamination.

The pavement may be formed by applying a composition to substrate through apertures of the stencil *5*9 15 of the invention for example by overspraying a grit and aggregate filled thermoplastic coating composition, a chlorinated rubber based composition, or more preferably a cement based paint composition such as that marketed under the WESTOX trade mark in a variety of colours.

Although the stencil has been described as of paper which is reinforced with glass fibres it will be appreciated that the paper may be reinforced by use of fibres other than glass fibres, for example by nylon, kevlar or carbon fibres.

The paper may also or instead be reinforced without use of fibres for example by impregnation with plastics or by lamination. Likewise in other embodiments the paper of the stencil may be rendered waterproof by 7 impregnation, lamination or surface coating and waterproofing agents and resins other than polyethylene may be employed. Recycled paper fibres may be used and, to an extent which will be apparent to those skilled in the art, other papers may be substituted for kraft papers.

As will be apparent to those skilled in the art from the description herein contained, the stencil may be provided in a variety of forms suitable for provision of various paving patents such as basket weave, herring 10 bone, stretchabond and the like.

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Claims (23)

1. A method of forming a simulated paver comprising the steps of: unwinding a continuous length of stencil from a roll, the stencil being comprised predominantly of a paper, or a reinforced paper, which has been cut to define apertures; adhering the stencil to a substrate; and applying a composition to the substrate through apertures of the stencil.

2. The method according to claim 1, wherein the stencil is composed of fibreglass fibre reinforced paper.

3. The method a according to claim 1, wherein the stencil is composed of a nylon fibre reinforced paper, a kevlar fibre reinforced paper, or a carbon fibre reinforced paper.

4. The method according to claim 1 wherein the paper is reinforced by impregnation with plastics or by lamination.

5. The method according to any preceding claim, 20 wherein the paper is waterproofed by impregnation, lamination, or surface coating.

6. The method according to claim 5, wherein the paper is waterproofed by a plastic coating.

7. The method according to claim 6, wherein the plastic coating is polyethelyene.

8. The method according to any one of the preceding claims, wherein the stencil is provided with islands of *e 4 9 pressure sensitive adhesive on one side and a release agent on the other.

9. The method according to claim 8, wherein the release agent is a silicone release coating.

10. The method according to any one of the preceding claims, wherein the paper is a high wet strength kraft paper.

11. The method according to any of the preceding claims, wherein the composition is a grit and aggregate filled thermoplastic coating composition, a chlorinated rubber base composition, or a cement based paint composition.

12. A stencil comprising paper or reinforced paper from which apertures have been cut, the total area of the cut apertures being greater in comparison with the area of the remainder, the stencil having a pressure sensitive adhesive on one surface and being wound onto a roll.

13. The stencil according to claim 12, wherein the stencil is composed of fibreglass fibre reinforced paper. 20

14. The stencil according to claim 12, wherein the stencil is composed of a nylon fibre reinforced paper, a kevlar fibre reinforced paper, or a carbon fiLre reinforced paper.

The stencil according to cj.aim 12, wherein the 25 paper is reinforced by impregnation with plastics or by lamination.

16. The stencil according to any one of claims 12 to 15, wherein the paper is waterproofed by impregnation, lamination, or surface coating. JS 10

17. The stencil according to claim 16, wherein the paper is waterproofed by a plastic coating.

18. The stencil according to claim 17, wherein the plastic coating is polyethelyene.

19. The stencil according to any one of claims 12 to 18, wherein the stencil is provided with islands of pressure sensitive adhesive on one side and a release agent on the other.

The stencil according to claim 19, wherein the release agent is a silicone release coating.

21. The stencil according to any one of claims 12 to wherein the paper is a high wet strength kraft paper.

22. The stencil according to any one of claims 12 to 21, wherein a composition comprising a grit and aggregate filled thermoplastic coating, a composition comprising chlorinated rubber base, or a composition comprising cement based paint is applied through the cut apertures to a substrate.

23. A method substantially as hereinbefore described 20 with reference to the accompanying drawings. S24. A stencil substantially as hereinbefore described with reference to the accompanying drawings. S. DATED this 23rd day of MAY, 1994. BARRIE DAVID COOPER Attorney: PETER HEATHCOTE Fellow Institute of Patent Attorneys of Australia S*.of SHELSTON WATERS *4 5 go ":oo I .1 11 ABSTRACT The invention relates to a method of forming a simulated pavement comprising the steps of unwinding a continuous length of stencil from a roll, the stencil being comprised predominantly of paper or a reinforced paper, which has been cut to define apertures adhering the stencil to a substrate, and applying a composition to the substrate through apertures of the stencil. 0 o