GB2175852A

GB2175852A - Decorating vinyl curtain sides for vehicles

Info

Publication number: GB2175852A
Application number: GB08612946A
Authority: GB
Inventors: Philip Eric Boyle; Clifford John Allen
Original assignee: Johnson Matthey PLC
Current assignee: Johnson Matthey PLC
Priority date: 1985-05-30
Filing date: 1986-05-28
Publication date: 1986-12-10
Also published as: GB8612946D0; GB2175852B; GB8513679D0

Abstract

A method for decorating a vinyl curtain side 6 (e.g. for a lorry) in which the curtain side 6 and a transfer 7 (consisting of a design backed with heat activateable adhesive and a support sheet) are laid on a perforated support 1, then a vacuum is applied beneath the support 1 and the transfer 7 is heated to cause the design 7b to become bonded to the curtain side 6. As shown in Fig. 2, the flexible sheet 8 enables a pressure differential between the cover 9 and the peripheral evacuated space bordering the substrate to urge the transfer onto the substrate. <IMAGE>

Description

SPECIFICATION Decorating vinyl curtain sides for vehicles This invention relates to a method for decorating vinyl curtain sides for vehicles, especially lorries. "Curtain side" is the name given to the vinyl (usually plasticised polyvinyl chloride) sheeting used to close open sides in the large box-like structures often provided on vehicles for the purpose of housing goods being transported.

It is commercially desirable to decorate curtain sides using transfers. One method for doing this comprises first softening the vinyl sheeting with a solvent, then depositing the transfer design onto the softened sheeting and finally painting over the design with a lacquer containing more solvent which softens the sheeting.

The problem with transfer-decorated curtain sides is that when the vehicle is travelling at high speed, the curtain side flaps vigorously with a high frequency which loosens the transferred design causing the design to flake off the vinyl sheeting. An object of this invention is to provide a method for decorating vinyl curtain sides using transfers which method results in the transferred design having improved resistance to flaking.

Accordingly this invention provides a method for decorating a vinyl curtain side in which a) the vinyl curtain side is laid on a perforated support then b) a transfer comprising a design sandwiched between a release support and a layer of heat-activateable adhesive is laid adhesiveside down onto the curtain side then c) the curtain side and transfer are subjected to a pressure gradient by reducing pressure beneath the perforated support then d) whilst maintaining the pressure gradient the adhesive is heated to a temperature sufficient to activate the adhesive then e) the adhesive is cooled or allowed to cool and then f) the release support is removed from the design.

Preferably the adhesive is heated by radiant heat directed (usually vertically) downwards.

The preferred source of heat is a bank of infra-red lamps. Preferably the curtain side and the transfer are subjected to a pressure gradient of from 700 to 1000 mbar to achieve optimum resistance to flaking. Preferably the design is made up from elastomeric ink.

The heat activateable adhesive may be any substance which after it has been heated sufficiently causes the design to adhere to the curtain side. The preferred adhesives are heat fusible substances especially thermoplastic organic polymers which melt on heating and then re-solidify on cooling causing the design to become bonded to the curtain side. Useful adhesives include polyethylene, ethylene/propylene copolymers, ethylene vinylacetate copolymer, polyvinyl chloride, cellulose acetobutyrate or cellulose acetopropionate, polyacrylics or acrylic/butadiene copolymers, (optionally plasticised) polyamides and thermoplastic (preferably aliphatic) polyurethanes. Elastomeric adhesives are especially preferred because they are better able to withstand high frequency flapping.

The release support serves to carry the design and the heat-activateable prior to their application to the curtain side. The release support should therefore be easily removeable from the design and also resistant to the heat used to activate the adhesive. A wide variety of release papers are available for use as the release support and preferred papers include papers coated with a chrome/fatty acid complex or with polypropylene.

The exposed surface of the design bonded to the curtain side may be protected by painting it with a lacquer comprising organic material such as polyurethane or polyacrylic dispersed in a liquid (for example water) which does not soften the vinyl sheeting so that when the lacquer dries, the design is covered with a layer of the organic polymeric material.

Painting may be performed for example by brush coating or by spraying.

The invention is further illqstrated by the following description which refers to the drawings in which Figure 1 is an exploded perspective view part in section showing the arrangement of a curtain side and a transfer above a perforated support, Figure 2 shows in section the arrangement shown in Fig. 1 just prior to heating and Figure 3 shows in section a decorated curtain side after removal of the release support.

Fig. 1 shows a perforated support 1 having perforations 2 (only a few of which are shown for simplicity). Perforated support 1 forms part of a hollow box 3 containing a chamber 4 in which the pressure can be reduced by means of evacuating line 5. Positioned above perforated support 1 are a vinyl curtain side 6, a transfer 7, a scrim 12 having an open weave, a flexible rubber sealing membrane 8 and a frame 9 having dependent sealing flanges 10 and carrying banks of infra-red heating lamps 11 (only five of which are shown).Curtain side 6, transfer 7, scrim 12, membrane 8 and frame 9 are placed one on top of another on perforated support 1 as shown in Fig. 2 from which it will be seen that flanges 10 press membrane 8 into sealing contact with perforated support 1 so ensuring that a pressure gradient is established across transfer 7 and curtain side 6 when the pressure below perforated support 1 is reduced by means of line 5. Scrim 12 serves to promote an even pressure gradient and in particular minimises the risk of blisters forming.

Figs. 1 and 2 each show that transfer 7 consists of a release paper 7a, a design layer 7b and a layer of heat-activateable adhesive 7c.

Fig. 3 shows transfer-decorated curtain side 6 after release paper 7a has been removed following the application of heat from lamps 11 to bond design layer 7b to curtain side 1 by adhesive 7c.

The invention is also illustrated by the following Example.

EXAMPLE A curtain side consisting of plasticised polyvinyl chloride sheeting was decorated by applying a transfer using the arrangement illustrated by the drawings. The transfer comprised a release paper coated on its under side with a complex of chrome and fatty acid and a layer of heat-activateable adhesive consisting of a crystallising thermoplastic elastomeric polyurethane. The pressure below the perforated surface was reduced to about 980 mbar and the transfer was heated for 3 minutes using 385 watt 115 volt infra-red lamps.

After heating, the transfer was allowed to cool for 1 minute and then the release paper was peeled from the design layer. A transferdecorated curtain side was obtained which had good resistance to flaking.

Claims

1. A method for decorating a vinyl curtain side in which a) the vinyl curtain side is laid on a perforated support then b) a transfer comprising a design sandwiched between a release support and a layer of heat-activateable adhesive is laid adhesiveside down onto the curtain side then c) the curtain side and transfer are subjected to a pressure gradient by reducing pressure beneath the perforated support then d) whilst maintaining the pressure gradient the adhesive is heated to a temperature sufficient to activate the adhesive then e) the adhesive is cooled or allowed to cool and then f) the release support is removed from the design.

2. A method according to Claim 1 wherein the pressure gradient is from 700 to 1000 mbar.

3. A method according to Claim 1 or 2 wherein the adhesive is heated by downwardly directed radiant heat.

4. A method according to any one of the preceding claims wherein the adhesive is a elastomeric thermoplastic organic polymer.

5. A method according to Claim 4 wherein the adhesive comprises polyurethane.

6. A method according to Claim 4 wherein the adhesive comprises polyamide.

7. A method according to any one of the preceding claims wherein after the release support has been removed, the exposed surface of the design is painted with a lacquer comprising organic polymeric material dispersed in a liquid which does not soften the vinyl sheeting.

8. A method according to Claim 7 wherein the lacquer comprises an organic polymeric material which is a polyurethane.

9. A method according to Claim 7 wherein the lacquer comprises an organic polymeric material which is a polyacrylic.

10. A method according to any one of the preceding claims wherein a flexible sealing membrane is placed over the transfer on the curtain side and the membrane is spaced from the transfer by a scrim.