GB2143175A - Clear plastics sheet having opaque protective layer - Google Patents

Clear plastics sheet having opaque protective layer Download PDF

Info

Publication number
GB2143175A
GB2143175A GB08415786A GB8415786A GB2143175A GB 2143175 A GB2143175 A GB 2143175A GB 08415786 A GB08415786 A GB 08415786A GB 8415786 A GB8415786 A GB 8415786A GB 2143175 A GB2143175 A GB 2143175A
Authority
GB
United Kingdom
Prior art keywords
sheet
transparent
rigid plastics
plastics sheet
adhered
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08415786A
Other versions
GB8415786D0 (en
GB2143175B (en
Inventor
Michael Cass
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Imperial Chemical Industries Ltd
Original Assignee
Imperial Chemical Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB838318938A external-priority patent/GB8318938D0/en
Application filed by Imperial Chemical Industries Ltd filed Critical Imperial Chemical Industries Ltd
Priority to GB08415786A priority Critical patent/GB2143175B/en
Publication of GB8415786D0 publication Critical patent/GB8415786D0/en
Publication of GB2143175A publication Critical patent/GB2143175A/en
Application granted granted Critical
Publication of GB2143175B publication Critical patent/GB2143175B/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B32B38/0036—Heat treatment
    • B32B38/004—Heat treatment by physically contacting the layers, e.g. by the use of heated platens or rollers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/023—Optical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/40—Properties of the layers or laminate having particular optical properties
    • B32B2307/402—Coloured
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/40—Properties of the layers or laminate having particular optical properties
    • B32B2307/41—Opaque
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/40—Properties of the layers or laminate having particular optical properties
    • B32B2307/412—Transparent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/40—Properties of the layers or laminate having particular optical properties
    • B32B2307/416—Reflective
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/04—Polyethylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2605/00—Vehicles

Abstract

A transparent, rigid plastics sheet carrying an adhered, protective layer of a coloured, opaque film of an ethylene polymer on at least one of the surfaces of the sheet. At least part of the protective layer is subsequently left adhered to the sheet to form part of an article fabricated from the sheet. Useful for providing vehicle number plates or signs wherein the legend cut from the opaque film is provided with a suitable backing. In the case of the vehicle number plate this backing would be a layer of retro reflective material to provide visibility of the legend under conditions of poor visibility. <IMAGE>

Description

SPECIFICATION Clear plastics sheet having opaque protective layer This invention relates to a transparent plastics sheet carrying a protective surface of a coloured, opaque film on at least one surface of the sheet and to articles formed from the sheet.
Clear plastics sheet, such as acrylic sheet, is normally supplied carrying a removeable, protective layer to protect the surface of the sheet from scratching during handling. This protective layer may be of paper but more usually is of transparent polyethylene film. This is normally removed from sheet when the sheet is in use, but if the sheet is to be thermoformed it may be left in place for the thermoforming operation. For example, bath shells can be thermoformed from acrylic sheet with a polyethylene film left in contact with the sheet during the thermoforming operation. The protective film can be left in place until the bath has been installed and connected to the services.The present invention provides a plastics sheet which is used in applications in which at least part of the protective layer is left in place and forms part of the article which has been fabricated from the sheet and its adherent protective layer.
According to the invention there is provided a transparent, rigid plastics sheet carrying an adhered, protective layer of a coloured, opaque film of polyethylene on at least one of the surfaces of the sheet.
By an opaque film is meant a film having a luminous transmittance of zero measured according to ASTMD 1003-59T.
The provision of the coloured, opaque polyethylene film adhered to the clear sheet enables a variety of useful end products to be made from the laminate.
For example, the laminate of sheet and polyethylene film provides an ideal starting point for the provision of vehicle number plates. In the United Kingdom vehicle number plates have black lettering on a white background for number plates on the front of the vehicle and black lettering on a yellow background for the rear of the vehicle. These plates are currently produced from clear extruded acrylic sheet by removing the protective, transparent polyethylene film normally present on the sheet and either printing the required lettering through a stencil or by first applying a self adhesive film of black polyvinyl chloride (PVC) to the clear sheet and subsequently cutting through the PVC using clicking dies and presses to provide the required lettering. The surplus part of the PVC film surrounding the lettering is then peeled off.The lettering is then provided with a protective cover in the form of a retro reflective layer to provide the necessary visibility of the number plate in poorly lit conditions. In assembly the clear sheet provides the visible surface of the number plate so that the printing or stamping out of the lettering is done as the mirror image of that required to be visible.
The present invention provides a useful raw material as the starting point for a number of products in which part of the protective layer is incorporated in articles fabricated from the protected sheet. Thus there is provided a transparent, rigid plastics sheet carrying an adhered legend which has been cut from a coloured, opaque film of polyethylene adhered to the rigid plastics sheet. Thus in order to provide a vehicle number plate the fabricator can be provided with a protected sheet or number plate blank carrying an adhered film of black polyethylene which is immediately ready for stamping to provide the required black lettering without the need to remove the existing transparent polyethylene and apply a separate layer of PVC. The lettering is subsequently provided with a retroreflective layer as described above.The opaque, coloured polyethylene layer may be varied in colour to meet the legal traffic requirements of an individual country.
The protected sheet of the invention may be used in any other application in which use can be made of the coloured, opaque polyethylene film for decorative or other useful purpose.
For example, the protected sheet can be used in the construction of signs from clear sheet.
Thus the legend of the sign can be cut from the opaque, coloured film and the decorated sheet can be assembled as a flat sheet with an appropriate backing. Alternatively, the appropriately decorated sheet can be thermoformed into a shaping suitable for sign work. In this method it is preferable that the polyethylene film is on the surface of the sheet opposite to the surface of the sheet which is urged against the mould surface to define the shape.
In any event the sign should be assembled so that the plastics sheet provides the outermost surface of the sign and provides weather protection for the adhered polyethylene legend. The polyethylene film may be additionally protected by the application of a lacquer.
The polyethylene film may be adhered to the sheet of the invention by means of a suitable adhesive, such as a pressure sensitive adhesive. Although this is the preferred form of adhesion it is possible to provide a securely adhered film to the plastics sheet by the application of heat and pressure to an assembly of polyethylene film and plastics sheet, particularly an acrylic sheet. When no adhesive is present on the polyethylene film it is preferred that it is pretreated by corona discharge.
The polyethylene film should preferably have a thickness of at least 40 microns, preferably at least 50 microns in order to perform the function of protection during handling. Thicker films may be used, for example 1 30 micron film, but above 150 microns in thickness there is no additional benefit for the additional cost incurred. The polyethylene film should preferably have a melt flow index as determined using the ASTM Method 1238-70 of between 1 and 4, preferably 2 and 3.
It is to be understood that the term polyethylene includes copolymers of ethylene with minor amounts of copolymerisable monomers.
Where the adhesion between the film and the sheet is obtained through the use of heat and pressure, it is useful to use a copolymer which will give rise to good adhesion. For example, copolymers with vinyl acetate or the esters of acrylic and methacrylic acids will give increased adhesion compared to the homopolymer of polyethylene.

Claims (10)

1. A transparent, rigid plastics sheet carrying an adhered protective layer of a coloured, opaque film of polyethylene on at least one of the surfaces of the sheet.
2. A transparent, rigid plastics sheet according to claim 1 in which the opaque film is adhered to the sheet by means of heat and pressure.
3. A transparent, rigid plastics sheet carrying an adhered legend which has been cut from a coloured, opaque film of polyethylene adhered to the rigid plastics sheet.
4. An article which has been thermoformed from a sheet according to claim 3 against a mould surface to define a shape.
5. . A transparent, rigid plastics sheet according to claim 3 wherein the side of the sheet carrying the legend is provided with a backing.
6. An article according to claim 4 wherein the side of the sheet carrying the legend is provided with. a backing.
7. A transparent rigid plastics sheet according to claim 5 wherein the backing is a retro-reflective layer.
8. A transparent rigid plastics sheet according to claim 7 in the form of a vehicle number plate.
9. A transparent rigid plastics sheet according to any one of claims 1, 2, 3, 5, 7 and 8 wherein the opaque polyethylene film is black.
10. A transparent, rigid plastics sheet according to any one of claims 1, 2, 3, 5, 7, 8 and 9 in which the plastic sheet is of an acrylic polymer.
GB08415786A 1983-07-13 1984-06-20 Clear plastics sheet having opaque protective layer Expired GB2143175B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB08415786A GB2143175B (en) 1983-07-13 1984-06-20 Clear plastics sheet having opaque protective layer

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB838318938A GB8318938D0 (en) 1983-07-13 1983-07-13 Protected clear plastics sheet
GB08415786A GB2143175B (en) 1983-07-13 1984-06-20 Clear plastics sheet having opaque protective layer

Publications (3)

Publication Number Publication Date
GB8415786D0 GB8415786D0 (en) 1984-07-25
GB2143175A true GB2143175A (en) 1985-02-06
GB2143175B GB2143175B (en) 1987-05-07

Family

ID=26286594

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08415786A Expired GB2143175B (en) 1983-07-13 1984-06-20 Clear plastics sheet having opaque protective layer

Country Status (1)

Country Link
GB (1) GB2143175B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2849414A1 (en) * 2002-12-30 2004-07-02 Ind Samar T PROTECTOR FOR REGISTRATION PLATES

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB954103A (en) * 1961-12-11 1964-04-02 Ici Ltd Display panels
EP0071160B1 (en) * 1981-07-21 1985-06-12 Dai Nippon Insatsu Kabushiki Kaisha Plastic card having metallic luster

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB954103A (en) * 1961-12-11 1964-04-02 Ici Ltd Display panels
EP0071160B1 (en) * 1981-07-21 1985-06-12 Dai Nippon Insatsu Kabushiki Kaisha Plastic card having metallic luster

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2849414A1 (en) * 2002-12-30 2004-07-02 Ind Samar T PROTECTOR FOR REGISTRATION PLATES

Also Published As

Publication number Publication date
GB8415786D0 (en) 1984-07-25
GB2143175B (en) 1987-05-07

Similar Documents

Publication Publication Date Title
EP0291178B1 (en) Retroreflective sheeting with backing film
EP0223564B1 (en) Transparent multi-layer cover film for retroreflective sheeting
EP0223565B1 (en) Enclosed-lens retroreflective sheeting having tough weather-resistant, transparent cover film
EP0997750B1 (en) Retroreflective sheeting containing a validation image and methods of making the same
EP0578750B1 (en) Stable pressure sensitive shrink label technique
US6155689A (en) Perforated retroreflective film
EP1145050B1 (en) Cube corner cavity based retroreflectors with transparent fill material
KR101721515B1 (en) Retroreflective article comprising retroreflective prism elements and an etched reflective metal coating
EP1512583B1 (en) License plate for back illumination and method for making same
JP2000502815A (en) Labor saving method and article for producing three-dimensional sign board graphics
JP2960478B2 (en) Retroreflective sheeting
JP3594969B2 (en) Retroreflective license plate and method of manufacturing the same
EP1627246B1 (en) Retroreflective article comprising microstructured adhesive layer
KR20020053873A (en) Method of making signs having metalized cube corner sheeting
GB2143175A (en) Clear plastics sheet having opaque protective layer
EP0870978A1 (en) A light conducting plate, method for making the same and using thereof
EP0326186B1 (en) High-angularity retroreflective sheeting and method for manufacture
EP1489439B1 (en) Method of making a retroreflective sheeting containing a validation image
JP2939497B2 (en) Thermocompression laminated film

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19930620