PANELANDMETHOD OFCREATION
FIELD OF THE INVENTION The present invention relates to the filed of display panels or sheets and, in particular, discloses a method of creating panels suitable for impregnating images into.
BACKGROUND OF THE INVENTION
Illuminated display panels find many uses in society especially where traders wish to advertise or market their products. For example, in fast food outlets, it is common to have a display panel advertising the types of food available. This can be in the form of a back illuminated panel which is partially transparent. The back illumination provides for an attractive end product. Further, colourful panels often provide for atheistically pleasing products. The potential market for display panels is quite large especially where the panels can be made to provide an attractive display. Unfortunately, standard panels such as those formed of Perspex, PNC or polycarbonate have been unsuitable for impregnating images into. Recent products, such as DuPont's SentryGlas (Trade Mark) Expressions (Trade
Mark) allow for attractive glass display panels to be formed having images formed therein. Unfortunately, the quality of images formed within such interlayer material is often poor and these materials can be often difficult to work with for producing improved images.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide for improved forms of forming images on substrates.
In accordance with a first aspect of the present invention, there is provided a method of forming a substrate so that it is suitable for use for impregnating an image, the
method comprising the steps of: (a) providing an initial substrate; (b) heating the initial substrate for an extended period of time so as to substantially remove excess moisture in the substrate.
Preferably, the method also includes the step of slowly cooling the substrate under compression so as to reduce any warping of the substrate due to thermal expansion. The substrate can be formed substantially from acrylic, PNC or polycarbonate. The substrate can be heated for at least 12 hours. The substrate can be heated above substantially 180 Degrees Celsius.
In accordance with a further aspect of the present invention, there is provided a substrate suitable for use for impregnating an image into, the substrate comprising a acrylic, polycarbonate or PNC sheet that has been heated so as to substantially remove excess moisture in the substrate.
Preferably, the substrate is cooled under compression so as to reduce any warping of the substrate due to thermal expansion. Preferably, the substrate is heated for at least 12 hours. The substrate can be heated above substantially 180 Degrees Celsius. In accordance with a further aspect of the present invention, there is provided a method of impregnating an image into a sheet, the method comprising the steps of: (a) forming an image using ink on a first substrate; (b) heating the first substrate so as to reduce the water content of the ink on the first substrate; (c) heating the sheet; (d) pressing the first substrate against the sheet at an elevated temperature;
The method also preferably includes the step of cooling the substrate and sheet whilst they are preferably compressed together. Ideally, this includes maintaining a pressure on the surface of the sheet whilst cooling so as to reduce buckling of the sheet. The step (a) further can comprise altering the gamut curves of the image to account for final variations in the expected gamut curve of the impregnated image.
The impregnated image can be a full colour image and the sheet can be at least partially transparent. In the preferred embodiment, the sheet can be formed from one of acrylic, polyvinylchloride or polycarbonate.
BRIEF DESCRIPTION OF THE DRAWINGS Preferred and other embodiments of the present invention will now be described with reference to the accompanying drawings in which:
FIG. 1. illustrates a flow chart of the steps of the preferred embodiment; FIG 2. illustrates schematically a plan view of an acrylic sheet with the letter A; FIG 3. illustrates sectional view of the cooling process of the preferred embodiment; and
FIG. 4. illustrates a flow chart of the steps of an alternative embodiments.
DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS. In the preferred embodiment, there is provided a method of forming an extremely attractive backlit display. The display can be created fairly simply and has long lasting attractive attributes.
Turning to Fig. 1, there is illustrated a flow chart diagram of the steps involved in the creation of the preferred embodiment. The process starts with the creation of a full colour input image 10 for which it is desired to impregnate in a acrylic, PNC or Polycarbonate sheet. For example, there is illustrated schematically in Fig. 2, a letter A 20 which is desired to be impregnated into a Perspex sheet 21. The first step 10 of Fig. 1 is to input or create the image. The input image is then manipulated so as to improve its gamut curve 11. The manipulation of the gamut curve can be a trial and error process with the output image of a previous iteration being examined so as to determine gamut changes required so as to provide for a more linear gamut in the output display panel.
The manipulation of gamut curves will be readily understood by those skilled in the art of image creation and manipulation and the utilisation of image manipulation programs such as Adobe Photoshop ™.
Next, the image is plotted 12 on a high resolution type ink jet printing device on normal printers paper such as blotting paper. For example, in one experiment, plots were made utilising a Mutoh full colour ink jet printer model RJ8000 series. Although other ink jet printer devices could be utilised.
In the fourth step 13, the image which has been printed on a normal paper substrate is dried so as to remove excess water from the ink. In the drying process 13, the image was dried for 1 hour at 180 Degrees Celsius when utilising standard plotting paper.
Next, the substrate or panel in which it is desired to form the image is heated. For example, where acrylic is utilised, it is ideally heated for 12 hours at 180 Degrees Celsius. The time can be varied depending on equipment and materials utilised. Ideally, a number of samples should be tested using different drying regimes to determine best results.
In the next step 15, the treated substrate and treated image are placed in contact and pressed together. This results in a fusing of the image into the acrylic substrate, hi one embodiment, an acrylic sheet and plotted image were pressed together in a Transmatic heat press at 200 - 225 Degrees Celsius for approximately 300 seconds at 3 bar or 40 PSI pressure.
Next, in the step 16, the substrate and image are left to slowly cool in a compressed state. This can be undertaken as illustrated in Fig. 3, wherein the substrate 30 is compressed between two layers of felt 31, 32 and further two layers of Malanite or
other wood 34, 35. Weights can be placed on top of the Malanite sheet 34 so as to compress the overall arrangement 36.
The arrangement 36 is allowed to cool. Subsequently, the sheet 30 is extracted and the paper 37 is removed. Next, in step 8, the surface can be cleaned and polished.
It was found that the image had been transferred from the plotting paper to the acrylic sheet in a highly stable and attractive manner.
It has also been found that the preferred embodiment works with many different types of transparent and semi-transparent sheets including acrylic, PNC and polycarbonate with the image impregnated into the sheet in a stable and non-destructive manner. This provides for a highly effective form of imaging and allows for the creation of attractive signs and other products such as shower screens, windows etc that can be attractively illuminated.
In the alternative embodiment, there is provided a method of forming an attractive laminated glass structure.
Turning to Fig. 4, there is illustrated a flow chart diagram 40 of the steps involved in the creation of the alternative embodiment. The process starts with the creation of a full colour input image 10 for which it is desired to apply to an EN A, PNB or other form of Cyclone or laminated glass interlayer material. The first step 41 of Fig. 4 is to input or create the image 41. The input image is then manipulated so as to improve its gamut curve 42. The manipulation of the gamut curve can be a trial and error process with the output image of a previous iteration being examined so as to determine gamut changes required so as to provide for a more linear gamut in the output result. The manipulation of gamut curves will be readily understood
by those skilled in the art of image creation and manipulation and the utilisation of image manipulation programs such as Adobe Photoshop ™.
Next, the image is plotted 43 on a high resolution type ink jet printing device on normal printers paper. For example, in one experiment, plots were made utilising a Mutoh full colour ink j et printer model RJ8000 series using a matt coated paper.
Although other ink jet printer devices and paper types could be utilised.
In the next step, the image which has been printed on a paper substrate is dried so as to remove excess water from the ink. In the drying process 44, the image was dried for 1 hour at 180 Degrees Celsius. Next, the substrate or membrane in which it is desired to form the image is dehumidified 45. For example, where PNB is utilised, it can be placed in a dehumidifier for 6 hours at 20 Degrees Celsius to achieve a membrane moisture content of about 20%.
The dehumidification process can be separately optimised for each type of interlayer membrane. In the next step, the dehumidified substrate and dehumidified image are placed in contact and pressed together 46. Four layers of cotton sheet were placed between the paper and the press, and a layer of coated paper was placed between the underside of the press and the membrane. This results in a fusing of the image into the membrane. In one example, a PNB membrane and plotted image were pressed together in a Transmatic heat press at 155-160 Degrees Celsius for approximately 250-300 seconds at 700 hydraulic PSI.
Next, the membrane which has bonded to the paper is soaked in cold water for 2-
3 minutes so enabling separation. Subsequent dehumidification of the membrane can again be carried out.
It was found that the image had been transferred from the plotting paper to the membrane sheet in a highly stable and attractive manner, with high density of color. The membrane can then be used as an interlayer in the normal manner.
It has also been found that the system of the preferred embodiment works with many different types of glass interlayer membranes including EN A, PNB, and Cyclone interlayer with the image impregnated into the membrane in a stable and non-destructive manner. This provides for a highly effective form of interlayer and allows for the creation of attractive signs and other products such as shower screens, windows etc. The forgoing describes a preferred embodiment of the present invention. Modifications, obvious to those skilled in the art can be made thereto without departing from the scope of the invention.