FR2713152A1 - Printed sheet esp. for packaging - Google Patents

Abstract

The printed sheet consists of a base layer (2) of a transparent film material with printing (6 - 9; 10, 11) on both sides, positioned so that the printing on one side is partly separate from and partially overlaps the printing on the other. The overlapping portions combine to form parts of the same motif. The overlapping portions of the printing are made with inks which are relatively transparent or dispersed, and the two sets of prints can use different colours. The printed surface on one side of the base layer is covered with a coating of a protective shiny varnish (5), while the opposite surface is covered by a layer of weldable film (3) fixed in place by an adhesive layer (4).

Description

 The present invention relates to a printed sheet. It applies, for example, to flexible sheets intended for packaging food or other products.

 Efforts are currently being made to make packaging more and more attractive. In this context, the invention aims to provide new visual effects giving a certain differential optical depth, or a certain relief effect, to the printed patterns.

 To this end, the subject of the invention is a printed sheet comprising, in at least one region of the sheet, a transparent support film which carries first impressions on its upper face and second impressions on its lower face.

This printed sheet may have one or more of the following characteristics
- At least part of the first impressions is in a location of the support film without printing on its underside, and in that at least a portion of the second impressions is in a location of the support film without printing on its upper side;
at least part of the first impressions is superimposed on at least part of the second impressions;
- when first impressions are superimposed on second impressions, these impressions combine to constitute the same printed pattern;
- When first impressions and second impressions combine to constitute the same printed pattern, first impressions are essentially made up of certain colors of the printed pattern, while second impressions are made up essentially of other colors of the printed pattern;
- When first impressions are superimposed on second impressions, first impressions are essentially made up of relatively transparent and / or raster colors;
- said relatively transparent colors recall colors of the second impressions, with more transparent inks;
- said first impressions are covered with a glossy protective varnish;
- the sheet is delimited, on its lower side, by a weldable film fixed by a layer of glue.

 An exemplary embodiment of the invention will now be described with reference to the accompanying drawing, the single figure of which schematically represents, in section and in exploded form, a region of a printed sheet in accordance with the invention.

 The printed sheet 1 shown in Figure 1, for example for packaging food or other products, comprises a support film 2 of flexible transparent plastic, for example polyester, printed on both sides, a lower film weldable 3 fixed by a layer of continuous glue 4, and an upper layer 5 consisting of a glossy protective varnish.

The printing of the support film is carried out in two stages, preferably in gravure printing, starting for example with the underside or reverse side, in the following manner
In a first pass, a first color 6 is printed, in marked areas. Then, in three subsequent passes, a second color 7, a third color 8 and a fourth color 9 are printed, also in marked areas. The areas marked with each color can of course be either completely distinct from one another, or partially or totally superimposed to obtain the desired color combinations.

 Then, on the upper or front face of the support film 2, several colors are successively printed in marked areas, for example a color 10, then a color 11. Then, the protective varnish 5 is deposited on the assembly.

 I1 only remains to glue the underside of the assembly by means of layer 4, then to fix the weldable film 3 on the latter.

 Thanks to the presence of the relatively thick support film 2 made of transparent plastic, between the lower prints 6 to 9 and the upper prints 10 and 11, a depth or relief effect is obtained for the printed patterns.

 Thus, in the region 12 of the sheet indicated on the drawing, a printed pattern is produced, when looking at the sheet from its upper side, by the combination of back prints 6 to 9 on the one hand, and front prints 10 and 11 on the other hand.

In this case, colors 6 to 9 will be chosen judiciously on the one hand, and colors 10 and 11 on the other hand, so as to obtain the desired effect. We can for example choose colors 6 to 9 more opaque than colors 10 and 11, the latter, relatively transparent, then letting see through them, in the background, colors 6 to 9, which gives an optical effect of relief. However, it would be the same with prints 10, 11 in opaque halftone colors.

 Colors 10 and 11 may also recall colors 6 through 9 with more transparent inks.

 Furthermore, in region 13 of the sheet indicated in the drawing, a complete pattern 6 to 9 has been printed on the back of the support film, at a location 13A of this support film devoid of any front printing, and on the front of the film -support, another complete pattern 10, 11, arranged in a location 13B, offset from the location 13A, devoid of any reverse printing.

In this region 13, when looking at the sheet from its upper side, the two patterns seem to be in different planes, which again gives an effect of depth or relief.

 It should be noted that the protective varnish layer 5 is optional. It can either be deleted or be deposited only on certain identified areas. In addition, if desired, the protective varnish 5 can be structured, at least in certain locations, for example by means of a frame. This structured aspect can be uniform, or else with gradual gradations making it possible to accentuate the modulation of the optical effects obtained.

 It is understood that, during the printing of the back (respectively of the front) of the support film, the number of printing passes may be different from four (respectively of two), and that the lower printing 9 may consist of a solid, especially white.

 The invention also applies to the production of relatively rigid and / or closed packages other than by heat sealing, in which case the layers 3 and 4 can be omitted.

Claims (9)

 1 - Printed sheet (1) comprising, in at least one region of the sheet, a transparent support film (2) which carries first impressions (10, 11) on its upper face and second impressions (6 to 9) on its underside.  2 - Printed sheet according to claim 1, characterized in that at least part of the first prints (10, 11) is in a location (13A) of the support film (2) without printing on its underside, and in that at least part of the second prints (6 to 9) is in a location (13D) of the support film without printing on its upper face.  3 - Printed sheet according to claim 1, characterized in that at least part of the first impressions (10, 11) is superimposed on at least part of the second impressions (6 to 9).  4 - Printed sheet according to claim 3, characterized in that, when first prints (10, 11) are superimposed on second prints (6 to 9), these prints combine to form the same printed pattern.  5 - Printed sheet according to claim 4, characterized in that, when first impressions (10, 11) and second impressions (6 to 9) combine to form the same printed pattern, the first impressions are essentially made up of certain colors of the printed pattern, while the second prints are essentially made up of other colors of the printed pattern.  6 - Printed sheet according to claim 4, characterized in that, when first impressions (10, 11) are superimposed on second impressions (6 to 9), the first impressions are essentially made up of relatively transparent and / or screened colors .  7 - Printed sheet according to claim 6, characterized in that said relatively transparent colors recall colors of second impressions, with more transparent inks.  8 - Printed sheet according to any one of claims 1 to 7, characterized in that said first impressions (10, 11) are covered by a glossy protective varnish (5).  9 - Printed sheet according to any one of claims 1 to 8, characterized in that it is delimited, on its lower side, by a weldable film (3) fixed by a layer of glue (4).