A method for realizing, by means of a printing system, an image on a substrate, with application adjacent to said already printed image of an image-integrating material complementary thereto

Description

[0001] A METHOD FOR REALIZING, BY MEANS OF A PRINTING SYSTEM, AN IMAGE ON A SUBSTRATE, WITH APPLICATION ADJACENT TO SAID ALREADY PRINTED IMAGE OF AN IMAGE-INTEGRATING MATERIAL COMPLEMENTARY THERETO.

[0002] The present invention relates to a method for applying, adjacent to an already printed image, an image-integrating material spread over a surface which is complementary to the said image and adapted to confer a special artistic quality on the finished work.

[0003] In the making of printed images, especially in the field of artwork printing, it is know to use very fine metal foil, particularly gold foil, above all as background to the image, sometimes as substrate for the colour, more rarely - and only in pieces of a certain value - to form parts of the image itself.

[0004] If the colour employed is either intrinsically transparent or transparent because the spread layers are of small thickness, it however occurs that the gold background alters the chromatic effect (e.g., a light-blue becomes green).This is of particular importance in four-colour printing when the choice of the four colours presupposes a perfectly white background.

[0005] The technique is also know of gluing metal foil, particularly gold foil, to given areas of the surface of an image, first applying a suitable adhesive by brush or the like, thus manually.

[0006] As well as requiring considerable time, such operating technique perforce does not permit perfect demarcation or coincidence between the glued area and the coloured or inked area, even if enlargers are used as an optical aid. This difficulty of demarcation becomes, moreover, particularly acute when the adhesive or glue requires to be applied over areas which are geometrically very irregular and/or very small, sometimes even puntiform.

[0007] When, with the aforesaid difficulties, the glue or adhesive has been applied and has become tacky, the very fine metal foil, e.g., gold foil, is placed over said areas; when the adhesive has set, the surface formed by the glued metal foil exactly reproduces the same surface area as that of the previously applied glue.

[0008] It follows inevitably that the formed metal-foil surface reproduces the limitations and rough approximations inherent in the above described method for applying the adhesive to the substrate, involving a considerable lack of precision due to interruptions and also overlaps between the areas of colours and/or ink and those covered with metal foil.

[0009] The said manual technique is also very time-consuming.

[0010] Additionally, the repeat of a relatively large number of copies of one and the same work using the manual technique in question is self-evidently a very lengthy process, and thus costly.

[0011] The general object of the present invention is to obviate the aforementioned inconveniences by embodying a method which overcomes the limitations of precision of the known art, applying rapidly and with extreme precision and at any point of an already printed image, at least one image-integrating material, such as a very fine metal foil, e.g., gold foil, which is complementary to the said image.

[0012] To attain this object the method of the present invention, by means of a printing system, realizes an image on a substrate with application adjacent to the printed image of a least one image-integrating material which is complementary to it, characterized in that over at least one pre-determined area of the substrate there is spread, through the agency of a stereotype of said pre-determined area, a layer of adhesive for fixing at least one image-integrating material.

[0013] The preparation of the stereotype for the highly precise location of the pre-determined areas to which it is wished to apply the image-integrating material, e.g., gold foil, can advantageously be carried out with the same technique as is used for preparing screens for screen printing.

[0014] It is in effect known that screen printing consists basically of the following steps:

a) preparing a screen gauze made of a natural or synthetic fibre, of suitable mesh, and fitting it to a suitable frame;

b) producing on the screen the negative (also known as the positive) of the image to be printed, in other words blocking out - either chemically or with suitable substances (crayon waxes) - the portions and/or points on the screen which are not required to be crossed by the colour or ink;

c) laying to screen proximally to the substrate to be printed and transferring the colour or the ink by means of a blade, or squeegee, through the unblocked-out areas of the screen.

[0015] The method most commonly used for performing the operations as at b) above is to prepare the image on a transparent film or diapositive with clearcut and not blurred contours, i.e., such as the so-called photo-mechanical or lithographic type; to adhere said diapositive to said fibre screen gauze impregnated with photosensitive substances; to expose the film or diapositive to UV radiation or strong light for a certain period of time; to remove with a jet of water those areas or points which have not undergone the ensuing photochemical reaction, i.e., those blocked-out on the starting film or diapositive. In this way, the printing negative is formed.

[0016] On the basis of the foregoing, according to a further aspect of the present invention, as preferably applied using screen printing technique, from at least one starting film or diapositive (here designated A) there is formed by contact another film or diapositive (here designated B) of dimensions identical to those of the starting one, but negative, i.e. with the blocked-out areas and points corresponding with the previous transparent areas and vice-versa, thus creating an image perfectly complementary to the first, the blocked-out areas or points of which represent, after transfer onto a screen gauze placed in register with the first print, areas onto which - according to the invention - through the agency of a squeegee or blade - an adhesive is caused to pass, which areas correspond with the areas and points of "non-colour", i.e. not printed in the first print.

[0017] In other words, on superimposing the film A, which represents the image, on the film B, which represents the areas and points intended to receive the adhesive, there are no interruptions and a single, unbroken, blocked-out surface is obtained.

[0018] The same result can be obtained, if the image was traced using crayon waxes or the like, on a screen gauze, superimposing on this another gauze already coated with photochemical emulsion; by effecting the contact by known means and exposing to strong light there is directly obtained a screen gauze with an image complementary to the first and with the transparent or "permeable" areas to be traversed, after placing in register, by suitable adhesive.

[0019] Then, after the time necessary for the adhesive to become tacky, the metal foil is applied.

[0020] When the adhesive has set, removal is made with a jet of water or a brush, of the portions of metal foil on the areas of colour of the print - which areas, for the reasons stated heretofore, are without adhesive.

[0021] In short, when konwn screen printing is employed to produce the work it is wished to create, the screen gauze are prepared for printing with the single or the diverse colour(s) of which the image is composed, and there is also prepared a screen gauze reproducing the areas onto which the image-integrating metal foil is to be applied.

[0022] This last-mentioned screen gauze serves as a stereotype for rapid and maximally precise spreading of a layer of adhesive onto which, after removal of the stereotype, the operator applies the aforesaid metal foil.

[0023] The method according to the invention can be enacted for producing images on practically any kind of substrate, be it fabric, paper, metal, ceramic, wood or the like, and for any end-result, from artwork printing to the printing of clothing and furnishing fabrics.

[0024] The image-integrating material can also be of a wide variety of kinds, including flakes or powder - although, owing to its ductility and malleability, gold foil (or tombac foil) is preferred.

Claims

1) A method of realizing, by means of a printing system, an image on a substrate with application adjacent to the already printed image of at last one image-integrating material which is complementary to it, characterized in that over at last one pre-determined area of the substrate there is spread, through the agency of a stereotype of said pre-determined area, a layer of adhesive for fixing at least one image-integrating material, with the result that there is a perfect coincidence between the outlines of the already printed image and those of the adhesive, even in the case of most complex configurations.

2) A method according to claim 1, characterized in that said printing system is a screen printing system.

3) A method according to calim 1, characterized in that said stereotype is a screen printing screen.

4) A method according to claim 2, characterized in that from at least one starting film or diapositive there is formed by "contact" another film or diapositive of dimensions identical with those of the starting one, but "negative", i.e., with the blocked-out areas and points where the previous transparent zones were, and vice-versa, thus creating an image perfectly complementary to the first, the blocked-out areas or points of which represent, after transfer to a screen gauze placed in register with the first print, areas onto which - by means of a squeegee or blade - an adhesive is caused to pass, which areas correspond with the areas or points of "non-colour", i.e. not printed in the first print, said image-integrating material being placed after a suitable interval of time on said adhesive-spread areas.

5) A method according to claim 2, characterized in that on at least one pre-determined area, not previously printed, of said substrate there is spread through the agency of a screen gauze placed in register with the image and constituting the stereotype of said pre-determined area, an adhesive for fixing the said image-integrating material.

6) A method according to claim 2, characterized in that a diapositive relating to the already printed image is placed in contact with a film to be impressed and then exposed to an appropriate light source for the necessary length of time, thus creating a new image which is negative and thus complementary to the first and which corresponds with the areas and the points to be spread with adhesive for gluing on said image-integrating material, with the result that a perfect coincidence is obtained between the outlines of the already printed image and those of the adhesive, even in the case of most complex configurations.

7-) A method according to claim 2, characterized in that a screen printing screen relative to the already printed image is placed in contact with a screen printing screen to be impressed, exposing it for a sufficient lenght of time to a suitable light source, thus creating a new image, which is "negative" and thus complementary to the first, corresponding to the areas and points to be covered with adhesive for the gluing of the complementary material, so that a perfect coincidence is obtained between the contours of the already printed image and those of the adhesive, even in the case of the most complex configurations.

8) A method according to claim 2, characterized in that use is made of a "negative" diapositive of the already printed image to obtain a screen gauze with permeable areas and points to be traversed by a suitable adhesive for the fixing of said image-integrating material, whereby to saturate the areas and points complementary to the already printed image with said adhesive.

9) A method according to claim 2, characterized in that use is made of a screen gauze featuring the already printed image to obtain another screen gauze which is "negative" of the first, with the permeable areas and points to be traversed by suitable adhesive for the fixing of said image-integrating material, whereby to saturate the complemntary areas and points of the already printed image.

10) A method according to claim 1, characterized in that said image-integrating material is a metal.

11) A method according to claim 1, characterized in that said image-integrating material is a metal foil.

12) A method according to claim 1 characterized in that said image-integrating material is a precious metal foil.

13) A method according to claim 1, characterized in that said image-integrating material is a gold foil.

14) A method according to claim 1, characterized in that said image-integrating material is a tombac foil.

15) A method according to claim 1, characterized in that said substrate is a fabric.

16) A method according to claim 1, characterized in that said substrate is a non-woven fabric.

17) A method according to claim 1, characterized in that said substrate is a paper.

18) A method according to claim 1, characterized in that said substrate is a metal board.

19) A method according to claim 1, characterized in that said support means is a wooden board.

20) A method according to claim 1, characterized in that said substrate is ceramic.

21) A method according to claim 1, characterized in that said adhesive is spread on a plurality of non-printed areas of said substrate.

22) A method according to claim 1, characterized in that said printing system is a screen printing system.

23) A method according to claim 1, characterized in that said printing system is a multicolour screen printing system.

24) A method according to claim 1, characterized in that said printing system is a four-colour screen printing system.