WO2000043219A1

WO2000043219A1 - Structure and preparation of transferable screen tints used in color restoration of pictorial works and polychromed sculpture

Info

Publication number: WO2000043219A1
Application number: PCT/ES2000/000020
Authority: WO
Inventors: Margarita San Andres Moya; José Manuel DE LA ROJA
Original assignee: Universidad Complutense De Madrid
Priority date: 1999-01-20
Filing date: 2000-01-20
Publication date: 2000-07-27
Also published as: EP1323546A1; ES2153766B1; AU2111000A; ES2153766A1

Abstract

The invention relates to the structure and preparation of transferable screen tints used in color restoration of pictorial works and polychromed sculpture. The present invention defines the structure and different methods for preparing transferable screen tints, on the basis of which color restoration and polychromed sculpture are effected, e.g. by pressure transfer and three-color superimposition of the sign images (dots, lines, etc) supported therein. Alternative preparation methods of said transferable screen tints are also described such as silk screening or screen printing methods; computerized methods using light-exposed photosensitive emulsions in contact with halftone negatives and their subsequent processing.

Description

TITLE

Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture.

TECHNICAL FIELD. OBJECT OF THE INVENTION

The present invention relates to the description of an element that makes it possible to transfer images such as transferable web backgrounds, and to the different alternative methods of preparing such transferable web backgrounds: screen printing, computerized and preferably photomechanical. These transferable hatched funds are used in the chromatic reintegration in pictorial works and polychrome sculpture, allowing to obtain notable improvements in relation to traditional reintegration systems in terms of faster technical execution, as well as greater security and objectivity in their development.

BACKGROUND

An image, such as a certain graphic design, arranged on a first carrier substrate, can be transferred to a second substrate.

The first image-bearing substrate is usually articles with a structure of certain characteristics that make it possible to transfer the image they support, with different types of transfer substrates (for example, patents W09835840A1, W09339166A1, W097280T2A1 and W09728974A1).

The image can be obtained on the first carrier substrate, generally a plastic film, by some direct printing methods, such as screen printing, inkyet printing, thermal transfer, xerography or laser printing (for example patents W09518720, W09106042 and W09506567).

For the transfer of the image on a second substrate, there are different methods, such as by moisture transfer (for example US3065120), based on the water solubility of certain strata and the insolubility of the image areas to be transferred. There is also the transfer of images through the use of pressure sensitive adhesives (for example, US3276933, US3574049 and US3708320). And on the other hand, there is the transfer of images through the application of heat (for example, US3907974 and US3928710).

Transferable hatched funds, considered as a substrate carrying an image formed by a graphic design of points, lines, etc., are used for the chromatic reintegration of pictorial works and polychrome sculpture, as described in Spanish Patent Application No. P9802182; and allow the reproduction of the color to be reintegrated in the lagoons of a work by trichrome transfer of the yellow, magenta and cyan colors, in their corresponding percentages, previously identified in some reference color tables.

The development of these transferable hatched funds for this defined application entails a series of specific technical requirements, which makes their obtaining differ from other developed image transfer procedures, such as for example the decals or other transfer systems by pressure or temperature. Thus, in the aforementioned systems, the transfer of the image is carried out as a whole and in a single layer on the receiving substrate, however, the image of signs of the transferable hatched backgrounds that offers the possibility of being able to be transferred partially or fragmented without dragging adjacent image areas; and on the other hand, the complete final image is obtained by superimposing three different chromatic layers, corresponding to the colors yellow, magenta and cyan.

EXPLANATION OF THE INVENTION

The present invention relates to the form of elaboration and structure of the transferable hatched bottoms that are used for the chromatic reintegration of pictorial works and polychrome sculpture.

Transferable hatched funds correspond to transferable media that contain the image of dots, strokes or any other sign design valid for application in chromatic reintegration of pictorial work and polychrome sculpture; These sign designs are made in each of the three subtractive primary colors: Yellow, magenta and cyan.

As shown in Figure 1, the structure of transferable funds is divided into two parts: support (1) and image (2).

The support (1) corresponds to a flexible, transparent material with a smooth surface and a thickness of approximately 10OOμ. On the other hand, the image (2) corresponds to the designs of color signs of certain percentages, which will be transferred, by means of pressure in the reintegration process, through pressure sensitive adhesives applied on its surface (3).

The sign designs that present the transferable hatched backgrounds are characterized by their corresponding percentage of signs that expresses the relationship between the area of colored dots or strokes and the part of the free color support. As shown for example in the different designs of signs, specifically of points, of Figure 2, with (4) a design of points of a percentage of 20% is represented; with (5) a design of points with a percentage of 50%; and with (6) a design of points with a percentage of 80%.

For the preparation of these transferable hatched funds, different percentage increases of the chosen signs can be taken, of 5%, 10%, etc .; so that they cover a percentage range of 0% to 90%. Therefore, if percentage increases of 10% are taken, to cover a range of 0-90%, nine transferable funds will be needed (10%, 20%, 30%, 40%, 50%, 60%, 70 %, 80% and 90%) for each primary color: nine for the yellow color, nine for the magenta color and nine for the cyan color.

The designs that constitute the transferable hatched funds are defined according to their lineura, being this, as shown in Figure 3, the number of signs (7) that exist in a certain length measured in the direction of their inclination (8) . Thus, transferable funds can be of different lines, as shown in Figure 4, being able to use the one that best suits the characteristics of the work to be reintegrated.

On the other hand, the sign designs that constitute the plotted funds Transferable, they have different inclinations for each base color, in this way in their superposition to obtain the color to reproduce, the signs of each color tend to be juxtaposed. Preferable inclinations for point designs must maintain a 30 ° inclination difference between successive transferable hatched funds; specifically and preferably, as shown in Figure 5, 15 ° are used for magenta designs (13), 45 ° for cyan (14) and 75 ° for yellow (15).

Obtaining the image of points, lines or any other type of strokes in each of the three yellow, magenta and cyan base colors, on the support can be carried out by different procedures: serigraphic, by conventional screen printing; computerized, using thermal transfer or sublimation plotters; or photomechanical, through the use of photosensitive emulsions exposed to light in contact with hatched negatives, and subsequent processing thereof.

BRIEF DESCRIPTION OF THE CONTENT OF THE DRAWINGS

For the best understanding of what is described herein, some drawings are attached by way of example.

In figure 1, a stratigraphic section of a transferable hatched bottom of a certain percentage of signs is shown. It is represented with (1) the transparent and flexible support that sustains the image of color signs; with (2) the image of color signs (dots, strokes, etc.); and with (3) the pressure sensitive adhesive applied on the image of color signs and which allows it to be transferred.

Figure 2 shows sign designs, specifically of points, with different percentages. It is represented with (4) a design with a percentage of points of 20%; with (5) a design with a percentage of 50% points; and with (6) a design with a percentage of points of 80%.

In figure 3, a design of signs, specifically of points, with a determined lineura is shown. It is represented with (7) the design of the points, specifically of 4 lines per centimeter, corresponding to the number of points in a given length measured in the direction of the inclination (8) thereof; with (8) the 45 ° inclination of the dot design.

In figure 4, different designs of signs are shown, specifically of points, all of them with the same percentage of 30%, but with different lines. It is represented with (9) a design with a linearity of 10 1 / cm; with (10) a design with a line of 5 1 / cm; with (11) a design with a linearity of 3 1 / cm; and with (12) a design with a line of 2 1 / cm.

In figure 5, sign designs with different inclinations are shown. It is represented with (13) a design of points with an inclination of 15 ° corresponding to the magenta color; with (14) a dot design with a 45 ° inclination corresponding to the cyan color; and with (15) a design of points with an inclination of 75 ° corresponding to the yellow color.

In figure 6, a diagram of the arrangement of the mounting elements for exposure to the actinic light of the emulsified support is shown. It is represented by (16) a negative plot; with (17) the emulsified support; with (18) the emulsion of the hatched negative; with (19) the support of the plotted negative; with (20) the support that is emulsified; with (21) the emulsion that is applied to the support; with (22) the actinic light rays; and with (23) a rigid transparent glass or support.

DETAILED EXHIBITION OF AT LEAST ONE MODE FOR CARRYING OUT THE INVENTION

The elaboration of the transferable hatched funds used for the chromatic reintegration of polychrome paintings and sculptures can be carried out by means of different obtaining procedures, which are developed independently in each of the following sections, preferentially treating the procedure Obtaining by photomechanical means.

1.- Obtaining the transferable funds traded by screen printing procedures. The system of printed reproduction, such as serigraphy, allows obtaining transferable screen backgrounds by stamping on the transparent support of transferable screen backgrounds, the image of signs previously created by conventional methods on a screen screen. To obtain the image of signs on the screen printing screen, we start with plotted positives, which can be created by computerized means (by smokers), or by photomechanical means (by high contrast photographic films exposed in contact with contact frames ); with the corresponding characteristics of lineura, percentage and inclination of the signs that the transferable funds must have.

Print the image of signs on the support, and using the same screen screen, a layer of pressure sensitive adhesive is applied on the image, so that it can be transferred.

2.- Obtaining the transferable funds transferred by computerized procedures.

Obtaining the transferable funds transferred by computerized procedures is based on recording the output information through the use of thermal transfer or sublimation printers or plotters. The image of signs (points, lines, etc.) of different percentages, inclinations and linearities, created with the graphic applications currently available in the market, are printed on transparent supports previously treated with a transferable substrate, thus obtaining the plotted funds Transferable from each of the three base colors. It is important to observe the need to use base colors other than those available with these systems in relation to increasing their chromatic stability.

3.- Obtaining the transferable funds processed by procedures photomechanical

Obtaining, by photomechanical means, the transferable hatched bottoms of each of the three base colors, yellow, magenta and cyan, in their different percentages, inclinations and linearities, is based on the use of photosensitive emulsions exposed to light in contact with negatives. hatched, and subsequent processing thereof.

The plotted negatives that contain the image of signs, from which the transferable plotted funds are obtained, can be created by computerized means, by smokers, or by photomechanical means, by high contrast photographic films exposed to different exposure times through contact frames.

These plotted negatives are of high contrast in black and white, and their structure consists of a transparent support and on which an image of signs with sufficient opacity is arranged to prevent the passage of light through it. On the other hand, the photosensitive emulsion used for the preparation of transferable hatched funds is made from dichromated emulsions, whose fundamental components are a colloid and a sensitizer.

The colloid can be of different origins: animal (gelatin, fishtail, albumin, casein, etc.), vegetable (gum arabic) or synthetic (polyvinyl alcohol). The sensitizer can also be of different types: potassium dichromate, ammonium dichromate, sodium dichromate, or a mixture of chromic acid and pyridine or leino quino.

In addition to these main components, colloid and sensitizer, other additives such as plasticizers, bactericides, dyes and surfactants are part of the photosensitive emulsion. Specifically preferably, glycerin and sucrose are used as plasticizers; as bactericides, phenol; as colorants, organic synthetic pigments of each of the three base colors, cyan, magenta and yellow (phthalocyanine blue, dimethyl quinacridone and monoazoic compound, respectively); and a surfactant such as Triton ^® (X-100). Preferably for the development of photosensitive emulsions from gelatin-based colloid, and using ammonium dichromate as a sensitizer, proceed as follows.

An aqueous solution of gelatin [4.3% (w / w)] is prepared, which once hydrated is heated until its complete solubilization. Once dissolved, the surfactant (Triton ^® X-100 [0.2% (w / w))), the plasticizers (sucrose [3.3% (w / w)], glycerin [2.2% ( p / p)]), the corresponding coloring agent, either magenta, cyan or yellow, (magenta [3% (w / w)], cyan [1.7% (w / w)], yellow [1,7 % (w / w)]) and the bactericide (phenol [0.2% (w / w)]), stirring the system until a homogeneous preparation is obtained. To this preparation of colored gelatin, the sensitizer [0.4% (w / w)] is added, homogenizing the system again with stirring.

The solution thus prepared is applied on the transparent support so that a homogeneous layer is left.

Once the transparent support is emulsified with the elaborated emulsion, and it dries, it is exposed to light in contact with the negative hatched as shown in Figure 6. For this, the emulsified support (17) is placed in contact with the negative screen (16), so that the emulsion of the negative screen (18) is in contact with the support (20) that supports the emulsion (21) applied; both components (emulsified support (17) and negative screen (16) are put in intimate contact to ensure a reliable reproduction of the negative sign design, for this purpose it is possible to assemble both components between two crystals (23) on the that pressure be exerted, or placed in a pneumatic press.

Arranged, the negative screen (16) and the emulsified support (17), in the manner described, the emulsified support (17) is exposed to an actinic light (22) through the negative screen (16).

Once the exposure is finished, the emulsified support is revealed in a hot water bath [45 ° C], in which the parts where the actinic light has not affected and that remain soluble are eliminated, and the parts where the actinic light and insolubilized affected , will remain; the final result once the development is finished It will correspond to a positive image of signs with respect to the negative screen used, and the base color, yellow, magenta or cyan, added to the photosensitive emulsion in its preparation.

Once the development is finished, the support with the image of signs is washed in running water. Subsequently, in order to hydrolyze the image of signs, so that subsequently their transfer can be carried out in a timely manner without dragging adjacent signs, the image is subjected to an enzymatic bath in an aqueous solution of papain [0.6% during 60 minutes]. Finally, and once the image dries, a pressure sensitive adhesive solution [50% microcrystalline wax in xylene] is applied thereto, so as to allow its subsequent transfer.

In the described manner, the transferable hatched funds of each of the three base colors, yellow, magenta and cyan, with their corresponding inclinations to each color, and in their different percentages and linearities will be obtained.

Claims

1.- Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, characterized in that they are transferable supports whose structure is divided into two parts:

-the support of a flexible, transparent material

-and the image represented by designs of signs made in each of the three subtractive primary colors: yellow, magenta and cyan, and whose transfer is carried out by means of pressure-sensitive adhesives that allow the image of signs to be transferred to another surface.

2.- Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, according to previous claim, characterized in that they present designs of color signs of different percentages, determined by the relationship between the area of points or strokes of color and the part of the free color support, as well as different inclinations for each base color, and the possibility of making them with different lines.

3. Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, according to previous claims, characterized in that the obtaining of the image on the support can be obtained by different alternative methods: serigraphic, computerized or photomechanical.

4.- Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, according to previous claim, characterized in that their obtaining by screen printing occurs by means of stamping on a transparent support of the image of previously created signs.

5.- Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, according to claim 3, characterized in that their obtaining by computerized means is produced by the use of printers or plotters of thermal transfer or sublimation.

6. Structure and elaboration of the Transferable Trafted Funds used for the chromatic reintegration of pictorial works and polychrome sculpture, according to claim 3, characterized in that their obtaining by photomechanical means is carried out through the use of photosensitive emulsions exposed to contact light with negative hatches, and subsequent processing thereof.