Method for producing three-dimensional effect

• US 5,460,679 A
• Filed: 02/03/1994
• Issued: 10/24/1995
• Est. Priority Date: 02/03/1994
• Status: Expired due to Term

• Current Assignee: Meadwestvaco (WestRock Company)
• Original Assignee: Triad Technologies International Incorporated
• Inventors: Abdel-Kader, Alain
• Primary Examiner(s): Barry, Chester T.
• Application Number:
  US08/190,916
• Time in Patent Office: 628 Days
• Field of Search: 156/275.5, 156/302, 156/286, 156/277, 427/510, 427/369, 427/164, 427/282, 427/272, 427/277, 427/164, 430/321
• US Class Current: 156/275.5
• CPC Class Codes: B29C 67/08 Screen moulding, e.g. forcing the moulding material through a perforated screen on to a moulding surface
• CPC Class Codes: B29D 11/00278 Lenticular sheets B29D11/00269 takes precedence
• CPC Class Codes: B41M 1/12 Stencil printing; Silk-screen printing
• CPC Class Codes: B41M 3/06 Veined printings; Fluorescent printings; Stereoscopic images; Imitated patterns, e.g. tissues, textiles
• CPC Class Codes: B44F 7/00 Designs imitating three-dimensional effects
• CPC Class Codes: Y10T 156/1097 Lamina is running length web

Abstract

A method of producing a depth enhanced printed product uses a screen printer. An optic screen of finely spaced lines are formed as a cured emulsion on a mesh silk-screen. A clear gel is extruded through the mesh screen onto the front side of a clear plastic sheet, creating an array of lenses. An image is previously printed on the back side of the plastic sheet using an offset printer. An optic grid of lines are superimposed in the image. The optic grid has a relationship with the lenses to create special effects such as depth enhancement.

Claims

1. A method of forming an optic screen on a clear plastic sheet, comprising:

forming an optic array of lines on a porous mesh screen;

then

placing a clear gel onto the mesh screen and placing the plastic sheet below the mesh screen;

extruding the gel through the mesh screen onto the plastic sheet to coat the gel on the image sheet in the form of the optic array;

then

curing the gel such that the optic array forms a plurality of lenses.

2. The method according to claim 1 wherein the step of forming the optic array of lines comprises:

forming the optic array on photographic film;

coating the mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen.

3. The method according to claim 1 wherein the step of forming the optic array of lines comprises:

forming the optic array on photographic film;

coating the mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen;

then

placing the film and mesh screen within a vacuum chamber and evacuating any spaces between the film and mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen.

4. The method according to claim 1 wherein the step of forming the optic array of lines comprises:

forming the optic array on photographic film;

coating the mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen in an orientation such that none of the lines of the optic array are parallel with any threads of the mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen.

5. The method according to claim 1 wherein the step of forming the optic array of lines comprises:

forming the optic array on photographic film;

coating the mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen in an orientation such that none of the lines of the optic array are parallel with any threads of the mesh screen;

then

placing the film and mesh screen within a vacuum chamber and evacuating any spaces between the film and mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen.

6. The method according to claim 1 wherein the step of forming the optic array of lines comprises forming all of the lines straight, parallel to and equally spaced from each other.

7. The method according to claim 1 wherein the step of forming the optic array of lines comprises forming a first portion of the lines parallel to and equally spaced from each other, and a second portion of the lines parallel to and equally spaced from each other but not parallel to the lines of the first portion.

8. The method according to claim 1 wherein the step of forming the optic array of lines comprises forming a first portion of the lines parallel to and equally spaced from each other, and a second portion of the lines parallel to and equally spaced from each other but more closely spaced from each other than the lines of the first portion.

9. The method according to claim 1 wherein the step of forming the optic array of lines comprises forming a first portion of the lines curved, parallel to and equally spaced from each other, and a second portion of the lines curved, parallel to and equally spaced from each other but not parallel to the lines of the first portion.

10. The method according to claim 1 wherein the steps of placing the plastic sheet below the mesh screen and extruding the gel through the mesh screen comprise:

placing a squeegee on the mesh screen;

placing a cylinder below the mesh screen;

rotating the cylinder and feeding the plastic sheet between the cylinder and the mesh screen; and

moving the mesh screen linearly while holding the squeegee stationary so that the optic array is printed onto the sheet as the sheet and mesh screen move.

11. The method according to claim 1, wherein the viscosity and cure rate of the gel are selected so that each line of the optic array when cured has a curved transverse cross section configuration.

12. The method according to claim 1 wherein the step of curing the gel comprises exposing the plastic sheet coated with the gel to ultraviolet light.

13. A method of forming a depth enhanced print product, comprising:

forming an optic array of lines in the form of a cured emulsion on a porous mesh screen;

printing an image on the back side of a clear plastic sheet, at least a portion of which is provided with an optic line grid which relates to the optic array;

placing a clear polymer gel onto the mesh screen and placing the plastic sheet below the mesh screen;

extruding the gel through the screen onto a front side of the plastic sheet to coat the gel on the plastic sheet in the form of the optic array;

then

curing the gel, with the optic line grid in the printed image relating to the optic array to provide depth enhancement.

14. The method according to claim 13, wherein the step of printing the image on the back side of a plastic sheet comprises:

providing a print of artwork;

separating colors of the artwork into color separation negatives;

superimposing the optic line grid onto at least a portion of at least one of the color separation negatives;

then

making offset printing plates from the color separation negatives; and

offset printing the image onto the back side of the plastic sheet.

15. The method according to claim 13 wherein the step of forming the optic array of lines comprises:

forming the optic array on photographic film;

coating the mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen in an orientation such that none of the lines of the optic array are parallel with any threads of the mesh screen;

then

placing the film and mesh screen within a vacuum chamber and evacuating any spaces between the film and mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen.

16. The method according to claim 13 wherein the steps of placing the plastic sheet below the mesh screen and extruding the gel through the mesh screen comprise:

placing a squeegee on the mesh screen;

placing a cylinder below the mesh screen;

rotating the cylinder and feeding the plastic sheet between the cylinder and the mesh screen; and

moving the mesh screen linearly while holding the squeegee stationary so that the optic array is printed onto the sheet as the sheet and mesh screen move.

17. The method according to claim 13, wherein the viscosity and cure rate of the gel are selected so that each line of the optic array when cured has a curved transverse cross section configuration.

18. A method of forming a depth enhanced print product, comprising:

providing a print of artwork;

separating colors of the artwork into color separation negatives;

superimposing an optic line grid onto at least a portion of at least one of the color separation negatives;

then

making offset printing plates from the color separation negatives;

offset printing an image from the printing plates onto the back side of a clear plastic sheet;

forming on photographic film an optic array of lines which have a relationship with the optic line grid;

coating a mesh screen with a light sensitive emulsion;

then

placing the film adjacent the mesh screen in an orientation such that none of the lines of the optic array are parallel with any threads of the mesh screen;

then

placing the film and mesh screen within a vacuum chamber and evacuating any spaces between the film and mesh screen;

then

passing light through the film to expose the optic array onto the emulsion; and

removing portions of the emulsion which were not exposed to the light, leaving a cured emulsion of the optic array on the mesh screen;

then

placing a clear polymer gel onto an upper side of the mesh screen and placing the plastic sheet with its front side in contact with a lower side of the mesh screen;

mounting a squeegee in contact with the upper side of the mesh screen;

moving the squeegee and the screen relative to each other to force the gel through the screen onto the plastic sheet to coat the front side of the plastic sheet with a clear coating in the form of the optic array;

then

curing the gel to form lenses in the optic array which substantially register with the lines of the optic line grid to provide an enhanced depth.

19. The method according to claim 18 wherein the steps of placing the plastic sheet with its front side in contact with the lower side of the mesh screen and forcing the gel through the mesh screen with the squeegee comprise:

placing a cylinder below the mesh screen;

rotating the cylinder and feeding the plastic sheet between the cylinder and the mesh screen; and

moving the mesh screen linearly while holding the squeegee stationary so that the optic array is printed onto the plastic sheet as the plastic sheet and mesh screen move.

20. The method according to claim 18, wherein the step of forming on photographic film an optic array of lines comprises spacing the lines in the range from 150 to 300 lines per inch.