US2719481A - Lithographic printing process - Google Patents

Lithographic printing process Download PDF

Info

Publication number
US2719481A
US2719481A US446448A US44644854A US2719481A US 2719481 A US2719481 A US 2719481A US 446448 A US446448 A US 446448A US 44644854 A US44644854 A US 44644854A US 2719481 A US2719481 A US 2719481A
Authority
US
United States
Prior art keywords
plate
printing
lamina
ink
foil
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US446448A
Other languages
English (en)
Inventor
Botthof Charles Laury
Herman J Schultz
Olin E Freedman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DIRECT IMAGE OFFSET Corp
Original Assignee
DIRECT IMAGE OFFSET CORP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to GB12628/53A priority Critical patent/GB727102A/en
Priority to FR1080083D priority patent/FR1080083A/fr
Application filed by DIRECT IMAGE OFFSET CORP filed Critical DIRECT IMAGE OFFSET CORP
Priority to US446448A priority patent/US2719481A/en
Application granted granted Critical
Publication of US2719481A publication Critical patent/US2719481A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C1/00—Forme preparation
    • B41C1/10—Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
    • B41N1/00—Printing plates or foils; Materials therefor
    • B41N1/04—Printing plates or foils; Materials therefor metallic
    • B41N1/08—Printing plates or foils; Materials therefor metallic for lithographic printing
    • B41N1/086—Printing plates or foils; Materials therefor metallic for lithographic printing laminated on a paper or plastic base

Definitions

  • This invention relates to the graphie arts and particularly pertains to improvements in lithographie printing processes.
  • press or printing plates for lithographie presses have been most commonly produced of metallic sheets preferably of zinc or aluminum. These plates were proeessed to produce a grained surface having characteristics enabling the image substance to firmly adhere to the grained surface and enabling the non-image areas of the grained surface to retain suflcient moisture to repel greasy ink and thus keep the plate clean.
  • the most widely employed practice is to place the work or image upon the plate photo-mechanically either by the albumin process or by the deep-etch process, both of which are well known.
  • the albumin process contemplates coating the plate surfaces with an albumin solution containing arnmonium bichromate.
  • the Work is exposed on the plate through a negative and the coatings on those areas which are exposed to the light (the image areas) become insoluble in water, while the coating on the unexposed areas (the non-image areas) remains soluble. Thereafter the solution or coating which remains soluble is washed off and the ⁇ surface from which it is removed becomes receptive to water, while the areas coated by the insoluble solution remain on the plate surface and are receptive to ink.
  • the deep-etch method is similar with the exception that the exposure is through a positive instead of a negative, and the ink receptive image areas are slightly etched by application of a mordant such as ferrie chloride to somewhat flatten the graining over such areas.
  • a mordant such as ferrie chloride
  • the plates produced by the albumin process have a base of ammonium bichromate and albumin underlying the image substance in the image areas, water may attack such base from the marginal edges of the image areas to the detriment of sharpness and opacity of reproduction.
  • Plates produced by the deep-etch process not only lack this disadvantage but possesses the advantage that the image areas are very slightly but evenly depressed with respect to the non-irnage areas due to partial removal of the graining in such image areas by etching, as previously discussed.
  • the plates produced by the above methods are capable of use in either direct or offset printing. It is well accepted that the production of these prior press 2 ,7 1 9 ,48 l Patented Det. 4, 1955 plates is costly from the standpoint of the cost of the materials from which they are produced and the cost of the eight to ten separate steps in the process of their production for use, as well as from the standpoint of the investment in equipment necessary in the photomechanical ⁇ processes of producing the plates.
  • Fig. l is an enlarged diagrammatic illustration in cross section of a plate constructed for use in practicing our invention.
  • Fig. 2 is a diagrammatic illustration of the manner in which the image areas are depressed into the plate and the plate is embossed by such impression.
  • Fig. 3 diagrammatically illustrates the manner of deembossing the plate or returning the irnage areas to a normal printing plane from their depressed position.
  • the press plate construction To practice the present invention, it is essential to provide a laminated plate structure consisting of a lamina of metallic foil and a backing lamina of strong paper or card stock.
  • the metallic lamina is preferably of aluminum foil from one to four thousandths of an inch thick, although any other metallic foil having the characteristics of aluminum foil which are essential in the present process may be used.
  • the above dimensions of thickness are given as an example in that the foil may be of a thickness other than that specified, if so desired.
  • the backing lamina is preferably of a strong tag stock suitably waterproofed by impregnation or coating.
  • the backing lamina is preferably from two to twenty thousandths of an inch in thickness. Obviously, other substances may be substituted for paper or card stock as the backing lamina as well as other thicknesses employed, just so long as the backing has the characteristics essential in the present process.
  • the plate produced as above described is, of course, impervious to or resistant to the penetration of moisture in the amounts to which it may be subjected in use in ordinary lithographie processes. Likewise, it is suflieiently pliable or flexible that it may be mounted on the plate cylinder of a press.
  • the Working surface of the metallic lamina of the plate be grained in order that it will have an affinity for ink and water.
  • This graining is accomplished by dry sand-blasting the working surface to obtain an even, uniform grain.
  • This grain is finer than the smallest half-tone dot or the finest line it is desired to produce, so that smooth, unbroken reproduction of iine screen and line work will result.
  • the grain is of suicient depth to enable it to hold adequate water in the non-image areas to keep the plate clean.
  • a relief form of the material or image is made up asv for letter-press printing.
  • the relief surface of the form is uniformly inked with a greasy ink coating of proper thickness. It is preferable that the ink be entirely free from chemicalV dryers which would tend to harden or glaze the ink to an extent that it would repel rather than attract additional ink.
  • an impression from the relief surface of the form is made upon the grained surface of the plate.
  • the impression upon the press plate can be made in an ordinary letter-press proof press, a cylinder or a platen type printing press.
  • a rm impression In order that areas, type characters, halftone dots, etc., which are to be placed upon the press plate may transfer a full and satisfactory film of ink which will result in satisfactory sensitization of the plate and make it completely receptive to ink, a rm impression, with adequate printing pressure in accordance with the well known methods of letter-press printing, is essential.
  • This impression necessarily disposes the image areas somewhat below the normal printing plane; possibly to a depth of .0015 inch below the grained surface of the plate as an average.
  • the impression will not dispose the image areas at a uniform distance below the grained surface of the plate because even with timeconsuming, expensive make-ready methods, it is impossible to limit the depth of such embossing of the plate to .0015 inch.
  • Fig. 2 of the drawings we have diagrammatically illustrated what we have termed the embossing of the plate effected by impression of the image areas therein, and obviously such impressions and embossing will remain due to the ductile quality of the metallic lamina and the deformable character of the paper backing.
  • the plate is either permitted to stand a short period or is subjected to a warm atmosphere to set the ink on the image areas.
  • the setting may be accelerated by the application of talc.
  • the setting of the ink is to a point short of the point where the grease content of the ink hardens to a degree that it loses its affinity for additional ink.
  • the setting must be sufficient to remove most of the volatile solvent content of the ink.
  • the grained surface of the plate is treated to make the non-image areas more receptive to water and more repellent to ink. This is accomplished by the separate or simultaneous application of a weak acid and gum arabic or equivalent substance.
  • the gum is spread uniformly over the grained' surface ofthe plate to provide a coating which is soluble in water, but notin hydrocarbony or similar solvents.
  • the gum adheres to all metallic areas of the plate, but not the inkcoated image areas. Thereafter, by use of a suitable solvent, the ink may be washed out of the image areas.
  • the depressed image areas are restored to a proper printing plane relative to the non-image areas of the grained surface. This can be accomplished by a swaging action. Excellent results have been obtained by passing the plate between swaging members as illustrated in Fig. 3 of the drawings. It has been found that by such practice, they depressed image areas are restored or repositioned at a proper printing plane at the grained surface, Other methods of accomplishing the latter effect could be employed if desired.
  • the grain will be flattened in the image areas to obtain an effect somewhat like that obtained by the deep etch process.
  • the plate After the plate has been completely prepared, it may be employed to perform all of the functions hitherto performed by prior metallic plates made by prior methods.
  • the original cost of the plate is but a fraction of the cost of prior zinc and aluminum plates.
  • the process of placing the work upon the plate and preparing the plate for use is simpler, and greatly less timeconsuming and, consequently, much more inexpensive than prior methods.
  • no equipment or materials of the type so necessary in photo-mechanical processes are required in this improved process, thus further reducing plate production cost.
  • a process of producing a lithographie printing plate the steps of providing a laminated plate of a lamina of deformable backing materiah, aI lamina of metallic foil having an exposed printing face, impressing an inked relief surface into said printing face to create an inked image area at a distance inwardly of the plane of Said face beyond a proper printing plane relative thereto and thereby forming a set indentation of the image area in the foil lamina and the backing material and correspondingly embossing the backing material in relief at its exposed surface opposite the printing face of the foil lamina, thereafter applying an external force to said plate to deemboss the backing material and force the indented inked image area of the foil lamina to a uniform printing plane relative to the printing face of the foil lamina.
  • a process of producing a lithographie printing plate the steps of providing a laminated plate of a lamina of a backing sheet of paper-like material and a lamina of relatively thin metallic foil having an exposed surface, impressing an inked relief surface into said exposed surtface to create an inked image area at a distance inwardly of the outermost plane of the exposed surface and beyond a proper printing plane relative thereto and thereby forming a set indentation of the image area in the foil lamina and the backing sheet and correspondingly embossing the backing sheet in relief at its exposed surface opposite the foil exposed surface, thereafter applying an external force to said plate to de-emboss the backing sheet and force the indented inked image area of the foil lamina to a uniform printing plane substantially at the foil exposed surface.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Printing Plates And Materials Therefor (AREA)
  • Manufacture Or Reproduction Of Printing Formes (AREA)
US446448A 1951-07-30 1954-07-29 Lithographic printing process Expired - Lifetime US2719481A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
GB12628/53A GB727102A (en) 1951-07-30 1953-05-06 Process for producing a lithographic printing plate
FR1080083D FR1080083A (fr) 1951-07-30 1953-05-16 Procédé d'impression lithographique
US446448A US2719481A (en) 1951-07-30 1954-07-29 Lithographic printing process

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US23941651A 1951-07-30 1951-07-30
US446448A US2719481A (en) 1951-07-30 1954-07-29 Lithographic printing process

Publications (1)

Publication Number Publication Date
US2719481A true US2719481A (en) 1955-10-04

Family

ID=26932553

Family Applications (1)

Application Number Title Priority Date Filing Date
US446448A Expired - Lifetime US2719481A (en) 1951-07-30 1954-07-29 Lithographic printing process

Country Status (3)

Country Link
US (1) US2719481A (fr)
FR (1) FR1080083A (fr)
GB (1) GB727102A (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3095808A (en) * 1960-07-28 1963-07-02 Eastman Kodak Co Photoconductolithography employing rubeanates
US3223032A (en) * 1963-10-04 1965-12-14 Hercules Powder Co Ltd Graining process
US3229628A (en) * 1964-05-22 1966-01-18 Donnelley & Sons Co Printing plate and method of making the same
US3480500A (en) * 1965-05-24 1969-11-25 American Greetings Corp Processes for making debossed decorative metal foil

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE204517C (fr) *
GB189717647A (en) * 1897-07-27 1897-08-28 Christian Scholz Improvements in the Manufacture and Production of Plates for Printing Purposes.
US1100584A (en) * 1912-04-11 1914-06-16 Henry Leitner Means for regulating electric-lamp circuits.
US1149974A (en) * 1914-11-09 1915-08-10 Clifton Chisholm Lithographic plate and the process for producing the same.
US2048964A (en) * 1934-07-05 1936-07-28 Multigraph Co Planographic printing plate
US2104126A (en) * 1934-05-25 1938-01-04 Addressograph Multigraph Planographic printing plate and method of using same
US2216594A (en) * 1938-06-23 1940-10-01 Ditto Inc Duplicating device and a method of producing it
US2276594A (en) * 1939-11-17 1942-03-17 George T Trundle Process of preparing printing members and product thereof
US2302669A (en) * 1941-06-06 1942-11-24 Batcheller Clements Printing plate
US2311047A (en) * 1940-12-06 1943-02-16 William T Hagelin Lithographic plate and process of making the same
US2344510A (en) * 1939-09-01 1944-03-21 Davidson Mfg Corp Planographic plate
US2503679A (en) * 1943-05-07 1950-04-11 Bonding planographic ink
US2516222A (en) * 1945-01-26 1950-07-25 Johnson & Borsell Ab Graining of lithographic and other printing plates

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE204517C (fr) *
GB189717647A (en) * 1897-07-27 1897-08-28 Christian Scholz Improvements in the Manufacture and Production of Plates for Printing Purposes.
US1100584A (en) * 1912-04-11 1914-06-16 Henry Leitner Means for regulating electric-lamp circuits.
US1149974A (en) * 1914-11-09 1915-08-10 Clifton Chisholm Lithographic plate and the process for producing the same.
US2104126A (en) * 1934-05-25 1938-01-04 Addressograph Multigraph Planographic printing plate and method of using same
US2048964A (en) * 1934-07-05 1936-07-28 Multigraph Co Planographic printing plate
US2216594A (en) * 1938-06-23 1940-10-01 Ditto Inc Duplicating device and a method of producing it
US2344510A (en) * 1939-09-01 1944-03-21 Davidson Mfg Corp Planographic plate
US2276594A (en) * 1939-11-17 1942-03-17 George T Trundle Process of preparing printing members and product thereof
US2311047A (en) * 1940-12-06 1943-02-16 William T Hagelin Lithographic plate and process of making the same
US2302669A (en) * 1941-06-06 1942-11-24 Batcheller Clements Printing plate
US2503679A (en) * 1943-05-07 1950-04-11 Bonding planographic ink
US2516222A (en) * 1945-01-26 1950-07-25 Johnson & Borsell Ab Graining of lithographic and other printing plates

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3095808A (en) * 1960-07-28 1963-07-02 Eastman Kodak Co Photoconductolithography employing rubeanates
US3223032A (en) * 1963-10-04 1965-12-14 Hercules Powder Co Ltd Graining process
US3229628A (en) * 1964-05-22 1966-01-18 Donnelley & Sons Co Printing plate and method of making the same
US3480500A (en) * 1965-05-24 1969-11-25 American Greetings Corp Processes for making debossed decorative metal foil

Also Published As

Publication number Publication date
FR1080083A (fr) 1954-12-06
GB727102A (en) 1955-03-30

Similar Documents

Publication Publication Date Title
US3945318A (en) Printing plate blank and image sheet by laser transfer
US2719481A (en) Lithographic printing process
US2205998A (en) Planographic printing plate
US2112416A (en) Type intaglio engraving plates and method for their production
US3245344A (en) Method of making embossed printing plates
JP3255498B2 (ja) グラビアオフセット印刷法
US2248275A (en) Printing plate
US2323752A (en) Photoengraving process and product
US3391637A (en) Makeready method
US2315903A (en) Process of engraving
US2969728A (en) Method of embossing
US1557354A (en) Process for producing photomechanical printing plates
US2020479A (en) Planographic printing element
US3204557A (en) Dry offset printing method
US980290A (en) Process for making printing-plates.
US923799A (en) Process of making pictures.
US1549187A (en) Means for correcting printing plates
US885948A (en) Stereotype.
US1740423A (en) Intaglio offset lithographic plate and process of making same
US1643526A (en) Photo-engraving process
GB866070A (en) Improvements in or relating to printing elements
US3049995A (en) Printing equipment
GB245800A (en) Improvements relating to the production of intaglio printing plates or cylinders
US237664A (en) Method of producing impressions in line or stipple from photographic negatives
US2153597A (en) Printing