US1604016A - Printing plate - Google Patents

Description

Oct- 19, 1926.

E. A. BORDEN- PRINTING PLATE Filed Dec. 20, 1923 Patented Oct. 1 9, 1926.

EDWIN A. BORDER, OF OAK PARK, ILLINOIS.

PRINTING PLATE.

Application filed December 20, 1923. Serial No. 681,881..

My invention has for its general object the provision of printing plateswhic-h are adapted for the effective and convenient building up or leveling of the printing faces thereof without injury thereto, the plates embodying in themselves structure for the building up or leveling of the printing faces thereof with obvious advantage.

With this object in view my invention consists in certain features of novelty in the construction, combination and arrangement of parts by which the said object and certain other objects, hereinafter appearing are effected, all as fully described with reference to the accompanying drawings and more particularly pointed out in the claims.

In the said drawings- Figure 1 is an enlarged and exaggerated vertical section of a printing plate of my invention under pressure between two pressure members of a press.

Figure 2 is an enlarged partial bottom plan view of the printing plate before the treatment to build up or level the printing face thereof.

Figure 3 is a partial vertical section of the plate as shown in Fig. 2.

Like characters of reference indicate like parts in the several views.

Referring to the drawing an electrotype printing plate is designated at 1 having any printing design on the front or printing face thereof as is usual. This plate has a uniform displacement space providing pattern 2 in the rear face thereof forming a uniform interrupted portion in the form of uniformly spaced apart uniform projections 3 which are preferably tapered and decrease in cross section outwardly to points.

In the treatment of this form of plate to build up or level the printing face thereof it is subjected to pressure between pressure members 4 and 5 of a suitable press, see Fig. 1, whereupon the projections 3 variably displace under the pressure to conform the printing face of the plate with the opposing pressure member 4: of the press, the displace ment space between the projections 3 permitting the displacement thereof and effect ing the building up or leveling of the printing face of the plate wlthout excessive pressure being exerted on any portion of the plate whereby the printing face of the plate is not injured. The variable displacement of the projections 3 is illustrated in Fig. l in which 6 designates an abnormally thick portiouof the plate 1 at which the projections 3 have displaced to a greater extent than at surrounding portions of the plate.

The plate can then be used for printing in which case the crushed and displaced projections 3 serve as the back or seat of the plate, or the back of the plate may be shaved in accordance with the built up or leveled face of the plate to form the back or seat of the plate, the projections 3 being entirely or only partially removed in the shaving. In any case the original thickness of the plate is greater than the desired thickness of the built up or leveled plate when ready for printing. The plate may be built up or leveled on the printing press where as before the original thickness of the plate must be greater than the thickness desired for printing. In this case the pressure exerted by the impression members of the printing press under impression causes displacement of the. projections 3 to build up or level the printing face of the plate and reduce the thickness of the plate to the proper thick ness. It will be observed that where the plate is built up or leveled in the printing press inaccuracies or irregularities in the printing press and the elements involoved in the impression thereof are compensated for in addition to the inaccuracies or irregularities in the plate.

Thus is provided a plate which is adapted for effective, expeditious and convenient building up or leveling of the printing face thereof, and which in its preferred form embraces a complete building up or leveling structure with obvious advantage.

While I have herein shown and particularly described the preferred form of my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made in the details of construction without departing from the spirit of the invention, and I do not wish to be limited to the use of the invention with electrotype plates as the invention is obviously adapted to printing plates other than electrotype plates, but having thus described my invention I claim as new and desire to secure by Letters Patent the following:

1. As an article of manufacture a printing plate having a printing design on the front face thereof and provided with a uniform displacement space providing pattern in the rear face thereof as and for the purposes described. v

2. As an article of manufacture a'printing plate having a printing design on. the front face thereof and provided vvith uniformly spaced apart uniform projections atsth'egrear face as and for the purposes described.

3. As an article of manufacture a print-' ing plate having a printing design on the front face thereof and provided With a displacement space providing pattern at the rear face thereof adapted to displace under 7 pressure to build up or level the printing face of the plate.

i. As an article of manufacture alprinting plate having a printing design on the front face thereof and provided With uniformly spaced apart uniform projections at the rear face thereof adapted to displace under pressure to build up or level the printing face of the plate.

5.v As an article of manufacture a printing plate having a printing design on the front face thereof and provided with uniformly spaced apart uniform projections at v EDWIN'A. BORDEN.

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