US1942683A

US1942683A - Printing block and method of making same

Info

Publication number: US1942683A
Application number: US445853A
Authority: US
Inventors: Bert C Chambers
Original assignee: Wallace and Tiernan Inc
Current assignee: US Filter Wallace and Tiernan Inc
Priority date: 1930-04-21
Filing date: 1930-04-21
Publication date: 1934-01-09
Anticipated expiration: 1951-01-09

Description

jan. 9, 1934. i Bl C.. CHAMBERS Iz PRINTING BLOCK AND'METHOD OF MAKING SAME Filed April 21. 1930 INVENTOR Patented Jan. 9, 1934 UNirED STATES rA'rsNr -oi-Flcg PRINTING BLOCK AND METHOD @F MARIN G SAME Application April 2l, 1930. Serial No. 445,853

3 Claims.

My invention relates to printing blocks and methods of making printing blocks.

The object of the invention is to improve the construction of printing blocks useable for example in certain multi-color printing -processes and to facilitate and otherwise improve the method of making printing blocks useable insuch processes.

Other objects will be in part apparent to those skilled in the art or in part pointed out hereafter.

The invention consists in the features of construction, combination of elements, arrangement of parts, and in the method and combination of steps, as will be exemplified in the structure and method hereinafter described, and the scope of the application of which will be indicated in the following claims:

In order that the invention may be readily understood and its advantages from a practical standpoint appreciated, reference may be had to the accompanying drawing showing one of the preferred forms of embodiment `which the printing block of the present invention is adapted to take.

In the drawing, Fig 1 is a plan view of a printing block made in accordance with my invention before incising and stripping; Fig. 2 is a crosssectional view through said block on the line to 2-.2 in Fig. 1; Fig. 3 is the block of Fig. 1 after it has been incised and stripped to print the design shown; and Fig. 4 is a cross-sectional view partly in elevation on the line 4 4 in Fig. 3 looking in the direction of the arrows. The same numerals refer to similar parts throughout.

Referring to the drawing, the printing block there illustrated is generally designated by the letter A and comprises a lead plate l, a layer of fabric 2 cemented on said lead plate, and a thin rubber layer 3 cemented on said fabric so as to be strippable therefrom. The lead plate l and the fabric layer 2 together constitute a supporting base for the layer of rubber 3.

'I'he design to be printed is laid out on the surface of the rubber layer and its outlines are then cut through the rubber layer down to the fabric layer. which are not to be inked or printed from are stripped and removed from the fabric layer ,whereby the design, or other subject matter to beprinted, -standsup in relief from the fabric design vraised'ir'i'V relief on the fabric layer 2, the

Then those portions of the rubber layer,l

(Cl. Mil-395) surface of which is inked or receives the color when used for printing copies in a printing' press. Adjacent to said raised portions' 3a in the drawing are the spaces from which .the rubber layer has been stripped down to the fabric layer and which is at a level suitably below the printing surface of the parts 38 representing the design. v

The part 1 of the printing block maybe made of any suitable non-resilient supporting'I material suchA as wood, lead, etc. Springy material such as sheet steel or copper is preferably avoided. The rubber layer 3 may be applied directly to the, block or plate 1 but I prefer to use an intermediate layer 2 of a substantial but non-rigid or nonhard nature such as two or three-ply canvas with its layers united by rubber-cement or similar material. One advantage of interposing such an intermediate layer between the rubber layer 3 and the metal plate 1 is that the point of the cutting tool is not dulled or turned by the intermediate layer which it would be by the plate when cutting through the rubber layer preparatory to stripping. Another advantage is that the intermediate layer or layers can be cut through as to portions thereof; and stripped from the plate 1 where it is desirable or necessary to give greater depth to the spaces adjacent the printing portions Bi as will be explained later. Moreover, the described portions 2 and 3 may consist of a composite of separable rubber layers on a plate 1, said layers being independently or separately strippable from each other as well as preferably from said plate.

The invention provides a printing block in which the design (meaning design proper, lettering or any other subject matter) can be formed in relief quickly and accurately. The design having been laid out on the surface ofthe rubber layer 3, the rubber layer is cut through with a sharp knife peripherally about the non-printing portions of the rubber layer viz those portions which are not to be inked or printed from. This having been done, 'said non-printing portions are stripped from the intermediate layer thereby leaving in relief the printing portions 3e of the rubber layer.

In case in any given printing block, prepared as above, there is an extra large space or area of exposed intermediate layer between printing 'portions 38L which the sheets being printed might belly into and become smudged by contact with the intermediate layer, this is easily remedied with printing blocks or platesmade up accorde ing to my invention by peripherally cutting through said interfering portion of the intermesaid diiliculty is quickly remedied With'my print-- ing block whereby the printing portions 3 may be caused to stand up with any desired extent of re- Alief by providing multiple strippable layers on the support which can be: cut through and stripped off one after the other according to the extent of relief desired for the printing surfaces of the block.

The'invention is a decided improvement over the existing methods of making up color printing blocks and the like which had a relatively thick rubber layer on a wooden or metal backing and which vrequired the design to be gouged or routed out of the surface portion of the rubber.V This is a considerably longer and more difficult process and not so accurate as the simple procedure permitted by this invention of merely cutting the design through the thin rubber layer to the intermediate or the next layer, if there be more than one intermediate layer, and then stripping away those parts of the rubber and other layers which are not wanted for printing surfaces inthe finished block or which would otherwise interfere with the proper use of the block.

Rubber is the preferred material for the printing layer 3, but it is possible to substitute for it an equivalent material which will properly receive and print colors and vwhich can be readily out through and stripped.

It will be understood that this invention is not limited to the preferential embodiment but that modifications may be made in said embodiment and in the described method without departing from the scope and spirit -of the invention.

What I claim isz- 1. The method of preparing a printing block or plate that has a rubber layer strippably secured to an intermediate layer, which is in turn strippably secured on a substantially rigid base, which method comprises cutting through the rubber layer down to the intermediate layer periphorally about the non-printing portions of the rubber layer; stripping off said portions from the intermediate layer so as to leave in relief thereon the printing portions of lthe rubber layer; and

vcutting through the exposed intermediate layer peripherally about those portions thereof which it is desirable'to remove and stripping of'same'.

2. The method of preparing a printing block or plate having a design delineated thereon in relief between relatively large and relatively small nonprinting areas, and having a rubber layer strippably secured to an intermediate layer, which in turn is secured to a substantially non-resilient base,: which method comprises'cutting through the rubber layer down to the intermediate layer peripherally about the non-printing areas, and

'cutting also through the intermediate layer peripherally about the relatively large non-printing areas, and stripping and removing said portions from the respective-layers so as to leave in relief thereon thev printing portions of the rubber layer.

3. The method of preparing a printing block or plate having a design delineated thereon in reliefv between relatively large and relatively vs'mall non-printing areas, and having a plurality of resilient layers strippably secured to each other and to a substantially non-resilient support, which method comprises' cutting through the outer layer peripherally about the design and stripping all the non-printing areas thereof from the adjacent layer, and then cutting through the said adjacent layer about the relatively large nonprinting areas only and stripping the said adjacent layer from its support at those areas.

BERT C. CHAMBERS'.