Patent Application
20100162908
Not Applicable
This invention relates to the field of rubber stamps, particularly to the printing of artistic rubber stamp images.
Handheld rubber stamps have been used for years to imprint words or images onto paper and have become a mainstay of many greeting card artists. Generally, stamping comprises a two-step process; a) apply ink (via an ink pad or roller) to said rubber stamp, and b) press said inked stamp firmly onto paper.
For stamp sizes less than two square inches or so, the transfer process generally provides an acceptable image with relatively-modest applied pressure. However, as the complexity or size of a transferred image increases, several problems are encountered. These are as follows.
Ink coverage, as applied via an ink pad or ink roller, of the rubber stamp may be less-than-complete, thus resulting in a stamped image that is also incomplete or varies unacceptably in density. Said problem results from a number of issues such as ink pad ink distribution inconsistencies, ink roller unevenness (pressure or ink coverage), or a user's own inability to judge the ink coverage of a stamp.
Furthermore, manually-applied pressure to a stamp may be uneven across the total area of a stamp-paper interface, thus resulting in a stamped image density that varies according to local pressure applied. For example, the left side of a stamped image may be lighter than the right side if a user applies more pressure to the right side of the stamp. Manually applying proper pressure, and doing so evenly, across a large stamp often requires much practice or much trial-and-error, thereby requiring large quantities of ink and supplies.
Also, the rubber stamp itself may be uneven across its inking surface, thus the density of applied ink may be proportional to the relative height of the stamp surface to paper used to receive said ink, i.e., an uneven stamp can print an uneven image (with regard to image density). Said problem is exacerbated by the use of large stamps, wherein tight in-plane tolerances must be met over a proportionally large area.
The aforementioned problems are alleviated—at least, in part—by the use of a manually-operated printing press wherein a stamp is inked then subsequently placed in a vise-like apparatus that applies heavy pressure to the stamp-paper interface. This method is, of course, hundreds of years old, and the fundamental practice remains unchanged.
While said printing method works well for professional stampers, many stamping hobbyists cannot afford the often-bulky and precision-made printing press. Although inexpensive versions of printing presses are commercially available, many of these products are prone to image quality issues that are evident with manual stamping methods; i.e., if ink distribution is uneven across a stamp, the resulting stamped image will also be uneven. This is a problem compounded by the use of large or complex stamps.
Some artists have used a simple fold-over method for manually printing small quantities of greeting cards. With said method a stamper; a) folds a blank greeting card in half, b) then places an inked stamp upside-down on a work surface, c) then lightly places the blank greeting card front cover on the top of the inked stamp, roughly aligning the edges of the paper with the edges of the inked stamp, and d) subsequently uses fingertip pressure on the double-thickness paper to transfer the inked image to the greeting card front cover. Although this manual method can ameliorate the problems of uneven stamp surfaces and provide, with practice, a more-consistent image, several problems are encountered; a) re-inking of a stamp—if required to correct a spotty image—is not practical (paper and stamp would likely be misaligned on the second printing), b) the stamped image needs to be roughly the size of the greeting card, otherwise precise positioning (for example, centering a small image on a large card) is difficult, and c) the method is still a get-it-right-the-first-time technique, i.e., if a novice applies too little fingertip pressure or too much, the greeting card may need to be rejected.
Thus, because manual stamping methods (traditional and upside-down) require much practice, and large printing presses are expensive, many stamping hobbyists simply avoid large and complex stamps.
The present invention solves the aforementioned rubber stamp problems with both a novel printing method and printing apparatus as shown in
It is a primary objective of this invention to enable consistent and reliable reproductions of artistic rubber-stamp impressions.
It is a further objective of this invention to achieve the aforementioned objective via a compact, cost-effective device.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
After positioning said stamp against support arm 200, a user subsequently clamps it in place by tightening thumbscrew 204.
Printing of greeting cards is a primary use of this invention, and as such, paper 303 can be pre-creased at its center. Said pre-creasing allows a user to easily lift the image half of paper 303 up and away from the rubber stamp. Said lifting is a prelude to the next step in printing.
Subsequent to a user lifting the image half of the print paper, the rubber stamp image surface 201 is inked. To ease inking, the print paper can be held upright by, for example, a sliding clip (not shown) along the top or front (stamp direction) of arm 300. After inking the rubber stamp surface, a user next lowers paper 303 such that the paper surface gently rests on the inked surface. Next the user applies fingertip pressure to gently press the topside of paper 303 against the inked surface and does so with small sweeping motions until the entire image has been pressed. Said method easily overcomes any unevenness in the rubber stamp surface and generally produces an acceptable printed image. The user can check the quality of said image by again lifting the printed half of paper 303 and looking at the inked image. Because clamp 300 maintains good paper-to-stamp registration, the user can re-ink the rubber stamp as required and re-stamp the paper. Said examination and re-inking process can be repeated as required until an acceptable image is produced. Generally a novice user would start with relatively-light pressure, then work towards heavier pressure where needed. Because re-stamping image alignment is good, a user does not necessarily need to “get it right the first time.”
After a successful printing, the user unlatches and lifts clamp 300, allowing paper 303 to be easily removed. A new, clean sheet of pre-creased paper can then be inserted. Because said print paper is pre-creased and the image half is held upright by the user, any residual rubber stamp ink should not be transferred to print paper until the user is ready for printing.
As this apparatus and printing method are manually intensive, said device is not necessarily applicable to mass-production printing. However, for small-volume artistic stamping, this invention allows reliable reproduction of a wide variety of rubber stamp images-and does so with minimal cost investment. Other embodiments based on the disclosed invention should be readily apparent to those familiar with rubber stamping or the fabrication of small tools.
