Mindblown: a blog about philosophy.

Greasing or scumming. This condition occurs when the nonprinting area begins printing to a greater or lesser degree. Ink specks, streaks, or a general dirtiness may appear in the background areas of the print. Often a thickening of the printed characters or a filling of halftones takes place. This results in uneven quality of line […]

Pigments are the solid coloring matter in inks such as black, white, or any of the common colors. It is generally only the pigment which we see when examining printed matter. Pigments furnish contrast with the background and are responsible for many of the specific properties of the inks, such as specific gravity, opacity or […]

Historical sketch. A precise time and place origin of printing ink is unknown. The beginning of modern printing inks can be considered to be writing ink, which was used by the Chinese and the Egyptians as early as 2600 B.C. These early inks consisted of lamp black mixed with animal or vegetable oils. Later, earth […]

Historical note.—Papermaking is an ancient craft. The Chinese are credited with a capability to produce a writing paper from mulberry fibers at the beginning of the Christian era. One of the many skills which Marco Polo became familiar with in China was Chinese ability to produce handmade paper. It is believed that he brought back […]

The principal advantage of offset over other types of printing production is the economy of preparatory operations. The use of paper prints and reproduction proofs instead of engravings and large metal forms affords substantial savings of preparatory time and materials in favor of lithography. There is another advantage in the lithographic process which until recently […]

To accomplish copy preparation efficiently, basic tools and equipment are necessary. The handwork tools are few and relatively inexpensive. Each copy preparer maintains a set of these basic tools for his personal use. Other equipment to be described will list those machines needed to complete the copy preparation workrooms. Preparers use a desk-size work surface. […]

1. THE INK SYSTEM The particular ink required for a job is placed in a trough or fountain which extends the full width of the press. An agitator moving continually across the fountain keeps the ink in a workable condition. Ink which is not worked continuously has a tendency to stiffen. In this condition good […]

MECHANISM The lithographic press consists of many component parts. It is a precision machine which, during manufacture, requires very precise tolerance—in many instances less than 0.0005-inch variation. BROAD CLASSIFICATIONS OF TYPES OF PRESSES There are two general types of machines manufactured: (1) sheet-fed presses and (2) roll-fed presses. The distinction is simple. The sheet-fed press […]

INTRODUCTION Lithographic presswork transfers a continuously inked image from a plane surface by means of a cylinder-mounted metal plate containing the image to a rubber blanket and then to a sheet or roll of paper. Many varieties and thicknesses of paper stock and numerous different colors of ink are needed and used to produce the […]

A bimetal plate usually has an image-forming copper layer plated onto a sheet of aluminum or steel. The processing of these plates removes the image-forming copper in the nonimage areas. This gives an image in very slight relief which is exactly the opposite condition of a deep-etch plate which recesses the image base slightly below […]