A composition roller is a tool used in

letterpress printing Letterpress printing is a technique of relief printing. Using a printing press, the process allows many copies to be produced by repeated direct impression of an inked, raised surface against sheets or a continuous roll of paper. A worker com ...

to apply

ink Ink is a gel, sol, or solution that contains at least one colorant, such as a dye or pigment, and is used to color a surface to produce an image, text, or design. Ink is used for drawing or writing with a pen, brush, reed pen, or quill. Thicker ...

to a bed of type in a

printing press A printing press is a mechanical device for applying pressure to an inked surface resting upon a print medium (such as paper or cloth), thereby transferring the ink. It marked a dramatic improvement on earlier printing methods in which the ...

. It consists of a cylinder made of a substance known as "roller composition" or simply "composition", a mixture of glue and sugar (in the form of molasses or

treacle Treacle () is any uncrystallised syrup made during the refining of sugar.Oxford Dictionary The most common forms of treacle are golden syrup, a pale variety, and a darker variety known as black treacle, similar to molasses. Black treacle has ...

), with various additives such as

glycerin Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...

depending on the particular recipe. Early recipes also included

gypsum plaster Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "re ...

and

tar Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bit ...

, though these were eventually found unnecessary. 1906 ATF composition hand roller

Before its invention, most inking of printing presses was done by manually pounding the type with

ink ball An ink ball, inking ball, or dabber was a tool used in printmaking and letterpress printing to apply ink to the plate or type to be printed. Ink balls had been used since the dawn of the printing press in the 15th century. In printmaking, they w ...

s, specially treated leather balls stuffed with wool. The difficulty and time involved in making and using ink balls led to various attempts to use cylinders, which could be rolled rather than pounded. Leather rollers (or "skin rollers") were attempted, and were used on the earliest steam-powered

cylinder press A rotary printing press is a printing press in which the images to be printed are curved around a cylinder. Printing can be done on various substrates, including paper, cardboard, and plastic. Substrates can be sheet feed or unwound on a continuo ...

es, yet these did not work as well as the ink balls, and the stitching seam would appear on the printed type. Eventually, a substance was found with the right

adhesion Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can b ...

and elasticity to make suitable cylindrical rollers. Composition for use in inking was developed in England in the 1810s by

Robert Harrild Robert Harrild (1 January 1780 – 28 July 1853) was an English printing pioneer. Harrild was the founder of the business Harrild & Sons, his history is recorded in 'The House of Harrild' by Edward Liveing written in 1949, which gives the c ...

and another individual named Forster; they first used it for making ink balls, though they soon turned to making rollers.

Bryan Donkin Bryan Donkin FRS FRAS (22 March 1768 – 27 February 1855) developed the first paper making machine and created the world's first commercial canning factory. These were the basis for large industries that continue to flourish today. Bryan D ...

was the first to apply the composition roller to machine press. By 1826, they had begun to be introduced to the United States. To make a roller, the ingredients are melted together in a double-boiler kettle. The process is timed to avoid

candy Candy, also called sweets (British English) or lollies (Australian English Australian English (AusE, AusEng, AuE, AuEng, en-AU) is the set of varieties of the English language native to Australia. It is the country's common language an ...

ing the molasses. The mixture is cast into molds around a wooden or metal "stock" or core, which after cooling and seasoning is then hooked onto the handle or printing press. The performance of composition rollers was notoriously subject to their environmental conditions. Composition rollers tend to quickly dry out, shrink, and harden, and as a result are typically stored in sealed cabinets called "roller closets", often with a thin layer ink left on the roller as a form of protection. Glycerin, which has an affinity for moisture, was eventually added to the recipe, yet that in turn could cause trouble in warm humid weather where too much moisture would be absorbed. The mixture itself varied depending on the time of year in which they were made, with winter rollers sometimes melting in summer, and rollers made in the summer becoming brittle in winter. However, composition rollers that hardened or otherwise were unusable could be melted down and recast. By the turn of the 20th century, composition rollers were mass-manufactured by various companies, using machines that could cast several rollers at once, using a mixture containing more glycerin than molasses.

References

{{Letterpress Letterpress printing History of printing

See also

References