A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
H
HALF-TONE
The representation of tonal gradation by an image composed of dots of varied sizes, the centers of which are equidistant.
The representation of tonal gradation by an image composed of dots of varied sizes, the centers of which are equidistant.
HALF-TONE SCREEN
A grid in which the lines and spaces are of equal thickness and equidistant used in photographing an original for plate or block making.
HARDWOOD PULP
Pulp obtained from the wood of hardwood trees by various processes. The fibers are generally shorter than those of softwood pulp.
HEAD BOX
Also see Flow Box. An elevated tank or container equipped with an overflow device that, when supplied with excess of a liquid or fluid, can deliver same at a constant hydraulic head to a lower point.
HEAT-SET INK
A printing ink produced to dry by the application of heat after printing.
HOT MELT COATING
A method of coating with a 100 percent solids compound of wax, resin of polymer - or mixtures thereof - heated to a fluid state and applied to the substrate by, for example, a roll, gravure or extrusion process with a subsequent chilling device.
HYDROGEN PEROXIDE BLEACHING
A method in which pulp is bleached in an alkaline environment with hydrogen peroxide, sometimes using oxygen reinforcement. The method considerably reduces the need for chlorine-containing chemicals in the final bleaching of chemical pulps.