This invention relates to an improvement in a two-component diazotype material comprising a film support and a light-sensitive layer thereon, the light-sensitive layer being composed of at least one polymeric hydrophobic binder, a light-sensitive diazonium salt and a coupler, the improvement that the light-sensitive layer additionally contains at least one resin containing acid groups, which resin has an acid number of at least about 100 and which is derived from the maleic acid or phthalic acid...

Thermal diazotype sheets having substituted imidazoline acid-neutralizers are shown to have shelf stability and short development times.

Light-sensitive diazotype photocopying materials comprising a base such as paper having thereon a precoat containing--in addition to a conventionally employed pigment and a binder--an inorganic water soluble salt of zinc, magnesium, aluminum or cadmium, and a two-component light-sensitive diazotype composition applied as coating to the precoat surface.

This invention relates to a process for diazotype multicolor reproduction using an improved photosensitive material having a continuous thermoplastic resin pre-coated layer.

Diazotizable amines of the general formula ##SPC1## Wherein R is substituted or unsubstituted alkyl, hydroxyalkyl, aryl, or aralkyl, and X is a radical of the formula ##SPC2## Wherein Z is a direct linkage, a divalent atom, or a divalent radical.

Disclosure is made of a light-sensitive diazo coating composition and a light-sensitive diazotype reproduction material comprising a base with at least one coating layer comprising a light sensitive diazo compound, coupling component, a stabilizing acid and salt, and a development accelerating and stabilizing composition of 1,3-dimethylurea with urea or with thiourea, which also improves sensitizing solution compatibility and increases printing speed.

A purging system is provided for reducing and substantially eliminating contaminants, moisture, residual gas and the like from a work station such as, for example, a developer station in which ammonia gas is used for development of diazo type films. The system includes a check valve connected between one end of the developer station and a supply of compressed air, and a 3-way valve connected between the other end of the developer station and a supply of ammonia gas and an ammonia exhaust contain...

An apparatus for the continuous development of a diazotype material with a developer powder in which the developer powder is disposed in a hollow body, such as a rotatable drum, a fine-meshed network having openings smaller in cross-section than the cross-section of the smallest grains of the powder, such as a metal screen, forms at least a part of the walls of the hollow body and a transport device, such as an endless belt, moves the diazotype material relative to and in contact with the side o...

A thermally developable diazotype copying material is manufactured which comprises a supporting sheet and a light-sensitive copying layer coated on said supporting sheet, said layer consisting of a water soluble light-sensitive diazo compound, a water soluble heat fugitive acidic salt (base generating agent) and a water insoluble coupler. Another thermally developable diazotype copying material is also obtained, which is of a similar structure but said copying layer further contains an additiona...

A composition and process for developing diazotype material utilizes a developing liquid comprising a buffered, aqueous solution of an azo-coupling component having a pH between 5.5 and 8 and, as an additive compound, sorbic acid, an alkali metal salt, ammonium salt, or magnesium salt of sorbic acid or mixtures of the same. The process produces a clear copy image more quickly than a process in which the developing liquid does not contain the additive compound and, when the azo-coupling component...