US 4,474,476 A · Chemical printing liquid method and system

Abstract

An improved method and system for properly supplying and mixing printing chemicals and liquid diluent and for supplying the resulting liquid is provided. The method and system feature the use of periodic or continuous monitoring of the ph and/or electrical conductivity level of the printing liquid in a mixing zone to regulate the flow of initial and make-up chemicals to the zone, so that the proper concentration of chemicals is maintained in the liquid. The liquid is at least periodically removed from the mixing zone and make-up diluent is at least periodically added to the mixing zone. The method can be successfully run on a batch, semi-continuous or continuous basis and the system employs an automatic electronic ph and/or electrical conductivity analyzer and signal generator to automatically control signal responsive pumps in the conduit line(s) from the chemical supply zone(s) to the mixing zone. Preferably, automatic liquid level regulating means are provided in the mixing zone, along with an annular drip tube, circulating pump, exit and return lines and the like. The system and method are simple, economical, durable and highly efficient for making up proper levels of printing liquids for offset printing and the like.

Claims14

Dependent claims

An improved chemical blender system for offset printing, said system comprising, in combination:

a. a liquid printing chemical mixing tank;
b. liquid diluent conduit means connected to said tank and automatic liquid level control means in said tank for controlling the ingress of liquid diluent to said tank;
c. liquid pre-mixing means;
d. circulating means for circulating liquid in said tank;
e. at least one container of printing chemical;
and
f. automatic chemical concentration control means, including
i. an automatic signal generating controller,
ii. a ph and/or electrical conductivity probe extending into said tank and connected to said controller and,
iii. pump and conduit means connected to said container and said tank, said pump means also being connected to and actuatable by said controller to meter said chemical into said pre-mixing means in response to signals from said controller for subsequent transmission to said mixing tank liquid whereby, as the liquid in said tank decreases and liquid make-up diluent is added thereto, the concentration of said printing chemical in such tank fluctuates, changing in ph and/or electrical conductivity of the mixed liquid in said tank, said changes automatically causing said controller to generate signals to effect metering of make-up amounts of said chemicals to said pre-mixing means and thereafter to said tank liquid, for adjusting the desired concentration level of said printing chemicals in said tank liquid.

7 more elements

Dependencies are inferred from the claim text.

Chemical printing liquid method and system

Life of this patent

Chemical printing liquid method and system

Life of this patent

Abstract

Claims14