CA1264001A

CA1264001A - Method and apparatus for recycling ink

Info

Publication number: CA1264001A
Application number: CA000492868A
Authority: CA
Inventors: Jerry Zucker
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-10-11
Filing date: 1985-10-11
Publication date: 1989-12-27

Abstract

METHOD AND APPARATUS FOR RECYCLING INK

Abstract of the Disclosure Excess or unused ink that is recovered from a printing process and which contains fibrous impurities is recycled by mixing the recovered ink with virgin ink, heating the mixture to decrease the viscosity thereof, and then straining and filtering the heated mixture.

Description

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Background of the Invention In normal newsprintor other printing operations, an excess of printing ink must be employed, and such excess becomes contaminated with lint and other foreign materials.
While it would be desirable -to recover and reuse such excess ink, the lint and o-ther solid contaminants mus-t first be removed. Because of the high viscosity of the recovered ink, however, normal filtering methods canno-t be employed.
Summary of -the Invention The present invention provides a method and apparatus for successfully recycling printing inks in an economical and efficient manner. A volume of the used, lint-containing ink is firs-t mixed with a larger volume of virgin or unused ink, and the mixture is -then heated and agitated to lower the viscosity significantly. The heated mix-ture is -then passed through a filter means to remove the contaminan-ts, whereupon the ink may be recycled.
The Drawing The Figure is a side view of the apparatus of -the present invention.
Description Of The Preferred Embodiment .
As illustrated in the Figure, the apparatus comprises a drum or tank 10 supported in a raised position by a suitable support framework 12. A propeller mixer 14 is disposed in the tank 10 and is driven by a motor 16 supported on the framework 12, Means are provided for heating the tank 10, such as a thermos-tat controlled heater 18 surrounding the drum 10 so as to heat the contents thereof.

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The bottom of the drum 10 is equipped with a valve 20 enabling discharge of the conten-ts of the drum. Valve 20 is connected to a line or pipe 22 to which is connected, in series, a s-trainer 24, a pump 26, a pressure sensing device 28, and a series of filters such as 30, 32 and 3~. The filters may be followed by a three-way valve 36 connected to a return hose 38 and a recirculating pipe 40 leading back to the -tank.
The s-trainer 24 may be of the conventional screen type and is inser-ted upstream of the pump 26 to remove large foreign particles prior to en-try of the recycled ink into the pump. The pressure sensing device 28 is preferably equipped with a pre-set limit and connected to an alarm device (not shown) that will be activated i~ -the line pressure exceeds a predetermined limit, which would occur if the fil-ters were clogged. A pressure guage 42 may also be included -to visually indica-te line pressure.
The filters 30, 32 and 34 preferably contain replace-able filtering,elements, such as bag-type elements. Although a single filter may be employed, it is preferable to employ a series of filters having progressively décreasing mesh sizes from filter 30 to filter 34, thereby removing the finest contamir.ants at the last fil-ter 34.
In order to use the apparatus -to recycle ink, a quantity oE the impurity-containing ink is first introduced into the tank 10. A quantity of new or virgin ink is also intro-duced at this time. Preferably, the quan-tity of virgin ink introduced will be greater than the quantity of used ink.
The virgin ink will typically contain a black pigment,

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The mixture in the tank is then agitated with the mixer 14 while heating with the element 18. The final temperature of the tank will preferably be in the order of 150 to 200 degrees F. Heating and agitation is continued until a uniform color is obtained and until the hea-ted mixutre has a reduced viscosi-ty.
The heated mixture is then purified by opening the valve 20 and operating the pump 26 to cause flow from the tank 20 and -through strainer 24, followed by pressurized flow through fil-ters 30-34. All or a portion of the purified ink, if desired, may be recycled through the return line 38 back to -the tank, or the mixture may be delivered to a holding tank through hose 40.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Method for recycling used printing ink containing impurities comprising the steps of first mixing a volume of the used ink with a greater volume of virgin ink, heating and agitating the mixture to reduce the viscosity thereof, and then removing the impurities from the heated mixture.

2. The method of claim 1 wherein the mixture is heated to a temperature of from about 150 to about 200 degrees F.

3. The method of claim 1 wherein the impurities are removed by passing the heated mixture through a series of progressively finer filters.

4. The method of claim 3 wherein the heated mixture is pumped under pressure through the filters.