05318172 is referenced by 32 patents and cites 25 patents.

Electromagnetic radiation is projected through various types of plastics materials such as plastic containers. The readings from the electromagnetic radiation transmitters are received by a sensor array. Plural readings are taken from each plastic bottle as it passes under the sensor. The measurements from the sensor array output are then fed into a computer. The materials are then separated into three classes. The first class contains polyvinyl chloride (PVC) and polyethylene teraphalate (PET) containers. The second class contains polypropylene (PP) and natural (primarily milk containers) high density polythylene (HDPE) containers. The third class contains opaque materials such as rigid, mixed color high density polythylene (HDPE) containers, opaque polyvinyl chloride (PVC) containers, opaque polystyrene (PS) containers, and opaque polypropylene (PP) containers. The groups of plastics contained in each of the classes are then separated out using the same or other detection means.

Title
Process and apparatus for identification and separation of plastic containers
Application Number
7/829962
Publication Number
5318172
Application Date
February 3, 1992
Publication Date
June 7, 1994
Inventor
Abdul R Al Ali
Dahran
SA
David R Morgan
Hardin
KY, US
Garry R Kenny
College Grove
TN, US
Agent
I C Waddey Jr
Edward D Lanquist Jr
Mark J Patterson
Assignee
Magnetic Separation Systems
TN, US
IPC
B07C 5/00
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