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[GreenYes] Re: Green Darkroom Parties (was [P2] Green cleaning parties)



I think I found storage ware for your chemicals.  Read this suggestion by Eugene Singer extracted from http://photo.net/large-format-photography-forum/003OsX

"Rubbermaid products are the best ones I have found for storing photo chemicals. The type of plastic they use seems to be thicker, and less permeable to oxygen passage. They make a series of storage bottle-type containers, with screw-on tops. They are available in several sizes, up to one gallon. The top openings are large enough to pour solutions back from a tray without the need for a funnel. They are designed with hand grips, to make them easier to hold. I use them for all types of photo chemical storage. Before screwing the top on the bottle, I use a layer of clear stretch wrap over the opening, as an added seal. Stock paper and film developer will last about six months in one of these bottles, before it begins to oxidize. Fixer, stop bath, wash-aid, and selenium toner will last much longer. I label right on the container with a Sharpie felt tip pen. If I want to change the label, I wipe the Sharpie ink off with my wife's non-acetone nailpolish remover. John Schaffer shows a method in his "Basic Techniques of Photography", where he uses 1 liter Rubbermaid containers in a tempering bath for film developing."

Also read posting by Steve Baggett

The following comes from the usenet form rec.photo.darkroom (http://www.photodigital.net/lists/rec.photo.darkroom/subject.html):

I found a table of O2 permeability of various packaging films for food storage. There are similar results, plus some additional materials. They are in the same units shown above:

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Low Density Polyethylene (LDPE): 510 (food wrap, grocery bags) Orientated Polystyrene (OPS): 355 (Styrofoam) Polycarbonate (PC): 300 (eg Lexan) High Density Polyethylene (HDPE): 185 (Milk, juice jugs) Oreintated Polypropylene (OPP): 160 (Margarine tubs) Polyvinylchloride (PVC): 8 (Cleanser bottles) Polyethylene Terephthalate (PET): 6 (Soft drink bottles) Polyvinyldichloride (PVdC): 0.6 (Saran wrap) Ethylene Vinyl alcohol copolymer (EVAC): 0.1 (interior coatings, gasoline containers)

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And here is a list of the recycle codes printed within the recyclable triangle on the bottom of most containers:

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Code 1 PET (Polyethylene/Terephthalate) usually a clear plastic - includes soft drink and beverage bottles

Code 2 HDPE High Density Polyethylene includes milk jugs, detergent, bleach, some water and vinegar containers and plastic bags

Code 3 PVC Polyvinyl Chloride includes some water containers, cooking oil, glass cleaner and liquid wax bottles (usually clear)

Code 4 LDPE Low Density Polyethylene includes plastic bags, bread bags and food wrap

Code 5 PP Polypropylene includes some yogurt and margarine containers, shampoo and syrup bottles

Code 6 PS Polystyrene includes disposable hot and cold drink cups, plastic plates and utensils, fast food clamshells, egg cartons and meat trays

Code 7 OTHER other resins, complex composites and laminates such as drink boxes and squeezable ketchup bottles

For the chemists among us, I forgot to include the following defintion of the O2 permeability "The numbers are in cubic centimeters per 100 square inches in one day for 1 mil(.001") thick film at 24ºC."

I hope it helps.

Nancy
http://greenbeingnancy.blogspot.com/



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