Ag-Plus is an enlargement-speed silver-halide photographic emulsion with the highest silver content of any emulsion. Processing is with standard paper developer and fixer. Ag-Plus is non-toxic and contains no phenol or other solvents and can be used safely in any darkoom. The small bottle contains Chrome Alum hardener for making a subbing solution (see below.) Follow these instructions carefully to obtain durable, archivally-permanent prints.

SURFACE PREPARATION
Paper, fabric, rocks, unglazed ceramics usually do not need a pre-coat because they are porous enough to anchor the emulsion, so Ag-Plus can be coated directly onto them. (Unwashed fabrics including raw artists' canvas should be washed and dried before coating.)

Hard materials, metal, plastics, wood, glass, ceramics, need an oil-based pre-coat for good adhesion and to prevent discoloration. For a transparent pre-coat, use glossy polyurethane varnish. For a colored pre-coat, use alkyd primer paint. Both are available at paint and hardware stores. (Oil-base coatings are those whose label says they can be thinned with mineral spirits. Do not use water-base coatings or acrylics, lacquer, shellac, damars, satin finish coatings, etc. which will soften in the developer.) Artist's canvas that has been primed with water-base gesso should be given a topcoat of oil-base varnish or paint.

Glass and glazed ceramics only: A useful alternative for adhesion to glass is a gelatin precoat or traditional photographic "subbing" solution, which fuses the emulsion to the surface. This solution works with mineral-based materials like glass and china, glazed tiles, ceramics and porcelain-- not with plastics, metals, or other hard materials (use polyurethane or paint.) See "Subbing" in Table of Contents.

COATING AND EXPOSING AG-PLUS
Safelight: Use a medium amber, dark yellow, or light red safelight when handling Ag-Plus. Because it is relatively slow, Ag-Plus can tolerate a large amount of safelight brightness and exposure time without fogging. (For maximum safelight output, a low-pressure sodium-vapor lamp with amber filter can be used.)

At room temperature, Ag-Plus emulsion is a solid gel. Before use, plunge the bottle into a container of hot water (130 deg.F or higher) until the emulsion turns liquid. This happens at about 115 deg.F (46 deg.C.) Do not shake the bottle, as bubbles may form. (A microwave oven can be used if care is taken not to overheat the emulsion. Maximum time: 20 to 30 seconds on "high".) The emulsion is uniform throughout, so it is not necessary to melt the entire contents if only a portion is being used. Use containers of glass, plastic, enamel or stainless steel. Plain steel, brass, copper, aluminum and other metals will react with the silver of the emulsion to form black specks.

Apply Ag-Plus with a brush, sponge, paint applicator, paint roller, spray, or by flowing on and draining off the emulsion. If spraying, be sure the spraygun has no brass parts. Dilute the emulsion with warm water if needed. Porous materials need two or more coats. At the same time, coat a few pieces of paper or index cards to serve as test strips for correct exposure.

Increasing speed and contrast: Ag-Plus has normal speed and contrast, but both can be increased by adding a small amount (10 percent) of working developer to the emulsion. Example: add 15 cc's (one tablespoon) of Kodak Dektol working solution to 150 cc's (5 oz.) of Ag-Plus. Be exact on this measurement, using one part of working developer such as Dektol 1 to 2, not the concentrate, to 10 parts of emulsion. Coat the sensitized emulsion mixture the same day it is made up. If it becomes discolored, discard it.

Small areas: The easiest way to coat small pieces is to pour on a surplus of emulsion, spread it quickly with a fingertip and pour the surplus emulsion back in the bottle, leaving enough to make an opaque white coat. After coating, cool air will help to set up the emulsion. Use a fan if available. After a few minutes, the emulsion will set up or become sticky and can be exposed and and developed. Or it can be dried and put away for future use.

Large areas: Keep the emulsion warm in a container of hot water so that it stays liquid as long as necessary. Use a soft brush or other means of spreading it. After the emulsion has been coated, put a fan on it a few minutes, until it becomes sticky, then give a second coat at right angles to the first. Allow the second coat to set up or become sticky, then expose and process it, or dry it and set aside for future use. If dried, it must be dried thoroughly under low humidity and with circulating air, not in a closed box.

Exposing: Ag-Plus exposure varies with age, so differently dated batches may exhibit different sensitivity. A suggested trial exposure time for an enlarger at full aperture is 10 seconds for an 8x10 inch print. Determine the exact exposure with a test strip.

Using a projector: For large prints such as wall murals, artist's canvas and other oversized surfaces when an enlarger does not give enough light, a slide projector can be used. To limit light output and sharpen the image, tape a piece of black paper having an approximately 3/8 inch hole over the front of the projector lens. Or use a polarizing filter. Because of the high light output of a projector, color negatives can also be used to yield black-and-white prints.

PROCESSING AG-PLUS
Develop with paper developer like Kodak Dektol at the recommended working strength of one part developer to two parts of water. Develop in a tray like a conventional print, or if the print is too large, by a sponge or brush liberally wetted with developer. (For large surfaces, even-out development by first wetting the surface with cool water.) For large prints and canvases, a temporary "tray" can be made from a larger-size well-primed stretched canvas containing the processing solutions.

Shortstop: After developing, do not use a water rinse or acid shortstop, which will soften the emulsion. Instead, use a small amount of fixer as a shortstop (worn-out, discarded fixer is okay.) A few seconds in this bath will neutralize the developer.

Fixing: For best results, use a powdered hardening fixer like Kodak Fixer. Avoid liquid or rapid fixers, which can bleach the image and do not effectively harden the emulsion. Fix until all the chalky white areas of the emulsion have turned transparent and it becomes tough and leathery to the touch-- at least 10 minutes. Note: the function of a fixer is to wash away the unused silver compounds; therefore, the fixer should be used generously, with frequent agitation.

Wash ten minutes in cool running water after hardening is complete. Ag-Plus prints wash easily because water easily penetrates the emulsion. A hypo eliminator or hypo clearing agent can be used if desired. After drying, a wrinkled print can be flattened by pressing with a flatiron or dry-mount press on low-heat setting.

Protect the surface only if a harsh environment exists or it will be shown outdoors. Normally, Ag-Plus requires no protective coating. For best protection, coat the dried print with a water- based polyurethane finish. (Do not confuse with the oil-based polyurethane used as a pre- coat. After Ag-Plus has been processed and dried, the choice is much greater and virtually any type of oil, water, or solvent-based finish can be used as a protective finish.)

Adding color: The color and texture of the surface that has been coated are visible through the transparent areas of an Ag-Plus print, so extra colors are often not used. Ag-Plus prints can be toned with conventional sepia or selenium print toners or with Rockland Selectachrome and Printint toners. Ag-Plus can also be hand-colored with artist's oil paints, photographic oils, water-based acrylics, and virtually any other type of paint or coating.

CLEANUP
Ag-Plus emulsion contains no hazardous chemicals and requires no special precautions for use except when spraying. If spraying, use adequate ventilation and wear a respirator. Emulsion that has not been hardened by fixing can be removed from surfaces with hot water. Fixed, hardened emulsion can be dissolved with dilute solutions of household bleach like Clorox or Purex. © Rockland Colloid Corp.

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FA-1® Sensitizer

Rockland Fabric Sensitizer FA-1 is an iron-silver process that produces a silver image of archival quality. The process is similar to that used in the Van Dyke or brownprint process, and can be used with any type of absorbent paper or cloth. It requires a source of bright blue or actinic light for exposure such as sunlight, arc lamps or mercury vapor lamps, plus a full-size negative. The image can be toned with Rockland Selectachrome or other photographic toners.

Obtaining a full-size negative: Formerly, full size negative transparencies could only be made photographically, but technology now offers a method that doesn't need a darkroom-- by digitally making a full-size transparency with an inkjet or laser printer, or photo-copier.

You can start with any kind of original-- a black & white print, color print, black&white negative, color negative, black&white or color slide, digital photograph, or an illustration taken from a book or magazine. You can also start with a drawing or a solid object like a leaf (popular with beginners.)

If you have a scanner or a digital camera, you can scan the image and reverse it to make a black & white negative image, then print this onto transparency material with an inkjet or laser printer. Alternatively, some photo-copiers will scan and reverse an image and print it on transparency material.

If you don't have access to a scanner-printer combination or a photo-copier that can reverse, you can order a full-size negative transparency made from your artwork at an office-service store like OfficeMax or Kinko's.

You may prefer to make a full-size negative the traditional way-- photographically. You can do this by enlarging onto black-and-white litho film. If the litho film is a high-contrast type like Kodalith, develop it in paper-developer like weak Dektol instead of the high-contrast Kodalith developer.

Finally, you can make your own "litho film" by coating Liquid Light or Ag-Plus emulsion onto glass or clear acrylic.

To prepare the stock solutions: FA-1 consists of 3 parts-- iron salts in the green bottle, silver salts in the white bottle, and fixing solution in the large bottle. Caution: The silver salts contain silver nitrate. Avoid getting on the skin or in eyes. Dissolve separately the contents of the iron salts and silver salts, each in one pint (500 cc's) of distilled or deionized water. Dissolve the fixer contents in one quart (1000 cc's) of cool tap water. The stock solutions should be stored in containers of glass, stainless steel or plastic out of the light; do not use other materials. Keep all containers out of the reach of children. Preparation: Under amber or red darkroom safelight or dim incandescent light (excluding fluorescent or daylight), mix equal quantities of the iron and silver stock solutions to make a sensiting solution. Mix only as much as you will need for a period of several days, as the shelf life is limited when the stock solutions are mixed together.

Coating: Use paper that is absorbent, or cloth. Natural fabrics like pure cottton will give better results than synthetics. If using paper, non-sized paper works better than sized. Saturate the material with the made-up sensitizer solution, blot away excess solution and dry in a dark place, preferably with a fan to circulate the air.

Exposure: Expose with sunlight, sunlamp or other actinic light source, using a full-size negative held in contact with the sensitized surface by a pane of single-weight window glass. Usually, 2 to 5 minutes will be the correct exposure; you can watch the image turn brown under the clear portions of the film as exposure takes place. If a brown image fails to appear, remove the negative and slightly dampen the sensitized material by mist-spraying with distilled water, then re-expose.

Development: Place the exposed material under cool running water for one minute. Drain, then place in the fixer solution for 5 to 10 seconds, until the image turns from orange-brown to gray-brown. Do not extend fixing time, or the image will fade. Pour the used fixer back in the bottle for re-use. Rinse thoroughly to remove all processing chemicals. The fabric or paper can then be dried and pressed, if necessary, with a warm iron. Cleaning up: Remove stains from hands by using a dilute laundry bleach followed by some fixer. Bleach plus fixer can also be used to remove an FA-1 image from the material it is printed on. The image can be color-toned with Rockland Selectachrome or other color toners. For other questions, please consult the factory. © Rockland Colloid Corp.

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Liquid Light® Photographic Emulsion

Liquid Light is an enlargement-speed, silver-halide photographic emulsion for making salon-quality prints on any material. Processing is with standard paper developer and fixer. Liquid Light is non-toxic and is unique in containing no phenol or other solvents, and can be used safely in any darkoom. Follow these instructions carefully to obtain durable, archivally-permanent prints.

SURFACE PREPARATION
Paper and fabric do not need a pre-coat because they are porous enough to anchor the emulsion, so Liquid Light can be coated directly onto them. (Unwashed fabrics, including raw artists' canvas should be washed and dried before coating.)

Other materials-- metal, plastics, wood, etc.-- need an oil-based pre-coat for good adhesion and to prevent discoloration. For a transparent pre-coat, use glossy polyurethane varnish. For an opaque pre-coat, use oil-base, or alkyd, primer. Both are available at paint and hardware stores. (Oil-base coatings are those that the label says can be thinned with mineral spirits. Do not use water-base coatings or acrylic gesso, aerosol spray coatings, satin or matte varnishes, artist's oil paints, damar varnish, lacquer or shellac. They may be softened by developer.) Note to artists: If canvas has been primed with water-base gesso, it should be given a topcoat of alkyd primer or glossy polyurethane.

Glass and glazed ceramics only: These also require a pre-coat for adhesion, such as polyurethane, but a better alternative is a gelatin precoat or traditional photographic "subbing" solution, which fuses the photographic emulsion to the glass. Subbing works only with mineral-base materials like glass and chinaware, glazed tiles, ceramics and fired porcelain. Do not use on plastics, metals, or other materials-- use polyurethane. For a guide to the subbing procedure, see "Subbing" in Table of Contents.

COATING & EXPOSING LIQUID LIGHT
Safelight: Use a medium amber, dark yellow or light red safelight when handling Liquid Light. Because it is relatively slow, Liquid Light can tolerate a large amount of safelight brightness and exposure time without fogging. (For maximum safelight output, a low-pressure sodium-vapor lamp with amber filter can be used.)

At room temperature, Liquid Light emulsion is a solid gel. Before use, plunge the bottle into a container of hot water (130 deg.F or higher) until the emulsion turns liquid. This happens at about 115 deg.F or 46 deg.C. (A microwave oven can be used if care is taken not to overheat the emulsion. Maximum time: 20 to 30 seconds on "high".) Do not shake the bottle, as bubbles may form. The emulsion is uniform throughout, so it is not necessary to melt the entire contents if only a portion is being used. Use containers of glass, plastic, enamel or stainless steel; plain steel, brass, copper, aluminum and other metals will react with the silver compounds in the emulsion to form black specks.

Apply Liquid Light with a brush, sponge, paint applicator, paint roller, spray, or by flowing on and draining off the emulsion. If spraying, be sure the spraygun has no brass parts. Dilute the emulsion with warm water if needed. Porous materials need two or more coats. At the same time, coat a few pieces of paper or index cards to serve as test strips for correct exposure.

Small areas: The easiest way to coat is to pour on a surplus of emulsion, spread it quickly with a fingertip and pour the surplus emulsion back in the bottle, leaving enough emulsion to make an opaque white coat. After coating, cool air will help to set up the emulsion. Use a fan if available. After a few minutes, the emulsion will set up or become sticky and can be exposed and and developed. Or it can be dried and put away for future use.

Large areas: Keep the emulsion warm in a container of hot water so that it stays liquid as long as necessary. Use a soft brush or other means of spreading it. After the emulsion has been coated, put a fan on it a few minutes, until it becomes sticky, then give a second coat at right angles to the first. Allow the second coat to set up or become sticky, then expose and process it, or dry it and set aside for future use. If dried, it must be dried thoroughly under low humidity and with circulating air, not in a closed box.

Exposing: Liquid Light exposure varies with age, so differently dated batches may exhibit different sensitivity. A suggested trial exposure time for an enlarger at full aperture is 20 seconds for an 8x10 inch print. Determine the exact exposure with a test strip.

Using a projector: For large prints such as wall murals, artist's canvas and other oversized surfaces when an enlarger does not give enough light, a slide projector can be used. To limit light output and sharpen the image, tape a piece of black paper having an approximately 3/8 inch hole over the front of the projector lens. Or use a polarizing filter. Because of the high light output of a slide projector, color negatives can also be used to yield black-and-white prints.

PROCESSING LIQUID LIGHT
Develop with paper developer like Kodak Dektol at the recommended working strength of one part developer to two parts of water. Develop in a tray like a conventional print, or if the print is too large, by a sponge or brush liberally wetted with developer. (For large surfaces, even-out development by first wetting the surface with cool water.) For large prints and canvases, a temporary "tray" can be made from a larger-size primed stretched canvas containing the processing solutions.

Shortstop: After developing, do not use a water rinse or an acid shortstop, which will soften the emulsion. Instead, use a small amount of fixer as a shortstop (worn-out, discarded fixer is okay.) A few seconds in this bath will neutralize the developer.

Fixing: For best results, use a powdered hardening fixer like Kodak Fixer. Avoid liquid or rapid fixers, which can bleach the image and do not effectively harden the emulsion. Fix until all the chalky white areas of the emulsion have turned transparent and it becomes tough and leathery to the touch-- at least 10 minutes. Note: the function of a fixer is to wash away the unused silver compounds; therefore, the fixer should be used generously, with frequent agitation.

Wash ten minutes in cool running water after hardening is complete. Liquid Light prints wash easily because water easily penetrates the emulsion. A hypo eliminator or hypo clearing agent can be used if desired. After drying, a wrinkled print can be flattened by pressing with a flatiron or dry-mount press on low-heat setting.

Protect the surface only if a harsh environment exists or it will be shown outdoors. Normally, Liquid Light requires no protective coating. For best protection, coat the dried print with a water-based polyurethane finish. (Do not confuse with the oil-based polyurethane used as a pre-coat. After Liquid Light has been processed and dried, the choice is much greater and virtually any type of oil, water, or solvent-based finish can be used as a protective finish.)

Adding color: The color and texture of the surface that has been coated are visible through the transparent areas of a Liquid Light print, so extra colors are often not used. Liquid Light prints can be toned with conventional sepia or selenium print toners or with Rockland Selectachrome and Printint toners. Liquid Light can also be hand-colored with artist's oil paints, photographic oils, water-based acrylics, or virtually any other type of paint.

CLEANUP
Liquid Light emulsion contains no hazardous chemicals and requires no special precautions for use except when spraying. If spraying, use adequate ventilation and wear a respirator. Emulsion that has not been hardened by fixing can be removed from surfaces with hot water. Fixed, hardened emulsion can be dissolved with dilute solutions of household bleach like Clorox or Purex. © Rockland Colloid Corp.

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Liquid Light VC® Variable Contrast Photographic Emulsion

Liquid Light VC is an enlargement-speed silver-halide photographic emulsion for making salon-quality prints on any material. Processing is with standard paper developer and fixer. Liquid Light VC is non-toxic and is unique in containing no phenol or other solvents, and can be used safely in any darkoom. Follow these instructions carefully to obtain durable, archivally-permanent prints.

SURFACE PREPARATION
Paper and fabric do not need a pre-coat because they are porous enough to anchor the emulsion, so Liquid Light VC can be coated directly onto them. (Unwashed fabrics, including raw artists' canvas should be washed and dried before coating.)

Other materials-- metal, plastics, wood, etc.-- need an oil-based pre-coat for good adhesion and to prevent discoloration. For a transparent pre-coat, use glossy polyurethane varnish. For an opaque pre-coat, use oil-base, or alkyd, primer. Both are available at paint and hardware stores. (Oil-base coatings are those that the label says can be thinned with mineral spirits. Do not use water-base coatings or acrylic gesso, aerosol spray coatings, satin or matte varnishes, artist's oil paints, damar varnish, lacquer or shellac. They may be softened by developer.) Note to artists: If canvas has been primed with water-base gesso, it should be given a topcoat of alkyd primer or glossy polyurethane.

Glass and glazed ceramics only: These also require a pre-coat for adhesion, such as polyurethane, but a better alternative is a gelatin precoat or traditional photographic "subbing" solution, which fuses the photographic emulsion to the glass. Subbing works only with mineral-base materials like glass and chinaware, glazed tiles, ceramics and fired porcelain. Do not use on plastics, metals, or other materials-- use polyurethane. For a guide to the subbing procedure, see "Subbing" in Table of Contents.

COATING & EXPOSING LIQUID LIGHT VC
Safelight: Use a light red safelight when handling the emulsion. Because it is relatively slow, the emulsion can tolerate a large amount of safelight brightness and exposure time without fogging.

At room temperature, the emulsion is a solid gel. Before use, plunge the bottle into a container of hot water (130 deg.F or higher) until the emulsion turns liquid. This happens at about 115 deg.F (46 deg.C.) Do not shake the bottle, as bubbles may form. The emulsion is uniform throughout, so it is not necessary to melt the entire contents if only a portion is being used. Use containers of glass, plastic, enamel or stainless steel; plain steel, brass, copper, aluminum and other metals will react with the silver compounds in the emulsion to form black specks.

Apply Liquid Light VC with a brush, sponge, paint applicator, paint roller, spray, or by flowing on and draining off the emulsion. If spraying, be sure the spraygun has no brass parts. Dilute the emulsion with warm water if needed. Porous materials need two or more coats. At the same time, coat a few pieces of paper or index cards to serve as test strips for correct exposure.

Small areas: The easiest way to coat is to pour on a surplus of emulsion, spread it quickly with a fingertip and pour the surplus emulsion back in the bottle, leaving enough emulsion to make an opaque white coat. After coating, cool air will help to set up the emulsion. Use a fan if available. After a few minutes, the emulsion will set up or become sticky and can be exposed and and developed. Or it can be dried and put away for future use.

Large areas: Keep the emulsion warm in a container of hot water so that it stays liquid as long as necessary. Use a soft brush or other means of spreading it. After the emulsion has been coated, put a fan on it a few minutes, until it becomes sticky, then give a second coat at right angles to the first. Allow the second coat to set up or become sticky, then expose and process it, or dry it and set aside for future use. If dried, it must be dried thoroughly under low humidity and with circulating air, not in a closed box.

Exposing: Exposure varies with the age of the emulsion, so differently dated batches may exhibit different sensitivity. A suggested trial exposure time for an enlarger at full aperture is 20 seconds for an 8x10 inch print. Determine the exact exposure with a test strip.

Using a projector: For large prints such as wall murals, artist's canvas and other oversized surfaces when an enlarger does not give enough light, a slide projector can be used. To limit light output and sharpen the image, tape a piece of black paper having an approximately 3/8 inch hole over the front of the projector lens. Or use a polarizing filter. Because of the high light output of a slide projector, color negatives can also be used to yield black-and-white prints.

Using polycontrast filters: The use of variable-contrast filters will allow contrast to be varied between approximately 2.0 (low) and 4 (high). This feature works best if the emulsion is allowed to dry thoroughly before exposure. Without filters, contrast of the emulsion is approximately 2.5 (normal.)

PROCESSING LIQUID LIGHT VC
Develop with paper developer like Kodak Dektol at the recommended working strength of one part developer to two parts of water. Develop in a tray like a conventional print, or if the print is too large, by a sponge or brush liberally wetted with developer. (For large surfaces, even-out development by first wetting the surface with cool water.) For large prints and canvases, a temporary "tray" can be made from a larger-size primed stretched canvas containing the processing solutions.

Shortstop: After developing, do not use a water rinse or an acid shortstop, which will soften the emulsion. Instead, use a small amount of fixer as a shortstop (worn-out, discarded fixer is okay.) A few seconds in this bath will neutralize the developer.

Fixing: For best results, use a powdered hardening fixer like Kodak Fixer. Avoid liquid or rapid fixers, which can bleach the image and do not effectively harden the emulsion. Fix until all the chalky white areas of the emulsion have turned transparent and it becomes tough and leathery to the touch-- at least 10 minutes. Note: the function of a fixer is to wash away the unused silver compounds; therefore, the fixer should be used generously, with frequent agitation.

Wash 10 minutes in cool running water after fixing is complete. Prints wash easily because water easily penetrates the emulsion. A hypo eliminator or hypo clearing agent can be used if desired. After drying, a wrinkled print can be flattened by pressing with a flatiron or dry-mount press on low-heat setting.

Protect the surface only if a harsh environment exists or it will be shown outdoors. Normally, the emulsion requires no protective coating. For best protection, coat the dried print with a water-based polyurethane finish. (Do not confuse with the oil-based polyurethane used as a pre-coat. After Liquid Light VC has been processed and dried, the choice is much greater and virtually any type of oil, water, or solvent-based finish can be used as a protective finish.)

Adding color: The color and texture of the surface that has been coated are visible through the transparent areas of the print, so extra colors are often not used. Prints can be toned with conventional sepia or selenium print toners or with Rockland Selectachrome and Printint toners. They also can be hand-colored with artist's oil paints, photographic oils, water-based acrylics, or virtually any other type of paint.

CLEANUP
Liquid Light VC emulsion contains no hazardous chemicals and requires no special precautions for use except when spraying. If spraying, use adequate ventilation and wear a respirator. Emulsion that has not been hardened by fixing can be removed from surfaces with hot water. Fixed, hardened emulsion can be dissolved with dilute solutions of household bleach like Clorox or Purex. © Rockland Colloid Corp.

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SC-12® Silkscreen Emulsion

SC-12 is a unique screen-making emulsion, having enlargement-sensitivity. It can be used on all natural and synthetic screen materials, and with solvent or water-base inks. Store SC-12 in a cool place, but do not allow it to freeze. Open the bottle only under darkroom safelight, which can be dark yellow, amber or light red. (For maximum light, use a low pressure sodium vapor lamp- consult Rockland.) For long periods of time, as when the emulsion is being dried, total darkness is preferred.

Like any silkscreen emulsion, SC-12 requires the use of positive, “line” artwork. Intermediate or middle tones should be halftone-screened to reproduce accurately. If a 35mm color transparency in an enlarger or projector is used as the image source, it must be of sufficiently high contrast. See the section below on Exposing the Screen.

PREPARING THE DEVELOPER:
The developer is in the labeled bottle It contains caustic soda (Danger: read handling instructions on label Wear rubber gloves and eye protection). Add water to the contents to make one gallon (3785 cc’s) of working solutionl. Store in a tightly-stoppered bottle away from light and heat. Or dilute as needed, one ounce (30 cc’s) of stock solution to one pint (500 cc’s) of water. The developer can be re-used.

COATING THE SCREEN:
At room temperature, SC-12 is a solid gel and should be melted for use by plunging the bottle into a container of hot tap water (140ºF) until a suitable portion becomes liquid. (The emulsion is uniform, so it is not necessary to liquify the entire contents if only a portion is used.). Stand the screen at an angle and pour a ribbon of emulsion onto a squeegee while holding it against the screen. Stroke up to place a thin coat of emulsion on the screen. Put a fan on the screen and let it dry partially, at which time another thin coat can be given. Coat quickly, to prevent the emulsion from setting up or forming a gel prematurely. Coat thinly, to promote light penetration.

When coating is completed, the screen can be stood in a dark place with a fan to speed drying. Dry thoroughly in open air with moderate temperature and humidity and circulating air, not in a closed box The dry screen can be used immediately or stored for future use in a light-proof wrapper.

EXPOSING THE SCREEN:
Screens can be exposed a number of ways with versatile SC-12 emulsion. Screens can be made directly in the process camera, by taping the screen in the film plane where a piece of graphic arts film would customarily be positioned. Screens can be made with an enlarger and a small film positive or high-contrast color positive, instead of the full-size film positive and contact-printing quipment that would normally be used. An opaque projector or slide projector can also be used as a light source. SC-12 can also be exposed by contact-printing, using an enlarger or a 40-watt incandescent bulb at least 4 feet away.

Expose the screen like photographic enlargement paper, onto the coated side of the screen, allowing enough time for the light to penetrate to the base material. A suggested exposure time at full aperture for a screen coated with two thin coats of SC-12 is five minutes. (If in doubt about exposure time, over-exposure is generally okay.)

DEVELOPING & WASHING OUT
Develop in a tray with the re-usable developer that is supplied. A substitute “tray” can be made if needed from a well-primed stretched artist’s canvas large enough to accomodate the silkscreen. Pour in enough developer to flood both sides of the screen and develop with occasional agitation for 2 to 3 minutes. If adequately exposed, the image will appear as a black area on both sides of the screen. (Save the developer for re-use.) Soak or pour on warm water (30°-35°C) to gently wash away the unexposed portions of the screen. Turn on room lights and inspect the screen for satisfactory wash-out.

HARDENING THE SCREEN
Drain the screen and immerse in photographic hardening fixer, preferably Kodak Fixer, a fixer with good hardening action that is available at all photographic stores. Leave the screen in the fixer with occasional agitation, until the surface of the emulsion turns tough and leathery to the touch (about 5 minutes). The screen should then be washed in cool running water for 5 minutes, blotted quickly with newsprint and dried.

TOUCHUP
The exposed areas of SC-12 emulsion can be touched up like a conventional silkscreen emulsion, with glue or lacquer. If any film or scum remains in the unesposed areas, it can be removed by carefully sponging with a solution of one ounce of liquid bleach (Clorox, Purex, etc.) in one quart of cool water. Rinse and dry the screen, which is ready to print with conventional silkscreen inks having either a solvent or water base.

RECLAIMING SCREENS
Dissolve hardened emulsion from screens made of synthetic materials or metal with full- strength household bleach. Screens made of natural fibers (silk, cotton, etc.) will dissolve in bleach, so an enzyme-type emulsion-remover should be used with them. If oil-based ink has been used with a screen, the screen must be thoroughly de-greased and washed with hot washing soda (sodium carbonate) before coating with SC-12 emulsion. © Rockland Colloid Corp.

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