Electrical and Lighting Applications for Dow Industrial Specialty Polymers

Wire, cable, and optical fibers
Gel lacquers for coil coating
Alumina tubes for light bulbs
Fluorescent lighting

Wire, cable, and optical fibers – To assist in assembly and installation operations, POLYOX™ Resins may be used as lubricants for wire, cable, and optical fibers.

CELLOSIZE™ Hydroxyethyl Cellulose polymers are used as water-blocking powders that prevent moisture penetration into broken cables.

Gel lacquers for coil coating – ETHOCEL™ Ethylcellulose resins are a primary component in gel lacquers used to coat generator field coils. Typical gel lacquer formulations are simple – primarily comprised of ETHOCEL Polymer, with a lesser amount of plasticizer, dissolved in an aromatic hydrocarbon-alcohol mixture. The coils are dipped into the solution and receive a uniformly heavy plastic coating.

Alumina tubes for light bulbs

METHOCEL™ A4M Premium Cellulose Ether is used at about 5% by weight as the binder in extruded alumina tubes used in light bulbs. The METHOCEL Cellulose Ether helps hold excellent size and shape tolerances during extrusion, and burns out cleanly upon firing.

Fluorescent Lighting

POLYOX Water-Soluble Resins are widely used in fluorescent lamp production, both as rheology modifiers for phosphor coating suspensions and as binders to adhere the phosphor coating to the glass lamp tube.

POLYOX Water-Soluble Resins provide excellent suspension of phosphor particles, easy and uniform flow, and excellent adhesion to glass tube surfaces. POLYOX Resins do not interact with or adsorb onto phosphor materials. Compared to other organic binders, they also burn off cleanly and quickly at unusually low lehring temperatures. This allows higher luminous output in finished lamps. The thermal decomposition products of POLYOX Water-Soluble Resins are non-toxic.

The POLYOX Water-Soluble Resin is typically dissolved at 2-5% concentration in water. Phosphor is then added to make the phosphor suspension and may be subsequently diluted to either a specific concentration or a final viscosity target (200-300 cp). The final suspension is normally basic in pH (8-10 in China). The glass lamp tube is coated by the phosphor suspension through a downward flow or forced upward flush system.

POLYOX WSR N3000LS is most frequently used in fluorescent lighting applications; POLYOX WSR N750 and WSR 1105 Water-Soluble Resins are also used. These polymers also see utility as phosphor binders in cathode ray tubes.

Typical Fluorescent Lamp Formulation with POLYOX Water-Soluble Resins

Reagent and Concentration Weight in Grams
2% solution of POLYOX WSR N-3000 or WSR N-750 Water-Soluble Resin in deionized water	900
Cool white phosphor	400
TERGITOL™ NP-6 surfactant	0.2-0.80
Triethanolamine	10
SAG 275B (organic defoamer)	0.1
Aluminum oxide (as adhesive additives)

ETHOCEL Ethylcellulose polymers also act as rheology modifiers and binders for coating fluorescent lighting tubes, often in combination with nitrocellulose in systems using solvents such as butyl acetate. The ETHOCEL Polymer is removed by heating. It burns cleanly, leaving no residues, which allows the triphosphor coating to adhere to the glass tube.

CELLOSIZE Hydroxyethyl cellulose is sometimes used in double coat fluorescent lamp systems. The CELLOSIZE polymer may be blended with others such as POLYOX Water-Soluble Resins to improve adhesion of the first phosphor coat so it does not wash off during application of the second coat.