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Top Coats

MacDermid Topcoats are the high performance, multi-function family of coatings engineers worldwide rely on more than ever to protect zinc and zinc-alloy coatings and are particularly suited for automotive applications.

Our Top Coats, including JS, HydroKlad and Torque 'N' Tension, are the most efficient methods to improve performance of any metallic coating, and have become essential ingredients for the next generation of hexavalent-free finishes, capable of ensuring no premature cosmetic corrosion. They offer abrasion resistance, lubrication, UV identifiers, heat resistance, coating deformation protection, color coding, fluid resistance and thread patch adhesion promoters. Ideal for ensuring dissimilar metals remain insulated and isolated, MacDermid Top Coats are the right choice for any application.

Coating advantages

Product Highlights - hydroklad si

MacDermid Topcoats offer these Features

  • Exceptional anti-corrosion performance

  • Predictable torque-tension

  • Compatible with all zinc and zinc-alloy passivates

  • Water, abrasion and heat resistant

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Brake caliperHydroKlad SI offers advantages over organic based sealers including reduced film droplets and direct immersion of galvanized components.

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ProductApplication                              Thermal resistance  Coating typeNote
JS500 Barrel Excellent Inorganic Automotive specified
HydroKlad Si Rack and barrel Excellent Inorganic Brake fluid compatible
HydroKlad SC 40 Rack Good Organic Easy to remove from racks



JS 500

JS 500 improves the corrosion resistance and coefficient of friction properties on most electroplated and mechanical plated parts and threaded fasteners. JS 500 coated zinc finishes are able to replace environmentally hazardous cadmium finishes in many applications. JS 500 is a water-based product which can be incorporated into most plating lines.

Red car macdermid JS500 technical data

When applied over a zinc plated coating (minimum thickness 8um) JS 500 should achieve or exceed 96 hours to first white corrosion and 500 hours to first red corrosion when tested in neutral salt spray to ASTM B117. This corrosion resistance is maintained even after thermal shock testing.

JS 500 can be applied over trivalent-based passivates to give extended corrosion protection. This important factor means that JS 500 can be used easily and economically to give high performance corrosion-resistant coatings free from hexavalent chrome.

The JS 500 process is sold on a license basis to ensure proper application and performance.


HydroKlad Si

HydroKlad 10HydroKlad Si is a clear, inorganic seal for use on electroplated, mechanically plated and galvanised zinc and zinc alloys.

It is an alkaline post dip solution that is chromium-free on initial make-up. It does not contain polymers, which results in reduced droplets compared to conventional organic based sealers. Applied by immersion, it produces a corrosion resistant film particularly when applied over hexavalent or trivalent chromium treated zinc and zinc alloy deposits.

When used as a post dip for galvanised steel surfaces, the thin colorless film increases corrosion resistance and preserves the initial bright appearance of the galvanised surface.

Easy to operate and control, it is highly suited to rack and barrel applications and does not require water rinsing before oven drying.


HydroKlad SC40

HydroKlad SC40HydroKlad SC 40 is a water-based air drying lacquer designed to provide excellent corrosion protection on rack plated zinc and zinc alloy coatings. On Make-up the solution is free from any chromium compounds.

HydroKlad SC 40 coatings improve the gloss level of the passivated coating. In application the coating is designed to minimalize the “last drop” phenomena, giving an even and uniform finish.

HydroKlad SC 40 can be removed from racks in a conventional hot alkaline soak cleaner and is partticularly suitable for rack application.

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 Follow this link for further technical information on our dry flm lubricated Torque 'N' Tension products.