Translucent platinum addition silicone for mold making, concrete, and artificial stone

Zhermack HT 33 Translucent is a pourable two-component platinum addition silicone that cures at room temperature into a translucent mold with a Shore A 33 hardness. The mixing ratio is 1:1 by weight. With a tear strength of 20 N/mm and an elongation at break of 460%, the cured silicone is strong and durable, while the translucent mold allows you to see the model inside.

Key advantages

• High tear strength (20 N/mm): resistant to repeated demolding of undercut shapes.
• Shore A 33: firmer than ZA 13 and ZA 22, for molds that need to retain their shape.
• Elongation at break 460%: ample margin during demolding.
• Stable mechanical properties: the cured rubber retains its properties in the long term.
• 1:1 mixing ratio: easy to weigh, no calculations required.
• Translucent: you can see the model through the mold.

Typical applications

• Mold making where dimensional stability and precise reproduction count.
• Jewelry and small precision parts.
• Artificial stone and concrete forms, thanks to good compatibility with concrete formulas.
• Molds for plaster, coatings, polyurethane resins, and acrylic resins.

Processing

1. Shake base and catalyst separately to eliminate sedimentation.
2. Weigh both components 1:1; use a separate spoon for each component. A deviation of up to 5% will not change the end result.
3. Mix vigorously until the color is homogeneous, scraping the bottom and sides.
4. Degas the mixture within the 20-minute working time and preferably pour from a height of about 30 cm.
5. Demold after approximately 3.5 hours at 23 °C. If necessary, use compressed air and avoid sharp objects.
6. Additional pouring can be done within 24 hours: the new layer will bond to the first.

At 40 °C, the working and curing times are approximately halved. At 4 °C, the working time doubles, and curing takes about three times as long.

Technical specifications

Color of base, catalyst, and end product: translucent. Density 1.09 g/cm³. Viscosity approximately 7,500 mPa·s. Working time 20 minutes and curing time 3.5 hours at 23 °C. Hardness Shore A 33 after 24 hours. Tensile strength approximately 6 N/mm², elongation at break approximately 460%, tear strength approximately 20 N/mm. Operating temperature -40 to 200 °C. Typical values after 24 hours of vulcanization at 23 °C, not intended for setting specifications.

Shelf life 18 months when stored between 5 and 27 °C. Do not swap the caps of the base and catalyst.

Produced by Zhermack S.p.A.

Attention: inhibition with addition silicones

This is a platinum addition silicone. Curing can be inhibited by sulfur, nitrogen, and tin compounds, latex gloves, some plastelines, condensation silicones, and certain 3D printing materials. The TDS also warns that some petroleum jellies can hinder curing. When in doubt, perform a small test first. Ensure the surface is clean, grease-free, and dry.