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DOWSIL™ 757 weatherproofing sealant for photocatalytic clean glass is a one part, neutral cure, architectural grade sealant. It easily extrudes and cures at room temperature by reaction with moisture in the air to form a durable, flexible rubber seal. This low modulus sealant is specially designed for the weathersealing of most photocatalytic and hydrophilic clean glass surfaces where high movement is anticipated and high weather resistance is required in order to withstand increased temperature and UV radiation.


  • Low modulus.
  • Compliant with ISO 11600 G 25 LM and ISO 11431.
  • Available in a range of colours.
  • Odourless.


  • One part.
  • Neutral-cure sealant.
  • Si-hybrid.


  • Designed for use in direct contact with photocatalytic, hydrophilic and standard glass.
  • Excellent adhesion with typical photocatalytic and hydrophilic glasses as well as standard glass, aluminium, metal, painted and unpainted wood.
  • Pre-approved compatibility with DOWSIL™ SG and IG silicone sealants, e.g. DOWSIL™ 993, DOWSIL™ 895, DOWSIL™ 3362 and DOWSIL™ 3793.
  • Ideal for expansion, connection, perimeter and other movement joints.
  • Very good combination of weather resistance and movement capability.


Available in cartridges of 310 ml.

General information

Low modulus

Compliant with ISO 11600 G 25 LM and ISO 11431

Available in a range of colours


Uniclass 2015 Structural sealant glazing weather sealants (Pr_30_31_76_85)
Specification data
Product Reference

DOWSIL™ 757 Weatherproofing Sealant





Standard product features


- Uncured; as tested at 50% RH and 23°C (73°):

  • Working time: 30 minutes.
  • Skin-over time: 75 minutes.
  • Application temperature range: 5–40°C.
  • Curing time: 7–14 days.
  • Extrusion rate: 600 g/min.
  • Resistance to flow: <1 mm.

- As cured; after 28 days at 50% RH and 23°C (73°):

  • Durometer Hardness, Shore A: 20 points.
  • Elastic recovery: 77%.
  • Tensile stress at 100% elongation: 0.25 MPa.
  • Ultimate elongation at break: 247%.
  • Service temperature range: -30–90°C.