1st Silicone Sealant AS-628


1st Silicone AS-628, a one component, high performance industrial grade acetic cure silicone sealant. It offers excellent adhesion, UV resistance and elasticity. AS-628 does not crack or discolor when exposed to harsh elements. It adheres to most materials when used with an appropriate primer to form a durable, flexible, waterproof seal on wet area building materials.

Uses of AS-628 include general glazing of glass, fibreglass, plastics, stainless steel & aluminum, waterproofing of wet area building materials, sealing of small glass tanks and shower screens.

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  • Temperature resistance from -40°C to +200°C
  • Acetic smell
  • With anti-fungus properties
  • Easy universal application
  • Fast skin formation
  • Colourfast and UV-Resistant
  • Suitable for indoor and outdoor


  • General glazing of glass, fibreglass, plastic, stainless steel and aluminium
  • Curtain walls sealing of glass, metal and plastic
  • Suitable sealing of small fish tank, shower screen and window glazing
  • Extremely suitable for sealing of kitchen and air-conditioning ducting system
  • General sealing of sheet metal, skylight and ventilators


Store unopened packages for up to 6 months in a cool, dry storage place between +5°C to +40°C.


Substrate : All usual building surfaces
State of Surface : Clean, dry and grease-free


Minimum Width : 5mm
Maximum Width : 30mm
Minimum Depth : 5mm
Recommendation : 2 x depth = width


Application Method : Applicator gun
Application Temperature : +1°C ~ +50°C
Repair With : 1st SILICONE AS-628


Base : Polysiloxane
Consistency : Stable Paste
Curing System : Moisture Cure
Skinning Time : ca 7 minutes
Curing Time : 1.5mm/24hrs
Hardness  : 28+ 5 Shore A
Shrinking : None
Specific gravity : 1.03 - 1.25
Temperature Resistance : -60°C until + 200°C
Elastic Recovery : >80%
Elongation at Break : >500%
Elasticity Modulus : 0.35 N/mm sq
Maximum deformation : 25%
Maximum tension : 1.50 N/mm sq
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Product Details
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