Sika Sikaflex 112 Crystal Clear

Overview: Sikaflex®-112 Crystal Clear is Sika's single-component transparent adhesive and sealant based on silane-terminated polymer (STP / MS Polymer) technology. It cures fully transparent, so the bead is virtually invisible. With strong initial grab, non-sag on vertical surfaces and very low emissions, it works as both an adhesive and a joint sealant — ideal for interior and exterior applications where appearance matters and a visible bead is unwanted.

Key features

• Fully transparent — cures crystal clear, the bead is virtually invisible and does not affect appearance
• Two-in-one — works as both adhesive and sealant, and is CE marked
• Strong initial grab — holds position immediately after bonding, improving on-site efficiency
• Non-sag on verticals — will not slump on walls and soffits
• Very low emissions — passes GEV-EMICODE EC1PLUS and meets LEED v4 requirements
• Wide substrate compatibility — bonds many materials including PVC, broader than typical polyurethane sealants
• STP technology — silane-terminated polymer; easier to overpaint than conventional silicone, and more stable and transparent than polyurethane

Applications

As an adhesive: bonds most building components and materials, including concrete and cementitious substrates, masonry, most natural stone, ceramic tile, timber, metals (aluminium, stainless steel, galvanised steel, powder-coated metals, etc.), glass (non-structural bonding; the bead must not be permanently exposed to sunlight) and PVC.

As a sealant:

• Transparent joints — interior and exterior joint sealing where appearance matters
• Curtain-wall joints — CE marked to EN 15651-1 for curtain-wall joint sealants
• Window/door perimeters — frame-to-wall joints
• Decorative joints — where a visible bead is unwanted

Why choose Sikaflex 112 Crystal Clear

• The transparent option — the fully transparent product in Sika's elastic sealant range; the bead does not affect appearance
• Bond and seal in one — handles both bonding and joint sealing
• Vertical-friendly — non-sag, works on walls and soffits
• Eco certified — EC1PLUS very-low-emission, meets LEED green-building requirements

Substrate preparation

Good cleaning and preparation improve adhesion. Different substrates can use the matching Sika primer/activator: metals (aluminium, stainless steel, etc.) can be wiped with Sika® Aktivator-205; porous substrates (concrete, brick, cement mortar) can be primed with Sika® Primer-3 N; PVC can be primed with Sika® Primer-215. A primer boosts adhesion but does not replace correct cleaning of the substrate. A small adhesion test is recommended before application; refer to the product Technical Data Sheet (TDS) for coverage, preparation and curing details.

Limitations

This product is not suitable for the following — use the appropriate dedicated product instead:

• Weatherproofing or roof sealing
• Permanently submerged joints or joints under water pressure
• Swimming-pool joints, inside or around
• Floor joints or sanitary-grade sealing
• Glass structural sealing such as glass curtain walls, and glass bonding where the bead is permanently exposed to sunlight
• Structural bonding
• Bitumen, natural rubber and EPDM rubber substrates
• Hard-to-bond substrates such as polyethylene (PE), polypropylene (PP) and PTFE (Teflon)

Suspended loads must be combined with mechanical fixings; for natural stone, confirm compatibility with Sika Technical Service first.

FAQ

What is the difference between Sikaflex 112 Crystal Clear and Sikaflex 11FC+?
The main differences are chemistry and appearance: 112 Crystal Clear uses silane-terminated polymer (STP) and cures fully transparent; 11FC+ is polyurethane (PU) and comes in black and grey. Choose 112 for an invisible bead and transparent joints; for general structural bonding and wider joints, 11FC+ is more suitable. Refer to each product's TDS for detailed suitability.

Does Sikaflex 112 Crystal Clear really cure fully transparent?
Yes. It cures to a crystal-clear state with a virtually invisible bead. Long exposure to chemicals, high heat or UV may cause slight discolouration — an appearance change that generally does not affect its technical performance or durability.

Does it need a primer?
It depends on the substrate. Metals can be pre-treated with Sika® Aktivator-205, porous substrates with Sika® Primer-3 N, and PVC with Sika® Primer-215; a small adhesion test before application is recommended.

Most products typically in stock; individual items welcome to enquire. For detailed technical data, coverage and application method, refer to the product Technical Data Sheet (TDS), or WhatsApp Wah Hing.