Road Construction Materials


BORNIT® Joint Flex

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quick facts

BORNIT® Joint Flex (Nahtflex®)
Solvent-free, thixotropic (high viscosity) and to -5 °C frostresistant bituminous compound for making flexible and permanent seams when installing asphalt mix in tapes - highly flexible and crack-bridging. Can be applied by hand with a trowel or by machine with the specially developed  working machine BORNIT® Flexomat 3.1. Depending on the machine used to work the compound, layer thicknesses of up  4 mm can be easily applied.

Color: black

4 017228 002903
4 017228 003399
12 liter
25 liter
44 buckets
18 buckets
approx. 0.3 l/lfm for4 cm layer thickness
BORNIT® Joint Flex - 25 liters

detailed information

Areas of application
BORNIT® Joint Flex® is used to provide flexible and permanent seams upon application of asphalt mix lanes (“hot on cold” as well as “hot on hot”) as well as for seams between asphalt surfaces and construction materials with irregular surfaces (milling edges). Main area of application is the mechanical pre-treatment of the centre seam flanks when applying hot mixes.
For cut asphalt edges, using BORNIT® Joint Tape is recommended!

Type and properties
BORNIT® Joint Flex® is a polymer-modified, solvent-free, stable bitumen compound, resistant to frost down to -5 °C. Using BORNIT® Joint Flex®, according to ZTV Asphalt StB 07, highly flexible and permanent seam connections are provided for seams in asphalt road construction. The product is manufactured ready-for-use and is usually applied mechanically with the processing equipment BORNIT® Flexomat 3.1 and Joint Module or, for base and binding layers, with the Edge Module, resp. Layer thicknesses up to 4 mm can also be applied at vertical seam flanks without any problem.

Product advantages
• Solvent-free, thus no impairment of the binding agent in the seam area as with solvent-containing seam adhesives
• Application of the material quantity specified according to ZTV Asphalt-StB 07 in one go (stable up to 4 mm of layer thickness)
• Highly flexible, elastic and good adhesive effect also on slightly moist substrates
• Cost-effective and time-saving machine application
• With BORNIT® Flexomat 3.1 + Edge Module, application of the material for base and binding layers over the entire surface is possible in one go
• Processing and storage possible down to -5 °C

The substrate must be firm, clean and free from oil, grease and ice. Cutting and milling dust must be removed from the seam flanks. The product also adheres to slightly moist (not wet!) substrates. With the substrate being free from ice, processing is possible down to -5 °C.

BORNIT® Joint Flex® is particularly designed for machine processing, but can also be applied with other suitable equipment as well as brush or spatula.
The especially developed processing equipment BORNIT® Flexomat 3.1 (basic unit) as well as the associated add-on modules (Joint Module, Edge Module) enable fast and economic material application for all seam areas in asphalt road construction. Thus, seam treatment over the entire surface with approx. 1,000 m per hour is possible without any problem.
Depending on the application speed (advance) and valve position at the equipment, the material layer thickness to be applied can be varied.
Please request the technical documents for the versatile and easy-to-handle equipment system BORNIT® Flexomat 3.1 separately!
Application of the hot asphalt mix should take place immediately following the application of BORNIT® Joint Flex®. Following application, the seam flank should not be exposed to traffic anymore.

According to ZTV Asphalt StB 07, the required material quantity for the seam treatment is at least 50 g per cm of layer thickness per linear metre of seam flank.

Product data in brief
Type Plastic-modified bitumen emulsion
Base Rubber latex, bitumen emulsion
Solvent None
Colour Black
Density approx. 0.98 g/cm³
Consistency viscous, thixotropic
Application paint brush, spatula, BORNIT® Flexomat 3.1 with joint modul or edge modul
Processing temperature not below - 5 °C
Storage not below - 5 °C
Storage life 12 months if kept closed in original packaging
Cleaning With water if fresh or with BORNIT® MultiClean or BORNIT® Bitumen Cleaner if hardened
Materials harmful to health in terms of the German substances regulation (Arbeitsstoffverordnung) none
Hazard class according to VbF and ADR none
GISBAU product code BBP 10

System products
BORNIT® Flexomat 3.1
BORNIT® Joint Module
BORNIT® Edge Module

In originally sealed containers storable for 12 months. Always close opened containers. Storable down to -5 °C.

Health and fire protection, occupational safety
For information on handling, safety and ecology, please refer to the current safety datasheet.

Forms of delivery
   25 l bucket    ...............................................    18 pcs. per pallet

Note on disposal
Only recycle completely empty containers. Material residues can be disposed of according to AVV-ASN: 080410 (adhesive and sealing compound residues, except for those falling under 080409).

This datasheet replaces any previous technical information about the product. Thus, this information is no longer valid. The details have been compiled according to the latest state of application technology. Please observe, however, that, depending on the state of the construction object, deviations from the method of application suggested in the datasheet may be required. Unless agreed otherwise in individual contracts, any information contained in the datasheet shall be non-binding and thus does not represent an agreed product constitution. We reserve the right to changes in the information contained in this datasheet anytime.


Stock Note


Necessary information – particularly for the use and the use of our products – please refer our brochures. We are at your personal disposal.