
About the product
The acrylic that withstands what normal acrylic cannot
Pattex AC 401 is a superior quality plasto-elastic sealant based on acrylic resins in aqueous dispersion. It is a step above standard acrylic: it allows up to 15% service movement compared to the usual 10%, and is suitable for both indoor and outdoor use. It is applied, smoothed with water, and can be painted over. Odorless and solvent-free.
SHORE A 21 AND 350% ELONGATION: it is significantly more flexible than Acryl 1 (Shore A 30). This is why it works in construction joints with medium movement where ordinary acrylic would crack.
Why choose AC 401
- ✓ Paintable: the finish disappears under the paint, without marking the joint or rejecting the roller.
- ✓ Strong adhesion on porous substrates: plaster, gypsum, cellular concrete, brick and exposed brickwork.
- ✓ Indoor and outdoor (except areas with water or permanent humidity).
- ✓ Permanently flexible: does not become brittle over the years.
- ✓ Water-based: odorless, smoothed with soapy water, and tools cleaned with water.
Technical data sheet
| Base | Acrylic resins in aqueous dispersion |
| Drying | By water evaporation |
| Density | Approx. 1.60 g/cm³ |
| Skin formation | 15-30 min (23 °C, 50% R.H.) |
| Drying speed | Approx. 2 mm / 24 h |
| Shore A hardness | Approx. 21 |
| Modulus at 100% (ISO 527) | Approx. 0.2 MPa |
| Elongation at break (ISO 8339) | Approx. 350 % |
| Service elongation | Max. 15% |
| Volume shrinkage | Approx. 14 % |
| Thermal resistance | -25 °C to +80 °C |
| Application temperature | 5 °C to 35 °C |
| Presentation | 300 ml cartridge |
| Storage | 18 months in original packaging, 5 °C to 25 °C |
How many meters does one cartridge yield?
Calculate the yield with this formula, measuring the joint in centimeters:
Linear centimeters = 300 ÷ (width × depth)
Example: a joint 1 cm wide by 0.5 cm deep yields approximately 600 cm, which is 6 meters per cartridge.
Where it is used
Construction joints: fiber cement or tile roofs, concrete and cement, wood-wall, prefabricated partitions and frame-structure sealing.
Carpentry: sealing of interior carpentry and PVC carpentry.
Finishes: wood, baseboards, flooring, trim and electrical boxes.
Repair: cracks, fissures and plaster moldings. Also for installing plaster or polystyrene moldings and panels.
On which substrates
Concrete, cellular concrete, cement, fiber cement, exposed brickwork, prefabricated partitions, tiles, plaster, gypsum, stone, glass, aluminum, PVC carpentry, wood, laminates and polystyrene.
Not suitable for joints in permanent contact with water or high humidity areas (bathrooms, showers, submerged exteriors). For these cases, use a silicone such as Silicon 5 Universal or the SP 101 sealant.
Which Pattex acrylic do you need?
Interior wall crack with little movement? — Acryl 1, more economical and sufficient (up to 10%).
Exposed wood that will be varnished or sanded? — AC 411 Wood, in five shades and sandable.
Joint with more than 15% movement? — SP 101, which reaches 25% and is also paintable.
Bathroom, shower, or contact with water? — Silicon 5 Universal, anti-mold silicone.



















