Nitoprime 330 - High Performance Flooring Primer

Overview

Nitoprime 330 is a high-performance, water-based primer specifically formulated for use with cementitious flooring systems. Manufactured by Fosroc, this product serves as a critical preparatory coating that seals substrates and ensures optimal performance of subsequent flooring applications.

Product Composition

Nitoprime 330 is a water-based styrene-acrylate copolymer emulsion supplied as a single-component concentrate in white liquid form that dries clear. The styrene-acrylate copolymer emulsion provides the product with its specific performance characteristics essential for flooring applications.

Supply Formats and Product Codes

The product is supplied in three convenient container sizes:

• 1 litre container (Product Code: FC605120-1L)
• 5 litre container (Product Code: FC605120-5L)
• 20 litre container (Product Code: FC605120-20L)

Key Specifications and Properties

Physical Properties

Property	Specification
Specific gravity	1.02
Solids content	44 - 46%
VOC content	31 g / litre
Drying time at 20°C	2 - 4 hours
Maximum time between coats at 20°C	24 hours
Maximum overlay time at 20°C	8 hours
Minimum application temperature	10°C

Application Coverage

Nitoprime 330 provides coverage of 10 to 20 square metres per litre per coat after dilution with clean water. More practical guidance indicates 6 to 8 square metres per litre per coat, depending on surface absorbency and roughness. The coverage figures are for guidance only, as actual rates depend on the absorbency and surface roughness of the substrate.

Dilution Requirements

Nitoprime 330 is supplied as a concentrate and must be diluted before application. The standard dilution ratio is:

• 1 part Nitoprime 330 to 4 parts clean water by volume

This dilution ratio may be adjusted depending on surface porosity and specific application methods to achieve the desired coverage rates of 6 to 8 m² per litre.

Primary Applications and Uses

Recommended Flooring Systems

Nitoprime 330 is formulated specifically for use with the following cementitious flooring systems:

• Cemtop XD
• Cemtop Screed
• Cemtop HD30

Functional Benefits

The primer film performs multiple critical functions:

• Seals the substrate to prevent air release, which could otherwise cause pinholes in the floor topping
• "Wets out" the substrate to promote adhesion and prevent desiccation of the Cemtop coating
• Excellent adhesion to concrete and cementitious screeds
• Excellent water resistance after film formation
• Seals and prevents air release from subfloors

Application Instructions

Surface Preparation

Nitoprime 330 should be applied to sound concrete and cementitious screeds that are free from surface contamination and have been well prepared. The surface must be thoroughly cleaned and prepared before primer application.

Application Method

• Applied using a broom to work the primer into the floor surface
• Should NOT be applied by roller (not an approved application method)
• Should NOT be applied by spray (not an approved application method)
• The primer must be well brushed into the surface
• Ponding of the primer must be avoided as too thick a layer of cured primer may cause debonding

Recommended Application Schedule

Two coats of primer are recommended to ensure that the substrate is fully sealed and to minimise the likelihood of pinholes in the topping. For extremely porous floors, a third coat may be necessary.

First coat application:

• Applied after the existing concrete floor has been prepared and cleaned
• Diluted at ratio 1:4 (primer to clean water by volume)
• Applied and worked into the floor by broom

Second coat application:

• Should be diluted in the same ratio of 1:4
• Applied when the first coat is dry
• If the floor is still porous, a third coat at ratio 1:4 may be necessary

Curing between applications:

• The area should be well ventilated to speed the drying of the primer
• The application of Cemtop screed can proceed as soon as the final application of primer has dried

Special Circumstances

For dual layer Cemtop systems, the base layer should be primed with Nitoprime 330 as soon as the first layer has hardened.

Cleaning and Removal

Nitoprime 330 should be removed from tools, equipment and mixers with clean water immediately after use. Dried material can only be removed mechanically.

Application Limitations

Temperature Restrictions

Nitoprime 330 should not be applied when:

• The substrate surface temperature is below 10°C, or
• The temperature is likely to fall below 10°C within 48 hours of application

Unsuitable Substrates

Nitoprime 330 is not suitable for use on:

• Oil-contaminated concrete
• Existing epoxy toppings

Storage Requirements

• Store in the original unopened container
• Protect from frost and extreme heat

Advantages

• Economic and easy to use with no restrictive pot life
• Single-component system requiring no mixing
• Excellent adhesion properties to concrete and cementitious screeds
• Effective at sealing porous substrates while minimizing pinhole formation
• Water-resistant after film formation

Design Criteria

Successful application of cementitious self-smoothing screeds requires the substrate to be sealed to minimize air rising through the screed. For the majority of applications in both the industrial and commercial sectors, two coats of primer are recommended. If the floor is extremely porous, a third coat may be necessary.

References

• [1] Fosroc_Nitoproof_910_TDS.pdf
• [2] Fosroc_Cemtop_XD_TDS.pdf
• [3] Fosroc_Nitobond_SBR_TDS.pdf
• [4] Fosroc_Nitoprime_330_TDS.pdf
• [12] Fosroc_Cemtop_Screed_TDS.pdf