GRC Alkali-Resistant Sealing Primer

Product Category

GRC Alkali-Resistant Sealing Primer is the base course of a decorative wall system. Applied straight onto new cement, masonry or putty, it penetrates the substrate and forms a sealing film that blocks the alkali salts which otherwise bleed through and blotch the finish coat.

Sealing the base does two things at once: it stops the alkali attack that causes efflorescence, colour shift and peeling, and it equalises absorption so the main paint pulls evenly instead of flashing. The primer also grips the substrate firmly, so the following coats bond properly and the whole system lasts longer.

Key Characteristics:

1. Blocks alkali migration from cement and masonry substrates
2. Deep penetration into the base layer to seal and consolidate it
3. Equalises absorption so the main paint dries to an even colour
4. Strong adhesion between substrate and finish coats
5. Water resistant and breathable: the wall can still release moisture
6. Water-based, low odour and low VOC
7. Reduces main paint consumption by sealing a porous base

Best Applications:

• New Cement and Masonry With High Alkalinity: fresh mineral substrates that would otherwise attack the finish coat from underneath
• Putty and Skim-Coated Bases: the layer immediately before the main paint, where absorption has to be evened out
• Interior and Exterior Wall Systems: the same base course serving both, which keeps a project to one primer specification
• Porous or Unevenly Absorbent Substrates: walls that would drink the topcoat unevenly and dry to a patchy colour

Advantages:

• Stops Alkali Before It Reaches the Finish: the sealing film blocks the salts at the substrate, which is where efflorescence and colour shift actually start
• One Coat, Even Colour: equalising absorption is what stops the main paint flashing, so the finished wall reads as one flat colour
• Seals the Base, Saves the Topcoat: a sealed, non-porous base takes less main paint, which pays part of the primer back
• Adhesion Where Ordinary Primers Fail: formulated to grip smooth, non-porous surfaces such as tiles, glass and polished concrete, not only absorbent masonry
• Extends the Life of the Finish: a firm bond under the topcoat is what prevents the peeling and cracking that start at the base
• Low VOC, Indoors or Out: water-based and low in volatile compounds, so the same primer serves interior and exterior work

Product Parameters

• Colour: White
• Appearance: Liquid
• Coverage: about 8 ㎡ per kilogram
• Customization: Available

Where the Filler Comes From

Heavy calcium carbonate is the backbone of a water-based coating. It decides how the film builds, how hard it dries and how well it stands up to scrubbing — and it is the mineral that lets a formulator pull back on titanium dioxide, the most expensive ingredient in the can.

Ours comes from Nanzhao County in Nanyang, Henan — the district GRC's own mineral resources sit in, and one of China's four major heavy calcium carbonate bases alongside Haicheng in Liaoning, Qingyang in Anhui and Hezhou in Guangxi. It is the largest calcium carbonate cluster in central China, and its calcite runs to 98% CaCO3 at 92–95 whiteness: the grade that carries opacity and brightness into the film instead of simply adding bulk.

Because GRC owns the mine as well as the plant, that material reaches the mix directly rather than through a broker. Whiteness and particle grading stay steady from batch to batch — and so does the cost base when mineral prices move.

About Our Company

GRC has spent more than 16 years manufacturing building coatings, and today supplies contractors, design and renovation practices, and distributors. The range covers interior and exterior wall paints, floor coatings, waterproofing, primers and decorative finishes — enough breadth to carry a project from substrate preparation through to the final coat, on a family home or a commercial development alike.

Why Choose Us

Output of 60,000 tons a year means volume orders move without drama, and the same quality-control gates apply to every batch. The chemistry is water-based and low-emission, formulated to clear international standards including RoHS, REACH and France A+. Shipments reach more than 60 countries, and the reason customers come back is straightforward: a finish that holds up, at a price that works.

Technical Specification

• Package: 20KG / Barrel
• Main Raw Material: Acrylic
• Appearance: Liquid
• Application Method: Roller or brush
• Drying Method: Air Drying
• Certification: RoHS, ISO9001, REACH, France A+
• Origin: Nanyang, China

Standard Construction Process

1. Clean the base surface and let it cure fully
2. Apply one coat of sealing primer evenly with a roller or brush
3. Allow to dry completely before applying the main paint