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Capim Brazilian Clays

Capim Brazilian Clays Functional fillers and coating agents for optimum brightness and opacity

Capim clays from our high-quality kaolin deposit in Northern Brazil exhibit a ‘naturally engineered’ morphology which gives them an unparalleled combination of high brightness, narrow or ‘steep’ particle size and low abrasion. Capim clays make excellent functional fillers and coating agents where they confer optimum brightness and opacity along with excellent printability to the final paper.

Functional fillers

The combination of a coarse, steep particle size distribution (PSD) together with high brightness and low abrasion give coarse Capim filler grades a unique balance of properties. Their coarse, steep particle size boosts machine runnability through improved dewatering, better retention and good paper strength, while low abrasion prolongs wire life.

Capim grades also improve paper quality due to the combination of high natural brightness and decreased absorption.

In SC paper production, Capim kaolins are good alternatives to neutral conversion if high brightness is required without the compromise in surface properties and ink demand seen in neutral papermaking. Alternatively the scatter and brightness benefits can be traded for cost reduction through reduced pulp bleaching.

Capim fillers make ideal fillers for LWC base papers where high loadings can be achieved resulting in benefits to surface quality after coating.

Capim clay SEM


Capim clays exhibit a ‘naturally engineered’ morphology  combining high brightness, narrow particle size and low abrasion

Coating minerals

When used in the top coat, Capim grades deliver optical benefits, increased bulk and improved mottle performance against conventional glossing kaolins. These benefits in bulk and optics can enable gloss to be optimized through calendering.  Their use can help reduce expensive opacifiers such TiO2 in coating recipes.

The low level of ultrafine particles and low surface area of Capim clays improve coating strength enabling binder reduction compared to fine glossing kaolins or giving improved glueability in board and packaging applications.

The Capim coating range is ideal for:

  • LWC: Brightness, rheology, MSP runnability, gloss
  • MWC/CFS: Excellent scatter, rheology, gloss, opacity
  • Topcoat CWF: Brightness, reduced mottle, for gloss, silk matte and single coat
  • Coated B&P: Brightness, reduced mottle, glueability

Specialty papers

Used in silicone release papers for self-adhesive labels, Capim fine coating kaolins give good coverage and low porosity thus improving silicone hold-out.

Silicone is applied to the release base paper through a curing process using platinum catalyst. It is vital that the release base paper does not affect this process and mineral purity is extremely important to avoid "poisoning" this process. Capim clays guarantee high purity and chemistry ensuring compatibility with the platinum catalysts used in the siliconization process.  Their specialized processing minimizes any compounds that can adversely affect the silicone curing process that use platinum catalysts.



We offer a full range of bespoke formulation and technical and process support services to help you match the right mineral grade to your application requirement.

Please contact us. We will be only too happy to help

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Paper & Board