{"id":"wpc-tech100-article-003-en","slug":"masterbatch-dilution-in-composite-recipes","locale":"en","url":"https://woodplasticcomposite.net/guides/masterbatch-dilution-in-composite-recipes/","title":"Masterbatch dilution in composite recipes","answer":"A masterbatch dosage is not the same as the active ingredient dosage. Confusing the two can change colour, stabilisation and the polymer balance of a wood-plastic composite.","author":"NFC & WPC Knowledge Reference","faqIds":["wpc-tech100-faq-003-en"],"tagIds":[],"noindex":false,"related":["wpc-tech100-article-004-en"],"version":1,"modified":"2026-10-15","reviewer":"","sections":[{"id":"technical-context","text":"An illustrative 2% addition of a masterbatch containing 30% pigment contributes 0.6% pigment and 1.4% carrier to the final mixture, when all values share the same mass basis. The carrier is part of the formulation rather than an invisible ingredient.","heading":"Technical context","references":[],"url":"https://woodplasticcomposite.net/guides/masterbatch-dilution-in-composite-recipes/#technical-context"},{"id":"verification-plan","text":"Record the active concentration, carrier identity and recommended processing range. When replacing a masterbatch, compare the actual active input and carrier contribution rather than matching the old dosing percentage automatically.","heading":"What to measure and document","references":[],"url":"https://woodplasticcomposite.net/guides/masterbatch-dilution-in-composite-recipes/#verification-plan"},{"id":"practical-decision","text":"Approve the substitution through a documented trial. Inspect colour, surface quality and relevant mechanical properties after processing. A numerically equivalent pigment dose does not establish compatibility between a new carrier and the original WPC matrix.","heading":"Implications for development and specification","references":[],"url":"https://woodplasticcomposite.net/guides/masterbatch-dilution-in-composite-recipes/#practical-decision"},{"id":"reading-scope","text":"Official guidance on controlling measurement processes and supporting uncertainty statements. Use the linked work as related reading. The practical checks above are editorial recommendations, not reported test results or a substitute for product qualification.","heading":"Related reading and evidence limits","references":[1],"url":"https://woodplasticcomposite.net/guides/masterbatch-dilution-in-composite-recipes/#reading-scope"}],"seoTitle":"Masterbatch dilution in composite recipes | WPC Reference","topicIds":[],"published":"2026-10-15","tableText":"Review step | Evidence to retain\nMaterial and geometry | Exact specimen or product identity\nVerification | Method, conditions and individual observations\nDecision | Approved scope and documented limitations","takeaways":"An illustrative 2% addition of a masterbatch containing 30% pigment contributes 0.6% pigment and 1.4% carrier to the final mixture, when all values share the same mass basis.\nRecord the active concentration, carrier identity and recommended processing range.\nApprove the substitution through a documented trial.","aiAssisted":true,"categoryId":"wpc-tech100-category-0","reviewedAt":"","change_note":"New focused technical draft; not a product certification or production recipe.","description":"A masterbatch dosage is not the same as the active ingredient dosage.","heroImageId":"","referenceIds":["wpc-tech100-ref-measurement"],"review_status":"AI-assisted English editorial draft. Human technical review has not been recorded.","table_caption":"Evidence checklist for masterbatch dilution in composite recipes","seoDescription":"A masterbatch dosage is not the same as the active ingredient dosage.","translationGroup":"wpc-tech100-003-2026","references":[{"url":"https://www.itl.nist.gov/div898/handbook/mpc/section2/mpc2.htm","type":"web","title":"NIST: statistical control of measurement processes","noindex":false,"accessed":"2026-10-14","seoTitle":"NIST: statistical control of measurement processes","publisher":"NIST","description":"Related reading; scope and limitations are identified in each article.","seoDescription":"Related reading; scope and limitations are identified in each article."}],"faqs":[{"question":"What evidence is needed for masterbatch dilution in composite recipes?","answer":"Record the active concentration, carrier identity and recommended processing range. When replacing a masterbatch, compare the actual active input and carrier contribution rather than matching the old dosing percentage automatically."}]}