Question 1

What gloss level do matting agents achieve in can interior coatings?

Accepted Answer

Silica matting agents typically deliver 15–35 GU at 60° in can interior coatings at 1.5–3.0 wt% loading. The exact gloss depends on particle size distribution, film thickness, and resin chemistry. Finer grades (d50 3–4 µm) suit thin-film DWI spray applications, while coarser grades work better on sheet-coated can body stock.

Question 2

Are silica matting agents compatible with BPA-NI can coatings?

Accepted Answer

Yes, precipitated and gel-type silica matting agents are fully compatible with BPA-NI systems including modified polyester and acrylic-phenolic resins. Controlled silanol density ensures clean integration without disrupting crosslink formation. Loading should stay at 1.5–3.0 wt% to avoid viscosity buildup in these lower-crosslink-density matrices.

Question 3

How do matting agents perform under retort sterilization?

Accepted Answer

Properly specified matting silicas withstand 121 °C retort for 30–90 minutes with gloss shift of ±3 GU or less. Key requirements are low moisture content (≤5.0%), narrow particle size distribution with top-cut below 10 µm, and optional surface treatment to reduce water uptake at the filler-binder interface.

Question 4

What food-contact certifications should a can coating matting agent have?

Accepted Answer

At minimum, FDA 21 CFR 175.300 and EU Regulation 1935/2004 compliance are required. Overall migration must stay below 10 mg/dm², and specific migration data for any surface-treatment chemicals must be documented. For acidic beverages, extraction testing in 3% acetic acid at 121 °C is standard.

Question 5

Why are fumed silica matting agents not recommended for can interiors?

Accepted Answer

Fumed silica has excessively high oil absorption (≥300 ml/100 g) that starves the resin of binder, weakening barrier properties critical for food contact. It also tends to whiten under retort conditions. Fumed grades are better suited for exterior decorative coatings where retort and migration requirements do not apply.

Question 6

What particle size is optimal for beverage can interior matting?

Accepted Answer

A d50 of 3–5 µm with top-cut below 10 µm is optimal. In two-piece DWI beverage cans where interior spray coats are only 5–7 µm thick, finer grades (d50 2.5–4 µm) prevent particle protrusion through the film while still achieving target gloss reduction.

پارامتر	نوع ژل (داخلی قوطی)	رسوبی (بسته‌بندی فلزی عمومی)	فیومد (فقط خارجی)
اندازه ذرات d50	3–5 µm	4–7 µm	توصیه نمی‌شود
جذب روغن	200–260 ml/100 g	220–280 ml/100 g	≥300 ml/100 g
محتوای رطوبت	≤5.0%	≤6.0%	≤1.5%
بارگذاری توصیه‌شده	1.5–3.0 wt%	2.0–4.0 wt%	—
رتورت 121 °C / 30 دقیقه	قبول	قبول	رد (سفیدشدگی)
FDA 21 CFR 175.300	بله	بله	بسته به مورد

عامل مات‌کننده برای پوشش‌های قوطی و بسته‌بندی فلزی.

سازگاری سیستم BPA-NI

عملکرد رتورت و استریلیزاسیون

کنترل براقیت و پنجره اعمال

چشم‌انداز مقرراتی تماس مواد غذایی

مقایسه مشخصات: گریدهای پوشش قوطی

ترکیب با SEMITI TiO2

سوالات متداول

Talk to a chemist about عامل مات‌کننده برای پوشش‌های قوطی و بسته‌بندی فلزی.