Chromium Oxide Green (Cr₂O₃) serves as a functional filler and pigment in the paper industry, significantly improving optical properties, printability, and special functions of paper.

1. Applications in Paper

1.1 As Pigment Filler

Chromium oxide green provides unique green color for specialty papers:

• Security paper: Banknotes, bond papers, and other anti-counterfeiting papers
• Decorative paper: Packaging paper, gift wrap, wallpaper, etc.
• Filter paper: Industrial filter paper, coffee filters, etc.
• Label paper: Product labels, anti-counterfeiting labels, etc.

1.2 Functional Applications

Besides coloring, chromium oxide green also imparts special functions to paper:

• UV shielding: Cr₂O₃ can absorb UV light, protecting paper contents
• Antimicrobial properties: Has bacteriostatic effect under certain conditions
• Heat resistance: Improves high-temperature stability of paper

2. Technical Requirements

2.1 Particle Size Requirements

• Average particle size: 0.5-2μm
• Particle size distribution: Narrow distribution for uniform dispersion
• Specific surface area: 10-30 m²/g

2.2 Chemical Purity

• Cr₂O₃≥98%
• Water-soluble salts <0.5%
• pH: 6-8 (neutral, does not affect paper acidity)
• Heavy metal impurities meet food contact standards

3. Addition Process

3.1 Pulp Addition

Add chromium oxide green directly to paper pulp:

1. Pre-disperse chromium oxide green into slurry (10-20% concentration)
2. Add dispersant (such as sodium polyacrylate)
3. Add to pulp after beating, before wire section
4. Mix thoroughly to ensure uniform dispersion

3.2 Dosage Reference

• Light color paper: 0.1-0.5% (of dry pulp)
• Medium color paper: 0.5-2%
• Dark color paper: 2-5%

4. Product Specifications

• CRP-98: Cr₂O₃≥98%, Paper Grade
• CRP-99: Cr₂O₃≥99%, High-end specialty paper
• Ultra-fine: Particle size <1μm, suitable for thin paper

Contact us for paper application technical support and sample testing service.