Characteristics
Appearance: Yellow, transparent liquid
pH (10% aqueous solution): 2.0–3.0
Solubility: Miscible with water in any proportion.
Compatibility: Avoid contact with or simultaneous use of any reducing agents, ammonia solution, bleach, acids, or alkalis.

Advantages
1. Does not contain EU-banned chemicals such as manganese compounds, chlorine, bromine, iodine, formaldehyde, and APEOs.
2. It is a ready-to-use product that delivers localized fading effects on denim garments, resulting in a more natural look and a perfect vintage aesthetic.
3. Suitable for all types of fabrics, whether or not they contain elastane; delivers outstanding decolorization performance on both indigo and sulfur-dyed fabrics.
4. Simple application and safe operation; it can be used directly in place of potassium permanganate, with no need for additional steps such as calcination.
5. Does not contain heavy metals, halogens, formaldehyde, APEO, AOX, etc.
6. Its toxicity and hazardousness are far lower than those of potassium permanganate, with minimal environmental impact.

Reference Process

1. Apply the R-PP high-manganese substitute to selected areas of denim garments using a spray gun, or treat the finished garments with tools such as sponges, brushes, and gloves (under no circumstances should you touch the product directly with your hands or bare skin!). After treatment, allow the garments to stand at room temperature for at least 15 minutes to ensure a gentle, complete reaction; do not accelerate the reaction by drying or other methods. In addition, once the working solution has been sprayed, coated, wiped, or immersed, the fabric must be neutralized within 4 hours; otherwise, the fabric’s tensile strength may be compromised.
Recommended dosage: High-manganese substitute R-PP 50–80%; catalyst XH-2408 0–15%; the remainder is water.
If high whiteness is required, the catalyst dosage may be increased accordingly, but it should not exceed 20% at most.
2. Neutralization step: Treat with 2–3 g/L sodium metabisulfite at 40–50°C for 10 minutes;
3. Water passage.

Precautions

If slight yellowing occurs during the neutralization process as described above, the following neutralization procedure may be employed:
1. Treat with 2–3 g/L sodium percarbonate, 0.5 g/L caustic soda, and 1–2 g/L hydrogen peroxide at 45–50°C for 10 minutes, followed by rinsing with 2–3 g/L sodium metabisulfite at 45–50°C for 10 minutes.
2. When fabric colorfastness is severely compromised, it is recommended to add an appropriate dye-fixing agent during the rinsing step following the oxygen bleaching process described above.
· Considering fabric type and processing techniques, it is always recommended to conduct small-scale trials before full-scale production to verify in advance the likelihood of achieving the desired final results.
· Prolonged contact with or exposure to high temperatures can impair the product’s decolorizing performance or accelerate its reaction, while also potentially damaging the fabric’s strength and elasticity.
· After spraying the fabric with the working solution, allow it to air-dry at room temperature; never use high-temperature drying. Only proceed with neutralization once the fabric has dried to about 70–80% of its final moisture content. Special attention must be paid: do not leave the fabric untreated for more than four hours after applying the working solution before performing neutralization. We always recommend taking into account the type and intended application of the fabric and assessing in advance the most suitable conditions for each case.
· Given that the R-PP manganese substitute exhibits lower penetrative power in fabrics than potassium permanganate, it is recommended to use a brush to evenly apply the working solution after spraying.
· Certain plastic and metal containers (or accessories) are sensitive to the product. Whenever possible, use only high-density polyethylene or stainless steel containers, or at least verify their stability in advance.

Potassium permanganate is widely used for decolorization and bleaching in denim stone-washing processes, such as “spray monkey,” “hand-rub monkey,” and “stir-fry snowflake” techniques. However, as a strong oxidizing agent, potassium permanganate poses significant health risks to workers during handling and is also classified as a precursor chemical subject to strict control by public security authorities, making its purchase and storage cumbersome. Consequently, there is an increasingly urgent need to find alternatives to potassium permanganate. R-PP, a potassium permanganate substitute, is a milder decolorizing agent that contains no manganese, chlorine, bromine, iodine, or heavy-metal ions. It can be applied directly at room temperature—by spraying, rubbing, brushing, or stir-frying—without the need for dissolution or combination with phosphoric acid, making it more convenient to use than potassium permanganate while being more environmentally friendly and safer (though protective equipment, such as masks, gloves, and safety goggles, must still be worn during application). R-PP is therefore an ideal replacement for potassium permanganate in denim bleaching and decolorization.