Bamboo Scrimber Anti-Mold: Technical Analysis from Material Properties to Process Control

What are the difficulties in preventing mold on bamboo scrimber?

Bamboo scrimber, also known as reconstituted bamboo, is a high-density material made by fiberizing and reconstituting bamboo under high temperature and pressure. Many factories assume that due to its high density and high glue content, mold cannot easily invade. However, in actual production, cases of mold on bamboo scrimber products are not uncommon. The reason is that while the manufacturing process changes the physical form of bamboo, it does not completely eliminate the nutrients inside—starch, sugars, proteins, etc., still remain. Once the environmental humidity is suitable, mold begins to grow on the surface or end grain.

Our tests found that under conditions of relative humidity above 85% and temperature 25-30°C, mold spots can appear on the surface of the same batch of bamboo scrimber boards within 72 hours. In contrast, samples treated with appropriate anti-mold measures remained mold-free for over 30 days under the same conditions. The key difference lies in whether the anti-mold agent truly penetrates the fiber interior and effectively inhibits the residual nutrients in the bamboo.

Core factors affecting the anti-mold effect of bamboo scrimber

To solve the mold problem of bamboo scrimber, simply spraying an anti-mold agent is not enough. It must be addressed from the material source and process stages.

1. Pretreatment of bamboo

Bamboo itself contains a large amount of sugars and starch, which are natural culture media for mold. If the bamboo strips are not fully desugared and degreased before reconstitution, the difficulty of subsequent anti-mold treatment increases exponentially. Common practices include high-temperature boiling or alkali soaking to reduce soluble sugars in bamboo to below 0.5%. We recommend that factories test the sugar content of bamboo strips upon receipt; batches exceeding 1% should be returned or treated separately.

2. Selection and application timing of anti-mold agents

Many factories spray anti-mold agents only after the reconstituted bamboo is formed, which has limited effect. Because the surface of bamboo scrimber is dense, the agent cannot easily penetrate. The correct approach is to mix the anti-mold agent with the glue during the bamboo fiber reconstitution stage. We recommend using iHeir-3/iHeir-4 packaging paper anti-mold and antibacterial agents. Their unique bonding, non-release mechanism permanently bonds to the bamboo fiber surface, forming an antibacterial layer. When mold contacts the product surface, the antibacterial layer punctures its cell membrane, quickly eliminating the mold. This treatment does not deplete due to killing bacteria, and its effectiveness lasts as long as the product’s lifespan.

Specific operating parameters: Add iHeir-3 at 1.5%-2% of the glue weight, mix evenly before use. Control the treatment temperature at 40-50°C, and maintain pH at 6.5-7.5. If the factory uses water-based glue, iHeir-4 is more suitable, with the same addition ratio.

3. Drying and packaging stages

After bamboo scrimber is formed, the moisture content must be controlled below 8% before packaging. Many factories only test the moisture content at the center of the board, ignoring differences at the ends and edges. We recommend multi-point testing to ensure uniform drying of the entire board. During packaging, use anti-mold treated packaging paper or non-woven fabric. Using ordinary packaging paper directly can become a medium for mold transmission once it gets damp during transportation. iHeir-3/iHeir-4 can be directly sprayed or soaked onto packaging paper, dried before use. The treated packaging paper effectively inhibits mold growth on the packaging surface.

Easily overlooked technical details

• Glue selection: Some urea-formaldehyde glues release formaldehyde during curing. Although formaldehyde can inhibit mold, it volatilizes and disappears, and is harmful to humans. It is recommended to use melamine-modified glue or MDI glue to avoid formaldehyde interference with the anti-mold effect.
• Storage environment: The relative humidity of the finished product warehouse should be controlled below 60%, and the temperature should not exceed 30°C. If the warehouse is humid, use desiccants or dehumidifiers.
• Transportation protection: During container transport, internal temperature differences can cause condensation. Place desiccants inside the packaging and spray anti-mold agent on the inner walls of the container.

Anti-mold treatment for bamboo scrimber is not a single-step process but a full-chain management from bamboo pretreatment, glue addition, drying control, to packaging and transportation. Only when every step is done correctly can the product be ensured to remain mold-free after leaving the factory.