Plastic Mountage

Plastic Mountage — known in the sericulture industry as chandrika or netrika — is a corrugated HDPE mesh frame used in silkworm rearing houses for cocoon mounting. Ripe silkworms (fifth instar) are transferred onto the expanded pleated mountage, where they attach and spin their cocoons in the troughs between the corrugated ridges. Once spinning is complete, cocoons are hand-harvested by sliding fingers along the ridges.

Manufactured from 100% virgin HDPE, plastic mountage replaces traditional bamboo and straw chandrika frames with a hygienic, reusable alternative that does not harbour mould, bacteria or parasites between rearing cycles. The fine diamond-mesh construction provides grip for silkworm attachment while allowing air circulation through the rearing house — critical for maintaining the humidity and temperature conditions that produce high-quality cocoons.

Each mountage panel is approximately 0.9 m wide with 11 accordion folds, creating deep vertical pleats that maximise cocoon-holding capacity per unit floor area. The panels are fully expanded and laid flat on the rearing house floor (or on raised racks in some setups) — not bundled or tied during use. After each rearing cycle, mountages are cleaned, dried and stored for the next crop.

The sericulture workflow using plastic mountage follows four stages: (1) Mounting — ripe silkworms are hand-picked from mulberry feeding trays and gently placed onto expanded mountage; (2) Spinning — worms attach to the mesh and spin cocoons over 3–4 days; (3) Harvesting — mature cocoons are collected by hand along the corrugated ridges; (4) Cleaning — mountages are washed and sun-dried for reuse. A single mountage panel can be reused for many rearing cycles.

Used across sericulture belts in Karnataka, Andhra Pradesh, Tamil Nadu, West Bengal and Maharashtra — by individual rearers, sericulture cooperatives and government silk farms. Plastic mountage improves cocoon quality (uniform shape, cleaner surface), reduces disease incidence compared to organic frames, and significantly cuts the labour and material cost of preparing fresh bamboo chandrika for every crop.