Cosmetics- Zhejiang Lisu Composite Materials Co., Ltd.

Cosmetics: Technical Guide to Materials for Core Components

Component Name	Recommended Materials	Key Technical Parameters (Typical Values)	Key Benefits and Solutions to Common Issues
High-strength plastic spring	Speciality High-Crystallinity PP	Flexural modulus: ≥1800 MPa	100% recyclable, rust-free: Replaces traditional stainless steel springs, addressing the issue of metal rusting and discolouration in lotions. Enables an all-plastic design, allowing for full-scale recycling without the need for disassembly.
		Fatigue life: >10,000 cycles
		Compressive set: <5%
Pump housing	High-Gloss, High-Flow PP	Gloss: ≥85%	Mirror-finish appearance, precision fit: Offers a high-end, glass-like lustre, eliminating the need for secondary coating. High flowability ensures moulding in multi-cavity moulds, with tight threaded connections and 100% leak-proof performance.
		Melt Flow Rate (MFR): 25–45 g/10 min
		Surface hardness: R-105+
Pump core / stem / piston	Slip-Modified PP	Coefficient of friction: 0.15–0.20	Smooth feel, responsive action: Internal lubrication modification significantly reduces friction during pressing, providing a silky, linear dispensing experience and preventing sticking or slow rebound.
		Tensile modulus: 1500 MPa
Soft nozzle / seal	Random Copolymer PP or TPE/TPU	Rockwell hardness: 40A–80A	Skin-friendly texture, perfect seal: Offers a soft and delicate tactile sensation. Excellent compression recovery ensures the pump head maintains a vacuum seal even after prolonged inactivity, preventing the oxidation of active ingredients.
		Compressive modulus: Low
Dip tube	Transparent Chemical-Grade PP	Tensile strength: 35 MPa	Corrosion-resistant, high transparency: Optimised for high-concentration essential oils and chemical ingredients, ensuring the straw does not yellow, become brittle or develop micro-cracks even after prolonged immersion.
		Environmental stress cracking resistance (ESCR): >1000 h

Application

Cosmetics