1. Screw cap and sealing performance
Cap material: PP or HDPE, transparent/color optional.
Sealing method:
Silicone/PE film inner pad (leakproof, suitable for liquids).
No gasket (special for dry samples).
Anti-opening design: Optional anti-theft ring (breaks when opened for the first time).

2. Physical properties
Temperature range:
PP material: -20℃~121℃ (autoclavable).
PET material: -20℃~70℃ (not autoclavable).
Transparency: Highly transparent (PET is better) or translucent frosted (PP).
Chemical compatibility: resistant to water, alcohol, weak acids and alkalis (strong solvents need to be tested).

3. Special design options
Tube bottom type:
Flat bottom (stable when placed upright) / conical bottom (convenient for centrifugation).
Tube body marking:
Laser scale (1ml interval) or label area (frosted surface).
Color coding: optional cap color (such as red/blue/green to distinguish sample types).

Since 2010, COLORPACK have been focusing on the printing of flexible packaging（BOPP/VMPET/PE ）, self-adhesive label, paper bags，packaging boxes, gift boxes etc to meet various needs for worldwide customers, which is an original professional manufacturer in CHINA, Customizing unique packaging for different brands of products，so that our customers can promote their brands and get better sales.
Our workshop is constructed in according with Industrial 4.0 intelligent standards, including 8,000m2 of 100,000 level dust-free purification workshop. Equipped with 4 sets of BOBST high-speed printing production lines, the printing speed reaches up to 400 m/min, with up to 10 printing colors.
There are 8 sets of high-definition intelligent digital QC inspection equipments to guarantee no defective products can be missed,together with our stringent quality assurance policy ensures ultimate customer satisfaction.With FDA, EU10-2011, ISO9001:2015 and FSSC22000 certified, we also implement the PDCA cycle improvement management system internally.
With the goal of "good quality, zero defects" to provide consumers with consistent high quality packaging products.