1.Pre-Procurement: Hidden Traps in Material Quality and Qualifications

1. Open with a real-case scenario of a food factory suffering product spoilage due to purchasing inferior composite bags to highlight the importance of pitfall avoidance.
   
   
2. Material substitution trap
   • Distinguish cost differences between PET and nylon materials, and teach readers to identify them via a "bending test" (nylon can be repeatedly bent without whitening, while PET is prone to brittleness and cracking).
   • Supplement testing methods for barrier properties of aluminized vs. aluminum foil bags (aluminum foil bags offer complete light shielding, whereas aluminized bags have light-transmitting gaps).
3. Compliance qualification trap
   • Specify requirements such as the GB 4806.7 standard for food-grade composite bags and FDA certification for export products.
   • Attach 3 key steps for qualification verification to avoid purchasing dry-laminated bags containing benzene-based solvents.

2.Mid-Procurement: Numerical Scams in Sampling and Costing

1. Sample testing pain point & solution
   • Target the pain point of small businesses neglecting sample testing, and propose the "3 mandatory tests for sampling":
     • Using a colorimeter to measure ΔE value (≤2 is qualified)
     • Using a tensile machine to test heat-seal strength (≥3N/15mm)
     • Conducting temperature/acid resistance tests simulating warehouse storage conditions
   • Include a reference table of testing standards for different types of composite bags.
2. Cost trap
   • Expose low-price quotation tricks (e.g., reducing printing color count or material thickness).
   • Provide a cost composition formula (60% materials + 20% printing + 20% plate fees).
   • Offer cost-saving solutions for material selection based on product characteristics (e.g., KPET/CPP for biscuits, PET/AL/PE for sauces).

3.Post-Procurement: Safeguards in Inspection and After-Sales Service

1. 3-step inspection process
   • Conduct leak tests on sampled bags (no air bubbles when filled with water and squeezed)
   • Check printing precision (no double images or blurring, minimum font size ≥6pt)
   • Verify environmental compliance (certification requirements for biodegradable PLA materials under 2025 new regulations)
   • Remind readers to retain samples as evidence for rights protection.
2. After-sales risk avoidance guidelines
   • Clarify after-sales differences between original factories and intermediaries.
   • List contract clauses such as "free reprinting for quality issues" and "replacement for size errors".
   • Attach 3 screening criteria for reputable suppliers (100,000-class clean workshops, independent R&D teams, and 500+ service cases).