Cratusfilm help you Selection of right plastic Film if your the Process is cold  Printing Pressing

When selecting films for cold pressing printing, it’s essential to consider product requirements, process characteristics, and application scenarios. The following analysis and recommendations are provided from key dimensions:

1. Selecting the Film Type According to the Core Requirements of Cold Pressing Process

1. bond strength matching
   • Requirements: Cold pressing requires adhesives (e.g., EVA or PU) that cure at room temperature. The film must have excellent surface activity to ensure proper adhesive wetting and adhesion.
   • select ：
     • Polyethylene (PE) film: With low surface tension (approximately 31-34 dyn/cm), it requires corona treatment (to achieve over 38 dyn/cm) or coating with an adhesive layer (e.g., an AC agent). This makes it suitable for cold-press packaging applications with moderate to low adhesion requirements, such as food container film coating.
     • Polypropylene (PP) film: When untreated, it exhibits poor surface polarity. CPP (cast polypropylene) is the preferred choice due to its tightly packed molecular structure and corona-treated surface, which provides superior adhesion strength compared to BOPP. This makes it ideal for applications requiring high peel strength, such as book covers and gift boxes.
     • Polyethylene terephthalate (PET) film: high surface tension (after treatment, over 40 dyn/cm), good compatibility with solvent-based and water-based adhesives, excellent temperature resistance (short-term up to 120°C) and tensile strength, suitable for high-end cold-pressed products requiring secondary processing (such as foil stamping, die-cutting) like cigarette packs and cosmetic boxes.

2. bar pressure adaptability
   • Requirements: The cold pressing process eliminates high-temperature melting steps, and the film must exhibit sufficient flexibility and wrinkle resistance to prevent folding or cracking during lamination.
   • select ：
     • Film thickness selection: The film thickness should be matched with the substrate thickness. For example, 12-20μm film is commonly used for paper substrate (80-157g/m²), but too thick film will cause curling, and too thin film will cause pinhole. For metal or plastic substrate, 25-50μm film can be selected to enhance stiffness.
     • Flexibility is the key consideration: PVC film (polyvinyl chloride) offers exceptional flexibility, making it ideal for cold pressing irregular substrates like curved bottle labels. However, its environmental performance is subpar, requiring careful application when meeting export standards such as the EU REACH Regulation. As an alternative, PLA (polylactic acid) film is recommended for its biodegradability and flexibility comparable to PVC.

2. Selecting Thin Film Properties According to End Product Performance Requirements

1. Surface quality requirements
   • Glossy/Transparent: Choose BOPP glossy film (glossiness>80%) or PET transparent film with over 90% light transmittance, ideal for showcasing printed details like posters and brochures.
   • Matte/Fogged finish: Use BOPP matte film (with gloss <30%) or PE matte film. The micro-ribbed texture reduces glare and enhances tactile appeal (e.g., premium packaging or laptop covers). Note: The matte film must be bonded with a specialized matte adhesive to prevent uneven gloss after lamination.
   • Special tactile effect: Select a tactile film (e.g., polyurethane-coated PET film) with a velvet or leather-like surface. Ensure compatibility between the film coating and cold-press adhesive. We recommend conducting small-scale testing first.
2. Functional requirements
   • Waterproof and moisture-resistant: Choose PE film (polyethylene) or aluminum foil composite film (Al/PET). PE film offers excellent water resistance (water absorption rate <0.1%), making it ideal for food and pharmaceutical packaging. Aluminum foil composite film provides superior barrier properties (oxygen permeability <1 cc/m²·day), making it suitable for products requiring long-term storage, such as tea packaging.
   • Wear-resistant and scratch-resistant: Choose PET aluminum-coated film (surface hardness> 2H pencil hardness) or nylon (PA) film. The PA film has a puncture resistance of over 80N, making it ideal for products requiring frequent contact, such as handbags and instruction cover sheets.
   • Environmental/Recyclability: Prioritize single-material films (e.g., pure PP or pure PE) to avoid recycling challenges caused by material delamination in composite films (e.g., PET/PE). When export regulations mandate, use PCR (Post-Consumer Recycling) films such as PCR-PP films (with over 30% recycled content), which comply with U.S. EPR regulations.

3. Optimal Selection Based on Process Compatibility and Cost Control

1. adhesive compatibility
   • Cold pressing with water-based adhesive: Avoid using untreated PE films (which have poor wetting properties and are prone to delamination). Prioritize corona-treated CPP films or EVOH (ethylene-vinyl alcohol copolymer) films with polar groups to enhance adhesive anchoring performance.
   • Cold pressing with solvent-based adhesive: Compatible with most films, but solvent resistance must be considered. For example, PS (polystyrene) films swell easily with toluene and ethyl ester, so PET or PVC films should be used instead.
2. cost balance
   • Economy option: PE film (unit price approximately 1.2-2 yuan per square meter), ideal for mass production of low-value-added products such as courier packaging bags.
   • Mid-to-high-end value proposition: BOPP film (unit price 1.5-3 yuan/m²) delivers optimal performance-to-cost ratio, widely used in commercial printing applications.
   • High-end functionality: PET film (unit price 3-6 yuan/sq.m) or PVDC (polyvinylidene chloride) coated film (oxygen and moisture resistant), used for high-value-added products such as electronic device manuals and luxury packaging.

IV. Supplementary Selection Principles for Special Scenarios

• Outdoor weather resistance: The material must resist UV aging, preferably using PVDF (polyvinylidene fluoride) film or PET coated with SiO₂, with a weather resistance lifespan exceeding 5 years. It is suitable for outdoor advertising boards and cold-pressed fabric light boxes.
• For low-temperature applications: Avoid PVC films (which become brittle below 0°C). Opt for POE (polyolefin elastomer) films with low-temperature resistance up to-40°C, ideal for cold chain packaging such as frozen food labels.
• Post-processing for die-cutting/gold stamping: Select PET films with a thermal shrinkage rate below 1% to ensure dimensional stability during post-processing. During gold stamping, maintain a surface tension of over 38 dyn/cm to prevent foil detachment.

sum up ：

1. Define substrate type (paper/plastic/metal) → 2. Identify core requirements (adhesive strength/surface finish/functional properties) → 3. Select film material (PE/PP/PET etc.) → 4. Match thickness with surface treatment (corona treatment/coating) → 5. Test compatibility (adhesive + post-processing) → 6. Verify cost and environmental compliance.

Through the analysis, the cold pressing process film can be accurately selected to ensure the product quality is stable, the performance is up to standard and the cost is controllable.

Choose Cratusfilm , your film expert.