Understanding the differences between flexo printing and gravure printing

Flexo Printing and Gravure Printing are currently the two most common printing technologies in the packaging and labeling industry. Each method has its own advantages and limitations in terms of technique, image quality, color durability, printing speed, operating costs, and environmental friendliness. Understanding the differences between these two methods helps businesses choose the right printing solution, optimize costs, and enhance quality.

Comparison of Flexo and Gravure Printing Technologies

Comparison of Flexographic Printing and Gravure Printing Techniques: Operating Principles

• Flexographic Printing:

• • • Mechanism: Liquid ink (water-based, solvent-based, or UV) from the ink pan is transferred through the anilox roller (ceramic-coated steel, engraved with small cells, 800 – 2000 LPI, ~2 – 3 million cells/inch²) to the raised printing plate (photopolymer/rubber). The raised plate presses the ink directly onto the substrate (paper, carton, plastic). A doctor blade removes excess ink from the anilox roller. Drying is done using hot air or UV after each color station.
    • Characteristics: Indirect ink transfer process (anilox → plate → substrate), easily integrates with post-press operations (die-cutting, embossing, hot stamping). Flexible in changing plates, but prone to ink spread (dot gain) due to soft printing plates.

• Gravure Printing:

• • Mechanism: Liquid ink (mainly solvent-based) fills recessed cells on the gravure cylinder (copper/chrome-plated steel, engraved ~6000 DPI, ~36 million cells/inch²). A doctor blade removes excess ink, and the cylinder presses the ink directly onto the substrate. Drying is done with hot air.
  • Characteristics: Direct ink transfer, high precision, excellent detail reproduction. However, cylinder manufacturing takes time and is not suitable for frequent design changes.
• Comparison: Flexo is flexible, easy to change plates, suitable for diverse orders. Gravure is more precise due to direct ink transfer but less flexible.

Comparison of Flexographic Printing and Gravure Printing Techniques: Image Quality

• Flexographic Printing:

• • • Characteristics: Sharp, consistent color, suitable for labels, logos, text, and simple packaging. Modern CTP technology (e.g., Kodak Flexcel NX, Esko HD Flexo) achieves print plate resolution ~4000 – 4800 DPI, but is limited by:
      • Anilox roller: Only 800 – 2000 LPI (~2 – 3 million cells/inch²), large cells (~15 – 30 microns), not precise enough for fine details (~4.2 microns at 6000 DPI).
      • Dot gain: Soft photopolymer plate deforms under pressure, causing ink spread, blurring fine details and complex gradients.
    • Limitations: Difficult to reproduce smooth gradients or ultra-fine details like Gravure.

• Gravure Printing:

• • Characteristics: Extremely sharp, high detail, smooth gradients due to engraved cylinders at ~6000 DPI (~36 million cells/inch², cell size ~4.2 – 10 microns). Direct ink transfer reduces dot gain and maintains accuracy.
  • Advantages: Ideal for complex designs, premium packaging, and high-quality imagery (magazines, catalogs).
• Comparison: Gravure excels in fine detail, smooth gradients, and sharpness thanks to high cell density and direct ink transfer. Flexo suits simpler designs but is limited by ink spread and the anilox roller.

Comparison between Flexographic Printing and Gravure Printing: On Color Durability

• Flexo Printing:

• • • UV/Solvent-based ink: Good color durability on plastic films (PE, PP), resistant to friction, mild light exposure, and some chemicals. Suitable for consumer packaging (bottles, plastic bags).
    • Water-based ink: Commonly used on paper/carton, lower color durability, more prone to fading under light or humidity if not coated with protective layers (laminate, varnish).
    • Application: Suitable for general packaging and short-term labels.

• Gravure Printing:

• • Solvent-based ink: Very high color durability, resistant to friction, UV light, chemicals, and harsh conditions (such as outdoor environments). Commonly used on plastic films (BOPP, PET) or metal.
  • Advantages: Long-lasting color retention, ideal for frozen food packaging and premium products.
• Comparison: Gravure offers superior color durability, especially on plastic films, due to strong solvent ink adhesion. Flexo performs well with UV/solvent inks, but water-based inks are less durable.

Comparison between Flexographic Printing and Gravure Printing: On Printing Speed

• Flexo Printing:

• • • High speed, approximately 100-400 m/min (depending on stack or CI Press machines). Suitable for labels, carton packaging, and plastic films.
    • May reduce speed when color registration is needed or when printing on difficult substrates (like thin plastics), but offers flexibility for medium/large orders.

• Gravure Printing:

• • Very high speed, approximately 200-400 m/min, stable at high speeds, especially on thin plastic films (BOPP, PET).
  • Requires fewer stops for adjustments due to precise engraved cylinders, ideal for continuous, large-scale production.
• Comparison: Gravure is faster and more stable at high speeds, making it ideal for large orders. Flexo is also fast but more flexible, suitable for diverse order types.

Comparison of Flexographic Printing and Gravure Printing Techniques: Cost Perspective

• Flexographic Printing:

• • • Initial Investment: Lower. Photopolymer printing plates are cheaper ($100 – $500/plate), and faster to produce (within hours to 1 day). Flexo printing machines (stack, in-line) are also more affordable ($100,000 – $500,000).
    • Operation: Cost-effective for medium to large orders (10,000 – 500,000 copies). Plates wear out faster (~1 – 2 million impressions), requiring frequent replacements.
    • Best Suited For: Flexible orders with frequent design changes (labels, consumer packaging).

• Gravure Printing:

• • Initial Investment: Higher. Copper cylinders are expensive ($1,000 – $5,000/cylinder) and take longer to produce (several days to a week). Gravure printing machines (CI Press) are more expensive ($500,000 – $2 million).
  • Operation: Cost-effective for large-volume orders (>1 million copies) due to durable cylinders (tens of millions of impressions). High costs for small batches due to difficulty in changing cylinders.
  • Best Suited For: Stable, large-volume orders (premium packaging, magazines).
• Comparison: Flexo is more cost-efficient for medium/large and flexible orders. Gravure is more economical for very large volumes but has high upfront investment.

Comparison of Flexographic Printing and Gravure Printing Techniques: Real-Life Applications

• Flexographic Printing:

• • • Packaging: Paper bags, cartons (food, beverage boxes), plastic films (PE, PP for food pouches).
    • Labels: Stickers for bottles, consumer products (dish soap, shampoo).
    • Others: Flyers, non-woven fabric packaging, folding cartons.
    • Advantages: Flexible, low-cost, suitable for varied production, widely used in general packaging.

• Gravure Printing:

• • Packaging: Premium plastic films (confectionery, frozen food), metallic films (cigarette packaging).
  • Premium Products: Magazines, catalogs, wallpaper, decorative packaging.
  • Advantages: High quality, ideal for premium products in large quantities.
• Comparison: Flexo is flexible and common for consumer packaging. Gravure is specialized for high-end packaging and high-quality products.

Comparison of Flexographic Printing and Gravure Printing Techniques: Environmental Friendliness

• Flexographic Printing:

• • • Inks: Water-based inks (low VOC, biodegradable), UV inks (solvent-free), solvent inks (ethanol/isopropyl, less toxic). Suitable for food packaging.
    • Solvents: Water or ethanol/isopropyl, low toxicity, easy to process. Simple solvent recovery system.
    • Plate Making: Photopolymer plates require fewer chemicals and are easier to recycle.
    • Energy Consumption (solvent inks): Lower. Simpler machines, drying at 50 – 80°C (ethanol/isopropyl dries quickly), energy-efficient solvent recovery.
    • Waste: Minimal. Water-based inks are easy to handle, and plates are recyclable.
    • Substrates: Paper, carton, recyclable plastic, supports eco-friendly packaging.
    • Advantages: More environmentally friendly, aligns with sustainable packaging trends.

• Gravure Printing:

• • Inks: Mainly solvent-based (ethyl acetate, toluene, high VOC), limited use of water-based inks. More toxic, less biodegradable.
  • Solvents: Ethyl acetate, toluene – highly toxic, requiring complex recovery systems.
  • Cylinder Production: Laser/chemical etching (acids, alkalis) generates hazardous waste.
  • Energy Consumption (solvent inks): Higher. Complex machines, drying at 80 – 120°C (ethyl acetate/toluene), energy-intensive solvent recovery.
  • Waste: More. Solvent inks and etching chemicals are hard to process.
  • Substrates: Plastic films (BOPP, PET), harder to recycle, less compatible with green packaging.
  • Limitations: Less eco-friendly due to toxic solvents, high energy use, and significant waste generation.
• Comparison: Flexo is more environmentally friendly due to water-based/UV inks, low-toxicity solvents, fewer chemicals in plate making, and recyclable materials. Gravure is less eco-friendly due to toxic inks/solvents, high energy use, and limited recyclability.

Based on the analysis above, both flexographic and gravure printing techniques have their distinct strengths, suited to different purposes and production scales. Flexo stands out for its flexibility, lower costs, ease of plate changes, and greater environmental friendliness—ideal for varied orders and sustainable packaging. Gravure, on the other hand, excels in sharpness, color durability, and high efficiency, making it the go-to choice for premium packaging in large quantities.

Depending on your actual needs, businesses can choose the most suitable printing technology to ensure both production efficiency and output quality.

If your business is seeking an optimal printing solution with high-quality raw materials, contact K-CHEM – a trusted supplier of printing chemicals in Vietnam.

K-CHEM VIETNAM CO., LTD

• Address: N6B Street, Lot F, Phu Chanh 1 Agricultural Cluster, Phu Chanh Ward, Tan Uyen City, Binh Duong Province, Vietnam
• Tel: +84 274 362 0218
• Email: info@k-chem.vn