If you import PVC decorative film into the EU, North America or Japan, the ink system used in printing matters as much as the film itself. The wrong ink can mean failed lab tests, customs rejection, or losing a retail contract because your supplier's product doesn't meet formaldehyde or VOC limits. Here's how water-based and solvent-based (oil-based) inks compare — and which one your market demands.

The Core Difference

Solvent-based (oil-based) inks use organic solvents — typically toluene, xylene, MEK, or ethyl acetate — as the carrier that dissolves the pigment and binder. As the ink dries, these solvents evaporate, leaving the colour on the film. Water-based inks replace most organic solvents with water, using a small percentage of co-solvents (usually glycol ethers) to control drying speed and film formation.

The critical difference isn't print quality — both systems can achieve excellent colour reproduction. It's what comes out of the film after printing: residual solvents and VOC emissions.

Regulatory Landscape by Market

Market	Key Regulation	Ink Requirement
European Union	REACH, E1 / CARB Phase 2 equivalent	Water-based strongly preferred; solvent inks must pass strict migration limits
USA	CARB Phase 2, TSCA Title VI	Formaldehyde ≤0.05ppm; water-based recommended
Japan	F★★★★ (JIS A 1460)	Strictest formaldehyde limits globally; water-based only
Middle East	SASO, ESMA (varies)	Solvent-based still accepted; shifting toward water-based
Southeast Asia	Green Label (Singapore), SIRIM (Malaysia)	Mixed; water-based gaining share for premium projects
Africa	Generally less stringent	Solvent-based dominates; budget-driven

Performance Comparison

It's a misconception that water-based inks are inferior. Modern water-based formulations from suppliers like Siegwerk and Flint Group match solvent systems in:

• Colour gamut: Equal — both achieve wide-gamut CMYK + spot colours
• Adhesion to PVC: Equal with corona-treated film surfaces
• Scratch resistance: Water-based often outperforms solvent inks in Taber abrasion tests
• UV / lightfastness: Comparable when using the same pigment types

Where solvent-based inks still hold an edge: drying speed on high-speed rotogravure presses and wet-on-wet trapping for complex multi-colour designs. However, the gap is narrowing every year as water-based chemistry improves.

Cost Differences

Water-based inks themselves are marginally more expensive per kilogram. But the total cost picture often favours water-based when you factor in:

• Solvent recovery / incineration: Solvent-based printing requires expensive RTO (regenerative thermal oxidiser) systems to capture VOCs. Water-based eliminates most of this.
• Insurance & safety: Solvent storage areas require explosion-proof electrics, fire suppression, and higher insurance premiums.
• Worker health: Fewer occupational exposure limits to manage with water-based inks.

GONGDA's Approach

We use water-based inks as standard across our entire decorative PVC film production. Every batch is tested for:

• Formaldehyde emission (EN 717-1, ≤0.05ppm)
• Heavy metal migration (EN 71-3, all elements below detection limit)
• Total VOC content (ISO 16000-6)

We can also run solvent-based inks on request for markets where compliance requirements are less stringent and budget is the primary driver — but we always disclose which ink system is used and provide the relevant test reports. See our certifications page for the full list.