How To Choose UV Ink For Different Paper Types?

1. Paper Types & Compatible UV Ink Properties
2. General Key Metrics for Selecting UV Inks
3. Industry Scenario Adaptation Examples
4. What are the effects of different paper types on the selection of UV inks?
5. How to test and verify the performance of UV inks on different paper types?

 

 

 

1.Paper Types & Compatible UV Ink Properties

 

Coated paper (glossy/matt)

Features: smooth surface, low ink absorption, high gloss.
Suitable inks:
High gloss UV ink: enhances the mirror effect of printed products.
Low viscosity ink: avoids leveling problems caused by high surface tension of paper.
Quick drying ink: ensures fast curing during high-speed printing.
Note: The compatibility of ink and paper coating needs to be tested to avoid shrinkage or insufficient adhesion.

 

Cardboard (thick paper, such as packaging cardboard)

Features: high thickness, tight fibers, medium ink absorption.
Suitable inks:

High solid content ink: provides full color and hiding power.
Flexible formula: adapts to the need for crack resistance when cardboard is folded.
Abrasion-resistant ink: suitable for high-frequency friction scenarios such as handbags.

Corrugated paper (rough surface)
Features: porous, rough surface, easy to absorb ink.

 

Suitable inks:
Inks with high penetration: ensure that the ink penetrates and adheres to the deep layers of the fiber.
Low viscosity formula: avoid excessive absorption due to large paper pores.
High hiding power ink: cover the uneven color of the corrugated paper itself.

Recycled paper (including recycled fibers)
Characteristics: porous surface, possible impurities, unstable pH value.

 

Suitable inks:
Neutral pH ink: avoid reaction with alkaline substances in paper.
Migration-resistant ink: prevent ink components from migrating into the paper.
Environmentally certified ink: in line with the sustainable positioning of recycled paper.
Uncoated paper (such as newsprint, writing paper)
Characteristics: rough surface, strong ink absorption, low gloss.

 

Suitable inks:
Quick drying ink: reduce drying delays caused by paper absorption.
Matte or flat ink: match the low gloss characteristics of the paper itself.
Low-cost ink: balance printing quality and economy.

 

 

2.General key indicators for selecting UV inks

Adhesion
Verify the bonding strength of ink to paper through the Baige test (ASTM D3359).
For non-absorbent paper (such as metal foil), ink containing coupling agent should be selected.
Drying speed

 

Adjust the power and wavelength of UV lamp (usually 365nm or 395nm) according to the speed of the printing press.
Porous paper requires higher energy curing to avoid adhesion caused by the surface not being dry.
Rheological properties
Low viscosity inks are suitable for high-speed printing and fine dots; high viscosity inks are suitable for solid color blocks.
Weather resistance
For outdoor printing, choose yellowing-resistant and UV-resistant inks (such as adding hindered amine light stabilizers).
Environmental compliance
Food packaging must be FDA certified, and children's products must comply with EN71-3 heavy metal limits.

 

Industry scenario adaptation examples
Food packaging: Choose low-migration, odorless inks and pass FDA certification.
Luxury packaging: High gloss, tactile inks (such as frosted, wrinkle effects).
Children's books: Inks that are resistant to friction and finger oil stains and meet safety standards.
Express labels: Heat-resistant and scratch-resistant inks that adapt to logistics environments.

 

Precautions
Pretreatment requirements: Some papers (such as PP coated paper) need to be corona treated first.
Storage conditions: The ink needs to be kept away from light and at low temperatures to avoid gelling or component separation.
Equipment compatibility: Make sure that the UV curing equipment matches the ink (such as mercury lamps vs LED lamps).

 

 

3.Industry Scenario Adaptation Examples

 

Food Packaging

Key Requirements: Low Migration, Odorless, Heat-Resistant, FDA-Certified

Compatible Inks:

Low Migration UV Screen Printing Inks: Special resin systems ensure migration < 0.01 mg/dm² via FDA 21 CFR 175.300 compliance.

LED-UV Screen Inks: Low-temperature curing preserves paper coatings for dairy and baked goods packaging.

Applications: Chocolate gift boxes, water bottle labels, microwave-safe containers.

 

Luxury Packaging

Key Requirements: High Gloss, Tactile Effects, Metallic Finish

Compatible Inks:

High-Gloss UV Screen Inks: Achieve >100 GU gloss for premium mirror effects.

Special Effect UV Screen Inks:

Frosted UV Screen Inks: Micro-particle formulas create textured surfaces.

Wrinkle UV Screen Inks: Natural crackle patterns enhance luxury appeal.

Applications: High-end cosmetics cases, wine bottles, jewelry displays.

 

Children's Books

Key Requirements: Friction-Resistant, Finger-Oil Resistant, Safety-Compliant

Compatible Inks:

Scratch-Resistant UV Screen Inks: Pass Taber Abrasion Test (5,000 cycles).

EN71-3 Compliant UV Screen Inks: Heavy metals < 90 ppm, saliva-resistant per ISO 6270-2.

Applications: Early-learning books, pop-up storybooks, coloring pads.

 

Express Delivery Labels

 

Key Requirements: Temperature-Resistant, Scratch-Resistant, UV-Resistant

Compatible Inks:

 

High-Durability UV Screen Inks: Withstand -40°C to 80°C for Cold Chain Logistics.

UV-Curable Adhesive Inks: Direct printing on PE/PVC films with >5N/cm adhesion.

Applications: Parcel labels, hazard warnings, warehouse tags.

 

Technical Parameter Comparison Table

 

Industry	Ink Type	Critical Metrics	Certifications
Food Packaging	Low Migration UV Screen Inks	Migration < 0.01 mg/dm², odor ≤2	FDA 21 CFR 175.300
Luxury Packaging	High-Gloss Special Effect Inks	Gloss >100 GU, fold resistance ≥180°	ISO 12647-2 (Color Standard)
Children's Books	Safety-Compliant UV Screen Inks	Heavy metals <90 ppm, friction coeff <0.3	EN71-3, ASTM F963
Express Labels	High-Durability UV Screen Inks	Lightfastness 8 ,alcohol resistance ≥100 wipes	ISO 2819 (Logis

 

 

4.What are the effects of different paper types on the selection of UV inks?

 

Surface roughness
Rough paper (such as corrugated paper, recycled paper):
You need to choose inks with strong permeability (such as low viscosity formulas) to ensure that the ink penetrates deep into the fiber to avoid "whitening".

 

Adhesion requirements: pass the Baige test (ASTM D3359) ≥3B level.
Smooth paper (such as coated paper, metal foil):
Adhesion-enhancing inks (including coupling agents) or primer pretreatment are required to prevent shrinkage or shedding.

Ink absorbency
Highly ink-absorbent paper (newsprint, uncoated paper):
Choose fast-drying inks (such as LED-UV inks) with a curing time of < 0.5 seconds to avoid smudging caused by delayed drying.
Low ink-absorbent paper (coated paper, plastic film):
Low viscosity inks are required to ensure leveling, and rheological control (such as thixotropy) is used to prevent dot enlargement.

Thickness and stiffness
Thick cardboard, corrugated paper:
The ink should be flexible (elongation at break > 20%), adaptable to folding and cracking resistance;
High solid content ink (solid content ≥ 50%) provides full covering power.

 

Influence of paper chemical properties
Recycled paper (alkaline environment):
Choose neutral pH ink (pH 6.5-7.5) to avoid reaction with alkaline substances in paper to cause discoloration or decreased adhesion.

Surface coating
Metal foil, pearlescent paper:
Special UV metal ink or conductive ink is required, and corona treatment is used to increase the surface tension to more than 40mN/m.
Thermal paper:
Choose low-temperature curing ink (LED-UV) to avoid high temperature (>80℃) damaging the thermal coating.

Key points for ink performance matching

Curing characteristics
High-speed printing (such as corrugated boxes):
High-energy curing ink (365nm mercury lamp) is required to ensure instant drying.
Special papers (such as films):
Choose low migration inks (migration amount < 0.01 mg/dm²) that meet food packaging safety standards.

Functional requirements
Outdoor advertising (sun and rain):
Choose weather-resistant inks (add light stabilizers) that pass the QUV accelerated aging test (500 hours ΔE<2).
Children's books (frequent touch):
Choose friction-resistant inks (Taber abrasion test ≥5000 turns) with heavy metal content < 90ppm.

 

5.How to test and verify the performance of UV inks on different paper types?

 

Core laboratory tests
Adhesion: The ink-paper bonding strength is evaluated by the 100-grid test (ASTM D3359) (non-absorbent paper must be ≥4B), and the moisture and heat resistance is strengthened by the boiling test.
Drying speed: The curing energy (800-1500 mJ/cm²) is measured using a UV energy meter to ensure that the curing time is < 0.5 seconds under high-speed printing.

 

Weather resistance: The ink stability is verified by the QUV accelerated aging test (500 hours ΔE<2) and the temperature and humidity cycle test (-40℃ to 85℃).
Physical properties: The gloss meter and Taber abrasion tester are used to test the gloss (coated paper > 80 GU, matte paper < 30 GU) and abrasion resistance (children's books < 0.1g weight loss).

 

Field printing verification

Parameter optimization: adjust the UV lamp power (mercury lamp 365nm/LED lamp 395nm) and the number of lines of the anilox roller (corrugated paper 120-150 lpi, coated paper 200-300 lpi) to ensure printability.
Effect observation: check the dot reproduction (20-80% clear gradation) and anti-smearing (no sticking after stacking for 24 hours).
Special paper adaptation: verify the ink coverage uniformity of metal foil/pearl paper, and ensure that thermal paper uses LED-UV ink (curing temperature < 80℃).

 

Targeted paper testing
Porous paper (corrugated paper, recycled paper):
Focus on testing permeability (avoiding print-through) and hiding power (OP value ≥95%).
Non-absorbent paper (coated paper, film):
Focus on testing leveling (scraper fineness meter to detect uniformity) and adhesion (peel strength ≥5N/cm).

 

Through the above systematic tests, the compatibility of UV ink and paper can be fully verified to ensure stable printing quality. It is recommended to conduct periodic re-inspections of ink and paper every quarter to deal with the risks brought by material or process changes.