Eco-Safe, High-Performance Coding: A Deep Dive into RoHS-Compliant Inkjet Inks for Small Character Printers Introduction: Why Ink Compliance Matters In today’s fast-evolving manufacturing landscape, safety and compliance are more than just regulatory obligations—they are competitive differentiators. For companies operating in highly regulated industries like food and beverage, electronics, or pharmaceuticals, the inks used in small character inkjet printers (CIJ) must meet strict environmental and safety standards. Non-compliance not only risks product recalls but can also damage brand credibility. This article highlights a recent third-party testing report of CHEEF’s inkjet printer inks, all of which passed stringent RoHS (Restriction of Hazardous Substances) evaluations. The results speak volumes about product safety, environmental responsibility, and manufacturing excellence. The Testing Overview: Trust Through Transparency The ink samples tested included models such as MB175, V411-D, W563-D, V4210-D, IR-270BK, IC-2BK106, 1067K, CN11, and others. These samples were submitted by CHEEF and evaluated by Centre Testing International (CTI) in Suzhou, China between July 29 and August 2, 2024. Testing Standard: RoHS Directive 2011/65/EU with amendment (EU) 2015/863 Conclusion: PASS RoHS compliance signifies the ink formulations are free from hazardous substances beyond the allowable thresholds, ensuring they are safe for the environment and human contact. What Was Tested? The comprehensive test covered the presence of heavy metals, brominated compounds, and plasticizers known to pose risks to human health and the environment: Heavy Metals Lead (Pb) Cadmium (Cd) Mercury (Hg) Hexavalent Chromium (Cr VI) Brominated Flame Retardants Polybrominated Biphenyls (PBBs) Polybrominated Diphenyl Ethers (PBDEs) Phthalates Dibutyl phthalate (DBP) Butyl

Introduction Shipping inkjet printer inks internationally requires more than just packaging and labeling. Due to their chemical compositions—often including volatile solvents—many inks are considered hazardous materials. The United Nations (UN) assigns specific classification codes to these materials to regulate their transport under international frameworks such as IATA (air), IMDG (sea), and ADR (land). This article breaks down the UN classification of inkjet inks, why it matters, and how you can ensure your shipments comply with international transport laws. — 1. What Is UN Classification? The UN classification system assigns a four-digit number (UN number) to hazardous substances, indicating their nature and transport risk. Each material is then grouped by hazard class (e.g., flammable liquid) and packing group (I, II, or III), which reflects its level of danger. UN Number: A unique identifier for hazardous goods (e.g., UN1210 for printing ink). Hazard Class: Categorizes the type of risk (e.g., Class 3 for flammable liquids). Packing Group: Determines packaging strictness (I = high danger, II = medium, III = low). — 2. Common UN Numbers for Inkjet Printer Inks Ink Type UN Number Hazard Class Packing Group Solvent-Based CIJ Ink UN1210 (Printing Ink) Class 3 (Flammable Liquid) II or III (depends on flash point) TIJ Water-Based Ink Not classified as hazardous N/A N/A DOD UV-Curable Ink UN1263 (Paint Related Material) Class 3 III Ink Solvent (e.g., MEK) UN1193 (Methyl Ethyl Ketone) Class 3 II Cleaning Solution Varies by chemical base Usually Class 3 II or III — 3. What Determines an Ink’s

Introduction Thermal Inkjet (TIJ) and Continuous Inkjet (CIJ) technologies serve distinct purposes in the industrial coding and marking industry. Each system uses a different type of ink optimized for its hardware and printing requirements. Understanding the differences between TIJ and CIJ inks is essential when selecting consumables for specific substrates, environments, and output speeds. — 1. Overview of CIJ and TIJ Technologies CIJ (Continuous Inkjet) Non-contact printing with pressurized ink streams Best for high-speed, high-volume production lines Inks recirculate through the system continuously TIJ (Thermal Inkjet) Contactless printing via heat-expelled droplets Compact, cartridge-based systems Ideal for small-scale, intermittent, or multi-line printing — 2. Ink Cartridge vs. Ink Reservoir System The biggest hardware difference between TIJ and CIJ lies in how ink is stored and delivered. TIJ Ink Cartridge Disposable cartridge with integrated printhead (typically HP45 type) Small capacity (40–45ml), easy to replace No internal filtration or ink recovery system CIJ Ink Reservoir Bulk ink tanks (typically 750–1000ml) Connected to a complex fluid circuit with filters, pumps, and valves Includes makeup fluids (solvents) and cleaning fluids for maintenance — 3. Ink Chemistry Differences Solvent Base CIJ inks: Ethanol, MEK (methyl ethyl ketone), or acetone-based TIJ inks: Water, ethanol, or glycol ether-based (less volatile) Viscosity CIJ ink: Very low viscosity (1–5 cps) TIJ ink: Higher viscosity (6–10 cps) to suit cartridge nozzles Drying Time CIJ: Fast-drying due to volatile solvents – suitable for high-speed lines TIJ: Slower drying unless ethanol-based – may require drying support — 4. Print Durability and Adhesion CIJ

Introduction Continuous Inkjet (CIJ) printers rely on two primary ink types: pigment-based and dye-based. Understanding the differences between these inks is crucial for selecting the right solution for your packaging, substrates, and production environment. In this article, we’ll explore their composition, advantages, limitations, and ideal use cases. — 1. What Are Dye-Based CIJ Inks? Dye-based inks consist of colorants that are fully dissolved in the solvent. These colorants are molecularly integrated, offering a uniform and stable solution. Characteristics include: High color brilliance and gloss Excellent solubility and consistency Shorter drying time compared to pigment inks Lower viscosity, ideal for high-speed printing Typical Applications Clear PET bottles Coated cartons Film and flexible packaging — 2. What Are Pigment-Based CIJ Inks? Pigment-based inks contain fine particles of solid colorants suspended in the ink carrier. These pigments do not dissolve but remain evenly dispersed with the help of stabilizers and dispersing agents. Features include: Higher opacity and better coverage on dark surfaces Superior UV resistance and fade resistance More durable under harsh industrial conditions Require agitation systems to prevent settling Typical Applications Dark-colored wires and cables Rubber or black plastic products Outdoor packaging or exposed parts — 3. Key Differences: Pigment vs. Dye Inks Feature Dye-Based Ink Pigment-Based Ink Color Strength Bright and vivid High contrast, especially on dark surfaces UV Resistance Lower High Dry Time Faster Moderate to slow Stability Stable without agitation Requires constant circulation Maintenance Low Higher (due to settling) Printhead Compatibility Most CIJ printers Requires special pumps and filters

Introduction Continuous Inkjet (CIJ) printers rely on precise fluid dynamics to deliver clean, sharp codes at high speeds. One of the most critical components in this process is the ink filter. Whether you are printing on bottles, cables, or cartons, the quality and condition of ink filters directly impact system reliability and print clarity. This article explains the types of CIJ filters, their functions, how often they should be changed, and how they affect print performance and maintenance costs. — 1. Why Ink Filtering Matters in CIJ Printing Removes particles that could clog nozzles or disrupt ink flow Prevents air bubbles that destabilize ink pressure Ensures consistent ink viscosity and conductivity Protects high-value components like pumps and solenoid valves Without effective filtering, print quality deteriorates quickly — leading to misprints, downtime, and costly repairs. — 2. Main Types of CIJ Filters Filter Type Function Replacement Interval Main Ink Filter Removes fine particles from ink before circulation Every 2,000–3,000 hours Make-up Filter Purifies solvent (make-up fluid) to ensure dilution quality Every 1,500–2,500 hours Return Filter Captures debris from ink returning from nozzle gutter Every 3,000 hours or with pump overhaul Pre-Filter (optional) Captures larger particles to extend main filter life Check monthly — 3. Filter Material and Micron Ratings Material: Most filters use PTFE, stainless steel mesh, or polypropylene to resist ink chemicals. Micron size: Common ratings include 5 μm or 10 μm. Smaller micron filters capture finer particles but may clog faster, requiring more frequent changes. Using an incorrect micron

Introduction Accurately calculating ink consumption per code is essential for cost control, production planning, and ink inventory management. Different inkjet technologies — CIJ, TIJ, DOD, and High-Resolution — have very different ways of delivering ink and therefore consume ink at different rates. This guide explains how to calculate ink usage per print for each type of system, using practical formulas and real-world examples to help you forecast cost per product and optimize efficiency. — 1. CIJ (Continuous Inkjet) Ink Consumption Method: CIJ printers eject a continuous stream of ink, and only part of it is used for printing. The rest is recycled or purged. Ink is consumed not only during printing but also during: Nozzle cleaning   Warm-up/startup purging   Approximate Formula: Typical Range: Standard alphanumeric code (2 lines, 15–20 characters): 0.015 – 0.035 ml Cost per 1000 prints: **$0.30–$0.70 USD** — 2. TIJ (Thermal Inkjet) Ink Consumption Method: TIJ cartridges specify the number of “ink shots” (drops) they contain. You can estimate per-code use based on the coverage and DPI (dots per inch). Formula: Example: 50×25mm barcode at 300 DPI = 0.3 – 0.6 ml per print — Example: 42ml cartridge yields ~600,000 characters (at 300 DPI, 2x4mm characters) 0.07 ml per code of 20 characters Typical Range: Simple text: 0.05 – 0.10 ml per code High-res or bold fonts: up to 0.15 ml — 3. DOD (Large Character Inkjet) Ink Consumption Method: DOD systems dispense large-volume drops for bold characters or logos. Drop size and character height heavily

Introduction In industrial inkjet printing, the match between ink formulation and substrate surface is crucial. Poor adhesion leads to smudging, fading, code rejection, or even regulatory non-compliance. Different printing technologies — CIJ, TIJ, DOD, and High-Resolution — require inks tailored for specific materials and surface energies. This article explores how ink adhesion works, why it’s different across substrates, and how to choose the right ink + printer combination for your application. — 1. What Affects Ink Adhesion? Key Factors: Surface energy of the substrate (how well liquids spread) Porosity — porous vs non-porous surfaces Ink chemistry — solvent vs water, dye vs pigment Drying time and curing conditions Surface Energy Examples: | Material | Surface Energy | Adhesion Difficulty | |———-|—————-|———————| | Polyethylene (PE) | Very low | Hard (requires MEK or surface treatment) | | Polypropylene (PP) | Low | Moderate–Hard | | Glass | High | Easy | | Paper/Cardboard | High | Very easy | | Rubber | Medium | Moderate | | Metal (aluminum, steel) | Medium–high | Easy with correct ink | — 2. Adhesion by Printer Type ### ✅ **CIJ (Continuous Inkjet)** – **Ink Type:** Fast-dry solvent (MEK/ethanol) – **Adhesion Strength:** Excellent on non-porous plastic, metal, glass – **Recommended For:** Bottles, cables, pouches, jars ### ✅ **TIJ (Thermal Inkjet)** – **Ink Type:** Water or ethanol-based – **Adhesion Strength:** Great on porous (paper, cardboard), limited on film/plastic – **Recommended For:** Cartons, boxes, labels ### ✅ **DOD (Large Character)** – **Ink Type:** Pigmented solvent or oil-based

Introduction In industrial inkjet printing, one of the most critical decisions is choosing between solvent-based and water-based inks. The ink’s base determines print quality, drying speed, substrate compatibility, odor, and safety. Each inkjet technology — CIJ, TIJ, DOD, and High-Resolution — has specific requirements and tolerances for solvent chemistry. This article provides a comprehensive comparison of solvent-based vs water-based inks and helps you determine which is best for your printing application and printer type. — 1. What Are Solvent-Based Inks? Solvent-based inks use volatile organic solvents such as MEK (methyl ethyl ketone), ethanol, or acetone as the carrier. These solvents evaporate rapidly after printing, leaving the colorant fixed to the surface. Advantages: Fast drying — ideal for high-speed lines Excellent adhesion on non-porous surfaces (plastic, metal, foil) High contrast and long-lasting marks Limitations: Strong odor and VOC emissions Flammable — requires Class 3 DG compliance Not suitable for food-contact zones without special certification — 2. What Are Water-Based Inks? Water-based inks use deionized water as the main solvent, with small amounts of additives like glycols or surfactants. These are commonly used in porous substrates like cardboard, kraft paper, and fiberboard. Advantages: Eco-friendly — low odor, low VOC Safe to use in food and pharma environments Lower shipping and storage hazard (non-DG) Limitations: Slow drying on non-porous surfaces Limited adhesion on plastics, film, or coated surfaces Can be sensitive to smudging or water exposure — 3. Solvent vs Water Ink by Printer Type Printer Type Solvent-Based Water-Based CIJ ✅ Primary choice

Introduction In the world of industrial inkjet printing, choosing between pigment-based and dye-based inks is not just a matter of color preference — it directly affects print quality, durability, nozzle maintenance, and printer compatibility. The ink formulation must suit both the printing technology (CIJ, DOD, or TIJ) and the substrate (material being printed). This article explores the differences between pigment and dye inks and how they are applied across Continuous Inkjet (CIJ), Drop-on-Demand (DOD), and Thermal Inkjet (TIJ) printing systems. — 1. What Are Dye-Based Inks? Dye inks are made by dissolving colorants in a liquid solvent such as MEK, ethanol, or water. The colorant molecules are fully solubilized and form a clear, homogeneous solution. Advantages: Simple formulation = less clogging High color vibrancy and clarity Fast drying on non-porous substrates Low maintenance requirements Limitations: Low UV and solvent resistance Prone to fading on outdoor or industrial surfaces Lower opacity — not visible on dark materials — 2. What Are Pigment-Based Inks? Pigment inks contain solid, finely ground color particles suspended in the liquid base. The particles remain dispersed (not dissolved), requiring special additives and agitation systems to stay stable. Advantages: Excellent UV, heat, and chemical resistance Strong contrast on dark surfaces (e.g., white ink on black cable) Durable markings on industrial parts Limitations: Risk of nozzle clogging if not circulated or flushed Heavier maintenance required Shorter open time (more sensitive to drying in the nozzle) — 3. CIJ: Pigment and Dye Ink Use ✔ Dye-Based CIJ Inks: Black, red,