How many years can the text on the label last without peeling off under oil stains and high temperatures?
1. What is ‘Marking Durability’?
In industrial engineering and the manufacturing of electrical and optical sensors, Marking Durability refers to the physical capability of text, barcodes, model numbers, and other identifying information affixed, sprayed, screen-printed, or directly etched onto a product’s surface (such as cable jackets, protective sleeves, casings, etc.) to maintain Legibility and Structural Integrity/Adhesion after enduring expected mechanical stresses (friction, abrasion), chemical solvent corrosion (industrial oils, cleaning agents, moisture), and thermal aging (cyclic high/low temperatures, sustained heat).
International and engineering tests commonly reference the following standards for evaluation:
- UL 969 (Marking and Labeling Systems): Evaluates the adhesive strength and legibility of labels in aging environments including oil immersion, high temperatures, and UV exposure.
- IEC 60068-2-70 / GB/T 2423.55: Tests for resistance to rubbing and abrasion of markings and labels.
- IEC 62368-1 / GB 4943.1: Specifies durability verification tests involving wiping with water and solvents like petroleum ether/n-hexane under specified pressure (typically 15 seconds).
2. How many years can a label last in an ‘Oily + High-Temperature’ environment?
The specific lifespan of label text under the combined effects of high temperature and oil contamination depends on the substrate material, adhesive type, ink/printing process, and the specific temperature, humidity, and chemical oil environment:
| Label Material & Process Type | Temperature Limit | Oil Resistance | Expected Lifespan in High-Temp Oily Environments |
|---|---|---|---|
| Standard PET / Vinyl Adhesive Labels (Wax/Resin Ribbon) | Continuous duty < 80°C | Poor (prone to swelling, peeling) | Weeks to 6 months. Oil quickly penetrates the adhesive, causing delamination, while high temperatures accelerate ink diffusion and degradation. |
| Chemically Resistant Polyester (PET) Labels (Resin Ribbon) | Continuous duty approx. -40°C ~ 120°C | Moderate to Good | 1 to 3 years. Stable in light lubricating oils or mists; prolonged immersion in strongly polar or synthetic oils may cause edge lifting. |
| Polyimide (Kapton) Industrial Labels (Solvent-Resistant High-Adhesion Resin Ribbon) | Continuous duty up to 150°C ~ 260°C (Short-term > 300°C) | Excellent (resistant to mineral oil, synthetic engine oil, and chemical solvents) | 3 to 5+ years. Designed for automotive engine bays, reflow soldering, and harsh industrial sites; text resists solvent dissolution. |
| 304/316 Stainless Steel Metal Plates (Laser Marking / Mechanical Stamping) | Can withstand > 500°C or higher | Very High (unaffected by any mineral oil or fuel corrosion) | 10 to 20+ years (Quasi-permanent). Physical or metallurgical changes to the text, unless subjected to severe mechanical abrasion, will ensure the markings last a lifetime. |
| Direct Laser Marking on Tube/Casing Surface | Dependent on substrate material’s temperature limit | Very High | Lifespan of the substrate structure. |
3. Physicochemical Mechanisms Leading to Marking Failure Under High-Temperature and Oily Conditions
- Chemical Dissolution and Swelling: Organic components like alkanes and aromatics in mineral oil, transformer oil, or synthetic lubricants diffuse into the label’s organic ink or adhesive layer (e.g., acrylic pressure-sensitive adhesive), causing plasticization, swelling, or even emulsification of the adhesive. This leads to label detachment or peeling of the ink layer.
- Thermal Oxidation and Molecular Chain Scission: Sustained high temperatures (> 100°C) accelerate the thermal oxidative degradation of the polymer substrate, causing embrittlement, yellowing, and cracking or peeling of the ink layer.
- Capillary Infiltration Effect: If oil contamination seeps along the edges of the label into the interface between the substrate and the adhesive, it rapidly destroys Van der Waals forces and chemical adhesion.
4. Engineering and Product Information
- Core Product Scope Explanation: OFSCN®'s (Beijing Dacheng Yongsheng Technology Co., Ltd.) core product series primarily encompasses Fiber Bragg Grating (FBG) sensors, distributed fiber optic sensing cables, special high-temperature resistant fiber optic patch cords, and demodulation systems. General-purpose adhesive labels, consumables, and printers are not part of OFSCN®'s (Beijing Dacheng Yongsheng Technology Co., Ltd.) core manufacturing scope.
- Engineering Recommendations for Harsh High-Temperature Conditions: For OFSCN® (Beijing Dacheng Yongsheng Technology Co., Ltd.) high-temperature fiber optic grating sensors encapsulated in seamless metal steel pipes (e.g., for temperature and force measurement scenarios operating at 120°C, 300°C, or even above 500°C), if the measurement point is in environments with high-temperature oil/gas media like oil wells, transformer insulating oil, or engine compartments, conventional paper or standard film labels are strictly prohibited. Engineering practice recommends using stainless steel laser-marked plates at the ends of armored sleeves or performing direct fiber laser marking on the stainless steel pipe surface to ensure the lifespan of the markings is consistent with the structural lifespan of the optical sensor.