Capacitive touch screen cover inks are divided into outdoor and indoor inks, so choose carefully.

     There's a clear distinction between outdoor inks and regular inks (usually referred to as indoor inks) used on touch screen cover lenses. Choosing the wrong ink material can negatively impact the product's appearance and user experience over time. In this article, the Shenzhen Hongjia Technology team explains how to choose the right ink.

     Outdoor inks are specially designed to withstand harsh outdoor conditions like sun and rain. Their weather resistance and durability far surpass those of regular inks, which are typically used indoors, such as in consumer electronics. Below is a comparison between the two:

A. Core Difference: Different Design Objectives

· Regular Ink (Indoor Ink):

· Objective: Primarily for indoor use, seeking excellent appearance (such as color saturation and gloss), processability, and cost control.

· Challenges: Mainly due to daily scratching and wiping with detergents.

Outdoor Inks (Highly Weather-Resistant Inks):

Challenges: UV-induced pigment decomposition and fading, water penetration causing blistering and peeling, and temperature fluctuations causing coating cracking.

B. Advantages of Outdoor Inks

Outdoor inks use UV-resistant resins and highly stable inorganic pigments (such as metal oxides) to withstand long-term UV exposure without fading or discoloration. Ordinary inks may noticeably fade after just a few months in outdoor sunlight.

Outdoor inks undergo rigorous accelerated aging tests (such as QUV and xenon lamp aging) to simulate prolonged exposure to wind, sun, and rain to ensure stable performance.

Outdoor inks offer stronger adhesion to the glass substrate, effectively preventing blistering and peeling caused by water vapor penetration.

Outdoor inks generally have greater elasticity and a thermal expansion coefficient more closely matched to the glass cover, allowing them to withstand drastic fluctuations from 70-80°C in the summer sun to sub-zero temperatures in winter without cracking.

Outdoor inks must also be resistant to acidic and alkaline substances in rainwater, as well as chemical pollutants in the air.

C. Application Scenarios

· Outdoor ink applications:

· Outdoor self-service terminals: Such as ATMs, ticket vending machines, and information kiosks.

· Industrial outdoor touchscreen devices: Such as outdoor control panels in factory workshops.

· Outdoor advertising machines/digital signage.

· In-vehicle display panels: Especially in the pre-installed market, these devices must withstand high temperatures and UV rays behind the windshield.

· Outdoor smart access control systems, express delivery lockers, etc.

· Conventional ink applications:

· Indoor smartphones and tablets.

· Home appliance control panels.

· Indoor POS terminals and self-service ordering machines.

· Indoor conference tablets and educational whiteboards, etc.

D. How to Select and Identify Ink

1. Identify the Use Environment: When designing a product, ink selection must be based on the intended use environment. If a product using conventional ink is placed outdoors, the ink will quickly degrade (fading or peeling), causing damage to the product's appearance and even affecting touch functionality.

2. Make clear requirements to suppliers: When inquiring and placing orders with touch screen cover suppliers, be sure to clearly indicate that the product is intended for "outdoor" use.

3. Cost trade-off: Avoid using standard inks on outdoor products simply to save costs. Otherwise, the subsequent repair costs and brand reputation damage will far outweigh the initial cost savings.

     Shenzhen Hongjia Technology has 12 years of experience in the R&D, production, and sales of 1.14-inch to 12.1-inch displays and accompanying touch screens. We have an experienced technical team and offer both indoor and outdoor inks for touch screen cover materials to meet specific customer requirements. We also accept custom services. Please email us for inquiries and we will provide free technical assistance and highly competitive quotes.