iPhone 4 Screen Blotching Resolves Itself as Bonding Agent Dries? [Updated] - MacRumors
Skip to Content

iPhone 4 Screen Blotching Resolves Itself as Bonding Agent Dries? [Updated]

112948 iphone 4 discoloration 3

Yesterday, we reported that a number of iPhone 4 users have noticed yellowish or brownish splotches on their device's screens, obviously causing a fair amount of concern for some of those users.

According to a forum post at AppleInsider, however, the issue should resolve itself over the next several days, as it is claimed to be caused by a bonding agent in the screen that has not yet fully dried following the manufacturing process.

Apple is using a bonding agent called Organofunctional Silane Z-6011 to bond the layers of glass. Apparently, Apple (or more likely Foxconn) is shipping these products so quickly that the evaporation process is not complete. However, after one or two days of use, especially with the screen on, will complete the evaporation process and the yellow "blotches" will disappear.

How do I know? I was involved in pitching Z-6011 to Apple.

The veracity of the poster's claim has not been verified, but it does offer some hope to those affected by the issue. Adding to those hopes are reports from users that their blotches are in fact fading with time and usage, indicating that affected users should probably take a wait-and-see attitude for a few days rather than rushing out to their local Apple Stores in hopes of exchanging for new units.

I had major yellow spots on the bottom corners of the iPhone 4 this morning when I received it (as shown in the other thread) and as of right now they have COMPLETELY faded away. I have no idea what caused this but it happened. So keep an eye on it over the next day or so if you have the issue. . . It just seemed like the more I used the phone today the more it faded. It's really odd but I'll take it.

Update: Gizmodo is reporting that Apple support staff are issuing conflicting recommendation to users with this issue, with at least one user reportedly receiving confirmatory word from Apple that the issue is "residue from manufacturing" that should clear on its own within a few days while others have been told to bring in their phones for replacement.

Related Forum: iPhone

Popular Stories

apple wallet drivers license feature iPhone 15 pro

Apple Says iPhone Driver's Licenses Will Expand to These 6 U.S. States

Thursday July 9, 2026 7:29 am PDT by
In select U.S. states, residents can add their driver's license or state ID to the Apple Wallet app on the iPhone and Apple Watch, and then use it to display proof of identity or age at select airports and businesses, and in select apps. To set up the feature, open the Wallet app on the iPhone and tap on the plus sign in the top-right corner. Next, tap on Driver's License and ID Cards,...
apple silicon 1 feature

Apple Silicon is Taking an Unexpected Turn

Friday July 10, 2026 7:24 am PDT by
Ever since the Mac switched from Intel processors to Apple silicon starting in 2020, each generation of M-series chips has included higher-end Pro and Max variants. If a recent report proves to be accurate, though, that streak will be coming to an end. According to Bloomberg's Mark Gurman, Apple will be releasing a regular M6 chip, but it has no plans to offer higher-end M6 Pro and M6 Max...
iphone 16 teal

'Siri AI' Lawsuit Update: Apple to Pay Owners of These iPhone Models

Thursday July 9, 2026 7:08 am PDT by
In May, Apple agreed to pay $250 million to settle a U.S. class action lawsuit over Siri AI's delayed launch, and eligible iPhone users could receive up to a $95 payout. This week, the California court overseeing the case held a hearing regarding preliminary approval of the settlement, but the judge has not yet issued a ruling. It will likely be at least a few more months before eligible...