Winter 2019: The Divergent Fates of Two Figures Purchased the Same Day
The tips of the twin-tails on the 1/8 scale Hatsune Miku figure standing at the right end of my display case have turned yellow. Of the two figures I acquired together in December 2019 on the same order, the Rem I placed on the left still maintains the sky-blue color from when I opened the box, but only Miku's hair tips—a mere five millimeters—have discolored as if exposed to cigarette smoke. Both are authentic Good Smile Company products, both are PVC material, both were displayed side by side in the same case.
There was only one difference: the distance from the window.
The right end, 1.2 meters from the window. A spot where I'd felt safe assuming direct sunlight wouldn't reach. Five years of believing I'd protected them—drawing curtains, closing the display case door, even blocking dust—left a cruel record on the PVC. Let me give you the conclusion upfront: in arranging a collector's room, the most important factor isn't the angle of lighting or the balanced posing of figures. It's the window's location and what time of day sunlight flows along which wall.
Even Without Direct Sunlight, Five Years Is Sufficient
The belief that "the wall opposite the window is safe" holds only through year two. At 10 AM, light entering through an east-facing window bounces off the living room floor and reaches inside the display case on the opposite wall. It's not direct sunlight. But ultraviolet rays don't die just because they're reflected.
In my case, the window faced southeast and the display case was against the west wall. Mornings were safe. The problem was between 2 and 4 PM, when indirect light reflected from the building across the way entered the room. To the naked eye it just seemed bright, but the figures' PVC began reacting by year two. In year three, subtle cream-colored tints appeared on white parts, and now in year five, it's undeniably yellow.
The community calls this "yellowing," and it became controversial in the mid-2010s when it occurred en masse with certain Alter production lots. But environmental storage conditions cause it more often than manufacturer defects. Among buyers who purchased the same product at the same time, the difference between those who experienced yellowing and those who didn't came down to one thing: their relationship with windows.
Five-Year Color Change Record by Position Inside Display Case
My display case is 120 centimeters wide with four shelves. I recorded changes in twelve figures kept in the same positions from 2019 to 2024. In column 1 on the right end closest to the window, four out of five figures yellowed. In column 2 in the center, one out of six. Column 3 on the left end showed no changes.
The interesting part was height. Even within the right end column, yellowing began in year three on the top shelf four, while the bottom shelf one lasted until year four. Light enters from above and flows downward. The closer a figure is to the ceiling, the sooner it's hit.
For quantitative measurement, starting in 2023 I placed a UV meter (UV-340A, imported from Japan for around 30,000 yen) at various display case positions and recorded daily average UV exposure. The top right end averaged 0.8mW/㎠ per day, while the bottom left end stayed below 0.1mW/㎠. According to American Institute for Conservation (AIC) standards, safe exposure for sensitive materials is below 50,000 lux-hours annually, and my display case's right end exceeded this in just three years.
In numbers, it goes like this: within 1 meter of window + top shelf = 3 years. 1-2 meters + middle shelves = 5 years. Over 2 meters + bottom shelf = 10+ years. This is the time PVC can endure.
![[Bonus] Brown Dust 2 Scheherazade - Code Name S ver. Special Edition w/Acrylic Display Case 1/7 Complete Figure](https://img.yosimarket.com/FIGURE-187278/0?v=6)
[Bonus] Brown Dust 2 Scheherazade - Code Name S ver. Special Edition w/Acrylic Display Case 1/7 Complete Figure →Why Does It Yellow Even With Curtains Drawn?
"But I have curtains up" comes the objection. I believed that too. But ordinary curtains block only 50-70% of UV rays. Even blackout curtains hover around 90%. Not 100%.
In summer 2020, I replaced my existing thin curtains with grade-1 blackout curtains (products labeled 99.9% light blocking). Figures acquired from that winter onward definitely yellowed more slowly. But the yellowing of existing figures already exposed for 2-3 years didn't stop. Once oxidation begins, it's irreversible.
The more shocking truth was the display case itself. Ordinary transparent glass allows 70-80% of UV rays through. Unless it's UV-blocking glass or acrylic, closing the display case door is useless. My case was a DETOLF model purchased from IKEA in 2018, made of ordinary tempered glass. A beautiful but defenseless transparent prison.
Starting around 2021, the community began trending toward modifications where UV-blocking film was applied directly to display cases. The method involves cutting and applying automotive window tint film (99% UV blocking). I had it done in spring 2022, and figures acquired since then show no changes two years later. But Miku's twin-tails, which had already begun yellowing before the film application, remain yellow still.
Is Yellowing Reversible: The Temptation and Cost of Bleaching
The internet floats methods to reverse PVC yellowing using "hydrogen peroxide + UV lamp." It's a technique originating from retro gaming console restoration communities, and it does have temporary effects. But there's a cost.
In fall 2022, I experimented with one yellowed Nendoroid. I soaked it in 12% hydrogen peroxide solution and exposed it to a UV lamp for six hours. The yellow color faded about 70%. I was thrilled. A month later, that part cracked.
Hydrogen peroxide chemically removes the oxidized layer on PVC's surface. The yellowing disappears but the material itself weakens. Thin parts especially (hair, skirt pleats) lose durability and face increased risk of cracking. A Japanese restoration specialist's blog (2020 record) also specifies "effective for console cases but not recommended for precision figures."
Conclusion: yellowing is about prevention, not restoration. Once a figure has yellowed, accepting it as "a souvenir remembering that era's display mistakes" is better for your mental health. Even now, move the position, apply film, replace curtains. For five years from now.
"Azur Lane" I-404 Dance of Crimson Strings Ver. 1/6 Complete Figure Special Edition w/Display Case →Not Display Aesthetics but the Science of Sunlight
Interior design magazines idealize "rooms filled with natural light." To figure collectors, natural light is the enemy. The lessons I've learned over five years are as follows.
First, when arranging your room, place the figure display case not opposite the window but on the same wall as the window—meaning next to it. Light enters frontally and strikes the opposite side. Next to the window is relatively safer.
Second, if possible, choose a north-facing room. Direct sunlight won't enter. If you have a south-facing room, place the case on the north wall; if east-facing, on the west wall. Calculate the angle of light incidence.
Third, arrange the interior of the display case in reverse order of importance. Place your most precious figures in the spot farthest from the window, on the bottom shelf. Position relatively inexpensive items (and those with reissue possibilities) like prize figures or Nendoroids toward the window side. Cold-blooded but strategic sacrifice.
At a Wonder Festival after-event in 2023, one dealer I met said "I bricked up all the windows in my workshop." Extreme, but I understood. To create garage kits still sellable in ten years, sunlight isn't a variable but an enemy.
Are LED Lights Safe: The Duet of Heat and Wavelength
"If natural light is dangerous, can't I just leave LEDs on 24 hours?" No. LEDs also emit ultraviolet rays. Less, but not zero.
Standard white LED UV emission is about 1/100th of sunlight, but 24 hours × 365 days = 8,760 hours of annual exposure changes the story. According to a 2021 Korean Institute of Illuminating and Electrical Installation Engineers paper, certain LED products (especially cheap Chinese ones) emit considerable near-UV radiation in the 400-420nm band, which can cause PVC yellowing.
The bigger problem is heat. Even if LEDs produce little UV, their heat generation cannot be ignored. When display case interior temperature rises, PVC plasticizers seep to the surface in a phenomenon called "bleeding." It becomes sticky, dust adheres, and eventually yellowing follows.
In my experience, safe lighting operation goes as follows. First, choose LEDs with Color Rendering Index (CRI) above 90 and color temperature below 5000K. Second, use a timer to light only 4-6 hours daily. Turn off when sleeping at night or when out. Third, check the display case's internal temperature. If it rises above 30°C in summer, adjust lighting position or output.
"So we live in darkness?" Yes, to some degree. A collector's room should operate like a museum. Turn on lights only when needed, and normally let figures sleep in darkness. Not romantic, but to see the same colors in ten years, you must choose darkness now.
Special Display Case for 1/18 Scale Car x1 "Seibu Keisatsu Super Z" →2024: I've Emptied the Right End
Now column 1 on the right end of my display case sits empty. In spring 2024, I packed the four yellowed figures in separate boxes and stored them deep in a drawer. So they won't worsen further, and so I won't feel regret every time I look.
I decided not to place anything in that spot. Not as empty space but to leave it as a "forbidden zone reminding me of the window's danger." Whenever a new figure arrives, I tell myself "not the right end."
Some collectors consign yellowed figures to secondhand shops. I couldn't do it. Because I remember the excitement of opening the box that first time in winter 2019 and placing them in the display case. I decided to shoulder five years of mistakes and keep them in the drawer. If restoration technology advances someday, maybe I can take them out again then. Baseless hope, but collectors are inherently irrational.
FAQ
Can I stop the progression of yellowing that's already started?
Yes. Immediately move it to a position over 2 meters from the window, apply UV-blocking film to the display case, and install grade-1 blackout curtains. The color already changed won't return, but you can slow further progression by over 90%. Adding silica gel to maintain 40-50% humidity will also prevent plasticizer bleeding.
Do north-facing rooms still risk yellowing?
North-facing rooms are relatively safer due to lack of direct sunlight, but scattered light from the sky (centered on blue wavelengths) still enters. For complete safety, I recommend the combination of north-facing + blackout curtains + UV-blocking film. Even north-facing, a display case directly in front of the window is risky for long-term storage over five years.
Are Nendoroids more resistant to yellowing than scale figures?
The material is identical PVC, so yellowing risk is the same. However, Nendoroids have many interchangeable parts, making it possible to repurchase just a yellowed face part secondhand, and frequent reissues make countermeasures relatively easier. Scale figures rarely get reissued and don't allow partial replacement, so yellowing hits harder when it occurs.
Can I apply UV-blocking film directly to the display case?
Yes. Cut automotive window tint film (3M, LLumar, or other 99% UV-blocking products) to fit the glass size and apply using a mixture of water and neutral detergent. Push out bubbles with a card and let dry for 24 hours. Installation difficulty isn't high, but I recommend trying on practice glass first. After film application, display case transparency drops about 5-10%, but it's not significantly noticeable to the naked eye.
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I hope good fortune reaches your display cases today, and that they remain the same color five years from now as they are today.
