Aren’t Bath Bombs Getting Expensive Lately?
550 yen for one? That feels steep.
The cheaper bath bombs from 100-yen shops are, well, cheaper, but the toys are meh. My kid doesn’t care, so we stock up for winter to lure them into the bath. But the cheap ones don’t have licensed characters. The pricier ones shout “Kirby!” “Mario!” “Toyota!”—my mood lifts, then crashes at the price. 550 yen, ouch.
Bath bombs have been around for 20 years
First released in 2002!! 『びっくら？たまご』の歴史 - ライフスタイルバンダイ
Did they exist back then? Maybe, but I don’t remember seeing them. Bandai sold them, so maybe toy stores or LOFT? Since I was already an adult, I probably didn’t notice. I likely spotted 100-yen versions first, making Bandai’s look pricey.
But the Kirby package doesn’t say “Bandai.” Instead it lists SK Japan Co., Ltd. and OAK International.
SK Japan handles capsule toys and crane game prizes
They make all those goods you see at Round One. Fits for Kirby.
OAK International makes figures and bath additives
株式会社 OAK インターナショナル | 化粧品・フィギュア・有名キャラクターのグッズ製造会社
The home page shows a bath photo—yep, it’s them. They have factories in China and Thailand. The CEO profile has details:
代表取締役 柏原泰則 | 株式会社 OAK インターナショナル
He also says they’ve made bath bombs for 20 years. Their address is in Asakusa; Bandai is nearby—only a few dozen meters apart.
They don’t warm you up much…
The cheap bath bombs barely color or scent the water and don’t warm me up. Kirby wasn’t much different—color and scent, but no deep warmth.
With “Bub” or hot spring–style additives, I feel warm to the core. With Kirby, hotter water feels warm, but not deeply.
Turns out they’re “bath cosmetics”
Cosmetics! Bath additives, sure, but not medicinal. Bub is an over-the-counter quasi-drug—Japan’s regulated “medicated” category (loosely comparable to an FDA OTC monograph product)—so if you want warmth and relief for shoulder or back fatigue, Bub is better. I felt a bit duped. I expected Kirby to melt away fatigue and fire me up for tomorrow… then realized: these are for kids. Kids don’t have stiff shoulders.
Comparing ingredients
Bub uses baking soda + acid to make high-concentration CO₂—a carbonic acid bath effect that boosts blood flow and whole-body warmth. Sodium sulfate and magnesium sulfate reduce post-bath chill (keeping your body from cooling too fast after the soak), so circulation stays up and recovery improves.
Kirby uses baking soda + citric acid too, but it’s too dilute to affect circulation. The inorganic salts (sodium sulfate, sodium chloride) are minimal, so there’s little anti-chill effect. Made for small kids, so they likely tuned it to “absolutely no adverse effects.” It is, after all, a bath “cosmetic.”
Reference: 入浴剤の成分と種類｜日本浴用剤工業会 - Japan Bath additive Industry Association -
I use bath bombs to bribe the kid into the tub, but I wish they warmed us more. Might have to “additive-top-up” with bath salts.
More from the OAK International CEO
The shoe-salesman story: With two shoe salesmen, one says “Everyone in India is barefoot—shoes won’t sell.” The other says “So few people wear shoes—shoes will sell!” We must always be the latter. People told me for ten years, “Most foreigners shower, they don’t bathe.” (laughs) 代表取締役 柏原泰則 | 株式会社 OAK インターナショナル
“Most foreigners only shower”—it’s true. Japan soaks; many countries shower. Do they really recover that way? In the US many shower in the morning; in tropical Brazil or Vietnam, people shower twice a day. If you bathe multiple times a day, sure, a quick shower. But in colder countries, a tub seems great. Dissolve CO₂, dilate vessels, flush waste—pretty handy. Maybe they use saunas instead? (And yes, Western readers will jump in to say they do take baths!)
Wrap-up
Character-included bath bombs are unusual outside Japan. Random-toy bath bombs cost 100–200 yen, so Kirby or Toyota cars at 550 yen feels… fair. Medicinal ingredients would push the price higher, and these are for kids anyway.
As a bath additive, though, the effect is weak. For fatigue relief, use Bub or other quasi-drug bath additives. Kids don’t have stiff shoulders, so bath bombs are fine for them. If I want a bit more warmth while bathing with my kid, I’ll add a spoon or two of bath salts.
By the way
No secret pull this time. 😢
