Two New Large Sizes for Waterproof Box Sheets: Wide King 200x200 and Family 240x200 to Be Released on Rakuten Ichiba from April 4th at 8 PM
Yugen Kaisha 405 is launching two new large sizes, Wide King 200x200cm and Family 240x200cm, for their "Patto Sheet" waterproof box sheet series on Rakuten Ichiba from April 4, 2026. These new sizes are designed to meet the growing demand for waterproof bedding compatible with larger beds and family sleeping arrangements, addressing common concerns like bedwetting, night sweats, nursing care, and pet cohabitation. The initial release is limited to 30 sheets of each size in gray, with future expansions planned based on market feedback.
📋 Article Processing Timeline
- 📰 Published: April 3, 2026 at 19:00
- 🔍 Collected: April 3, 2026 at 10:30
- 🤖 AI Analyzed: April 17, 2026 at 08:36 (334h 5m after Collected)

Yugen Kaisha 405 (Headquarters: Yokohama City), Director Yoko Oguchi, will release new sizes for its waterproof box sheet series "Patto Sheet": Wide King 200x200cm and Family 240x200cm, on Rakuten Ichiba starting April 4, 2026, at 8 PM.
Sales page:
https://item.rakuten.co.jp/shop405/sheets/
*Sales are scheduled to begin on April 4, 2026, at 8 PM.
Development Background
Waterproof bedding is in demand as a solution for various daily life concerns, such as children's bedwetting, night sweats, nursing care, and cohabitation with pets.
However, there were limited options for waterproof box sheets compatible with large-sized beds or bedroom environments where families sleep together, and there was growing demand for Wide King and Family sizes.
Therefore, our company will expand our existing waterproof box sheet series by adding Wide King 200x200cm and Family 240x200cm, which can accommodate larger bed sizes, to offer a more user-friendly lineup for more households.
Product Features
1. New Sizes for Large Beds
The two new sizes added this time are:
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Wide King: 200x200cm
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Family: 240x200cm
These sizes are easy to use in bedrooms where families sleep together or for households using larger mattresses.
2. Addresses Daily Concerns as a Waterproof Box Sheet
Waterproof box sheets are suitable bedding for those who want to protect their mattress from dirt and moisture.
They can be used for a wide range of purposes, such as children's bedwetting, sweat, stain prevention during nursing care, and living with pets.
3. Easy-to-Use Specification with Integrated Bed Pad
Our waterproof box sheets are designed with an integrated bed pad, making them easy to attach to the bed and simplifying daily bedding management. They are also characterized by their ability to keep the bedding looking neat and being resistant to slipping, making them easy to use.

4. Limited Quantity Release: Gray Only, 30 Sheets Each
These new sizes will be sold in a limited quantity of 30 sheets each, in gray only.
We will first launch with a basic color that is in high demand, and then consider future size and color expansions while observing market response.
Product Overview
Product Name: Waterproof Box Sheet Patto Sheet
Newly Released Sizes:
・Wide King 200x200cm
・Family 240x200cm
Color: Gray
Sales Quantity: 30 sheets each
Release Date and Time: April 4, 2026, 8 PM
Sales Channel: Rakuten Ichiba https://item.rakuten.co.jp/shop405/sheets/
Rakuten Ichiba Store Name: shop405
Recommended for the Following People
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Those looking for large-sized waterproof sheets to sleep with their family.
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Those who want to protect their mattress from children's bedwetting.
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Those looking for waterproof bedding for nursing care.
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Those who want to take measures against dirt when sleeping with pets.
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Those looking for Wide King size or Family size bedding.
Size Comparison
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Wide King 200x200cm
A size that is easy to use for large mattresses or in a bed environment with two beds placed side by side. -
Family 240x200cm
A size suitable for families sleeping together or for a bedroom environment with a wider width.

Frequently Asked Questions
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Q1. What is the difference between Wide King 200x200cm and Family 240x200cm?
Wide King is 200x200cm, and Family is 240x200cm.
The main difference is the width. The Family size is wider and more suitable for families sleeping side by side. -
Q2. What uses are they suitable for?
They are suitable for purposes such as protecting mattresses from dirt and moisture, including children's bedwetting countermeasures, nursing care, living with pets, and night sweat countermeasures.
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Q3. What color variations are available this time?
The new sizes this time are available in gray only.
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Q4. What is the sales quantity?
Each size is limited to 30 sheets.
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Q5. Where can I purchase them?
They are scheduled to go on sale at shop405 on Rakuten Ichiba starting April 4, 2026, at 8 PM.
Sales page: https://item.rakuten.co.jp/shop405/sheets/
Future Developments
Our company will continue to expand the product lineup of the "Patto Sheet" series, emphasizing size variations, ease of use, and addressing lifestyle challenges demanded of waterproof bedding.
We will continue to propose bedding solutions that meet the diverse needs of customers, primarily through Rakuten Ichiba.
[Contact for this release]
Yugen Kaisha 405 Sales Department
2-5-18-31 Chojamachi, Naka-ku, Yokohama City 231-0033
E-mail:sales@405.ne.jp