Hollow Conjugated Siliconized Fiber: The Ultimate Pillow Filling
Everything you need to know about choosing, using, and caring for the best synthetic pillow filling on the market — softer, longer-lasting, and hypoallergenic.
The quality of a pillow starts from the inside. Filling composition determines everything — support level, comfort, breathability, and how well the pillow holds its shape over time. Among all synthetic filling options available today, hollow conjugated siliconized fiber stands out as the top-performing choice for pillows and cushions alike.
This guide covers what the fiber is, how to use it correctly, and why it outperforms both traditional polyester and natural down alternatives.
What Is Hollow Conjugated Siliconized Fiber?
Hollow conjugated siliconized fiber is a type of polyester staple fiber engineered through a process called conjugate spinning — combining two polymers of different viscosity into a single filament. Because these polymers elongate and crystallize at different rates, the resulting fiber develops a natural, three-dimensional crimp similar to that found in wool.
Three core technologies are combined in one fiber:
Hollow cross-section — a tube-like structure that traps air for warmth and lightweight feel.
Conjugation — the bi-component spinning that creates permanent, resilient crimp.
Siliconization — a silicone-oil coating that makes fibers smooth, tangle-free, and resistant to bacteria.
Together, these properties give the fiber exceptional elasticity, loft, and durability — qualities that traditional hollow staple fibers cannot match.
Available Sizes & Recommended Use
For pillow manufacturers who need a balanced filling fiber with softness, resilience and stable bulkiness, HEDA supplies 7D hollow conjugated siliconized fiber in 32mm, 51mm and 64mm cut lengths for pillows, cushions, sofas, toys and mattresses.
Our hollow conjugated siliconized fiber is manufactured in three denier sizes, each suited to a different pillow feel:
| Denier (D) | Length Options | Best For | Pillow Feel |
|---|---|---|---|
| 3D | 32 mm / 51 mm | Soft, luxury pillows | Plush & cushy |
| 7D | 32 mm / 51 mm / 64 mm | Everyday bed pillows | Medium & supportive |
| 15D | 51 mm / 64 mm | Firm support pillows | Dense & structured |
A standard 5 kg package yields approximately 10–14 standard throw pillows (14×14 in) or two extra-large floor pillows — making it cost-effective for both home DIY projects and small-scale production.
How to Fill a Pillow Correctly
The fiber arrives factory-ready — no additional treatment required. Simply stuff it into a pre-sewn pillow form made from foam or spun-bonded fabric, then insert the filled form into your pillow cover. Keep the following three tips in mind for best results:
Filling Method
Machine filling produces a more uniform, fluffy result. Manual stuffing works but may create uneven density. Use a machine whenever possible.
Amount of Fiber
Overfilling makes a pillow stiff and reduces its spring-back. Aim for a medium fill — the fiber should compress and recover freely under pressure.
Fill Power
600–800 g is the ideal medium-fill range for most pillow sizes. Exceeding 800 g results in a pillow that is too rigid for comfortable sleep.
Key Advantages Over Other Fillings
- Retains shape far longer than traditional hollow staple fiber — no flattening or hollowing out with regular use
- Lightweight yet supportive — provides the right amount of loft without added weight
- Silky smooth texture thanks to the silicone-oil coating, for a comfortable sleep surface
- Tangle-free structure prevents lump formation inside the pillow
- Breathable hollow core promotes airflow, keeping you cool through the night
- Resists dust mites, mold, and bacteria — ideal for allergy-sensitive users
- Hypoallergenic — the safest down alternative for those with feather allergies
- Low maintenance — no fluffing needed and fully machine washable
- Long lifespan — with proper care, retains quality for up to 3 years
Looking for a premium pillow filling that's soft, durable, and hypoallergenic? Hollow conjugated siliconized fiber delivers on every front — from the factory to your bedroom.
Need a firmer pillow or cushion filling option?
Besides 7D soft filling fiber, HEDA also supplies 15D hollow conjugated siliconized fiber for firm support pillows, bedding, sofas and mattress filling.
