1. Why does the absorbent core determine whether the sanitary pad is good or not?
The surface layer of the serviette hygiénique périodique is responsible for rapid drainage, and the bottom film is leakproof. The key layer that determines “how much to absorb, lock, and no backflow” is the absorbent core. A high-quality absorbent core needs to strike a balance between liquid introduction speed, dispersion, water lock, thickness control, and fit comfort. This is closely related to the material type, fiber structure, SAP distribution method, and core compression process. Industry practice shows that sanitary products generally adopt a multi-layer structure: skin-friendly non-woven surface layer → drainage/distribution layer → absorbent core (fiber + polymer) → leakproof bottom film → viscose fixation.
2. The main material composition and function of the absorbent core are disassembled
1. Fluff pulp (wood pulp / Fluff Pulp)
Fluff pulp comes from softwood/hardwood fibers, which are broken up to form a high-fluff fiber skeleton. It first “eats” the liquid, establishes capillary channels, and provides physical support and uniform distribution space for polymer particles, and can also increase the absorption speed. In actual production, the proportion is often determined according to the origin and fiber length. And even non-wood fiber and mineral fillers are added to improve absorption and molding performance.
2. Super absorbent polymer (SAP, usually cross-linked sodium polyacrylate)
SAP can absorb hundreds of times its own weight of water, and still has the ability to absorb and retain liquid in blood-simulated fluid. After being compressed, it can still partially retain gel water, significantly reducing re-seepage. Mainstream brands (such as Always) also list “sodium polyacrylate” as one of the absorbent materials in the formula table.
3. Airlaid absorbent paper / composite absorbent layer (Airlaid + SAP composite)
To balance thinness and absorption capacity, the industry often combines SAP with fluff pulp, tissue paper, or airlaid absorbent paper into sheets. Thick sheets can wrap SAP + fluff pulp. Thin solutions use airlaid substrates combined with SAP distributed in dots to improve laying uniformity and core integrity, which is suitable for ultra-thin sanitary napkins.
4. Diversion/distribution layer (ADL) and core wrap
The non-woven diversion layer helps liquids quickly penetrate the surface layer and diffuse laterally, reducing concentrated overflow. The core wrap structure (core wrap) can stabilize the absorbent particles and inhibit powder migration, improve dryness, and structural strength. And is an important design detail for high-performance sanitary napkins.
3. Our Childsea customizable sanitary napkin absorbent core solution
Product name: Day Use Disposable Sanitary Napkins (Brand: I’ve Girl / I’ve Care / OEM/ODM).
Size: Daily standard 220–260mm, customizable according to market, with wings.
Thickness: Optional ultra-thin/thickened.
Main materials (configured according to user needs): Dry and soft surface non-woven; air-laid absorbent paper; imported American fluff pulp; Japanese Sumitomo grade SAP (blood absorption grade optional); breathable color-printed PE bottom film; printed release paper; independent small package/color bag outsourcing.
Functional chip (optional): negative ion, nano silver, magnetic powder, graphene, chitin, far infrared, etc.; support customization.
Absorption capacity: calibrated according to market level (light/medium/added); the laboratory can simulate fluid testing according to customer standards.
Packaging: 10 pieces/bag or customized multiple pieces combination.
Production capacity: about 4,200,000 pieces per day; delivery time: 25–30 days after receiving a 30% deposit; samples: free.
Origin: Quanzhou, Fujian, China.
If you need to customize the absorbent core formula or obtain a specification sheet, or large sanitary napkins, please leave a message or nous contacter directly through the official website.
4. Purchase and testing: How to verify whether the absorbent core meets the standards?
1. Absorption and leakage test
The laboratory can quantitatively perfuse simulated menstrual blood (colored water or animal blood standard solution) to determine the volume before complete absorption, leakage point, and absorption rate; UNFPA assistance specifications require perfusion at a rate of 15 ml/min and observation of bottom and side leakage.
2. Absorption rate (Strike-Through) and rewet (Rewet)
The faster the absorption, the drier the surface layer remains; the rewet index measures the degree to which the liquid returns to the surface under pressure, which is the key to comfort; industry laboratories often provide rewet and back permeation tests.
3. pH, raw materials, and safety compliance
UNFPA specifications recommend a pH of 6–8.5 for the finished product extract; China GB/T 8939 and other national standards provide reference standards for raw materials (fluff pulp, super absorbent resin, air-laid paper, surface material) and test methods such as absorption speed and peel strength; these indicators help you verify whether the sanitary napkin absorbent core material complies with the regulations of the target market.
Summary
The sanitary napkin absorbent core is usually composed of a fluff pulp fiber skeleton + super absorbent polymer (SAP), supplemented by air-laid absorbent paper, a guide layer and core coating technology to achieve a comprehensive performance of “fast absorption – water lock – anti-re-seepage”; different markets have different preferences for size, absorption level, functional chips and environmental protection properties, bringing a wide range of customization space. Childsea can flexibly sample in terms of size, material ratio, functional chips, and packaging according to customer market needs, helping brands quickly land highly competitive sanitary napkin products.