Overview
Kaolin refractory clay, also known as china clay, is a naturally occurring aluminosilicate mineral widely used in industries such as papermaking, ceramics, and refractory materials. Its high heat resistance and fine particle size make it particularly valuable for coating and filling in paper production. In papermaking, kaolin enhances brightness, opacity, and printability. The material's chemical inertness ensures compatibility with other paper additives, while its platy particle structure improves sheet formation and ink receptivity.
Physical and Chemical Properties
Kaolin exhibits a characteristic white color due to its high purity, though impurities may cause slight discoloration. The material's platy particle structure contributes to its excellent covering power in paper coatings. With a Mohs hardness of 2-2.5, it's relatively soft compared to other industrial minerals. Chemically, kaolin is stable under normal conditions but transforms into metakaolin when heated above 550°C. Its low conductivity and high dielectric strength make it valuable for specialty paper applications. The material's specific surface area typically ranges between 10-30 m²/g, influencing its performance in paper coatings.
Main Applications
In paper manufacturing, kaolin serves three primary functions: as a coating pigment to enhance surface properties, as a filler to improve opacity and brightness, and as a processing aid to control rheology. The paper industry accounts for approximately 40% of global kaolin consumption. Beyond papermaking, this material finds use in ceramic production, where it contributes to whiteness and plasticity. In refractory applications, kaolin's high fusion temperature makes it suitable for furnace linings and insulation materials. Recent developments have expanded its use in advanced materials like nanocomposites and catalysts.
Safety and Storage
While kaolin is generally considered non-toxic, prolonged inhalation of dust may cause respiratory irritation. Appropriate personal protective equipment including dust masks and eye protection should be used during handling. The material poses no significant fire hazard due to its non-combustible nature. Storage recommendations include keeping kaolin in sealed containers or covered silos to prevent moisture absorption. Bulk storage should be in dry areas with adequate ventilation. Shelf life is typically indefinite if stored properly, though caking may occur in humid conditions.
B2B Procurement Guide
When sourcing kaolin for papermaking, buyers should specify parameters including particle size distribution (typically 80-90% <2μm for coating grades), brightness (minimum 85% ISO), and viscosity characteristics. Iron and titanium oxide content significantly affect end-use performance and should be below 0.8% and 1.2% respectively for premium applications. Procurement professionals should consider transportation costs, as kaolin's bulk density affects shipping economics. Establishing long-term contracts with suppliers can help stabilize pricing, while quality audits of mining and processing facilities ensure consistent material characteristics. Technical support from suppliers for application testing is valuable for optimizing formulations.
Related Manufacturers
- 主营：超细硅酸铝粉、硅藻土、膨润土、高岭土、滑石粉、彩砂、透明粉、白炭黑、金刚砂、石墨、海泡石、木粉、轻钙、重钙、玻璃粉、贝壳粉、凹凸棒土、玻璃鳞片、陶土、铝矾土、火山岩、电气石粉、合成云母、赤铁粉
- 主营：变压器鹅卵石、石英砂、火山石、煅烧高岭土、彩色石子、鹅卵石滤料、夜光石、黑色金刚砂、黑色砾石、白色石子、地坪五彩石、烘干砂、贝壳粉、重钙粉、轻钙粉、石英粉、滑石粉、水洗石、水磨石子
- 主营：石墨粉、氢氧化钙、石英砂、超细煅烧高岭土、石英粉、硅微粉、硅酸钾、玻璃纤维布、水玻璃、辉绿岩铸石粉、环氧树脂、环氧树脂固化剂、活性炭、消石灰、耐高温耐磨材料、钾水玻璃、耐高温涂料、玻纤布、泡花碱、辉绿岩粉、耐酸水泥、玻璃丝布
- 主营：重质碳酸钙、碳酸钙、滑石粉、高岭土、海泡石、石灰石、硅藻土、一级矿粉、萤石矿石、活性钙、沉淀硫酸钡、氢氧化钙、氧化钙、膨润土、透明粉、硅酸铝粉、贝壳粉、彩砂、轻钙、萤石粉、水镁石、矿粉、铸石粉、浴沙、金玉明砂
- 主营：蛭石、硅藻土、椰糠、高岭土、稻壳碳、金刚砂、玻璃粉、麦饭石、火山石、重晶石、白炭黑、玻璃砂、贝壳粉、氧化铁、重钙、沸石
- 主营：耐火材料、硅藻土粉、白云石粉、高岭土、贝壳粉、滑石粉、石英砂、金刚砂、碳酸钙、玻璃微珠、石墨粉、远红外粉、石英粉、麦饭石粉、沸石粉、重钙粉、轻钙粉、高纯负离子液、膨润土、赤石脂粉、鹅卵石雨花石、彩色石子、活性白土、膨胀石墨、硅酸锆
- 主营：石英粉、滑石粉、石英砂、高岭土、无机凝胶、硅灰石粉
- 主营：重钙粉、轻钙粉、滑石粉、煅烧高岭土、膨润土、活性钙、硅灰、硅藻土、绿泥石粉、伊利石粉、白云石粉、石英粉、重晶石粉、活性白土、灰钙、变压器鹅卵石、彩色石子、金刚砂
- 主营：耐火浇注料、酸性炉衬材料、高效除渣剂、高岭土、铝矾土高铝细粉、石墨化增碳剂、透热炉打结料、线圈胶泥、中性炉衬材料、导电粉、中间包可塑料、打炉料、干振料、刚玉炉衬料、硅藻土、电气石托玛琳粉、膨润土、重晶石硫酸钡粉、蛭石、橡胶颗粒粉、石英沙石英粉、绿泥白泥修补料、凹凸棒土、重质轻质碳酸钙、雨花石炉料
- 主营：硅灰石粉、矿粉、硅灰、高岭土、长石粉、玻璃粉、膨润土、玻璃鳞片、萤石粉
- 主营：玻璃鳞片、玻璃粉、膨润土、高岭土、煅烧高岭土、滑石粉、铝矾土、硅灰、萤石粉、沉淀硫酸钡、重钙、轻钙、硅藻土、珍珠岩、玻璃微珠、重晶石粉、S95矿粉、透明粉、玻璃砂、云母粉、木炭、硅酸铝粉、长石粉、火山石、贝壳粉
- 主营：重钙粉、白云石、石英砂、高岭土、偏高岭土粉、金刚砂、陶土粉、重晶石粉、石英粉、膨润土、橡胶粉、铝矾土、麦饭石粉、蛭石、滑石粉、轻质碳酸钙、凹凸棒土、长石粉、粘土球、白云石粉、硅微粉、珍珠岩粉、氧化钙、氢氧化钙
- 主营：润滑剂、石墨粉、超细石墨粉、煅烧高岭土、耐火泥造纸、高岭土、阻燃石墨、超细石墨、高纯石墨、润滑石墨铅粉、合成氟金云母粉、种子包衣粉、麦饭石粉、白色电气石粉、远红外粉、导电石墨粉、耐高温石墨粉、云母片、天然云母片、耐高温云母片、透明云母片、云母板、沸石、沸石粉、麦饭石颗粒
- 主营：轻质碳酸钙、4A沸石粉、膨润土、煅烧高岭土、水洗高岭土、重晶石粉、配重铁粉 铁砂、氢氧化钙、红陶土 黄陶土、木粉、麦饭石粉、沸石粉、滑石粉、负离子粉、硅藻土、白云石粉、玻璃鳞片、高铝耐火粉、蓝晶石粉
- 主营：石墨、膨胀石墨、导电石墨粉、改性高岭土、防静电墨粉、阻燃石墨粉、鳞片石墨粉、超细石墨粉、云母、云母片、茶色云母片、云母粉、电气石、电气石粉、电气石颗粒、天然云母片、透明云母片、导热石墨、绝缘云母片、耐高温云母、云母板、岩片、贝壳片、膨润土、钙基膨润土、纳基膨润土