Anti-blocking Precipitated Silica | Film Opening Agent for BOPP PE PP PET Films Manufactured by Shandong Zhonglian Chemical Co., Ltd. Get reliable anti-blocking performance for plastic films with our high-purity precipitated silica. Engineered as a professional film opening additive, it effectively eliminates layer adhesion during winding, storage and unwinding, while preserving excellent optical clarity and mechanical properties of films. Ideal for packaging film producers, masterbatch manufacturers and OEM/ODM oral care & plastic enterprises. Get Latest Price · Contact Now for Samples Product Information The Anti-blocking Precipitated Silica from Shandong Zhonglian Chemical Co., Ltd. is a functional amorphous hydrated silica specially developed for the plastic film and masterbatch industry. It is designed to solve the common blocking problem of polyolefin and polyester films, providing a stable and efficient opening solution for high-speed film production lines. Inside the product, uniformly sized micro silica particles form regular micro-protrusions on the film surface during film forming, which physically separate the upper and lower film layers, reduce the contact area between films, and fundamentally prevent inter-layer adhesion caused by pressure and heat during winding. The soft particle morphology will not scratch the film surface or damage the gloss of the product. This opening silica adopts advanced precipitation process control, with ultra-high whiteness and extremely low heavy metal residue. It maintains chemical inertness in most polymer resin systems, does not react with active additives such as slip agents and antioxidants, and has no negative impact on the heat sealing performance, tensile strength and elongation of the finished film. Our production base operates under a strict GMP quality management system, and each batch of products has full traceability from raw ore mining to finished powder packaging. We provide a complete set of technical documents and regulatory certification materials to support customers' product formula development, factory audit and global market access. Product Appearance White amorphous powder with uniform particle size, no agglomeration and no impurities. It can be uniformly dispersed in polyolefin and polyester resin systems, and is suitable for twin-screw extrusion masterbatch making and direct film extrusion production. Product Parameters 表格 Item Specification SiO₂ Content (Ignited Basis) ≥ 97.5% Loss on Ignition (1000℃, 1h) ≤ 8.0% Moisture (As Packed, 105℃, 2h) 3.0 – 5.5% pH (5% Water Suspension) 6.5 – 7.3 Bulk Density 0.20 – 0.28 g/cm³ DBP Oil Absorption 80 – 120 cm³/100g Median Particle Size (D50) 3 – 7 μm BET Surface Area 100 – 140 m²/g Whiteness (CIE L*) ≥ 97.5 Heavy Metal Limits Arsenic ≤1ppm, Lead ≤2ppm, Mercury ≤0.5ppm Total Aerobic Plate Count ≤ 50 cfu/g Core Material Amorphous precipitated hydrated silica Primary Application Film anti-blocking / opening agent, plastic masterbatch additive Product Features 1. Controlled Particle Morphology & Uniform Dispersion Adopting narrow particle size distribution control technology, the product has regular particle shape and uniform size. It can be uniformly dispersed in the resin matrix during extrusion processing, avoiding film defects such as fish eyes, crystal points and streaks caused by particle agglomeration. 2. High Purity & Low Haze Performance Ultra-high SiO₂ purity and low impurity content ensure minimal impact on film light transmittance and haze. The whiteness L* is as high as 97.5, which will not cause yellowing or color cast of transparent films, and maintains the original gloss and appearance of the product. 3. Excellent Resin Compatibility Chemically inert amorphous silica structure, compatible with PP, PE, BOPP, PET and other common polymer materials. It can be used together with slip agents, antioxidants and light stabilizers without affecting the efficacy of other additives. 4. Stable Batch-to-batch Consistency Full online monitoring of particle size, oil absorption and whiteness in the production process, strict quality control of each production link, to ensure that the performance of each batch of products is highly consistent, and reduce the repeated adjustment of customers' production formulas. 5. Food Contact Grade Safety Strictly control heavy metals and microbial indicators, in line with global food contact material safety standards. It is suitable for food packaging film production scenarios with high hygiene requirements. Core Advantages Reliable & Long-lasting Anti-blocking Effect The physical opening mechanism formed by micro-spacer particles is not affected by temperature and humidity changes. Even under the pressure of long-term storage and high-temperature transportation, it can still maintain stable anti-blocking performance, and solve the problem of difficult unwinding of film rolls. Versatility Across Film & Masterbatch Applications Whether it is BOPP biaxially oriented film, cast PP film, LDPE blown film, PET polyester film, or functional anti-blocking masterbatch production, this product can be well adapted. We support customized particle size and oil absorption indicators according to different film thicknesses, processes and performance requirements to meet diversified production needs. Usage & Storage Instructions 1.Recommended addition ratio: 0.1% – 0.5% in the finished film formula; 3% – 8% when used to prepare anti-blocking masterbatch. The specific dosage can be adjusted according to the target film thickness and anti-blocking grade. 2.It can be used alone, or blended with slip agent silica or other additives to balance the opening performance and sliding performance of the film. 3.It is recommended to add it in the dry powder mixing stage of masterbatch production, and fully disperse it with the carrier resin under twin-screw extrusion to ensure uniform distribution in the system. 4.To achieve the best anti-blocking effect, avoid particle moisture absorption and agglomeration during feeding and processing, and ensure good dispersion of the powder in the resin melt. 5.Storage requirements: Store in a cool, dry and ventilated warehouse, seal the packaging after opening, avoid moisture absorption and dust contamination, and the shelf life is 24 months under unopened conditions. Application Scenarios BOPP Food Packaging Film Suitable for various BOPP packaging films such as ordinary packaging film, heat-sealing film and cigarette packaging film, which solves the problem of roll sticking in high-speed production and meets the requirements of high transparency and food contact safety. PE / PP Blown & Cast Film Widely used in LDPE blown film, cast PP film, agricultural mulch film, shopping bag film and other fields, providing stable opening performance and good film surface quality. PET Polyester & Lamination Film Adapted to PET film and composite lamination film production, with low haze and high gloss characteristics, to meet the strict optical performance requirements of high-end packaging films. Anti-blocking Masterbatch Production Ideal for functional masterbatch manufacturers, with good dispersion and stable batch quality, supporting the production of various concentration of opening masterbatch products. Frequently Asked Questions Q1: What is anti-blocking silica and how does it work? A: Anti-blocking silica is an amorphous precipitated silica used as a film opening additive. It forms micro-protrusions on the film surface to physically separate film layers, preventing adhesion during winding and storage. Q2: Which types of films is this product suitable for? A: It is suitable for BOPP, cast PP, LDPE blown film and PET packaging film, and can also be used for the production of anti-blocking functional masterbatch. Q3: What certifications do you have for this silica? A: Our products have ISO 22000, GMP, HALAL, KOSHER, REACH certification and FDA food contact material approval, which can meet the regulatory requirements of most global markets. Q4: Can you customize product specifications? A: Yes. We can adjust D50 particle size, DBP oil absorption and other indicators according to customers' film formula and performance requirements. Q5: What is the recommended addition amount? A: 0.1% – 0.5% in the finished film; 3% – 8% in the anti-blocking masterbatch. The specific dosage can be adjusted according to actual test results. Q6: What technical documents can you provide? A: We can provide complete documents such as TDS, MSDS, COA, particle size distribution report and regulatory certification to support customers' product development and registration. Q7: What are the packaging and trade terms? A: Standard export packaging is 10/15/20kg waterproof kraft paper bags. Trade terms support FOB Qingdao, CIF destination port and DDP. Version 2 ｜ 高透明薄膜专用版（主打低雾度、高端 BOPP/PET 膜） High-Clarity Anti-blocking Silica | Premium Opening Agent for BOPP & PET Films Manufactured by Shandong Zhonglian Chemical Co., Ltd. High-performance precipitated silica designed for premium high-transparency packaging films. Delivers reliable anti-blocking efficiency with minimal haze increase, preserving maximum gloss and clarity for high-end BOPP food packaging film and PET lamination film. Request Technical Data · Order Samples for Film Test Product Information Shandong Zhonglian Chemical Co., Ltd. developed this high-clarity grade anti-blocking silica specifically for the production of high-transparency plastic films. Aiming at the pain point that traditional opening agents easily increase film haze and reduce gloss, we adopt precision particle size control technology to achieve the optimal balance between opening performance and optical performance. Different from ordinary silica with wide particle size distribution, this product uses a narrow-distribution particle design. All particles are controlled within a very small size range, avoiding the formation of large-sized scattered particles that cause light scattering, thus minimizing the haze increase of the film and maintaining high light transmittance and surface gloss. The ultra-fine and uniform spherical particles form a neat micro-spacer structure on the film surface, which effectively separates the film layers and solves the blocking problem of high-gloss films during high-speed winding and long-term storage. At the same time, the particles have good roundness, which will not scratch the film surface or affect the printing and heat sealing properties of the film. This product strictly controls impurity ions and heavy metal content, with ultra-high whiteness, which will not cause yellowing or color deviation of the film. It complies with global food contact safety standards and is fully suitable for high-end food packaging, cosmetic packaging and other scenarios with high appearance requirements. Product Appearance Ultra-white fine amorphous powder, no agglomeration, no visible impurities. After being added to the film, it has no effect on the transparency and appearance of the film, and maintains the original high-gloss effect of the resin. Product Parameters 表格 Item Specification SiO₂ Content (Ignited Basis) ≥ 97.5% Loss on Ignition (1000℃, 1h) ≤ 8.0% Moisture (As Packed, 105℃, 2h) 3.0 – 5.0% pH (5% Water Suspension) 6.5 – 7.3 Bulk Density 0.22 – 0.28 g/cm³ DBP Oil Absorption 90 – 120 cm³/100g Median Particle Size (D50) 3 – 5 μm BET Surface Area 110 – 140 m²/g Whiteness (CIE L*) ≥ 97.5 Heavy Metal Limits Arsenic ≤1ppm, Lead ≤2ppm, Mercury ≤0.5ppm Total Aerobic Plate Count ≤ 50 cfu/g Core Material Amorphous precipitated hydrated silica Primary Application High-clarity BOPP/PET film, premium packaging film opening agent Product Features 1. Narrow Particle Size Distribution & Ultra-low Haze Precision graded particle size control ensures extremely narrow particle distribution, effectively reduces light scattering, and minimizes the haze increase of the film while ensuring anti-blocking performance. 2. Spherical Particle Morphology & High Gloss Retention Nearly spherical particle shape, uniform distribution on the film surface, no damage to the film surface gloss, maintaining the high-gloss and high-transparency effect of premium films. 3. No Surface Defects Strict screening and depolymerization process, no large agglomerated particles, effectively avoiding fish eyes, crystal spots and bright spots on ultra-thin films, and improving the excellent product rate of high-speed film production lines. 4. Good Compatibility with Optical Brighteners Chemically inert, does not react with optical brighteners and color masterbatches, does not affect the whitening and color rendering effect of the film, and is suitable for various high-appearance film formulations. 5. Food Contact Grade Safety Guarantee Strictly control heavy metals and microorganisms, meet FDA, EU food contact material standards, suitable for high-end food packaging and health product packaging film production. Core Advantages Optical Performance Leading the Industry Compared with ordinary opening silica, this high-clarity grade can reduce the haze increase by more than 30% under the same addition amount and anti-blocking effect, helping customers produce film products with higher clarity and gloss and enhance product competitiveness. Adaptable to Various High-end Film Processes Whether it is BOPP biaxial stretching, PET casting or multi-layer co-extrusion lamination film process, this product can maintain stable performance. It supports customized finer particle size grades for ultra-thin films below 15μm to meet more stringent optical requirements. Usage & Storage Instructions 1.Recommended addition ratio: 0.12% – 0.4% in high-transparency BOPP/PET finished film; 4% – 7% when preparing high-clarity opening masterbatch. Adjust according to actual film thickness and haze target. 2.It can be used in combination with slip agent to achieve the best balance of opening performance, sliding performance and optical performance. 3.Ensure that the powder is fully dried before use, and adopt a good side feeding and dispersion system to avoid particle agglomeration affecting the film appearance. 4.In the masterbatch production process, it is recommended to use a twin-screw extruder with good dispersing effect to ensure uniform dispersion of silica in the carrier resin. 5.Storage: Strictly sealed and stored in a dry environment to prevent moisture absorption from causing particle agglomeration and affecting the use effect. Application Scenarios Premium BOPP Food Packaging Film Suitable for high-transparency BOPP food packaging film, cigarette packaging film, heat-sealing composite film, etc., to meet the dual requirements of high-speed production anti-blocking and high-gloss appearance. High-gloss PET Lamination Film Used in PET polyester film and composite lamination film production, maintains high clarity and gloss, and is suitable for high-end packaging such as cosmetics, electronics and food gift boxes. Ultra-thin CPP Cast Film Adapted to the production of ultra-thin cast PP film, provides stable opening effect without affecting the transparency and heat sealing performance of the film. High-end Film Masterbatch Special for high-clarity anti-blocking masterbatch production, helping masterbatch manufacturers produce high-end masterbatch products with low haze and high opening efficiency. Frequently Asked Questions Q1: Why is this silica suitable for high-clarity BOPP film? A: It adopts narrow particle size distribution control to minimize light scattering, so it can ensure anti-blocking effect while bringing minimal haze increase and maintain high film transparency. Q2: Will this product cause spots or fish eyes on thin BOPP film? A: Strict powder depolymerization and screening process removes large agglomerated particles. With proper dispersion process, it will not produce visible film defects. Q3: What particle size grade is recommended for ultra-thin BOPP film? A: For ultra-thin high-transparency BOPP film below 15μm, we recommend finer grade with D50 of 3 – 4.5μm, which can be customized according to your test requirements. Q4: Does it affect the heat sealing performance of BOPP film? A: The amorphous silica is chemically inert and will not adversely affect the heat sealing strength and sealing appearance of the film. Q5: Can it be used for PET lamination film? A: Yes, it is compatible with PET resin system and can meet the strict optical performance requirements of lamination film. Q6: What is the whiteness index of this product? A: The whiteness CIE L* is ≥ 97.5, with extremely low impurity content, which will not cause yellowing of the film. Q7: Can you provide haze test data of the film? A: Yes, we can provide the haze test data of the film prepared with different addition amounts for your reference and formulation debugging.