Elvanol 71-30

1. Mechanism of Elvanol in Paper Surface Treatment In the modern paper industry, surface treatment has become an important means of increasing the added value of paper. Printability, surface strength, and barrier properties against oils and solvents all highly depend on the material selection of the surface sizing or coating system. Elvanol polyvinyl alcohol, as a high-performance water-based film-forming material, is widely used in paper surface treatment.     Elvanol is a fully or highly hydrolyzed polyvinyl alcohol with excellent film-forming ability. Its regular molecular chain structure allows it to form a continuous and dense film during drying, significantly improving the surface strength and barrier properties of the paper. Compared to using starch alone, the film formed by Elvanol is tougher, has stronger chemical resistance to oils, waxes, and solvents, and exhibits higher water resistance.   Using Elvanol in the sizing press or calendering stage can significantly improve the paper's resistance to linting, dusting, and cracking. Even at low addition levels (approximately 10% solids content), it can achieve surface strength and folding strength superior to traditional starch systems. This characteristic makes it particularly suitable for high-filler paper, recycled fiber paper, and paper types requiring high printability.   In addition, Elvanol has good compatibility and can coexist stably with modified starch, CMC, alginates, wax emulsions, and common papermaking additives, providing greater flexibility for papermaking process adjustments.   2. Application Advantages of Elvanol in Improving Barrier, Strength, and Printing Performance ♣ Surface Barrier Properties Elvanol is one of the most powerful water-based barrier film-forming materials in the paper industry. The film it forms has a natural barrier effect against oils, greases, and organic solvents, and is therefore often used in applications such as greaseproof paper, oil-resistant packaging paper, and copier paper. In oil-resistant systems, Elvanol can also serve as an effective carrier for fluorochemicals, improving the stability and efficiency of the overall barrier system.   ♣ Surface Strength and Structural Stability Compared to starch-sized paper, paper treated with Elvanol exhibits superior resistance to surface abrasion, cracking, and linting. Its high bonding strength effectively binds fibers and fine surface particles, reducing linting and dusting, thereby lowering the frequency of blanket contamination and downtime for cleaning during printing. This advantage is particularly evident in high-speed offset printing and high-precision printing. At the same time, Elvanol allows for a higher proportion of fillers or recycled fibers while maintaining strength, helping paper mills control costs while maintaining paper performance.   ♣  Printability and Coating Suitability Elvanol-treated paper surfaces are smoother and have excellent ink holdout. Due to its oil and solvent resistance, ink does not easily penetrate the paper base, resulting in higher print gloss and image clarity. In pigment sizing systems, Elvanol, as a binder, exhibits significantly stronger binding power than acrylic emulsions, styrene-butadiene latex, casein, and starch, and can replace traditional binders at certain ratios, optimizing the pigment/binder ratio.   3. Typical Elvanol Grades and Application Characteristics in Papermaking Based on different paper types and process requirements, we offer a variety of product grades with different viscosities and structures. The following are commonly used grades in the papermaking industry and their application characteristics: Grade Polymer Type Viscosity Level Key Functions Typical Uses Elvanol 71-30 Fully hydrolyzed PVOH Medium Film forming, binding, grease resistance Surface sizing; FWA carrier; lint and dust control; grease-resistant papers Elvanol 80-18 Fully hydrolyzed PVOH Medium Grease barrier, high solids stability Grease-proof packaging papers; high-solids sizing and coating Elvanol 75-15 Fully hydrolyzed PVOH Medium–Low Binder reinforcement Starch reinforcement; lint reduction; high-solids sizing and coating   In optical brightening systems, Elvanol acts as a carrier for fluorescent whitening agents (FWAs), significantly improving whitening efficiency. Adding Elvanol at 0.5–2.5% of the pigment weight in pigment systems results in significantly better whitening effects than using FWA alone, while also reducing the amount of traditional carriers such as starch and casein.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Food and consumer goods packaging is undergoing significant technological upgrades. On the one hand, the market demands longer food shelf life and reduced reliance on preservatives; on the other hand, sustainable development and regulatory compliance are driving the transformation of packaging materials towards recyclability and biodegradability. In this context, the demand for barrier properties in paper and cardboard packaging has increased significantly, especially in terms of oxygen, grease, and mineral oil barrier properties. Traditional plastic films (such as PE and PP) have limited oxygen barrier performance, while multi-layer composite materials, although offering excellent performance, increase the difficulty of recycling and compliance. In contrast, water-based barrier coatings can significantly improve the functionality of the material without significantly altering the paper substrate structure, giving paper packaging performance close to that of high-barrier materials while maintaining good recyclability. Among the many water-based barrier materials, polyvinyl alcohol (PVOH) system coatings have become an important solution for current paper-based packaging barrier technology due to their excellent oxygen and grease barrier properties and mature industrial application base. The KURARAY POVAL (POVAL 6-98), ELVANOL, and EXCEVAL series of products are representative material systems based on PVOH.   1. PVOH Barrier Mechanism and Performance Advantages in Paper Packaging Polyvinyl alcohol is a non-ionic, water-soluble, linear crystalline polymer, whose molecular chains can form a large number of hydrogen bonds. This highly ordered molecular arrangement makes it difficult for oxygen molecules to diffuse, which is the fundamental reason for its excellent oxygen barrier performance. Under suitable coating and drying conditions, the PVOH coating can form a dense and continuous film layer, thereby significantly reducing the oxygen transmission rate (OTR) of the paper substrate material. In addition, the hydrophilic nature of PVOH makes it equally outstanding in blocking grease and mineral oil, which is particularly crucial for the packaging of bread, coffee, baked goods, etc. By coating ordinary starch-based paper with EXCEVAL HR-3010, with a coating weight of only 7 g/m², the OTR (Oxygen Transmission Rate) can be reduced from >2000 mL/m²/d to <1 mL/m²/d (23℃, 50% RH), demonstrating extremely high barrier efficiency.   ♠ Compared to other common barrier materials, PVOH is a leading material in terms of oxygen barrier performance: Polyethylene, Polypropylene: Weak barrier PET, PA6: Medium barrier PVDC: High barrier but with environmental concerns EVOH / PVOH: Extremely high oxygen barrier performance   At the same time, PVOH has been certified by BfR and FDA for food contact regulations, making it safe for use in food packaging systems, which is an important prerequisite for its widespread use in the packaging coating field.   2. PVOH Barrier Coating Product System and Typical Performance Parameters We offer a variety of PVOH product models suitable for paper-based packaging barrier coatings. Different models vary in viscosity, barrier focus, and application suitability, allowing for selection based on actual needs. The following is a performance comparison table: From an application perspective, low-viscosity models (such as EXCEVAL AQ-4104) are more suitable for high-speed coating or low-coating weight systems, while high-viscosity models (such as ELVANOL 71-30) are beneficial for forming thicker, denser barrier layers. The above products are compatible with various common coating processes, such as blade coating, gravure coating, or curtain coating, and have good process compatibility.   In summary, water-based barrier coatings based on PVOH provide a well-balanced solution for paper-based packaging in terms of performance, sustainability, and regulatory compliance, especially suitable for food packaging scenarios sensitive to oxygen and grease.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

The main raw material of polyvinyl alcohol (PVA) is vinyl acetate. PVA(PVA 100-27S & PVA 1799S) is made from vinyl acetate by polymerization and alcoholysis. Downstream, it is used to manufacture polyvinyl acetal, gasoline-resistant pipe and vinylon synthetic fiber, fabric treatment agent, emulsifier, paper coating, adhesive, etc., widely used in paper making, textile and construction fields.   Industrial chain diagram: