Hangzhou First pitched its coextruded EP304(T) series EPE for front-side encapsulation of the multi-cut gapless TOPCon module  
The company also promoted its light conversion film, EP304DC, for additional power gain by converting UV rays into visible sunlight 
Also on display was the company’s 0BB cell-to-cell interconnect film, which is suitable for SWCT, IFC, and glue-based processes 
The global PV module market is pivoting towards high-efficiency cells, such as back-contact (BC), TOPCon+, and HJT, from conventional PERC and TOPCon. However, these architectures, with distinct characteristics, pose new challenges for PV materials, spanning processing, module performance, and weatherability. 
Keeping pace with these evolving needs, Hangzhou First, a well-known PV materials provider, showcased its latest range, focusing on TOPCon and BC modules at SNEC 2026, China. 
For multi-cut gapless TOPCon modules, the company promoted its EP304(T) series co-extruded 3-layered EPE film (EVA-POE-EVA). Unlike conventional laminated encapsulants, the one-stage coextrusion process offers several advantages, including higher adhesion strength, transmittance, and long-term weather resistance. In fact, this film’s water vapor transmission rate (WVTR) can resist moisture ingress while maintaining good adhesion between glass, cell, and ribbon during field operations. Besides, the company branded the product as an ‘ultra-high permeability film’ that facilitates higher light transmission into the active cell area, leading to power gain.  
Hangzhou First uses its CF15 series multi-layered coextruded film as a cushion between overlapping cell edges, thereby increasing the active cell area while minimizing the risk of cell cracking. The company also pitched its double-sided coated PET-based insulation strip, which is placed between string busbars and junction box (JB) terminals, eliminating the risk of short circuits.  
Lastly, for the latest modules with 2 kV system voltage, a few companies have shortened creepage distances relative to IEC standards. This distance is the shortest insulation path between the cell matrix edge and the aluminum frames, which are prone to current leakage. Given the severity of up to 33.3% higher DC voltage from the standard 1.5 kV, the company promoted its butyl sealant for edge sealing between glasses and frames. It is a highly impermeable, non-hardening sealant that provides enhanced insulation against humidity and water ingress into the module. 
On the BC side of things, Hangzhou First offers its front-side light conversion film (LCF), EP304DC, designed to shift the UV component of sunlight into the visible range, resulting in power gain.  
For cell-to-cell interconnection of a zero-busbar (0BB) BC module, the company displayed its CF15 film (briefly discussed above), which is classified by width specifications. One matches the module width, while the other equals the cell width. Unlike the normal solder-based interconnection, there are 3 routes for 0BB interconnection. These are carrier film-based Smart Wire Connect Technology (SWCT), film for Integrated Film Covering (IFC) technology, and skin film for ECA glue-based processes. In the ECA-based process, the wider film is used as a skin film, whereas the SWCT and IFC solutions use cell-size films as the carrier and cover films, respectively. According to the company, this film has lower grammage (GSM), higher transmittance, strong adhesion, lower fluidity, and heat shrinkage than conventional EVA. During contact formation in the lamination process, the low viscosity of the molten film helps keep the contact gaps between the fingers and ribbons uncovered, resulting in high-quality electrical contacts. 
In parallel, the positive and negative busbars should be alternatively isolated from the fingers on the rear side of a cell. The company showcased its isolating adhesive ink for this application. In addition, its protective tapes help maintain uniform cell-to-cell gaps during lamination, thereby improving BC module yield. 
TaiyangNews 2024

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