Reechas lists some of the most commonly encountered PCB laminate problems and how to confirm them here. Once encountering PCB laminate issues, it should be considered to add them to the PCB laminate material specification.

1、 To be able to track and find

It is impossible to manufacture any number of PCBs without encountering some problems, mainly due to the material of PCB copper clad laminates. When quality problems occur in the actual manufacturing process, it seems that the PCB substrate material often becomes the cause of the problem. Even a carefully written and effectively executed technical specification for PCB laminates does not specify the testing items that must be carried out to determine whether PCB laminates are the cause of production process problems. Here are some of the most commonly encountered PCB laminate issues and how to confirm them.

Once encountering PCB laminate issues, it should be considered to add them to the PCB laminate material specification. Usually, if such technical specifications are not enriched, it will result in continuous quality changes and subsequently lead to product scrapping. Usually, material problems caused by changes in the quality of PCB laminates occur in products manufactured by manufacturers using different batches of raw materials or using different pressing loads. Few users can hold a large amount of sufficient records to distinguish specific pressing loads or material batches in the processing site. So it often happens that PCBs are constantly produced and components are installed, and they continuously warp in the solder slot, wasting a lot of labor and expensive components. If the loading batch number is immediately available, the PCB laminate manufacturer can verify the resin batch number, copper foil batch number, curing cycle, etc. That is to say, if users cannot provide continuity with the quality control system of PCB laminate manufacturers, it will result in long-term losses for users themselves. The following introduces general issues related to substrate materials in the PCB manufacturing process.

2、 Surface issues;

 Symptoms: Poor adhesion of printing materials, poor adhesion of coatings, inability to etch off certain parts, and inability to solder certain parts

 Acceptable inspection methods: Usually, visible water marks are formed on the surface of the board for visual inspection:;

 Possible reasons:;

Due to the extremely dense and smooth surface caused by the demolding film, the uncoated copper surface is excessively bright;

Usually, on the uncoated side of the laminate, the laminate manufacturer does not remove the release agent;

 The pinholes on the copper foil cause resin to flow out and accumulate on the surface of the copper foil, which typically occurs on copper foils thinner than 3/4 ounce weight specifications

 Copper foil manufacturers apply excessive amounts of antioxidants to the surface of copper foil

 The manufacturer of the laminate has changed the resin system, demoulding thin, or brushing method

 Due to improper operation, there are many fingerprints or oil stains

 Stain oil during punching, cutting, or drilling operations

 Possible solutions:;

 Before making any changes to the manufacturing of the laminate, cooperate with the laminate manufacturer and specify the user's test items

It is recommended that laminates manufacturers use fabric like films or other demolding materials

 Contact the laminate manufacturer to inspect each batch of copper foil that fails; Request a solution to remove the recommended resin

 Request a method of removal from the laminate manufacturer. Chang Tong recommends using hydrochloric acid, followed by mechanical brushing to remove it

 Contact the laminate manufacturer and use mechanical or chemical elimination methods

 Educate all process personnel to wear gloves and hold copper clad plates. Find out if there is a suitable pad paper or bag for the laminated board during transportation, and if the pad paper has a low sulfur content and the packaging bag is free of dirt. Pay attention to ensuring that no one comes into contact with the copper foil while using detergent containing silicone

 Degrease all laminates before plating or graphic transfer printing process. Reechas is a high-tech enterprise founded in 2006 and headquartered in Shenzhen, China. We focus on the development, production, and sales of integrated laminating products, including release films, conformal films, and press pads. These products are widely usedin PCB, FPC,  rigid-flex PCB, 5G PCB, IC substrate, CCL, smart card, copper coin & heat-sink and other industries.