{"id":2729,"date":"2026-10-04T09:00:00","date_gmt":"2026-10-04T01:00:00","guid":{"rendered":"https:\/\/www.jingpengpcb.com\/?p=2729"},"modified":"2026-09-30T09:27:54","modified_gmt":"2026-09-30T01:27:54","slug":"pcb-foundation-course-part-2","status":"publish","type":"post","link":"https:\/\/www.jingpengpcb.com\/en\/blog\/pcb-foundation-course-part-2\/","title":{"rendered":"How Are Copper-Clad Laminates Manufactured? Types, Classification, and National Standards Requirements"},"content":{"rendered":"<p>Welcome to Chapter 2 of our introductory textbook on printed circuit boards for the new school year. In this chapter, we\u2019ll take an in-depth look at the manufacturing process of copper-clad laminates and the different types available. This knowledge is essential for electronic circuit design and PCB manufacturing. Let\u2019s explore this exciting field together.<br \/>\n<img loading=\"lazy\" decoding=\"async\" width=\"716\" height=\"550\" class=\"alignnone size-large wp-image-7594\" src=\"https:\/\/www.jingpengpcb.com\/wp-content\/uploads\/2023\/09\/product-HDI_pcb.webp\" alt=\"HDI (High-Density Interconnect) Printed Circuit Boards\" srcset=\"https:\/\/www.jingpengpcb.com\/wp-content\/uploads\/2023\/09\/product-HDI_pcb.webp 716w, https:\/\/www.jingpengpcb.com\/wp-content\/uploads\/2023\/09\/product-HDI_pcb-300x230.webp 300w\" sizes=\"auto, (max-width: 716px) 100vw, 716px\" \/><\/p>\n<h2>Table of Contents<\/h2>\n<ol>\n<li>Briefly describe how general copper-clad laminates are manufactured.<\/li>\n<li>Types and Classification of Copper-Clad Laminates<\/li>\n<li>The Significance of National Standard GB\/T 4721-92<\/li>\n<li>Common English Abbreviations and Their Meanings<\/li>\n<li>UL Standards and Quality and Safety Certification Organizations<\/li>\n<li>Methods for Manufacturing Copper Foil and Its Classification<\/li>\n<li>Performance Characteristics of Electrolytic Copper Foil and Rolled Copper Foil<\/li>\n<li>Technical Properties of Electrolytic Copper Foil and<a href=\"\/en\/capabilities\/pcb-materials\/\">Copper-Clad Laminate<\/a>Impact on Performance<\/li>\n<li>Properties of Fiberglass Cloth<\/li>\n<li>Common Types of Paper-Based Copper-Clad Laminates<\/li>\n<li>A Comparison of Paper-Based Copper-Clad Laminates and Epoxy-Glass-Fabric-Based Copper-Clad Laminates<\/li>\n<li>Properties of Phenolic Paper-Based Copper-Clad Laminates<\/li>\n<li>Characteristics of Standard Glass-Fiber-Based Copper-Clad Laminates<\/li>\n<li>Classification and Thickness Ranges of FR-4 Printed Circuit Boards<\/li>\n<li>The Significance and Characteristics of CEM-3 Copper-Clad Laminate<\/li>\n<\/ol>\n<h2>1. Briefly describe how standard copper-clad laminates are manufactured.<\/h2>\n<p>Copper-clad laminates are generally manufactured through the following steps:<\/p>\n<ol>\n<li>Select reinforcing materials, such as fiberglass cloth, fiberglass mat, or impregnated fiber paper.<\/li>\n<li>Impregnated reinforced materials are bonded with resin to form a preform.<\/li>\n<li>The blank is dried and cut to the desired size.<\/li>\n<li>Cover the blank with copper foil.<\/li>\n<li>Using steel plates as dies, the blank is pressed into the desired shape under high temperature and high pressure.<\/li>\n<\/ol>\n<h2>2. Types and Classification of Copper-Clad Laminates<\/h2>\n<p>Copper-clad laminates can be divided into two categories based on their rigidity and the type of reinforcing material used:<\/p>\n<ul>\n<li>Rigid Copper-Clad Laminate: Suitable for rigid printed circuit boards.<\/li>\n<li>Flexible Copper-Clad Laminate: Suitable for flexible printed circuit boards.<\/li>\n<\/ul>\n<p>Depending on the type of reinforcing material used, copper-clad laminates can be divided into four major categories:<\/p>\n<ol>\n<li>Paper-based copper-clad laminate<\/li>\n<li>Copper-Clad Laminate with Glass Fiber Base<\/li>\n<li>Copper-clad laminates with composite substrates, such as the CEM series<\/li>\n<li>Copper-clad laminates with special substrates, such as ceramic or metal substrates.<\/li>\n<\/ol>\n<h2>3. The Significance of National Standard GB\/T 4721-92<\/h2>\n<p>The national standard GB\/T 4721-92 pertains to copper-clad laminates and provides specifications for product designations. In these designations, the first letter, \u201cC,\u201d stands for copper-clad; the next two letters indicate the base material and reinforcing material; and the last two digits denote the product number for items of the same type but with different performance characteristics.<\/p>\n<h2>4. Common English Abbreviations and Their Meanings<\/h2>\n<p>In the printed circuit board industry, there are many common English abbreviations, including:<\/p>\n<ul>\n<li>JIS: Japanese Industrial Standards<\/li>\n<li>ASTM: American Society for Testing and Materials Standards<\/li>\n<li>NEMA: National Electrical Manufacturers Association Standards<\/li>\n<li>MIL: U.S. Military Standard<\/li>\n<li>IPC: Standards of the U.S. Interconnect and Packaging Council<\/li>\n<li>ANSI: American National Standards Institute standards<\/li>\n<li>UL: Underwriters Laboratories Standards<\/li>\n<li>IEC: International Electrotechnical Commission Standards<\/li>\n<li>BS: British Standards Institution standards<\/li>\n<li>DIN: German Institute for Standardization<\/li>\n<li>VDE: German Electrical Standards<\/li>\n<li>CSA: Canadian Standards Association Standards<\/li>\n<li>AS: Australian Standards Association Standards<\/li>\n<\/ul>\n<h2>5. UL Standards and Quality and Safety Certification Bodies<\/h2>\n<p>UL stands for \u201dUnderwriters Laboratories.\u201d UL has published numerous safety standards, including those related to copper-clad laminates. UL certification is a mark of product quality and safety.<\/p>\n<h2>6. Methods for Manufacturing Copper Foil and Its Classification<\/h2>\n<p>Copper foil can be divided into two main categories: rolled copper foil and electrolytic copper foil. In IPC standards, they are referred to as Class W and Class E, respectively. Rolled copper foil is produced through repeated rolling, while electrolytic copper foil is produced through electrolytic refining.<\/p>\n<h2>7. Performance Characteristics of Electrolytic Copper Foil and Rolled Copper Foil<\/h2>\n<p>Electrolytic copper foil typically has greater fold resistance and a higher coefficient of elasticity than rolled copper foil, and it also has a higher copper purity. Electrolytic copper foil is superior to rolled copper foil in terms of surface smoothness. These performance characteristics are critical for the design and manufacture of printed circuit boards.<\/p>\n<h2>8. The Technical Properties of Electrolytic Copper Foil and Their Impact on the Properties of Copper-Clad Laminates<\/h2>\n<p>The technical properties of electrolytic copper foil\u2014such as thickness, appearance, tensile strength, peel strength, flex resistance, surface roughness, etchability, and resistance to high-temperature oxidation\u2014directly affect the performance of copper-clad laminates. Understanding these properties is crucial for selecting the appropriate copper-clad laminate.<\/p>\n<h2>9. Properties of Fiberglass Cloth<\/h2>\n<p>Fiberglass cloth is a commonly used reinforcing material. Its properties include the types of warp and weft yarns, weave density, thickness, weight, width, and tensile strength. These properties affect the quality and performance of copper-clad laminates.<\/p>\n<h2>10. Common Types of Paper-Based Copper-Clad Laminates<\/h2>\n<p>Paper-based copper-clad laminates are commonly used in the manufacture of electronic circuits. Common types include XPC, XXXPC, FR-1 (XPC-FR), FR-2 (XXXPC-FR), FR-3, and others. They are inexpensive and easy to process, but they have high water absorption.<\/p>\n<h2>11. Comparison of Paper-Based Copper-Clad Laminates and Epoxy-Glass-Fabric-Based Copper-Clad Laminates<\/h2>\n<p>Paper-based copper-clad laminates and epoxy-glass-fabric-based copper-clad laminates differ in their performance characteristics. Paper-based laminates are inexpensive and easy to punch, but they are inferior to glass-fabric-based laminates in certain performance aspects, particularly water absorption.<\/p>\n<h2>12. Properties of Phenolic Paper-Based Copper-Clad Laminates<\/h2>\n<p>Phenolic paper-based copper-clad laminates possess a wide range of properties, including dielectric properties, mechanical properties, physical properties, and flame retardancy. In addition, they exhibit several application-specific properties, such as punchability, dimensional stability, water absorption, impact strength, and resistance to solder wicking.<\/p>\n<h2>13. Characteristics of Standard Glass-Fiber-Based Copper-Clad Laminates<\/h2>\n<p>Standard glass-fiber-reinforced copper-clad laminates use Type E glass fiber cloth and typically feature electrolytically roughened copper foil with thicknesses of 0.018 mm, 0.035 mm, and 0.070 mm. These laminates are widely used in electronic products and offer excellent performance and durability.<\/p>\n<h2>14. Classification and Thickness Ranges of FR-4 Circuit Boards<\/h2>\n<p>FR-4 printed circuit boards are divided into two types: rigid printed circuit boards and thin-film core layers used in multilayer printed circuit boards. Their thickness ranges are 0.8\u20133.2 millimeters and 0.1\u20130.75 millimeters, respectively.<\/p>\n<h2>15. The Significance and Characteristics of CEM-3 Copper-Clad Laminate<\/h2>\n<p>The CEM-3 copper-clad laminate uses a non-woven glass fiber fabric, offering improved punch-forming performance, heat resistance, copper foil peel strength, and insulation properties. It is widely used in lightweight, thin, and compact electronic products, meeting a variety of performance requirements.<\/p>\n<h2>Frequently Asked Questions<\/h2>\n<p><strong>Q1: What is UL certification?<\/strong><\/p>\n<p>UL certification is a quality and safety certification that ensures products comply with relevant standards and requirements. In printed circuit board manufacturing, UL certification is an important certification that ensures product quality and safety.<\/p>\n<p><strong>Q2: What is the difference between electrolytic copper foil and rolled copper foil?<\/strong><\/p>\n<p>Electrolytic copper foil is produced through electrolytic refining and features high purity and a smooth surface. Rolled copper foil is produced through mechanical processing and offers high strength and resistance to bending.<\/p>\n<p><strong>Q3: What are the differences between paper-based copper-clad laminates and glass-fiber-based copper-clad laminates?<\/strong><\/p>\n<p>Paper substrates are inexpensive and easy to process, but they are highly absorbent. Glass cloth substrates offer better performance and durability, but they are more expensive.<\/p>\n<h2>Conclusion<\/h2>\n<p>Copper-clad laminates are a key component in the design and manufacturing of electronic circuits. Understanding the different types of copper-clad laminates and their performance characteristics is essential for selecting the right circuit board. If you need further information or have questions about circuit board design, please feel free to contact us. Let\u2019s work together to advance electronic technology!<\/p>\n<p>If you have any questions or would like to learn more about PCB manufacturing, please feel free to contact me\u2014I\u2019ll be happy to assist you.<\/p>\n<p><strong>Additional Information<\/strong>\uff1a<a href=\"\/en\/blog\/performance-of-three-types-of-rigid-copper-clad-laminates\/\">A Comparison of the Properties of the Three Most Common Types of Rigid Copper-Clad Laminates<\/a> \u00b7 <a href=\"\/en\/blog\/circuit-board-compression\/\">Common Issues and Solutions for the Laminating Process of Multilayer Printed Circuit Boards<\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>\u6b22\u8fce\u9605\u8bfb\u5f00\u5b66\u5b63\u7684\u7535\u8def\u677f\u57fa\u7840\u6559\u6750\u7b2c\u4e8c\u7ae0\u3002\u5728\u8fd9\u4e00\u7ae0\u4e2d\uff0c\u6211\u4eec\u5c06\u6df1\u5165\u4e86\u89e3\u8986\u94dc\u7b94\u677f\u7684\u5236\u4f5c\u8fc7\u7a0b\u4ee5\u53ca\u5176\u4e0d\u540c\u7c7b\u578b\u3002\u8fd9\u4e9b\u77e5\u8bc6\u5bf9\u4e8e [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":7594,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"slim_seo":{"title":"How Are Copper-Clad Laminates Manufactured? 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Based on the actual process capabilities of the production line, it explains how to determine the parameters."},"_slim_seo_primary_term_category":0,"_slim_seo_primary_term_post_tag":0,"footnotes":""},"categories":[407,26],"tags":[],"class_list":["post-2729","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-pcb-materials","category-blog"],"_links":{"self":[{"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/posts\/2729","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/comments?post=2729"}],"version-history":[{"count":4,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/posts\/2729\/revisions"}],"predecessor-version":[{"id":18816,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/posts\/2729\/revisions\/18816"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/media\/7594"}],"wp:attachment":[{"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/media?parent=2729"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/categories?post=2729"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.jingpengpcb.com\/en\/wp-json\/wp\/v2\/tags?post=2729"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}