أنواع وأحجام الورق

Paper Types and Sizes

• Several types of paper exist, differing in coating, which affects finish and printability.
• Paper types include uncoated, matte, gloss, and UV gloss, with varying percentages of coating.
• Paper grades are categorized by cost and brand name, or by similar types based on the pulp used.
• Groundwood paper is made from wood pulp, while recycled paper comes from reprocessed fibers.
• Paper quality is impacted by chemical treatments and pulp purity (pH levels of chemicals).
• Common paper types include newspaper, printing paper, and packaging paper.

Paper Production

• Paper production involves several stages, starting with sourcing raw materials.
• Raw materials like wood, cotton, recycled paper, and plant fibers (like bamboo) are used.
• Initial stages include removing impurities, bleaching, and cooking the pulp.
• Paper is formed through a mechanical or chemical process
• Post-processing includes surface finishing, like coating, polishing, or waxing.
• Recycled paper is a significant portion of the process, saving resources.

Paper Manufacturing Processes

• Paper manufacturing processes include mechanical and chemical pulping.
• The mechanical process uses the grinding method, while the chemical method involves using chemicals to separate fibers.
• Cleaning and bleaching are also part of the process.
• Paper is produced mechanically or chemically as either uncoated or coated.
• Depending on the method used, paper takes on varied properties like smoothness and absorbency.

Paper Mounting and Printing

• Paper mounting involves preparing the paper for printing by aligning and placing it correctly on the printing press.
• Printing depends on the type of paper, as some are more suitable for particular types of printing.
• Bleed is the extra space added to designs and images to prevent color or image loss after the trim process.
• Registration marks ensure alignment and accuracy during the printing process.

International Paper Sizes

• International paper sizes are standardized by the International Organization for Standardization (ISO).
• The A series, B series, and C series are standardized for different printing purposes.
• These standard sizing are used for printed materials such as brochures, books, posters, and more.
• Dimensions of paper sizes within each group are standardized.
• These standards allow for consistent paper sizes around the world.

Paper Bleading

• Bleaching is a significant step in paper production, improving the whiteness and brightness of the paper.
• Bleaching processes use chemicals to remove discolorations, like lignin, from raw materials such as wood pulp.
• The process ensures optimal whiteness levels for various printing applications.
• Different types of bleaching methods (mechanical or chemical) have effects on the final paper properties (e.g., absorbency, brightness).

Paper Sizing

• Various paper sizes exist for different printing needs (e.g., A0, A1, A2, A3), with the most frequently used being A4.
• Sizes are standardized for consistent results and reduced waste in printing.
• Paper sizes and their corresponding dimensions are standardized for efficient use and minimal wastage.

Other Printing Terms

• Mounting involves placing the design onto the page with appropriate margins.
• Folding involves creating folds or creases in the paper, often for booklets or brochures.
• Trimming removes excess paper around the edges of the printed material.
• Bleed refers to an area beyond the actual image or text that is printed to prevent white edges.
• Registration marks assist in aligning multiple colors or images during printing.
• Gripper is a mechanical device that holds and feeds the paper during printing.
• Color bars allow for color consistency during printing.
• Trim marks on the printed sheet act as a guide during the trimming process.