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Card stock
View on Wikipediafrom Wikipedia
Card stock, also called cover stock and pasteboard, is paper that is thicker and more durable than normal writing and printing paper, but thinner and more flexible than other forms of paperboard.
Use
[edit]Card stock is often used for business cards, postcards, folders, playing cards, scrapbooking, and other applications requiring more durability than regular paper gives.[1][2][3] The surface usually is smooth; it may be textured, metallic, or glossy. Common surface finishes include wove (smooth), laid (parallel ribbing produced by a dandy roll), felt (a textured surface), and embossed patterns such as cordwain and linen.[4][5][6][7] When card stock is labeled cover stock, it often has a glossy coating on one or both sides (C1S or C2S, for "coated: one side" or "coated: two sides"); this is used especially in business cards and book covers.[8]
Measurements
[edit]The weight of cardstock ranges from 50# to 110# (about 135 to 300 g/m2).[a][9]
The length and width of card stock often are stated in terms of the ISO system of paper sizes, in which specific dimensions are implied by numbers prefixed with the letter A. Card stock labeled A3, for example, measures 420 × 297 mm (16.5 × 11.7 in).[b][10][11]
See also
[edit]Notes
[edit]- ^ Most nations describe paper in terms of grammage—the weight in grams of one sheet of the paper measuring one square meter.
Other people, especially in the United States, describe paper in terms of pound weight—the weight in pounds per ream (500 sheets) of the paper with a given area (based on historical production sizes before trimming). For card stock, this is 20 by 26 in (508 by 660 mm); as compared to newsprint (thinner paper) of 24 by 36 in (610 by 914 mm). In describing paper, the pound is often symbolized by the pound symbol, #. Because of the difference in the way pound weight is determined, a sheet of 65# card stock is thicker and heavier than a sheet of 80# newsprint. - ^ Rather than as a function of weight per sheet of a given area, paper thickness can be measured and stated directly, in units of linear measure. In the United States, this usually is expressed in thousandths of an inch, often abbreviated thou points (pt. and pts.) and mils. For example, a 10 pt. card is 0.010 in (0.254 mm) thick (corresponding to a weight of about 250 g/m2), and 12 pt. is 0.012 in (0.3048 mm). The thou point (1/1,000 inch) differs from the typographical point (1/12 traditional pica = exactly 0.01383 inch = 0.35136 mm).
References
[edit]- ^ "Cardstock definition and meaning". Collins English Dictionary. HarperCollins Publishers. Retrieved 23 January 2026.
Paper stock stiff enough for the printing of business cards and similar uses.
- ^ "State Document and Mailing Standards". Washington State Department of Enterprise Services. Washington State Department of Enterprise Services. Retrieved 2026-01-23.
Recommended paper weights: Postcards: 75 lb cardstock, non-glossy.
- ^ Library of Congress Preservation Directorate (30 September 2016). Specifications for File Folders with Reinforced Tab for the Storage of Artifacts (Specification Number 200-211 – 16) (PDF) (Report). Library of Congress. §3.4 "Thickness". Archived (PDF) from the original on 26 February 2025. Retrieved 23 January 2026.
folders should be constructed of 10 pt card stock.
- ^ "Papermaking: Formation of paper sheet by machines". Encyclopædia Britannica. Retrieved 2026-01-23.
- ^ "Glossary of Papermaking Terms". British Association of Paper Historians. Retrieved 2026-01-23.
- ^ "Surface Texture". Hand Papermaking. 2021-03-20. Retrieved 2026-01-23.
- ^ Wheelwright, William Bond (1920). From Paper-mill to Pressroom. George Banta Publishing Company. Retrieved 2026-01-23.
- ^ "Paper Weight, Paper Size, Coated Paper, Matte Paper". Printing Industry Exchange, LLC. Nov 2004. Archived from the original on 2023-06-01. Retrieved 2013-04-04.
- ^ "Paper and Card Stock Comparison Chart" (PDF). The Paper Mill Store. 1 March 2018. Archived from the original (PDF) on 18 April 2016. Retrieved 1 March 2018.
- ^ "Paper Sizes". Archived from the original on 2016-10-29. Retrieved 2013-04-04.
- ^ "Understanding Card Stock Weights". Archived from the original on 2020-11-11. Retrieved 2020-11-11.
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Card stock
View on Grokipediafrom Grokipedia
Card stock, also known as cardstock or cover stock, is a thick, durable paper that is heavier and sturdier than standard writing or printing paper but thinner and more flexible than cardboard.[1][2] It has become a staple for creative and professional applications through modern papermaking innovations.
Card stock varies significantly in weight depending on its intended use. Standard card stock for printing, stationery, and crafting typically weighs between 65 and 110 pounds per ream (approximately 176–300 grams per square meter, based on cover stock basis weight), while heavier weights ranging up to 350–475 gsm or more are commonly used in professional applications such as playing cards, tarot cards, trading cards, and premium packaging.[1][2][3][4] This provides resistance to creasing, tearing, and warping, making it suitable for handling, folding, and gluing. Available in thicknesses ranging from about 10 to 20 points, it provides a professional finish and versatility for various inks, paints, and markers without buckling.[1][2]
Card stock comes in diverse types, including variations by weight (e.g., 80-pound standard), finish (matte, glossy, linen, or textured), and color, as well as specialty options like glitter, iridescent, or gradient surfaces.[1][2] Common sizes include 8.5x11 inches for printing and 12x12 inches for crafting, with sustainable options often made from recyclable or recycled materials.[1]
Its primary uses span creative projects such as greeting cards, business cards, scrapbooking, and invitations; fine art printing like photography and watercolors; archival documents; paper crafts including origami and 3D models; and home decor elements like tags and gift boxes.[1][2] This versatility has made it essential in both DIY hobbies and commercial printing, enhancing durability and aesthetic appeal across applications.[1]
These values establish baseline scales, though actual measurements may vary slightly by manufacturer.[30] Higher weights and thicknesses generally correlate with increased durability, influencing resistance to bending and wear.[28]
Specialty card stock often incorporates colored cores to achieve desired opacity, edge appearance, and light transmission properties. Common core types include white core (standard, natural appearance), black core (for high opacity, prevention of show-through, and black edges when cut, popular in playing cards and tarot decks), blue core, and grey core (for varying aesthetic or functional effects).
Material categories for card stock include white art card (coated paperboard for high print quality), black core card, specialty textured papers, synthetic or plastic card stock (for durability, water resistance, or longevity), and laminated composite stock (multi-layered for added thickness and strength).
For premium applications, ultra-thick duplexed or triplexed card stock is produced by layering multiple sheets, typically two for duplexed (around 28-42 pt) or three for triplexed (32-63 pt), often using cotton-based or premium uncoated materials to achieve substantial heft while maintaining a soft texture. These constructions provide an impressive luxury feel, serving as an elevated upgrade from standard finishes like linen, and frequently incorporate colored or foiled edges for enhanced visual appeal.[31][32][33]
Card stock falls under cover weight paper, which is distinguished from thinner text weight paper by its greater thickness and rigidity. Text weight paper, typically ranging from 60 to 100 lb, is used for applications requiring flexibility, such as 60–70 lb for copier paper and flyers, 80 lb for brochure interiors, and 100 lb for heavy book pages. In contrast, cover weight paper suits sturdier uses, including 65 lb for light greeting cards, 80 lb for postcards and scrapbooking, and 100 lb for business cards and sturdy covers.[28]
Introduction
Definition
Card stock is a type of thick, durable paper valued for its strength and versatility in printing and creative projects. Also known as cover stock or pasteboard, it serves as a robust alternative to standard paper substrates.[5][6] It differs from regular paper, which is thinner and less resistant to wear, offering instead a sturdier structure suitable for handling without easy tearing or creasing. Card stock is also generally thinner and more flexible than paperboard, the latter being a denser material often used in rigid packaging. This positions card stock as an intermediate option, providing sufficient rigidity for standalone items while allowing for bending and scoring.[5][6] Typical thicknesses for card stock fall between 0.010 and 0.020 inches (0.25 to 0.51 mm), or 10 to 20 points, enabling it to maintain flexibility alongside enhanced durability. In the United Kingdom and some other regions, the term "card" is commonly used interchangeably.[7][8]Key Characteristics
Card stock exhibits notable durability and rigidity primarily due to its construction from densely packed fibers, which provide greater resistance to bending and tearing compared to standard paper.[9] This enhanced structural integrity stems from the higher concentration of wood pulp fibers during manufacturing, resulting in a material that maintains shape under stress and withstands repeated handling.[1] The surface of card stock can vary widely to suit different aesthetic and functional needs, including smooth finishes for clean printing, textured options like linen or felt for tactile appeal, matte for a subdued look, glossy for vibrant sheen, metallic for reflective effects, and patterned or embossed designs for decorative purposes.[10] These variations are achieved through coatings, pressing techniques, or specialized processing, influencing how light interacts with the surface and enhancing visual or sensory qualities.[11] Color options for card stock extend beyond basic white to include a spectrum of solid colors and specialty finishes such as pearlescent, which imparts a subtle shimmer.[11] White variants provide a neutral base for accurate color reproduction, while colored and pearlescent types add vibrancy or elegance directly into the material.[10] Environmental factors like moisture absorption and grain direction significantly impact card stock's performance, particularly in terms of foldability and stability. Uncoated surfaces tend to absorb moisture more readily, potentially leading to warping, whereas coated finishes offer better resistance.[11] Grain direction, determined by the alignment of fibers during production, affects rigidity and ease of folding; folding against the grain can cause cracking, while with the grain allows smoother bends.[12] These properties influence applications such as printing, where proper grain orientation ensures clean results.[13]Manufacturing
Raw Materials
Card stock is primarily produced from wood pulp, which consists of a blend of fibers derived from hardwood and softwood trees to balance smoothness, strength, and printability. Hardwood fibers, such as those from eucalyptus, contribute to a smoother surface ideal for high-quality printing, while softwood fibers from trees like pine provide enhanced tensile strength and durability.[14][15][16] Various fillers and additives are incorporated into the pulp to improve specific properties of the final product. Calcium carbonate serves as a key filler, enhancing opacity and brightness while reducing costs by partially replacing more expensive fibers. Starches are added to increase stiffness and surface strength, aiding in the card stock's rigidity for applications like folding and cutting. Dyes are used to achieve desired colors, ensuring uniformity and vibrancy in colored variants.[17][18] Eco-friendly variants of card stock often incorporate recycled content, with some products utilizing up to 100% post-consumer waste to minimize environmental impact and promote resource conservation.[19][20] The sourcing of raw materials emphasizes sustainable forestry practices, where fibers are obtained from responsibly managed forests certified by third-party organizations to ensure long-term ecological balance. Chemical treatments, such as bleaching agents, are applied to whiten the pulp, with modern processes favoring chlorine-free methods to reduce water pollution and preserve forest health.[21][22][23]Production Process
The production of card stock begins with pulping, where raw cellulosic fibers are broken down into a slurry suitable for sheet formation. Mechanical pulping involves grinding debarked wood logs against revolving grindstones or steam-heated rotating steel disks to mechanically separate fibers, retaining lignin for a higher yield (up to 90-95%) but resulting in weaker, darker pulp often used in lower-grade stocks. In contrast, the chemical kraft process cooks wood chips in a digester with a solution of sodium hydroxide and sodium sulfide under heat and pressure, dissolving lignin and hemicellulose to yield a stronger, purer pulp with about 45-50% yield, ideal for durable card stock.[24] Next, the pulp slurry—typically 99% water and 1% fiber—is fed onto a Fourdrinier paper machine, a continuous wire mesh screen moving at speeds of 1,200 to 5,000 feet per minute, where excess water drains through vacuum boxes to form a thin, wet fiber web. This web then passes through a press section, where it is squeezed between felts and rollers under pressure, reducing water content to 40-50% and consolidating the fibers into a cohesive mat.[24][25] The pressed web enters the drying section, passing over a series of steam-heated cylindrical drums at around 200°F to evaporate remaining moisture down to 4-5%, creating a stable sheet. Finishing follows, with the sheet fed through calender stacks—multiple pairs of polished steel rollers—that compress it to precise thickness and impart smoothness via friction and heat. For glossy or specialty finishes, the sheet may undergo coating with pigments like clay or calcium carbonate applied via blade or roll methods, followed by supercalendering for enhanced surface quality.[24][25] Quality control permeates the process, with inline testing for uniformity using tools like micrometers for thickness, tensile testers for strength, and smoothness gauges (e.g., Sheffield testers) to ensure consistency across the sheet. Variations for specialty card stock, such as laminated types, incorporate an additional bonding step where dispersion adhesives are applied to one surface (e.g., flute tips or carrier layers), followed by precise alignment and high-pressure pressing against another substrate like printed paper or board to create multi-layered composites with improved durability and flatness.[24][26]Specifications
Weight and Thickness Measurements
Card stock's weight and thickness are key quantitative measures that determine its suitability for various applications, with grammage providing a universal metric for density. Grammage, or basis weight in the metric system, is defined as the mass of paper per unit area, measured in grams per square meter (gsm) according to ISO 536 standards.[27] For card stock, typical grammage ranges from 176 to 300 gsm for general applications such as stationery, business cards, brochures, and packaging, where lower values offer flexibility and higher values provide rigidity.[28] In commercial and specialty production, particularly for playing cards, tarot cards, trading cards, board games, and premium packaging, heavier grammages are commonly used, often ranging from 250 gsm to 475 gsm or higher, to achieve enhanced durability, stiffness, and premium feel. These higher weights support demanding applications requiring resistance to wear, repeated handling, or structural integrity. In the United States, basis weight for cover stocks like card stock is expressed in pounds (lb) per 500 sheets of a standard size measuring 20 x 26 inches, allowing comparison within paper categories. Common basis weights for typical card stock fall between 65 and 110 lb cover, corresponding to lighter options around 65 lb for everyday printing and heavier ones up to 110 lb for durable constructs.[29] Specialty applications may exceed these ranges. This system reflects the paper's heft without directly indicating thickness, as density variations can influence the relationship.[28] Thickness, often called caliper, is measured in points (pt) or mils (thousandths of an inch), where 1 pt equals 0.001 inch, providing a direct gauge of dimensional depth. Card stock thicknesses typically span 8 to 20 pt (0.008 to 0.020 inches) for standard uses, with thinner stocks around 8-10 pt suiting foldable designs and thicker ones above 15 pt enhancing structural integrity.[28] Conversions between these metrics are approximate due to factors like fiber composition and coatings, but a general rule holds that 10 pt equates to about 250 gsm.[30] Higher grammages in specialty production correspond to greater thicknesses, often exceeding 20 pt. The following table illustrates representative conversions for common card stock specifications, highlighting equivalences across systems:| Basis Weight (lb cover) | Grammage (gsm) | Thickness (pt) |
|---|---|---|
| 65 | 176 | 8 |
| 80 | 216 | 9-10 |
| 100 | 271 | 12 |
| 110 | 298 | 13-14 |
Standard Sizes and Finishes
Card stock is available in a variety of standard sizes that align with international and regional paper formats, facilitating compatibility with printing and cutting equipment. The ISO 216 standard defines the A-series sizes, which are widely used globally for card stock; for instance, A4 measures 210 mm by 297 mm (8.27 inches by 11.69 inches) and is common for documents and cards in Europe and many other regions.[34][35] In North America, the predominant format is US Letter at 8.5 inches by 11 inches, often employed for similar purposes.[36] Regional variations exist to accommodate different markets and equipment, with larger parent sheets—such as 24 inches by 36 inches or 28 inches by 40 inches—produced for industrial applications like packaging and signage, which are then trimmed to smaller standards.[37] Custom cuts are also standard for specific formats, such as 3.5 inches by 2 inches for business cards or 5 inches by 7 inches for invitations, allowing precise adaptation to project needs.[38] Surface finishes for card stock influence print quality, ink absorption, and usability, with three primary types: C1S (coated one side), which provides a glossy finish on the front for printing while leaving the back uncoated for writing or labeling; C2S (coated both sides), offering smooth, high-gloss surfaces on both for double-sided printing; and uncoated, which features a matte, textured surface ideal for handwriting or offset printing without shine.[39][40] In specialty applications such as playing cards, additional textured finishes like linen or air cushion may be applied to improve handling and prevent slipping during use. Post-production processes like cutting and scoring ensure card stock can be shaped and folded accurately. Die-cutting uses sharpened steel rules to create custom shapes beyond straight edges, enabling intricate designs in cards and packaging.[41] Scoring involves pressing a blunt rule into the surface to form a crease for clean folding, preventing cracks especially in thicker stocks; these techniques are compatible with standard sizes and finishes, though adjustments may be needed based on material thickness.[41]Applications
Printing and Stationery
Card stock, which typically refers to cover weight paper, is distinguished from text weight paper by its greater thickness and rigidity, making it suitable for applications requiring durability. Text weight paper, being thinner and more flexible, is commonly used for 60–70 lb stocks in copier paper and flyers, 80 lb for brochure interiors, and 100 lb for heavy book pages. In contrast, cover weight paper includes 65 lb for light greeting cards, 80 lb for postcards and scrapbooking, and 100 lb for business cards and sturdy covers.[42][43][44] Card stock plays a pivotal role in professional printing and stationery applications, where its durability and print quality make it ideal for items that require frequent handling or mailing. In business card production, weights ranging from 80 to 110 lb cover stock are standard to ensure longevity and a premium feel, often utilizing glossy coated two-sides (C2S) finishes to enhance color vibrancy and resistance to wear.[28][45] For postcards and invitations, lighter card stock in the 65 to 80 lb range provides sufficient stiffness for mailing while allowing for perforations or folds without excessive bulk, facilitating cost-effective direct mail campaigns and event correspondence.[7] These weights balance portability and structural integrity, commonly paired with matte or semi-gloss coatings to optimize ink adhesion during production.[46] Heavier card stock exceeding 100 lb is preferred for catalog covers and menus, offering the necessary rigidity to withstand repeated use in retail or dining settings while protecting inner pages.[47] This thickness prevents curling or bending under stress, making it suitable for high-traffic environments.[48] Printing techniques for card stock vary by volume and finish, with offset lithography excelling for large runs due to its ability to handle high pressures on thicker substrates, and digital printing suiting short runs for quick turnaround.[49] Coated surfaces, such as C2S, absorb less ink to produce sharper, more saturated colors, whereas uncoated stocks allow greater ink penetration for a textured, natural appearance but may require adjustments to avoid bleeding.[50] Finishes like gloss or matte, as detailed in standard specifications, further tailor card stock to these printing methods for optimal results.[46] Specialized professional applications, such as playing cards, tarot decks, trading cards, board game components, and premium packaging inserts, often utilize heavier and specialty card stocks ranging from 250 gsm to 475 gsm or higher. These stocks provide enhanced durability for frequent handling and shuffling. Common core types include black core (for high opacity and black edge appearance when cut), blue core, grey core, and white core, with black core particularly favored in high-end playing cards and tarot decks to prevent show-through and offer a premium aesthetic. Such stocks are frequently laminated or coated to improve resilience, shuffleability, and longevity.[4][51]Crafts and Packaging
Card stock plays a prominent role in creative hobbies, particularly scrapbooking and greeting card making, where its varied textures and finishes allow for enhanced visual and tactile appeal. Unlike thinner text weight papers, such as 60–70 lb used for copier paper and flyers or 80 lb for brochure interiors and 100 lb for heavy book pages, cover weight card stock provides the necessary durability; for example, 80 lb is commonly used for scrapbooking to handle embellishments, while 65 lb suits light greeting cards for foldability. Textured varieties, such as linen or fiber, add depth to scrapbook pages by complementing photos, journaling, and embellishments, while also providing durability for long-term preservation of memories.[52][42][53] Metallic or specialty card stocks are favored for greeting cards to create festive or elegant designs suitable for holidays and celebrations, often in weights ranging from 65 to 80 lb to ensure foldability without excessive bulk.[54][55] In the production of playing cards and board game components, card stock's robustness is essential for repeated handling, typically utilizing weights of 250 gsm or higher to prevent wear and maintain structural integrity. Lamination or coatings are commonly applied to these stocks, such as 300 gsm art paper or 310 gsm black core, to enhance resilience against bending and shuffling while preserving print quality.[51][56] Card stock also finds utility in packaging as inserts, dividers, and point-of-sale displays, where its rigidity supports product organization and presentation without adding unnecessary weight. Recycled card stock options, derived from post-consumer fibers, are increasingly adopted for these applications to promote sustainability, as they are fully recyclable and reduce environmental impact compared to virgin materials.[57][58] For do-it-yourself crafts, card stock serves as a versatile base material for techniques like die-cutting, which precisely forms intricate shapes for decorations or models, and embossing, which imparts raised textures for added dimension in projects such as ornaments or custom invitations. These methods leverage the stock's inherent durability to withstand cutting pressures and heat-based embossing without tearing.[54]Historical Development
Origins in Papermaking
The origins of card stock can be traced to early innovations in papermaking that produced thicker, more durable sheets beyond standard writing material. In ancient Egypt, around 3000 BCE, papyrus emerged as one of the first thick, paper-like writing surfaces, crafted from the pith of the Cyperus papyrus plant by slicing, pressing, and drying the strips into sheets that were notably denser than later true paper. These sheets, often several layers thick, served practical purposes requiring rigidity, foreshadowing card stock's role in durable applications. Meanwhile, true papermaking began in China during the 2nd century CE, credited to Cai Lun in 105 CE, who refined the process using rags, hemp, and mulberry bark to create sheets by beating fibers into a pulp, forming them on screens, and drying.[59] Early Chinese papers varied in thickness, with denser variants produced by adjusting fiber concentration for uses like protective wraps, laying the groundwork for thicker stock.[60] By the medieval period in Europe, papermaking evolved alongside traditional materials like vellum, an animal-skin parchment prized for its durability as a writing surface since the 4th century CE. Paper arrived via Islamic traders, with the first European mill established in Xàtiva, Spain, around 1150 CE, producing rag-based sheets that gradually supplemented vellum.[60] By the 13th century, Italian papermakers in Fabriano developed water-powered mills and sized papers for greater strength, enabling thicker sheets for bookbinding covers as early as the 14th century, where multiple layers formed rigid "pasteboards" for limp bindings.[61] These innovations marked a shift toward paper alternatives to vellum, enhancing accessibility for protective and structural uses in manuscripts. In the pre-industrial era, artisans manually produced thicker paper sheets through labor-intensive beating and layering techniques, often for specialized items like playing cards and formal invitations. Handmade paper from linen rags was pounded in wooden vats to achieve greater density, then pressed and dried into sheets suitable for cutting into cards, as seen in 14th-century European playing card production where sturdier stock prevented warping.[61] For invitations and stationery, 17th- and 18th-century European papermakers created bespoke thick sheets by couching multiple thin layers together, providing a premium feel for social correspondence among nobility. The transition to mass-produced denser papers accelerated in the 19th century with the invention of wood pulp processing. In 1843, German machinist Friedrich Gottlob Keller developed a grinding machine that mechanically reduced wood logs into pulp, patented in 1844, which allowed for cheaper, scalable production of thicker, uniform sheets compared to rag-based methods.[62] This breakthrough enabled the widespread availability of card-like stock, bridging handmade traditions to industrial card stock.[63]Modern Innovations
The shift to wood pulp as a primary raw material in the mid-19th century marked a pivotal innovation in card stock production, enabling the creation of thicker, more affordable stocks compared to traditional rag-based papers. Prior to the 1840s, papermaking relied heavily on scarce and expensive rags, limiting the scale and weight of produced sheets; however, the development of wood pulping techniques, such as groundwood processing, utilized abundant wood fibers to generate stronger, heavier pulps suitable for card stock. This revolution, driven by the rising cost of rags in the United States, reduced production expenses and facilitated mass manufacturing of rigid, multi-ply cards used in printing and packaging.[64] Advancements in machinery further refined card stock processing in the late 19th century, with the 1889 introduction of Oscar Friedheim's rotary card cutting and scoring machine exemplifying precision engineering for high-volume production. Invented by the London-based firm Oscar Friedheim Ltd., established in 1884, this steam- or belt-powered device automated the cutting and creasing of card sheets, achieving outputs of up to 100,000 cards per day and ensuring uniform edges essential for business cards and stationery. Friedheim's innovations extended to related equipment like card punching and cornering machines by the early 1890s, transforming manual labor-intensive processes into efficient industrial operations that supported the growing demand for standardized card stock.[65][66] In the 20th century, chemical pulping methods and surface coatings elevated card stock's durability and aesthetic qualities. The kraft process, invented by German chemist Carl F. Dahl in 1879 and patented in 1884, employed sodium sulfide in alkaline cooking to yield strong, flexible pulp from various wood species, becoming the dominant method for producing paperboard and card stock used in packaging by the early 1900s. Complementing this, pigment and clay coatings—initially developed in the late 19th century but widely refined in the 20th—applied layers of kaolinite or calcium carbonate to card surfaces, enhancing whiteness, smoothness, and ink receptivity for finishes like gloss or matte. These treatments, automated via air-knife coaters by the 1940s, allowed card stock to achieve heavier weights while maintaining print-ready qualities. Additionally, the late 19th century saw the introduction of synthetic dyes, which expanded color options and improved vibrancy for card stock applications.[67][68] Post-1970s environmental regulations spurred innovations in sustainable card stock, particularly through increased recycled content. The 1976 Resource Conservation and Recovery Act in the United States, alongside the broader environmental movement ignited by Earth Day 1970, mandated recycling programs and reduced virgin fiber use, leading paper mills to incorporate post-consumer waste into card production for eco-friendly boards. By the 1990s, this evolved with specialized de-inking and blending techniques, yielding recycled card stock that retained strength comparable to virgin materials while minimizing environmental impact. Concurrently, adaptations for digital printing emerged, with card stock engineered using polymer-enhanced coatings to improve ink adhesion and prevent curling in inkjet and laser systems, enabling short-run, high-quality prints on heavy substrates.[69][70][71]References
- https://commons.wikimedia.org/wiki/File:Art_of_Bookbinding_p239_Oscar_Friedheim.png