Paper Basic Knowledge Analysis

In a printing plant, one can observe stacks of paper neatly arranged beneath the feed mechanism of the printing press. Upon activation, these sheets are sequentially fed into the machine for printing and subsequently output in the same order, ultimately becoming printed materials such as books, albums, and posters. This single-sheet printing method is extensively utilized in the production of various printed items.

Prior to leaving the factory, sheet paper is meticulously cut to specific dimensions suitable for large-format sheet-fed presses, referred to as "full sheets." Printing plants may further trim these full sheets into smaller formats to accommodate different types of sheet-fed presses. The dimensions of full sheets adhere to standardized specifications within the paper and printing industries. In China, there exist multiple sizes of full sheets, each with its own nomenclature. Commonly used specifications include:

The origins of these standards can be traced back to the printing practices of the Republic of China era. During that time, publications like dictionaries, books, and newspapers were predominantly printed on standard-sized paper. The introduction of international ISO standards, originating from Germany, has gradually become the current standard in China due to its larger size compared to traditional paper, hence the term "generous paper."

Apart from standard and generous paper, three other common sizing systems are widely recognized globally: A, B, and C series. These standards are extensively used in various printers and design software, including familiar sizes such as A4 printer paper and B6 envelopes.

According to national standards, uncut paper produced by manufacturers is termed "full open paper." By dividing this paper into equal sections, different opening numbers are formed. For instance, a full sheet divided into two halves results in "split" paper, while division into four parts yields "four-fold" paper. The commonly encountered "16-open" paper refers to a full sheet equally divided into 16 pieces.

The concept of printing size is crucial in the printing industry, varying based on the intended use. Paper is primarily categorized into flat paper and web paper. Flat paper, characterized by its flat surface and moderate size, is widely employed in general printing presses for items like books and albums. Web paper, due to its elongated shape and suitability for high-speed continuous printing, is typically used in high-speed rotary presses for newspaper printing. National standards define the size of uncut paper as "full paper," with subsequent cutting forming different opening numbers.

For important printed materials such as textbooks and official documents for primary and secondary schools, the state mandates uniform size standards. Currently, China uses standard paper as the baseline for printing 16-open books. If printed on generous paper, it is designated as a large 16-open book to differentiate from the standard size.

These printing size standards are not only applicable to significant prints but also widely utilized in various paper products. Consequently, leaflets and similar items often adopt the 210mm×285mm size, aligning with the standard generous 16-open size. Utilizing 889mm×1194mm generous full sheet paper enhances efficient paper resource utilization and minimizes waste.

Although standard size data is provided, designers retain flexibility in actual practice. However, non-standard sizes can lead to paper waste, so consulting a printing professional before design is advisable to ensure appropriate sizing.

The naming conventions for A, B, and C series paper differ. In the A series, each halving of the size increments the number by 1. For example, "A0" becomes "A1" when halved, "A1" becomes "A2" upon further halving, and so forth. Commonly used sizes in copy paper include A3 to A6:

- A3 dimensions: 297×420 mm
- A4 dimensions: 210×297 mm
- A5 dimensions: 148×210 mm
- A6 dimensions: 105×144 mm

Designers can fine-tune these standard sizes to meet specific needs. However, non-standard sizes can cause paper waste, so consulting a printing professional before design is recommended to ensure the right size selection.

Note: Although the 16-open size (210×285 mm) resembles the A4 size (210×297 mm), selecting A4 during printing is generally discouraged due to its deviation from standard printing sizes, leading to increased costs through paper waste. This is a common oversight among new designers.

Common printing size list:
- Business card: 90×55 mm or 85×54 mm
- Work ID: 85.5×54 mm
- Coupon: 215×95 mm
- Invitation: 140×210 mm
- Membership card: 90×50 mm
- Admission ticket: 200×80 mm
- DM flyer: 210×285 mm
- Handbag: 400×258×80 mm
- X display/roll size: 60×160 cm, 80×180 cm, 120×200 cm, or 80×200 cm.

When selecting paper, careful consideration should be given to customer requirements and design objectives to achieve optimal printing results.