The grammage of paper refers to how many grams per square meter. So you can cut a 10*10 cm piece of paper, weigh it with an electronic scale, and then divide the weight by the area to convert the gram weight.
Coated paper, also known as coated printing paper, is called powder paper in Hong Kong and other regions. It is a premium printing paper made of base paper coated with white paint. It is mainly used for printing the covers and illustrations of high-level books and periodicals, color pictures, various exquisite commodity advertisements, samples, commodity packaging, trademarks, etc. Generally, if you want rich colors and complex patterns, coated paper is used.
Common classification: Coated paper is divided into single-sided coated paper, double-sided coated paper, matt coated paper, and cloth coated paper. According to the quality is divided into A, B, C three grades.
Common gram weights: The gram weights of coated paper are .70, 80, 105, 128, 157, 180, 200, 230, 250, 300, 400, 450 grams, etc.
Advantages: The color is very bright, the paper is very absorbent, the color reproduction is high, and it is mostly used for photos, landscapes, and some postcards with rich colors. It can be laminated, and it has a better feel after lamination. The original material of the paper is smooth and very textured
Disadvantages: The handwriting should not be dry, because it is too smooth, so what is written with a pen and water pen (gel pen) is easily erased, and the postmark and seal after the modification will also be erased immediately. Compared to the same gram of paper, the hardness is medium, not hard. Inexpensive. In fact, it is the thickened version of the leaflets and advertisements (usually 85-100g) issued on the street (postcards are generally about 300g). It is easy to become curled in the south wind and is not resistant to moisture.
Features: Matte paper, the official name is matte coated paper. Viewed in sunlight, it is less reflective than coated paper. Generally, the matte paper will be thinner and whiter than the copper plate, more ink-absorbing, and more rigid, unlike the coated paper, which is easily deformed.
Common uses: high-end product catalogs, products showing elegant and simple style (such as: instruments, calligraphy and painting, antiques, etc.) or magazines with photos or illustrations, portfolios, etc., do not focus on showing bright effects.
Common gram weight: The gram weight of matte paper is 105, 128, 157, 200, 250, and 300 grams.
Advantages: easy to color. The front is equivalent to cardboard. Inexpensive.
Cons: Very soft. 300g matte paper is as hard as 250g cardboard. Personally, I don’t think it’s suitable for postcards. No cardboard thickness, no coated paper, beautiful color.
Characteristics: Single-layer or multi-layer combined paper made entirely by bleached chemical pulping and fully sizing, generally the basis weight is above 150g/㎡. The characteristics of this cardboard are: high smoothness, good stiffness, neat appearance and good formation.
Common uses: business card printing, certificates, invitations, covers, monthly desk calendars and postcards, etc.
Common weights: white cardboard weights of 200, 250, 300, 350, 400 grams are more commonly used.
Advantages: thick enough and hard enough. The hardness of the cardboard is very high among the paper of the same number of grams. People who like thick cards will really appreciate this paper. The color is as convenient as coated paper, and it is also very colorful. Writing on the reverse side is easily wiped off immediately. The middle price is the best choice for postcard paper selection. Cost-effective, the price is in the middle.
Disadvantages: It is easy to scratch, from printing to writing, daily contact is very easy to scratch the front very ugly, generally high-grade cardboard will be covered with film to prevent scratches. Special black and dark colors will have traces when touched. And irreversible. The south wind is easy to turn into a curl, and it is usually the front that wants to arch up.
Features: “Dowling paper” should be called “offset printing paper” or “offset paper”. Offset printing paper is a relatively advanced book printing paper, which has higher requirements on the ratio, expansion ratio and surface strength during printing. The acidity and alkalinity should also be close to neutral or slightly alkaline.
Common uses: suitable for printing monochromatic or multi-color book covers, text, inserts, pictorials, maps, posters, color trademarks and various packaging products.
Common weights: Dowling paper weights of 70, 80, 100, 120 grams are more commonly used.
Advantages: Dowling paper has small elasticity, uniform ink absorption, good smoothness, tight and opaque texture, good whiteness and strong water resistance.
Features: Pearl paper is composed of three parts: bottom fiber, filler and surface coating. The surface is very smooth, the thickness is thick, the reflection is strong, and it has pearl luster.
Common uses: high-end picture albums, books, exquisite packaging, boxes, greeting cards, hang tags, etc.
Common gram weight: Pearl paper has 120, 250, 280 grams, etc., which are more commonly used.
Advantages: Pearl paper has light specific gravity, good waterproof toughness, no tearing, corrosion resistance, folding resistance, light resistance, no discoloration, unique texture, strong three-dimensional effect, and bright printing.
Disadvantages: The disadvantage is that the color printing effect is average (but pearl paper is used for printing black and white drawings, and the effect is acceptable when encountering a few color parts, so it does not matter much). Another disadvantage is that it is not particularly easy to glue. It needs to be clamped with small tweezers for a while to fix it, but it is still very strong after bonding.
White cardboard is a kind of cardboard with white and smooth front and gray background on the back. This kind of cardboard is mainly used for single-sided color printing and then made into cartons for packaging, or for design and handmade products.
Most of the base paper uses wood pulp, and some straw pulp can also be used. Waxed paper is divided into white and bleached. It can be dyed in different colors according to the needs of the product. Silica (quartz powder) is used as the white pigment, and some high-melting waxes are added. The adhesive is preferably animal glue. After coating, it is repeatedly polished on a grindstone polisher. There are also uncoated papers that are simply rubbed with flint to achieve a waxy finish. It is mostly used for decoration, exquisite packaging and other occasions.
Other special paper
In addition to the above-mentioned conventional papers, some special-purpose papers include, super-sensitive paper, embossed paper, patterned paper, highly calendered paper, painting newspaper, etc.