Wire Mesh Performance Terminology

1. Screen

The screen is a woven fabric used as a screen plate support. Vulgar nets, screens, gauze nets, screens, etc.

2. Screen mesh number

The number of meshes refers to the number of meshes per square centimeter (cm2) of wire mesh. The units used to express the number of meshes in the screen product specification are holes/cm or lines/cm. In countries and regions where English units of measure are used, the number of screen meshes is expressed in holes/inch or lines/inch. The number of meshes generally indicates the degree of tightness between silk and silk of the screen. The higher the mesh number is, the denser the mesh is, and the smaller the mesh is. Conversely, the lower the mesh is, the thinner the mesh is, and the larger the mesh is, for example, 150 mesh/inch, that is, there are 150 meshes within 1 inch. The smaller the mesh, the poorer the ink passability and the larger the mesh, the better the ink passability. When selecting the screen, different mesh screens can be selected according to the printing accuracy requirements.

3. Screen thickness

Mesh thickness refers to the distance between the surface of the screen and the bottom surface, typically measured in millimeters (mm) or micrometers (μm). The thickness should be the measured value when the screen is left standing without tension. The thickness is determined by the diameter of the screen, and the amount of ink on the screen is related to the thickness.

4. The opening of the screen

The opening of the screen is an important parameter used to describe the width, aperture, and mesh size of the screen. The opening degree of the screen has a great influence on the fineness of the screen print and the text. The opening actually represents the width of the mesh, expressed as the square root of the area of ​​the mesh enclosed by the two lines of latitude and longitude of the mesh (usually in microns, 1 micron = 1/1000 mm). Therefore, the longer the length of one side of the mesh is, the larger the degree of opening is. However, the same degree of opening, due to the different materials and methods of woven into the screen, the printing effect is also good or bad.

The opening can be calculated as:

O=A1/2(ab)1/2

Where: O - opening (μm);

A—net area;

a, b—the width of the adjacent sides of the mesh;

L - the unit length of the silk screen mesh, 1 cm in metric units, 1 inch in British units, 1 inch = 2.54 cm;

M—the number of screen meshes;

T—the wire diameter of the wire mesh.

5. Screen opening rate

The screen opening rate is also called the screen through hole rate, the effective screen area, the mesh area percentage, etc., that is, the percentage of the mesh area within the screen area per unit area. According to Figure 2-1, the aperture ratio can be calculated as:

Opening ratio = (a × b) / (C × D) × 100% = [SX (] a × b [] (a + T) (b + T) [SX)] × 100%

In the formula: a×b—mesh area;

C × D — screen area;

T—the wire diameter of the wire mesh.

Or opening ratio =

In the formula: O—mesh opening (hole width);

M—the number of screen meshes;

L—The unit length (cm or inch) of the screen mesh is calculated and converted to metric units.

6. The amount of ink in the screen

In actual printing, the amount of ink passing through the screen is affected by the material, properties, specifications of the screen, the viscosity of the ink, pigments and other components, the type of the substrate, the hardness, pressure, and speed of the squeegee, and the plate and the substrate. There are no definite criteria for gaps and other conditions. The hypothetical one through volume is generally called the ink volume.

7. Screen performance terms

(1) Density. Also known as screen density, fabric density. That is, the number of filaments (lines) in the lengthwise direction and the latitudinal unit length of the screen, and the number of warp filaments per unit length in the latitude direction is the warp density, and the number of weft filaments in the unit length along the warp direction is the weft density. . When the warp density of the screen is equal to the weft density, the screen density is equal to the mesh number stated in the screen specification.

(2) Breaking strength. Screen specimens (generally 20 cm in length and 5 cm in width) resist the maximum force at breakage in a tensile test and can be represented by gf (gram force), kgf (kilogram force), N (Newton), and the like.

(3) Elongation at break. The web sample was stretched to the elongation at the time of maximum load breaking.

(4) Elongation at break. The percentage of elongation of the wire sample before the sample is stretched.

(5) Elasticity. The screen is deformed by external forces. After the external force is removed, the deformation disappears and the original form performance can be restored.

(6) Resilience. The screen is deformed by external forces, and the external force is removed. The performance of the original form can be restored after a considerable time.

(7) Antistatic properties. The screen resists the generation or accumulation of static electricity.

(8) Wear resistance. The mesh is resistant to external wear. It is generally expressed as the number of times that the sample is repeatedly worn out by grinding, or as the degree of change in appearance, strength, thickness, weight, etc., after a certain number of grindings.

In the description of screen performance, the terms often used include water resistance, shrinkage, chemical resistance, aging resistance, and the like. In screen printing and plate making, these properties are generally described qualitatively; when quantitative descriptions are required, values ​​should be obtained through tests.

World class Writing Instruments manufacturer & supplier with more than 10 years experience in the industry. Such us Stick Ball Pens, Metal Pen, Plastic retractable ball pens, Twistable Ball Pens, Gel Pen .

Writing Instruments

Writing Instrument, Writing Instruments Pens, Unique Writing Instruments

JNY International Trade Co., Ltd , http://www.jny-stationery.com

Posted on