Đo độ bóng là gì , Tại sao phải đo độ bóng

Gloss is determined by shining a beam of light of fixed intensity and angle onto the surface and measuring the amount of light reflected at equal but opposite angles.
There are several different geometries available for gloss measurement, each depending on the type of surface being measured. For non-metallic materials such as coatings and plastics, the amount of reflected light increases with increasing angles of illumination, as some of the light passes through the surface material and is either absorbed into the surface or diffusely scattered from the surface depending on the surface colour. Metals have much higher reflectance and are therefore less dependent on angle.

Why measure gloss?

Product line Gloss Checker SEMIKI's Gloss Checker provides an easy-to-use and objective way to check surface gloss, eliminating the ambiguity of subjective observations. SEMIKI's Gloss Checker product line provides a numerical value for gloss, which can be used in quality control and process benchmarking.

What does gloss value mean?

When light strikes an object, some of it is reflected, refracted, or absorbed. There are basically two ways light reflects off a surface, specular reflection and diffuse reflection. The Horiba gloss tester measures specular reflection. The angle of incidence can be set at two different angles, 20° and 60° (IG-331) to suit different surface conditions. The standard incident angle set for most applications is 60°.

High gloss surface

Specular reflection is a mirror-like reflection in which the angle of incidence is identical to the angle of reflection with respect to the surface normal. . Polished surfaces produce more specular reflection and less diffuse reflection.

Low gloss surface

Diffuse reflection is a fuzzy reflection in which incident light is reflected at many different scattering angles. A frosted glass or cardboard produces less specular reflection and more diffuse reflection. We perceive such a surface as dull or matte.

Example of how to use a gloss meter

HORIBA gloss testers offer instant and highly accurate measurement, and can be applied in many places such as polishing, painting, building cleaning and visual inspection of furniture and building materials.

Choose the correct gloss measurement angle

Gloss measurement is based on the amount of light reflected off a surface compared to a polished standard glass, measured in Gloss Units (GU). The amount of light reflected off a surface depends on the angle of incidence and the nature of the surface.

Gloss is classified as matte, semi-gloss, or high gloss. To determine the best measurement angle, start with the gloss meter set at a 60° angle of incidence.

If the result is between 10 – 70GU, the coating is considered ‘semi-gloss’ and must be measured at a 60° angle on a gloss meter. If the result is less than 10GU, the product is considered “low gloss” and must be measured at an 85° angle on a gloss meter, and if the result is greater than 70GU, the product is considered “high gloss” and must be measured at a 20° angle on a gloss meter.

All three angles should be recorded (20, 60 and 85°) when measuring gloss on anodized metal to ensure a clear understanding of the specular reflectance between the coating and the metal substrate.

Gloss range	60° value	Measured by
High gloss	> 70GU	20°
Sell ball	10 – 70GU	60°
Low/Dim	< 10GU	85°

% Reflex

Although the Gloss Unit (GU) scale is linear, each angle of incidence has a different measurement range; 0 – 2000GU (20°), 0 – 1000GU (60°), 0 – 160GU (85°).

% Reflectance compares the amount of light energy transmitted and received by the gloss meter and expresses the value as a percentage of the full incident angle measurement range and the value is displayed as a percentage relative to the selected incident angle.

Vì phạm vi đo của máy đo độ bóng 20° là 0 -2000GU; giá trị 1000GU ở 20° sẽ được biểu thị là 50%20 và giá trị 500GU sẽ được biểu thị là 25%20. Giá trị 500GU ở 60°, nhưng sẽ được biểu thị là 50%60 vì phạm vi đo cho 60° là 0 – 1000GU. Bề mặt càng sáng bóng thì giá trị sẽ càng gần 100%.

Materials with high refractive indices such as clear plastics or varnishes can have values above 100GU. Highly reflective metals can have gloss values up to 2000GU. Furthermore, the measurement value can increase for transparent materials due to the large amount of reflection in the bulk of the material. In all these cases, it is common to express the measurement result as % Reflectance.

Car wash, polish, paint

To test the effectiveness and degradation of car body coatings and waxes.
Useful as a sales tool to convince customers to repaint when the current coating is degraded.
To check the uniformity of gloss when painting a part or repairing an automobile
Numeric values can be used to determine whether the repaired area is as shiny as the surrounding area.

Building cleaning and maintenance

To control aesthetics in maintenance
Shiny floors in stores make a good impression on customers
To check the floor polishing efficiency and report the work to the customer.
Recording and reporting numerical values makes the report more convincing.

Cleaning solar panels

To quantify the dirtiness of solar panels
Determining optimal cleaning times helps reduce cleaning costs
To check the efficiency after cleaning the solar panels and report the work to the customer.
Recording and reporting numerical values makes the report more convincing.

Check the appearance of the furniture

Used to check the appearance of wood products such as furniture and musical instruments.
Useful for visual inspection of various products, such as wood grain surfaces, painted or coated surfaces, etc.
To check the gloss at each step of the process, such as surface preparation, priming, finishing, etc.
Helps standardize optimal work in each process

Visual inspection of construction materials

To check the appearance of exterior walls, floor slabs and other panels and window frames
Helps confirm overall uniform gloss
To test the weather resistance of building materials
To check for surface degradation due to aging and UV

Check the finishing of the stone polishing

To check the finishing state in each process from rough to mirror finish
Helps standardize optimal work in each process
To check the effectiveness of headstone and other stone maintenance activities
Recording and reporting numerical values makes the report more convincing.

Confirm cleaning performance

To test the performance of the washing machine and detergent
Helps to benchmark performance during research and development
To test the effectiveness of anti-fouling materials and anti-fouling coatings
Not only useful for performance evaluation but also for checking degradation

Check the appearance of printed documents

To check the gloss of printing materials and printing paper
To evaluate the aesthetic performance of glossy printing materials such as coatings and finishes

Check the appearance of the plastic

For visual inspection of plastic molded and processed products
Check for surface degradation due to aging and UV, and evaluate during weathering testing

Please contact SEMIKI to have the most suitable product gloss measurement solutions from Japan.
CONTACT:
SEMIKI Measuring Equipment Company Limited
Email: [email protected]
Phone: +84 9797 61016