Automatic Drying Time Tester NIP-DTR6800 - Applications:

The Automatic Drying Time Tester NIP-DTR6800 It is used for the standardized determination of the drying time of organic coatings according to ASTM D5895 and ISO 9117-4. These internationally recognized test methods define how the transition of a coating film from the liquid state to complete curing is measured using a mechanical linear recorder The NIP-DTR6800 offers a precise feed rate, stable load application, and a multi-sample platform, enabling the reliable determination of reproducible and precisely defined drying stages for R&D laboratories, paint manufacturers, and industrial quality control.

General explanation regarding drying time testing

The Drying Test serves to determine the different levels of Drying time of surface coatings. These drying stages are easily recognizable visually, but chemically and physically challenging to define. A precise and repeatable determination of these drying stages requires... Automatic drying time tester like that NIP-DTR6800 suitable for automatically performing the test under controlled and constant conditions.

The testing method involves applying coating materials to Glass strips (300 mm × 25 mm). The paints or coatings are applied with a Film Squeegee evenly applied. The coated glass strips are then placed in the sample area of the Mechanical drying time tester inserted and the automatic test sequence started by pressing the start button.

During the exam hemispherical steel needles along the coating surface. The drying test is usually performed in 6-, 12-, 24- or 48-hour intervals carried out.

1. ASTM D5895 – Drying & Curing during Film Formation

ASTM D5895 describes the evaluation of the various drying and curing stages of organic coatings using linear mechanical recorder. The NIP-DTR6800 For this purpose, a hemispherical steel needle is moved over the freshly applied coating film under defined conditions.

ASTM-defined drying stages

• Set-to-Touch Time The coating begins to solidify and resists deformation. The needle leaves a pear-shaped mark.

• Track-Free Time The film carries the needle without sticking or tearing. The trace becomes narrower and more even.

• Dry Hard Time The needle no longer cuts or tears the film; only superficial traces remain visible. The film is sufficiently hardened for handling or packaging.

• Dry-Through Time The needle leaves no visible trace Furthermore – the film is fully hardened.

Mechanical recording principle according to ASTM

The NIP-DTR6800 reproduces the ASTM mechanism by:

• a hemispherical needle (1 mm or 2 mm tip),

• defined feed rate,

• standardized load (typically 5 g),

• Continuous documentation of the film interaction.

Engineers interpret the needle signature to precisely determine each drying stage.

Why ASTM D5895 is important

• Comparison of coating formulations

• Evaluation of solvent-based, water-based and high-strength systems

• Documentation of drying behavior under controlled conditions

• Determination of curing performance beyond the usual 8-hour work cycle

The NIP-DTR6800's multi-track system enables parallel testing of multiple samples and increases efficiency in laboratories and production controls.

2. ISO 9117-4 – Determination of drying behavior using a mechanical recorder

ISO 9117-4 is the international equivalent of ASTM D5895 and defines the drying time determination using linear mechanical recorder. The NIP-DTR6800 meets all ISO requirements regarding feed rate, needle specification, sample dimensions and environmental conditions.

ISO drying time analysis

ISO 9117-4 focuses on:

• Film education under standardized environmental conditions

• Interpretation of the needle signature to determine set-to-touch, dry-hard, and dry-through.

• Reproducible mechanical recording for global comparability

ISO emphasizes the importance of:

• controlled sample preparation

• uniform layer thickness

• stable temperature and humidity

• repeatable needle movement and load application

The precise drive system and stable load mechanism of the NIP-DTR6800 ensure full ISO compliance.

3. Application of the NIP-DTR6800 for ASTM & ISO drying time tests

Technical process

1. Sample preparation Uniform application of the coating according to ASTM D823.

2. Installation of the glass strip Inserting the coated glass strip into one of the test tracks.

3. Selection of test time 6 h, 12 h, 24 h or customer-specific intervals.

4. Load & needle size setting Use of the hemispherical needle according to ASTM/ISO.

5. Start of the test cycle The needle moves across the coating at a constant speed.

6. Analysis of the trace Identification of the transitions between the drying stages.

7. Documentation of the results Recording drying times for QC, formulation optimization or certification.

Technical advantages of the NIP-DTR6800

• Multi-sample platform for parallel testing

• stable feed rate

• precise load control

• high-resolution timing

• Ideal for water-based, solvent-based, alkyd, acrylic and 2K coatings.

• fully compliant with