Behavior Time of Different Materials: A Relative Observation

When comparing materials such as alcohol ink, pigment production systems, acrylic paint, pan watercolors, and oil pastels, "behavior time" is not a fixed absolute value.

The exact same material displays different durations under varying substrates, coating thicknesses, ambient temperatures, humidity levels, formula compositions, and human interventions. Therefore, the timeframes stated here are not fixed standards inherent to a material, but rather a relative average range extracted from long-term observations and extensive sample records.

The core focus of observation here is the process of a material from the moment it begins to change noticeably until that change temporarily or permanently stops:

• The starting node of the material's behavior;
• The duration of the behavior;
• Factors that accelerate or slow down the behavior;
• The termination mechanism of the behavior (whether it ends naturally by the material itself or is stopped by human judgment);
• The physical conditions for the material to re-enter a mutable state after the behavior ends.

The length of a material's behavior time reflects the combined effect of three levels: the properties of the material itself, the external environment (such as temperature, humidity, airflow, and surface absorbency), and human intervention (such as heating, adding water, adding mediums, stirring, grinding, spreading, applying pressure/friction, or pausing operation). Human intervention alters the duration during which a material remains in an "active behavior state."

Furthermore, the duration of behavior time serves purely as a physical expression of material behavior. It involves no evaluation of whether a material is superior or inferior, nor does it constitute a judgment on its practical value.

1. Alcohol Ink: Short Behavior with a Clear End

For alcohol ink and other liquid materials with obvious volatility, behavior begins the moment the liquid leaves a closed container and comes into contact with open air.

In samples on small non-absorbent surfaces with human hot-air intervention, the relative average time from noticeable movement to the basic completion of evaporation falls around 3–5 minutes in long-term observation.

Among the materials observed, alcohol ink belongs to the category with a relatively short behavior time.

Its behavior demonstrates a clear directionality: as the liquid enters the open environment, evaporation begins. As evaporation proceeds, the liquid gradually decreases, eventually leaving behind a solid residue or pigment trace, at which point the original volatile liquid state comes to an end. Once the alcohol evaporates, it does not spontaneously return to its original liquid state, making this process irreversible. Human interventions such as tilting the surface, altering airflow, or applying heat correspond to varying degrees of change in evaporation speed.

2. Pigment Systems: Long-Cycle Changes Composed of Multiple Stages

Extending the observation of pigment from its initial powder state to the final formation of pan watercolors presents an overall process composed of multiple continuous stages:

Influenced by factors such as the nature of the pigment itself, the binder system, the amount added, particle condition, and ambient temperature and humidity, the rate of change varies noticeably among different pigments. In long-term observations, mid-range samples take approximately 2–6 months for the entire change process.

This timeframe serves as an average reference under routine operations and does not include non-universal steps such as re-processing, re-grinding, or extra adjustments resulting from individual sample anomalies. The long behavior cycle of pigment systems corresponds to a extended transition process in which the material disperses from powder into liquid, and then gradually loses moisture to form a stable solid structure. Significant variations exist among different pigments, and this duration shares no direct correlation with the final quality of the paint.

3. Acrylic Paint: Solidification Process Influenced by Mediums and Thickness

Standard acrylic paint without added water or liquid mediums begins to lose fluidity within a few minutes to tens of minutes when applied thinly; as the coating thickness increases, the time required to lose fluidity lengthens accordingly.

When water or fluid mediums are added (such as creating fluid art on canvas, wood boards, or other surfaces that do not rapidly absorb moisture), the moisture evaporation process shows the following correlations:

• Substrate Area: The larger the area, the slower the overall drying process tends to be;
• Coating Thickness: The thicker the coating, the slower the internal moisture release tends to be;
• Medium Volume: Adding more water or liquid medium tends to extend the duration of the liquid state.

Using abstract fluid art as an observation sample, the time from spreading to a noticeable loss of fluidity displays a range from a few minutes, tens of minutes, to several hours; reaching complete dry solidification typically requires 1 day to several days. Once fully solidified, acrylic paint forms a stable solid state and no longer returns to its initial liquid form.

4. Pan Watercolors: Highly Correlated with Human Painting Activity

In a dry state without water intervention, pan watercolors remain in a solid state with no fluid behavior. When water is introduced, the solid pigment is re-activated, forming a liquid paint capable of moving, spreading, and diffusing.

During a single painting session, the behavior time of pan watercolors spans from a few minutes to several days. This variation correlates with multiple objective and operational factors:

• The size and absorbency of the paper and substrate;
• The painting technique (such as wet-on-wet or multiple glazing layers);
• The volume of water used and the frequency of re-wetting local areas;
• The point at which a person decides that a specific stage of painting has ended.

Unlike alcohol ink or cured acrylic paint, the evaporation and drying of moisture in pan watercolors does not mean the material has permanently lost its capacity for behavior. At any stage after drying, adding water again reactivates local or complete pigment back into a liquid state. Its "end of behavior" corresponds to the pause or termination of human painting activity, rather than an irreversible change in the physical properties of the material.

5. Oil Pastels: Open-Ended Behavior Time

Oil pastels remain solid at room temperature and do not undergo a drying or curing process like alcohol evaporation or moisture loss.

Under the influence of tools, pressure, friction, and human operation, oil pastels soften, shift, mix, and reshape. Taking the process of completing a standard artwork as an observation sample, single sessions of human operation typically fall between tens of minutes to several hours.

The pause of a single painting session does not mark the ultimate end of the oil pastel's material behavior. Provided no protective isolation layer is applied, tools can still be used to scrape, move, and adjust the material years after the work is finished. Therefore, the description of oil pastels leans toward: "How long a person continuously intervenes with it, and when that intervention is temporarily paused." Its behavior state remains open to future human operation over extended periods.

Summary: Relative Behavior Time and Termination Mechanism Comparison

Observing these materials together reveals distinct characteristics in their rates of change and how their "end of behavior" is defined:

The figures above are best understood as relative ranges and mid-range samples obtained from long-term observations, rather than strict absolute standards.

The key focus of observation among these materials lies in the fact that even if different materials ultimately transition from liquid to solid, the processes they undergo are entirely distinct. Some materials exhibit natural evaporation termination, some show multi-stage gradual solidification, while others, after temporarily pausing their current activity, still maintain the potential to be re-activated and reshaped.