Resolve printer ink and paper secrets (below)

"Gum" coating also has the distinction between soft and hard. The "hard" coating touches the surface of plexiglass and absorbs ink slowly. The type of ink is also more picky. The solvent of the ink is slightly inappropriate and cannot be absorbed. But its ink droplets spread little and the ink layer is thick enough to print the best photos. It does not absorb well the original inks of EPSON original ink, Canon original ink, and some HP printers.

The "soft" coating feels astringent, like touching the surface of a balloon. Absorption is fast and almost any ink can absorb it. But different papers have a great change in the color of the same ink. A sheet of paper on the EPSON printer performs well, but it is bluish on the HP printer. We estimate that the different inks have different diffusion rates. The reason for bluing may be that the blue ink spreads less and other inks spread more severely. The dot spread of such paper is usually relatively large, the softer paper, the better the ink adaptability, the more the paper spreads. The sharpness and color saturation of the picture are also worse. I suspect that this kind of paper is made of many tiny pores in "glue" to absorb ink quickly. The greater the proportion of voids, the better the ink absorption is, and it feels like foamed plastic (or foamed "glue"). However, micropores cause large diffusion of ink dots and the transparency of the coating decreases. Therefore, "soft" paper prints close to coated paper, not beautiful enough.

The clear-coated paper is only returned when the light strikes the bottommost white reflective layer, and the incident light is fully filtered by the dye layer, so the color saturation is highest; in the semi-transparent or opaque coating, the light is halfway through With continuous reentry, no dyes are fully filtered, so the saturation, maximum density, and darkness levels are not as good as clear coatings.

The strange thing is that "soft" paper is usually waterproof. It is possible that it absorbs ink mainly by its pores instead of "glue". Therefore, its "glue" can be insoluble in water. The waterproofness. Its surface tension can be specially modulated so that it can only be infiltrated with a specific ink, and the ordinary ink is just like it falls on the lotus leaf, and cannot enter the pores to bring out the ink.

If soft paper is indeed such a structure, its resistance to fading is also not very good. Hard paper is not covered in the room will not fade in 3-5 years, soft paper how? I don't use much. How are your experiences?

Since "hard glue" may absorb ink into its own molecular structure, temperature and humidity have a great influence on the speed at which it absorbs ink. When the room temperature is lower than 20 degrees and the humidity is low, many dark particles appear in the dark part due to ink absorption in situ and ink build-up occurs. When the room temperature exceeds 30 degrees and the humidity exceeds 80%, the picture will turn yellow, and the reason for this is still unknown. The optimum temperature and humidity for the use of "hard adhesive tape" should be 25 degrees Celsius and 50%-80% relative humidity. Paper that absorbs ink with micro-pores is generally much less demanding on the environment.

The paper for the light box is usually required to be high. Because the light box sheet requires a maximum density of 3.0 to look good. The incident light is filtered only once on the ink layer, and the density and color saturation appear to be lower. Inexperienced people and those who use poor quality light box paper are often overshadowed by gray film, probably due to insufficient ink.

Printing a transmissive film usually requires twice the amount of ink when printing a reflective sheet. This is not only a requirement for software, but also a higher requirement for printing paper.

There are two types of transparent and translucent translucent papers. Transparencies can only be used for transmission, such as the use of a projector, so less use, and few people do the work on the transparent film, its ink absorption is not very good, usually buy the film is difficult to absorb twice the ink the amount.

Most transmissive transmissive films use transflective backsheets. They can be used for both transmissive viewing and reflective viewing, and do not add a diffuser for light boxes, so they are widely used. The main quality indicators for backsheets are ink permeability and ink absorption.

Good backsheets are consistent for all colors of ink permeability. However, we have noticed that most poor-quality back-sheets do not pass well through several colors of ink, resulting in inaccurate colors when the backlight is not turned on. Most of the cheaper backsheets suffer from poor ink absorption, as the maximum density does not increase correspondingly when printing with twice the amount of ink, but the contrast and sharpness of the image are greatly reduced.
In general people's minds, the back-spray jets are also classified as powdery and gelatinous. We think this should be the difference between using small holes to absorb ink and using structure to absorb ink. Colloidal paper has a great selectivity for ink, but good colloidal paper has strong ink absorption and can reach a maximum density of 3.0 or more. Powdered paper absorbs ink moderately, usually reaching a density of 3.0, and a density of 2.3 can be achieved. However, silty paper is generally very good in ink permeability, and cheap gel paper is not good in ink permeability.

What is the main cause of fading?

What people are most worried about using printers to print photos is the fading problem. According to our observation, the main cause of fading is light-heat plus air. And this air has the greatest effect. There is nothing in the air other than oxygen that has the biggest influence on the color.

Photographs printed on "Hard Tape" will not fade in the room for 3-5 years without coating. Photographs of coated paper and rice paper, which are porous and exposed to very large air-surfaced materials, will fade significantly in 1 year. Photo-covered "Hard glued paper" photographs faded slightly on the sunny side of the house for half a year, and there was no visible fading in the year or even two years when the sun did not reach the sun. However, if the paper base is not plastic but airy, the shelf life is reduced by at least half.

Take the printed photo of the film over to the outside and reduce the shelf life by half. We once posted the printed image to the car in the summer and ran for a month outside. The color faded. This shows that the car's hot iron shell is extremely destructive of color.

However, if the photos were put on ultraviolet light and ordinary incandescent light, their fading speed was not significantly different. Therefore, the most important thing for long-term preservation of photos is: 1. Let the dye block the air; 2. Rare high-temperature glare is rare.

The pigment ink may be more durable because of its larger particles and less internal oxidation. Some mineral pigments are inherently stable, such as cinnabar, but it is not possible to use ink for printing.

Relationship between graininess and printing paper

The same printer, even if using alternative inks, has a small change in granularity. Related articles have also described the effect of software on granularity. Does the paper have any effect on the particle size? there must be.

In general, the paper particles with a large dot spread are relatively large. The principle of this is not hard to imagine. But in many cases the opposite is true. For example, someone gave us a sample of paper. After printing, we found that it had a very small grain size. He was trying to make a lot of customizations to him, but the sharpness of the photos has caused us to doubt it. A closer look at the microscope with a 50-fold microscope revealed that the ink dots of the paper were extremely diffusive, and the dots were all diluted in color (like the "flat particles" on the film), so they looked fine. In an opaque or translucent coating, this phenomenon is more common and often the finer the paper particles appear to be, the more diffuse the dots are. Therefore, we observe the graininess of a paper while simultaneously observing its sharpness, color saturation, maximum density, and whether the level of shadows is reduced is a more comprehensive observation and choice. This observation should be extended to the printing system. Because some printer systems allow you to select only a few types of paper.

Is print software likely to change the printer's suitability for paper?

However, we have found that the improvement of the printer's adaptability to the paper by the software is relatively limited. When you have already reduced the printing speed, there are a large number of non-uniform ink droplets in the dark area, and the ink distribution is changed by software. No use. Even lowering the speed by 50% at this time has no decisive significance. Therefore, basically do not believe that using certain software can improve the paper's adaptability.

The function of the film

Many people are very reluctant to accept the process of laminating films. Always emphasize traditional photographs. But can the traditional photo without a film touch it? Is it durable? According to our observations, the traditional photo preservation period is only half that of the lamination film.
The first major role of the film is waterproofing, which is not necessarily required for traditional photographs. The second major role is to prevent fading, which is required for both traditional and printed photographs. There is also an important role for the film, which may not be found by many people, because they use cheap films.

Applying a photo film with a low index of refraction to photos can greatly reduce the reflection of photos and increase the permeability. It is similar to the lens coating. Do not believe you try it.

However, it is too much trouble to cover the film. If you accidentally invent a simple and high-quality lamination process, that is, you can cover the film while printing, it will certainly be very popular. We still quietly look forward to!