To understand and predict the process of formation of image structure in inkjet printing system, simulation models to calculate drying and penetration behavior were developed. The drying behavior is calculated by considering evaporation from surface cell and diffusion caused by concentration distribution between neighboring cells, and it becomes possible to predict detailed dynamics of ink consisting of multiple liquid components and solid particle. The penetration behavior is calculated by solving pressure distributions in median pore structure to satisfy relationships between Laplace pressure and flow resistance. Then penetration behavior in media that has multiple pore structure such as coated paper is predicted. By using the simulation models, the mechanism of “smudge” phenomenon due to image fixing strength that is determined by image forming process including drying and penetration behaviors is clarified.
Until now, various microcapsules have been prepared and applied in many fields such as the electronic materials, the construction civil engineering materials, the pharmaceutical products materials, the agricultural materials, the information recording materials, the textile materials, the latent heat energy storage materials, the stationary materials, the cosmetics materials and the food ingredients. Also, it is actively tried to prepare the microcapsules with multiple stimuli-responsibility. In this report, the fundamentals of microcapsules such as the preparation methods, the functions and the purposes of microencapsulation, the advance information for preparing the microcapsules are introduced. Furthermore, the microcapsules applied in the various fields such as the self-healing materials, the latent heat storage materials, the food ingredients, the hybrid shell microcapsules are introduced.
Here we describe the capsule technologies of Morishita Jintan (MJ), Japan-based company, which provides services to customers through healthcare business and contract manufacturing of seamless capsules. Seamless capsule is a type of soft gel capsules and can be obtained by MJ's original dropping method. The history of MJ's seamless capsule technology is back to the early ‘70s. Since then, MJ has developed various types of seamless capsules with multilayered structure;2-layered capsules for oil-based flavors, 3-layered capsule for aqueous solution and hydrophilic solution of pharmaceutical active ingredients, 3-layered capsules with acid-resistance shell for protecting probiotic cells, and 4-layered capsules (capsule-in-capsule). MJ has applied the capsule technology to own products and contract manufacturing of seamless capsules for worldwide customers. Nowadays the application of MJ's capsule technology is not limited to the foods, cosmetics, and pharmaceuticals, but rather extending to wide range of industry such as daily items, housing products, logistics, machinery, and electronics. In order to respond to various customers' requests, MJ continues updating the core capsule technology for the conventional applications and developing novel capsule technologies for the new applications;seamless capsules with non-edible shells and microcapsules.
FUJIFILM developed several thermo/pressure sensitive recording materials which have been introduced the poly (urethane-urea) microcapsule. That microcapsule were prepared by an interfacial polymerization process, and we can control “the glass transfer temperature” and “the mechanical properties” of the microcapsule shell. So we had contributed to the high functionality for thermo/pressure sensitive materials.
Now, as the thermo sensitive material, we are continuing the business of Dry Thermal Imager “DRYPIX Lite” for medical. The recording film “DI-HT” for DRYPIX Lite is applying the microcapsule technology in order to achieve the long storage life and better transparency to attain enhanced image quality.
As the pressure sensitive material, “Pressure Measurement Film PRESCALE” which could measure visual verification of pressure distribution is sold. PRESCALE is applying the microcapsule technology in order to achieve the precisely measure wide range pressure, distribution, and balance.
In this paper, we describe the technologies for the formulation of poly (urethane-urea) microcapsule and explain the technologies which introduced to our materials.
Since the first report of self-healing materials using the microcapsule approach in 2000' s, numerous design principles have been reported for achieving the self-healing properties. The self-healing materials have been focused on the achievement of sustainable society. With the self-healing materials, it is expected to be reduced the resource depletion and environmental problems. Moreover, it is also possible to extend lifetime of functions of materials. The self-healing materials were prepared via mainly reversible cross-linkers. Recently, precisely designed copolymers have been reported to realize self-healing properties utilizing interaction between units on the copolymers. In this focus review, we are going to review historically important researches in the self-healing materials field and brand-new approaches.
The precoat process for bolts is a process technology in which a special nylon or high-reactive sealant is applied to the threads of bolts to add excellent locking and sealing functions to themselves.
Especially, micro encapsulation (MEC) process can provide functions such as sealing, locking and lubrication by applying microencapsulated sealing and locking agent to the threads of screws, bolts, plugs, pipes, etc.
MEC-processed screws and anaerobic adhesives have been used for thread parts in the industrial market for a long time, but in case of MEC process, adhesive is applied to the thread surface beforehand. Therefore, it has useful effects such as a good workability and preventing application defect.
Conventionally, organic solvents were used when processing microcapsules on the thread surface, but we developed aqueous type products from the viewpoint of environmental friendliness, and completed the lineup of aqueous type products to replace all solvent type products.
Here we introduce the features of each aqueous type product.
The encapsulation technique is a function separation technique. In electrophotography, an image is formed by fixing toner on paper. At that time, the toner is required to function as a powder at the stage of storage, transportation, replenishment and development. On the other hand, in the fixing stage, the toner must adhere to paper. Such a conflicting function is required for the toner.
Further, in a dual-component developer, a carrier is used to impart charge to the toner. In the developing section, the carrier is held by magnetic force, and charge is applied to the toner by frictional charging on the surface. Thus, a carrier is required to have a plurality of functions.
As described above, in order to exhibit contradictory functions and a plurality of functions, as a toner, a capsule toner in which functions are separated by a core and a shell is used and as a carrier, a resin-coated carrier in which a core is coated with a resin is used as an encapsulation technique.
In this paper, we will overview the history and explain the technologies.