JPS6352151B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Field of the Invention) The present invention relates to a dyeing method for imparting a sharp and clear printed image with high fastness to a fibrous structure using an inkjet method. (Prior art and its problems) Conventionally, as a method for printing an image on a fibrous structure, a screen printing method, a roller printing method, and a transfer printing method have been adopted. however,
These methods have the following drawbacks. (1) Screen printing method Screens and rollers must be manufactured each time the design is changed, which requires a great deal of labor and preparation time before actual production. Therefore, this method is not only economical, but also lacks the high-mix, low-volume production and instant printability (speed) required in today's diversified fashion world. (2) Transfer printing method Similar to (1), this method also requires plate making for gravure printing, etc., and lacks productivity in small quantities of a wide variety of products and instant printability. Also,
The use of transfer paper is also a factor in increasing costs. (3) Inkjet printing method This printing method is generally used to draw characters and figures on paper. Even if fabric is printed using this method, the fabric is not as absorbent as paper, and because the fiber structure and textile structure have directionality and voids, the ink bleeds significantly and it is difficult to obtain clear patterns. Defects occur. There is a method of pre-heating the fabric to be treated in order to improve this problem, but this method has a limit on the amount of droplets that can be ejected, limits the design and color density, and also causes shrinkage of the fabric due to preheating. There is a drawback that gender changes the design. (Object of the Invention) In view of the shortcomings in the prior art, the present inventors have discovered that a wide range of droplet amounts can be used in a method for applying patterns on fabric by inkjet.
As a result of intensive research into a printing method that is free from bleeding and color density restrictions, we discovered that by gelling the ink droplets that fly onto the fabric, it is possible to achieve extremely clear and deep-colored printing. This invention has been achieved. That is, the present invention has provided an inkjet dyeing method that has a wide range of color densities and excellent clarity. (Structure of the Invention) (1) When dyeing a fiber structure by the inkjet method using a dye ink, the dye ink is mixed with a gelatinizing paste to make the viscosity 200 cps or less, and the dye ink is mixed with the gelling paste in advance. 1. An inkjet dyeing method comprising spraying the dye ink onto a fiber structure pretreated with a gelling agent to gel the dye ink on the surface of the fiber structure. (Mechanism of action of the invention) What is important in the invention is that the dye ink is gelled on the surface of the fabric. To achieve such gelling, dye ink gelling agents are used. These methods include a method in which a gelling agent is applied to the fiber structure in advance, and then a dye ink containing a sizing agent that gels with the gelling agent is applied, or a sizing agent to be gelled is applied to the fibrous structure in advance. One method is to apply the gelling agent to the object and then apply a dye ink containing a gelling agent, but the former method is preferable from the viewpoint of texture. Gelation in the present invention means that a low-viscosity dye ink becomes highly viscous, and the entire ink loses its fluidity and threadability. Examples of gelling agents having such an effect include inorganic metal salts and surfactants. Furthermore, among the gelling agents for inorganic metal salt compounds,
For example, metal salts such as stannous sulfate, barium chloride, nickel chloride, calcium chloride, magnesium chloride, and potassium chloride are easy to use because they are easy to treat as waste liquid, but chromium acetate, chromium nitrate, cadmium nitrate, zinc chloride, and lead acetate , mercury chloride, etc. are difficult to treat as waste fluids and cannot be used in practice due to environmental concerns, so care must be taken. In addition, strong acids and strong alkalis such as sulfuric acid and caustic soda have the disadvantage of embrittling fiber structures and accelerating the decomposition of dye inks, and tannic acid causes yellowing during pretreatment, so these gelation Agents also require caution when used. Next, typical combinations of sizing agents and gelling agents are illustrated, but the present invention does not need to be limited to these gelling agents. In short, in the present invention, the object of the present invention is achieved if the dye ink gels on the surface of the fiber structure, and any embodiment that substantially exhibits this effect is applicable to the present invention. . Typical combinations of sizing agents and gelling agents CMC (carboxymethylcellulose): aluminum sulfate, stannous chloride, cationic activator, cationic dye Locust bean gum: tannic acid, borax thorium alginate: aluminum sulfate, calcium chloride, magnesium chloride, Potassium chloride, stannous chloride, barium chloride, cation activator polyvinyl alcohol: tannic acid, boric acid,
Borax, aluminum sulfate The concentration of such gelling agents depends on the sizing agent.
It is 100g/or less, preferably 0.5-10g/. When applying a gelling agent as a pretreatment, use the pad method,
Although it can be applied by any method such as spraying or dipping, the pad method is preferred because it provides excellent uniformity. The dye ink is used after being thickened with the above-mentioned sizing agent, and such sizing agent may be used alone or in combination. Among these adhesives, sodium alginate is excellent in terms of film strength and is most preferred in achieving the object of the present invention. Polyvinyl alcohol (PVA) is then preferably used. In the case of ink that uses sodium alginate as a sizing agent, barium chloride, gelling agent, etc.
Calcium chloride is most preferred. Furthermore, in the case of inks using PVA as the sizing agent, borax is most preferably selected as the gelling agent. The concentration of such a sizing agent varies depending on the sizing agent used and the desired viscosity, but for example, in the case of thorium alginate, it is 20 g/or less, preferably 0.5
~10g/. The dye ink used in the present invention is an ink whose main medium is water, such as a water-based ink made of a water-soluble dye or a water-dispersible ink made of a water-insoluble dye. The dye for such ink is appropriately selected depending on the type of fiber, and water-soluble dyes include acid dyes, cationic dyes, direct dyes, metal-containing dyes, reactive dyes, etc. Examples of dyes include disperse dyes, vat dyes, naphthol dyes, sulfur dyes, and pigments. As described above, the dye ink of the present invention is mainly composed of dye and water, but if necessary, it may contain a fungicide, an oxygen absorber, a chelating agent, and a nozzle within a range that does not interfere with gelation. Additives such as polyhydric alcohols may be added as ink drying inhibitors. For example, in the case of an ink containing sodium alginate as a sizing agent, the sizing agent has poor compatibility with the anti-drying agent and tends to generate insolubilized substances in the ink, which can cause ink nozzle clogging. There is a possibility that it will happen. Therefore, when this type of glue is used, it is preferable to select highly hydrophilic glycols such as ethylene glycol and glycerin as the drying inhibitor. When a dye ink containing a gelatinizing sizing agent is jetted onto a fiber structure pretreated with a gelling agent using an inkjet, the ink instantly gels on the fabric surface without causing any bleeding, creating a sharp printed image. manifest. The inkjet method used in the present invention includes, but is not limited to, an electrostatic suction method, an ultrasonic vibration method, and a piezo element method. In short, any structure is sufficient as long as it is capable of ejecting ink in the form of droplets either continuously or at any time, the direction can be controlled as required, and it is capable of imparting a printed image to a printing medium. The dye ink thus gelled on the surface of the fiber structure is dried and then subjected to a fixation coloring treatment. The fixation color development treatment may be carried out using either dry heat or moist heat, but it may be carried out under the fixation conditions normally employed for the fiber. For example, in the case of polyester fibers, it is usually heated to 130°C by moist heat (saturated steam) treatment.
for 30 minutes and dry heat at 180-220℃ for 90-60 seconds. After such fixation coloring treatment, it is preferable to soap the film for the purpose of improving fastness. The fiber structure as used in the present invention includes fabrics such as knitted fabrics and nonwoven fabrics, carpets, paper-like materials, etc., made of synthetic fibers, semi-synthetic fibers, or natural fibers. (Effects of the Invention) According to the present invention, since the dye ink jetted by the inkjet method is reliably gelled on the surface of the fiber structure, an extremely sharp and clear printed image without bleeding can be obtained, and at the same time, a high dyeing rate can be obtained. It exhibits the effect of providing fastness. The present invention does not require a plate-making process such as screen printing or transfer printing, and has the advantage that it is extremely simple and can provide various images at any time. The present invention will be further explained below with reference to Examples. Example 1 A highly twisted fabric (palace) made of polyester fibers was pretreated using barium chloride as a gelling agent under the following conditions. The pretreatment liquid was padded with a squeezing rate of 62% and dried at 100°C for 10 minutes. Barium chloride was used as a pretreatment liquid at 0, 0.5, 1,
A total of 7 levels of treatment solutions were prepared, each containing 5, 10, 50, and 100 (g/). Next, the following seven types of identical inks having different viscosities and dye concentrations were prepared as dye inks. Dye: Kayalon Polyester Blue TS (manufactured by Nippon Kayaku; disperse dye): 0.2 parts Sizing agent: Sodium alginate (4%) (manufactured by Kimitsu Chemical: sizing agent): 0 to 30 parts Medium: Ion exchange water The viscosity of the dye ink is B when the amount of the glue added above was changed and the total amount was adjusted to 100 parts with ion-exchanged water.
Type viscometer measurement values (cps): 2, 5, 11, 17,
They were 38, 100, and 275. Using this ink, jet printing was performed on the above-mentioned pretreated fabric using an on-demand inkjet to create a total of 49 types of print items. Inkjet conditions: Nozzle diameter: 60 μm Distance between nozzle and fabric: 1 mm Applied voltage: 20 V The printed product was fixed and colored at 200° C. for 90 seconds with dry heat. The results are summarized in Table 1 as diffusivity. The degree of diffusion is the ratio of the diameter of a dot on a fabric to the diameter of a flying ink droplet, and the smaller the value, the smaller the ink smearing and the better. From the results in Table 1, the degree of diffusion tends to decrease as the pretreatment concentration increases and as the concentration of sodium alginate increases. However, when the viscosity reaches 275 cps, the nozzle of the ink jet tends to become extremely dirty, resulting in uneven ink jetting. Therefore, the viscosity is preferably 200 cps or less. Further, the pretreatment concentration has a correlation with the texture, and as the concentration increases, the texture tends to harden, so the concentration of the pretreatment liquid is preferably 0.5 to 10 g/or less. In any case, compared to the case where an untreated fabric was used, the printed product according to the present invention had a significantly lower degree of diffusion, improved ink bleeding, and was able to provide sharp and clear images.

[Dye liquid composition]

Dye base material: CI Despers Red 72 10 parts Dispersant: Prunic dispersant (molecular weight 15500)
3 parts ion-exchanged water 97 parts Add 100 c.c. of glass beads to this composition and disperse with a sand grinder for 20 hours to give 10%
A dye solution was obtained. The following ink was prepared using this dye liquid. [Ink composition] Dye liquid (10%) 50 parts Ethylene glycol 30 parts PVA 1 part Ion-exchanged water 19 parts This ink was passed through a 5μ cut filter, and then degassed in a vacuum container. The resulting ink having a viscosity of 15 cps was applied to the pretreated fabric using the same method and ink jet conditions as in Example 1. Thereafter, it was fixed with superheated steam at 180°C for 10 minutes. The dot diameter (μ) and color development (L value) of the obtained dyed product were measured. The results are shown in Table 3. The dot diameter was determined by microscopic observation and is expressed as the major axis of one ink droplet. Color development (L value)
Macbeth spectrometer
Measured using MS2000 model, the lower the number, the more intense the staining is. As is clear from the results in Table 3, fabrics pretreated with boric acid or borax have smaller dot diameters, are prevented from bleeding, and have sharp edges at the edges due to the synergistic effect with PVA in the ink. Furthermore, a delicate pattern with excellent color development was obtained, but the ink did not react well with the fabric to which no gelling agent was added.
Even if PVA was included, the dot diameter was large, the bleeding was large, and only a blurry pattern could be obtained.

【table】

Claims (1)

[Claims] 1 When dyeing a fiber structure using the inkjet method using a dye ink, the dye ink is blended with a gelatinizing paste to have a viscosity of 200 cps or less, and the dye ink is gelled in advance by gelling the gelatinizing paste. An inkjet dyeing method comprising spraying the dye ink onto a fiber structure pretreated with a dye ink to gel the dye ink on the surface of the fiber structure.