阅读说明：本技术 一种麻纤维的无尿素喷墨印花预处理剂及预处理方法 (Urea-free ink-jet printing pretreatment agent and pretreatment method for fibrilia ) 是由 刘秀明 张敏 房宽峻 于 2021-09-10 设计创作，主要内容包括：本发明提供了一种适用于麻纤维的无尿素喷墨印花预处理液及预处理工艺,预处理剂包括0～3％羧甲基瓜尔胶、0～5％碳酸氢钠,余量为水；预处理工艺特征在于,将预处理搅拌均匀,然后通过浸轧的方式施加在织物上,然后烘干。用活性染料墨水对经过表面预处理的汉麻织物进行喷墨印花,然后经过汽蒸等工艺得到汉麻织物的喷墨印花产品。此预处理剂仅包括碳酸氢钠和羧甲基瓜尔胶,具有绿色环保,降低污水排放,降低成本的优点；同时用此预处理液处理过汉麻织物得到的喷墨印花产品,具有更高的颜色深度、图案更加清晰；本发明流程简单、易于操作,处理过程成本低能耗少,而且对纤维损伤小。(The invention provides a urea-free ink-jet printing pretreatment liquid suitable for fibrilia and a pretreatment process, wherein the pretreatment agent comprises 0-3% of carboxymethyl guar gum, 0-5% of sodium bicarbonate and the balance of water; the pretreatment process is characterized in that the pretreatment is uniformly stirred, then applied to the fabric in a padding mode and then dried. Carrying out ink-jet printing on the hemp fabric subjected to surface pretreatment by using reactive dye ink, and then carrying out steaming and other processes to obtain an ink-jet printing product of the hemp fabric. The pretreatment agent only comprises sodium bicarbonate and carboxymethyl guar gum, and has the advantages of environmental protection, sewage discharge reduction and cost reduction; meanwhile, the ink-jet printing product obtained by treating the hemp fabric by using the pretreatment liquid has higher color depth and clearer pattern; the method has the advantages of simple flow, easy operation, low cost and energy consumption in the treatment process, and small damage to the fibers.)

1. The pretreating agent for the jet printing of the fibrilia is characterized by being prepared from 0-3% of polymer, 0-5% of alkaline agent and water in a proportioning manner.

2. A fibrilia as claimed in claim 1, wherein the fibrilia is one of china-hemp, flax and ramie.

3. The pretreatment agent for inkjet printing of hemp fibers according to claim 1, wherein the polymer is at least one of sodium alginate, methyl guar gum, guar gum and hydroxyethyl methyl cellulose.

4. Carboxymethyl guar according to claim 1, characterized in that it has a degree of substitution of about 0.8.

5. The pretreating agent for inkjet printing of hemp fabrics according to claim 1, wherein the alkaline agent is at least one of sodium carbonate, sodium bicarbonate and sodium hydroxide.

6. A preparation method of a hemp fabric ink-jet printing pretreating agent is characterized by comprising the following steps: stirring and dissolving 0-5% of an alkaline agent in mass percent in distilled water, slowly adding an aqueous solution of a water-soluble polymer under stirring, wherein the mass of the water-soluble polymer accounts for 0-3% of the total mass of the pretreatment solution, and continuously stirring until the water-soluble polymer and the pretreatment solution are uniformly mixed to obtain the hemp fabric ink-jet printing pretreatment agent.

7. A process for pretreating a hemp fabric by ink-jet printing as claimed in claim 6, which comprises the steps of:

(1) the pretreatment liquid is applied to the surface of the hemp fabric by a two-dipping and two-rolling method,

(2) and (3) drying the hemp fabric subjected to the step (1).

8. The method for pretreating the hemp fabric by ink-jet printing according to claim 7, wherein the padding liquor ratio in the step (1) is 90-110%. In the step (2), the dried hemp fabric has a water content of 5-20%.

9. The pretreatment method of the pretreatment agent for inkjet printing of hemp fabric according to claim 7, wherein the hemp fabric pretreated with the polymer is subjected to inkjet printing with reactive dye ink, and then subjected to drying, steaming, washing and drying to obtain the inkjet printed product of hemp fabric.

Technical Field

The invention belongs to the technical field of digital ink-jet printing of textiles, and particularly relates to a urea-free ink-jet printing pretreating agent and a pretreating method for fibrilia.

Background

The fibrilia is a green, environment-friendly and healthy textile raw material, has a plurality of excellent properties such as good moisture absorption and dispersion, mildew and bacteria resistance, heat resistance, sun resistance and corrosion resistance, and also has the functions of shielding ultraviolet rays, dissipating sound waves and light waves and the like. The hemp can be used as antibacterial textile, and also as raw material for military clothes and high-grade textile, and has great development prospect.

The ink-jet printing technology for textile is also called digital ink-jet printing, and is characterized by that it utilizes various digital input means to input pattern into computer, after the colour separation treatment of computer, the various information can be stored in computer control centre, then the action of every colour ink nozzle can be controlled by computer, the required printed pattern can be sprayed on the surface of the fabric, and then the dye or pigment can be fixed on the fabric by means of after-treatment processes of fixing colour, etc. so as to obtain the invented textile with printed pattern. The ink-jet printing process can creatively produce differentiated high-quality fabrics with excellent color expression and high resolution, and can meet the ever-increasing demand of small-batch order markets; and can remarkably improve the phenomenon of resource waste caused by direct printing, so that the development of the ink-jet printing process is very rapid. As a printing mode without contacting with fabrics, the digital ink-jet printing machine ejects micro ink drops with different colors through a control nozzle according to instructions, and then the micro ink drops collide and mix on the surfaces of the fabrics to form a required printing pattern. Therefore, the interaction between the ink droplets and the fabric is critical, and the impact, spreading and absorption of the ink droplets on the fabric affect the quality and fineness of the printed pattern. If ink drops are directly sprayed on the untreated fabric, excessive bleeding of the ink drops on the fabric can result, and therefore pretreatment is required before inkjet printing of the linen fabric.

The prior pretreatment for ink-jet printing of linen fabrics mostly contains urea, for example, patent CN104131478A provides an ink-jet printing pretreatment agent for linen fabrics, which comprises sodium alginate, sodium bicarbonate, urea, anhydrous sodium sulfate and dye-resistant salt. The patent CN111501378A provides a pretreatment agent for inkjet printing of linen fabrics, wherein the pretreatment agent comprises nonionic cellulose ether, a moisture absorbent and an alkali agent, the pretreatment agent is padded on the linen fabrics, the patterns of the linen fabrics inkjet printed by the pretreatment process are clearer, and the color depth and the color fixation rate are improved; the process is easy to operate, short in flow and small in damage to fibers. The urea is used as a moisture absorption cosolvent in the steaming process, so that the internal transfer of dye into the fiber is facilitated, and the apparent color yield of the printed fabric is improved. However, the pretreatment agent is added with urea, which causes sewage discharge in the washing process and is not beneficial to ecological environmental protection. The patent CN111501382A provides a urea-free ink-jet printing pretreatment liquid and a pretreatment method for wool fabrics, wherein the pretreatment liquid comprises 0.5-3% of polymer and 0.5-2% of quaternary ammonium salt cationic surfactant; 0.1-4% of pH regulator. The jet printing wool fabric prepared by the pretreating agent has higher apparent color yield, good definition and bright color. But this process is not suitable for linen.

The application provides an ink-jet printing pretreating agent and a pretreating process for linen fabrics, and the ink-jet printing product has good color depth and definition.

Disclosure of Invention

The invention aims to research and explore related processes suitable for the pretreatment of the inkjet printing of the hemp fabric and provide technical and theoretical bases for further solving the problem of light color after the inkjet printing of the hemp fabric; improves the ink-jet printing effect of the linen fabric and also has the advantage of environmental protection.

In order to solve the problems, the invention adopts the technical scheme that: the urea-free ink-jet printing pretreatment agent for the fibrilia and the pretreatment method are characterized in that the pretreatment liquid comprises the following components in percentage by mass: 0-3% of a polymer; 0-5% of an alkaline agent; the balance being water.

A pretreatment method of a hemp fabric ink-jet printing pretreatment agent is characterized by comprising the following steps:

(1) the pretreatment liquid is applied to the surface of the hemp fabric by a two-dipping and two-rolling method,

(2) and (3) drying the hemp fabric subjected to the step (1).

Preferably, the hemp fiber is hemp fiber.

Preferably, the polymer is at least one of sodium alginate, carboxymethyl guar gum, guar gum and hydroxyethyl methyl cellulose.

Preferably, the carboxymethyl guar gum has a degree of substitution of about 0.8.

Preferably, the alkaline agent is at least one of sodium carbonate, sodium bicarbonate and sodium hydroxide.

Preferably, the preparation method of the hemp fabric ink-jet printing pretreating agent is characterized by comprising the following steps of: stirring and dissolving 2% of an alkaline agent in mass percent in distilled water, slowly adding an aqueous solution of a water-soluble polymer under stirring, wherein the mass of the water-soluble polymer accounts for 0-2.5% of the total mass of the pretreatment solution, and continuously stirring until the water-soluble polymer and the pretreatment solution are uniformly mixed to obtain the hemp fabric ink-jet printing pretreatment agent.

Preferably, the mangle ratio of padding is 90-110%. In the step (2), the dried hemp fabric has a water content of 5-20%.

The hemp fabric pretreated by the polymer is subjected to ink-jet printing by using reactive dye ink, and then the ink-jet printing product of the hemp fabric is obtained through the steps of drying, steaming, washing, drying and the like.

The beneficial effect that uses above-mentioned technical scheme to produce lies in: the pretreatment liquid is used for pretreating fabrics, so that the hemp ink-jet printing fabrics have clearer patterns, and the ink-jet printing products have higher color depth. In addition, the method has the advantages of short treatment time, simple and convenient process flow and small damage to the fabric.

Detailed Description

The technical solutions in the embodiments of the present invention are described more clearly below, and it is obvious that the described embodiments are only a series of embodiments of the present invention, and all other embodiments obtained by those skilled in the art without making any inventive step belong to the protection scope of the present invention.

In the following description, specific details are set forth in order to provide a thorough understanding of the present invention, which may be practiced otherwise than as described, and thus is not intended to be limited to the specific embodiments disclosed below.

In the following examples, the main materials involved:

the hemp fabric is a hemp plain fabric with gram weightIs 188g/m²Purchased from textile, llc, shanxi oasis;

the printing and dyeing grade sodium alginate is industrial grade and purchased from Qingdao Mingyue seaweed group Limited company;

the carboxymethyl guar gum is of industrial grade and is purchased from Yinuo chemical Co., Ltd, Ningpo;

sodium bicarbonate was analytically pure and purchased from Tianjin Kemi European chemical reagent, Inc.;

the reactive dye ink is of industrial grade and purchased from Hangzhou Honghua digital science and technology, the dye structure of the ink is monochlorotriazine type, and the viscosity range of the ink is 15-40 mpa & s;

the ink-jet printing effect of the invention is verified by the color data and the anti-seepage performance of the ink-jet printed fabric.

Since all experiments cannot be performed in the same batch due to practical limitations of inkjet printing equipment and production, the following examples are performed in batches according to variable factors, and different batches of printed fabrics have different inkjet performance detection results due to fluctuations of inkjet amount, printing patterns and other process conditions, so that there is no comparability between data obtained by inkjet printing of different batches.

Example 1

The formula of the ink-jet printing pretreatment liquid suitable for the hemp fabrics comprises the following components in percentage by mass: 1.5% of carboxymethyl guar gum, 2% of sodium bicarbonate and the balance of water.

The pretreatment method comprises the following steps: the polymer was slowly added to a certain amount of water at a stirring speed of 500r/min using a stirrer RW20 to obtain a 4% polymer raw paste, left overnight, the above-mentioned amounts of urea and sodium bicarbonate were weighed and stirred uniformly with a certain amount of water, and then 37.5% raw paste (the amount of the polymer was 1.5%) was weighed and then stirred uniformly at a stirring speed of 500r/min to obtain a surface pretreating agent.

The prepared pretreating agent is padded on the hemp fabric by a horizontal padder P-B0 through a two-padding and two-rolling procedure, and the pressure at two sides of a press roll is 0.1kg/cm²The mangle rolling rate is controlled to be 90-110% in the process, and padding is carried outAnd (3) flatly placing the hemp fabric of the pretreating agent in an oven at 60 ℃ for drying to obtain the pretreated hemp fabric. And (3) carrying out ink-jet printing on the treated fabric by using reactive dye ink, drying the printed fabric in an oven at 60 ℃, steaming for 10min, and drying after a water washing process (cold water washing → warm water washing → soaping (2g/L soap chips) → warm water washing → cold water washing) to obtain the ink-jet printed hemp fabric.

Comparative example 1

The pretreatment agent was prepared according to the method of example 1, and the hemp fabric was treated to complete the inkjet printing, except that the pretreatment agent in this comparative example was 1.5% carboxymethyl guar gum, 10% urea, 2% sodium bicarbonate, and the balance water.

Comparative example 2

The pretreatment agent was prepared and the hemp fabric was treated according to the method of example 1, and then ink-jet printing was performed, except that the pretreatment agent for conventional ink-jet printing of cellulose fiber was 2% sodium alginate, 10% urea, 2% sodium bicarbonate, and the balance water in this comparative example.

The hemp fabrics pretreated in the experimental example 1 and the comparative examples 1 and 2 were subjected to ink-jet printing, drying, steaming and water washing subsequent treatments in the same batch, and the color data and the line width of the hemp fabrics subjected to ink-jet printing were measured, and the results are shown in tables 1 and 2.

TABLE 1 influence of different pretreatments on the color index of inkjet printing of hemp fabrics

Fabric	L*	A*	B*	C*	h°	K/S value
							Example 1	36.55	48.30	4.40	48.50	5.21	12.23
Comparative example 1	38.53	48.69	0.12	48.69	0.14	10.74
							Comparative example 2	41.49	44.25	-0.99	44.26	358.72	7.63

Testing color data by using a Datacolor SF-600plus, measuring the inkjet printing color block of the hemp fabric under a D65 light source and a 10-degree visual angle, folding the monochromatic color block to be measured four times, placing the folded monochromatic color block in front of a color measuring hole of a color measuring instrument, fixing, and randomly taking 8 points to measure the color data, so that the error is less than 0.1. The calculation formula of the apparent color depth K/S value of the fabric is as follows:

K/S＝(1-R)²/(2×R)；

where K represents the absorption coefficient of the fabric for light, S represents the scattering coefficient, and R represents the reflectance at the wavelength of maximum absorption of the dye.

TABLE 2 influence of different pretreatments on inkjet printing line widths of hemp fabrics

Fabric	Radial line width	Width of weft
			Example 1	413	530
Comparative example 1	464	573
			Comparative example 2	545	626

The width of the printed lines is measured by using an RH-2000 biological phase optical microscope to represent the anti-seepage performance of the fabric, the average value of the lines subjected to ink-jet printing on the hemp fabric is obtained through multiple measurements, and the thinner the width of the lines is, the better the anti-seepage performance of the fabric is.

According to the data in the table 1, taking magenta as an example, the brightness value L of the inkjet printing hemp fabric treated by the carboxymethyl guar gum is smaller, which indicates that the color of the fabric is dark; the K/S value of the fabric treated by the carboxymethyl guar gum is larger than that of the fabric treated by the sodium alginate, wherein the K/S value of the color depth of the fabric obtained in example 1 is the largest, which shows that the pretreatment provided by the invention can obviously improve the apparent color depth of the reactive dye ink-jet printing fabric. The data in table 2 show that the China hemp fabric pretreated by the carboxymethyl guar gum has smaller width of lines in the warp direction and the weft direction than the China hemp fabric pretreated by the sodium alginate, wherein the fabric obtained in example 1 has the smallest line width, the better anti-seepage performance and the higher definition of the ink-jet printing pattern.

Example 2

The pretreatment solution is prepared according to the method in the example 1 to pretreat the hemp fabric, and then the treated fabric is subjected to post-treatment such as ink-jet printing, and the polymer dosage in the example 2 is different from the example 1, wherein the mass percentages of the carboxymethyl guar gum are respectively 0%, 0.5%, 1%, 1.5%, 2% and 2.5%.

The hemp fabrics pretreated in the embodiment are subjected to ink-jet printing in the same batch, and are subjected to subsequent treatment of steaming and water washing, and color data and bleeding property of the hemp fabrics subjected to ink-jet printing are measured. The results are shown in Table 3.

TABLE 3 influence of Polymer dosage on inkjet printing color index of reactive dyes for hemp fabrics

The data in table 3 show that, in the case of the cyan ink, as the mass concentration of the carboxymethyl guar gum in the pretreatment agent increases, the brightness of the printed fabric gradually decreases, indicating that the fabric becomes darker, the color saturation C of the treated fabric increases, and the vividness also increases with the increase of the mass concentration of the polymer. The apparent color depth K/S value is increased continuously, reaches the maximum value when the concentration is 1.5 percent, and the color depth of the fabric is the maximum.

Example 4

Different from the method of the embodiment 1, the pretreatment solution is prepared according to the method of the embodiment 1 to pretreat the hemp fabric, and then the subsequent treatments such as ink-jet printing and the like are carried out on the treated fabric, wherein the mass percentages of the sodium bicarbonate are respectively 0%, 1%, 2%, 3%, 4% and 5%.

The hemp fabric pretreated in example 4 was subjected to ink jet printing in the same batch, and to subsequent treatments of steaming and washing, and color data measurements were performed on the hemp fabric subjected to ink jet printing, and the experimental results are shown in table 4.

TABLE 4 influence of sodium bicarbonate dosage on inkjet printing color index of reactive dyes for hemp fabrics

As can be seen from the data in Table 4, taking cyan as an example, the addition of the alkaline agent to the pretreating agent can significantly reduce the brightness L of the printed fabric, the apparent color depth K/S value increases with the increase of the sodium bicarbonate concentration and then slightly decreases, and the color of the printed fabric reaches the deepest when the mass fraction of the sodium bicarbonate is 2%.

Example 5

The pretreatment agent is prepared according to the method in the embodiment 1, and the hemp fabric is treated to complete the ink-jet printing, except that the steaming time of the printed fabric after the ink-jet printing in the embodiment 5 is 0-16 min. The hemp fabrics pretreated in example 5 were subjected to ink jet printing in the same batch, and after the drying and steaming washing steps, different ink jet printed hemp fabrics were obtained, and the color data of the printed hemp fabrics were tested, and the results are shown in table 5.

TABLE 5 influence of steaming time on inkjet printing color index of reactive dyes for hemp fabrics

As can be seen from the data in Table 5, taking cyan as an example, the brightness L of the steamed printed fabric is obviously reduced, the apparent color K/S value of the fabric is increased and then reduced along with the increase of steaming time, and when the steaming time is 12min, the color of the ink-jet printed product of the hemp fabric is deepest.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that modifications can be made by those skilled in the art without departing from the principle of the present invention, and these modifications should also be construed as the protection scope of the present invention.