Introduction To Bundle Like Microfiber Artificial Leather
Due to the increasing shortage of natural leather resources and the gradual enhancement of people's awareness of environmental protection, along with the continuous progress of industrial technology, spinning materials, spinning technology, tannery technology, dyeing and finishing technology have been developing rapidly, and a new product, which is superior to leather and completely simulates leather, has come into being.
One
Brief introduction of basic production for producing super fiber leather
(1) production of island fibers
At present, there are two ways to produce Sea Island microfiber.
One is the fixed island method: it is made of two component composite spinning technology. Its fiber cross section is a component with fine and dispersed state surrounded by another component. It is very similar to islands in the sea. Its island and sea components are densely evenly distributed in the length direction of fibers.
The number of islands is fixed and the size is the same.
Zero Point Zero Five
Daniel.
After spinning, the conventional fineness exists, and the fine fiber bundle can only be obtained by dissolving the sea ingredients in the post processing solvent.
Most of them are used on filament at present.
The two is the indefinite island method: it is made of two component miscible spinning technology, and the cross section of the fiber is also surrounded by another component in a fine and dispersed state. The island of the single fiber is uncontrolled on the microcosmic and is discontinuous in the length direction of the fiber, so it is more realistic with the actual island.
The number of islands is not fixed, the fineness is different, but the fiber is finer.
Zero point zero zero zero one
Daniel, its simulation skin is stronger.
After spinning, it is also found by conventional denier. Only after the solvent is used to dissolve the sea components, the bundles of ultra fine fiber bundles will be obtained.
Because its island is formed by stretching to form ultra fine fibers, it is not yet possible to produce filament yarn, but only to produce staple fibers.
(two) production of non-woven fabrics
Two methods of needling and spunlacing are used in the production of sea island fiber.
The former parts are formed by feeding fibers, forming a certain thickness of fiber layer through loosening, carding, and laying nets. Then the needles or high pressure water columns are used to intertwined the fibers, and the base cloth with certain thickness and density is made.
(three) tanning process
The base cloth is passed through a certain concentration.
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The resin was then rolled and washed to form a Beth like skin.
(four) dissolution separation processing
Bass, which is processed from tanning process, enters the lye (toluene), and dissolves the "sea" component at a certain temperature and time, and then dissolves the "sea" component to complete the opening of the fiber, forming a super fine fiber bundle and a network like structure.
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The cavernosum of the resin, so far, has genuine leather made of genuine leather.
(five) post processing of microfiber leather
The semi-finished products obtained by dissolving and separating processes need a series of finishing processes such as softening, dyeing and polishing to get the final products of different uses and styles.
Two
Dyeing of Sea Island microfiber artificial leather
Two point one
Main factors affecting dyeing
2.1.1
Fiber effect: because the fineness of nylon fiber in microfiber leather is only
0.0001-0.001
Daniel, the adsorption rate of dyes is very fast, levelling is very poor, and the finer the fiber, the poorer the levelness; the smaller the fiber, the larger the specific area, the poorer the color rendering; the finer the fiber, the easier the dye in the fiber moves to the fiber surface, the poorer the color fastness, the more fiber the more, the more dyestuffs used, the poorer the water washing fastness and the rubbing fastness.
Therefore, dyeing of microfiber artificial leather has become a worldwide problem.
2.1.2
The influence of non-woven fabric: if the thickness of non-woven fabric is uneven and the fiber distribution is uneven, the dyeing effect will also be affected.
2.1.3P
U
Effect of resin: if used in microfiber leather
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The uneven distribution of resin will also affect the dyeing effect, and the coloring properties of different resins will also affect the dyeing effect.
2.1.4
Influence of dyes, auxiliaries and dyeing technology: different dyes, auxiliaries and dyeing processes affect dyeing effect.
Two point two
Dyeing mechanism
2.2.1
The dyeing mechanism of nylon fiber: nylon fiber is amphoteric fiber. It can adsorb hydrogen ions in the dye solution with positive charge and adsorb the hydroxyl ions in the dye solution with negative charge. Therefore, it can be dyed with ionic dyes.
For example, acid dyes, neutral dyes, reactive dyes, direct dyes, basic dyes can be used.
2.2.2P
U
Dyeing of resins: macromolecules in polyurethane contain amide groups which can be combined with acidic and neutral dyes to meet the dyeing requirements.
Two point three
Dyeing
Because the island microfiber artificial leather is composed of ultra-fine nylon fiber and polyurethane, ultrafine nylon fiber has the advantages of fast dyeing speed, poor levelling, poor dyeing depth, high dye consumption and low color fastness. Polyurethane has different affinity with the fiber to dye and affects the uniformity of dyeing. So dyeing is very difficult.
Our company has done a lot of experiments on dyeing chemicals, auxiliaries and dyeing processes. We have selected suitable dyes and auxiliaries, determined the appropriate dyeing process, achieved the goal of dyeing evenly, dyed deep, dyed and maintained high color fastness, so that our products have won wide acclaim from users.
2.3.1
The determination of dyes: whether the product can be dyed evenly, dyed, without chromatic aberration and good fastness depends mainly on dyes.
In addition, the choice of dyes should first take care of the good dyeing properties of the fibers, and also have a good dye uptake for polyurethane.
Under the guidance of the relevant companies and under the guidance of university professors, we have carried out a lot of experiments. The main selection is acid dyes, and some neutral and disperse dyes are used to dye island superfine artificial leather.
Dyes should have the following properties: good lifting property, high dye uptake rate, easy to dye dark color, good levelling property, good reproducibility, good pfer and dyeing, good covering property, good compatibility, good sunlight resistance, sublimation and dry and wet fastness, and little heat migration.
2.3.2P
H
Control of value:
PH
The value of dye directly affects the dye uptake, dyeing speed, levelness and penetrability, and also affects the strength of leather.
PH
The lower the value, the faster the dye uptake rate is, which is conducive to the improvement of dye uptake, but will affect leveling and penetrating.
PH
The value should be determined according to the properties of dyes, the amount of dyes, auxiliaries and equipment.
PH
The choice of the value is
Four
reach
Eight point five
It is generally regulated by an acid releasing agent.
2.3.3
Control of dyeing temperature: the dyeing temperature of dyeing is generally
Thirty-five
Temperature
The highest holding temperature is generally
One hundred
-110
Temperature
。
Low dyeing temperature will reduce dye uptake, and then affect leveling and penetrating. Dyeing temperature is high, which is good for leveling and dyeing, but will affect the handle of leather.
In addition, the heating rate also affects leveling and dye penetration. The temperature rises quickly and dyes quickly, and it is not easy to dye evenly and dye thoroughly.
2.3.4
The setting of dyeing time: the dyeing time is determined by the depth of dyeing.
40-120
The deeper the minutes, the longer the time.
2.3.5
Selection of dyeing auxiliaries: different auxiliaries such as levelling agent, penetrating agent, lubricant and acid releasing agent are used in dyeing.
Selecting suitable auxiliaries is beneficial to dyeing effect, and can improve the levelness and penetrability of dyes.
Leveling agents achieve the purpose of leveling and dyeing through reducing dyeing speed or enhancing dye pfer.
Osmosis agent is used to accelerate dye penetration into leather to achieve leveling and dyeing.
The acid releasing agent is used for stabilization and control.
PH
And then control dyeing speed and improve leveling.
2.3.6
Dyeing and finishing: there are super fine nylon fibers and numerous microporous polyurethane in the island microfiber artificial leather. Therefore, after dyeing, there are many adsorbed residual dyes on the surface and micro air of the fibers. These direct effects on color fastness must be removed, usually washed with water, and when necessary, fixing agents are used to improve the color fastness.
Generally, light color is directly washed with water, medium color is washed with detergent, dark color is treated with fixing agent.
2.3.7
Dyeing pretreatment: there are various impurities in Sea Island artificial leather, which affect the dye uptake, and are not conducive to dyeing and finishing. Therefore, pre dyeing is necessary to remove impurities.
2.3.8
General dyeing process: levelling agent.
1-3%
Osmotic agent
One
-3
gram
/
Adjustment of acid releasing agent
PH
Value to
4-8.5
, add the dye needed, and follow the rising temperature.
Forty
Temperature
Press
One
Temperature
/
Minutes rise to
Seventy
Temperature
Press
Zero point three
Temperature
/
Minutes rise to
One hundred
Temperature