KR101173798B1 - Artificial leather and method for manufacturing the same - Google Patents

Abstract

Disclosed are an artificial leather and a method of manufacturing the same, which greatly improve the feel and breathability while satisfying the level of flame retardancy required in the industry. Artificial leather of the present invention, a non-woven fabric, and a pre-artificial leather containing an elastic polymer resin in the nonwoven fabric; And a flame retardant composition layer partially coated on the preliminary artificial leather.

Artificial leather, flame retardant, tactile, breathable

Description

Artificial leather and method for manufacturing the same

The present invention relates to artificial leather and a method for manufacturing the same, and more particularly, to an artificial leather and a method for producing the same comprising an elastic polymer resin and a flame retardant composition.

Artificial leather is made by impregnating a polymer elastic body in a nonwoven fabric formed by interweaving microfibers three-dimensionally, and has a soft texture and unique appearance similar to that of natural leather, and thus makes shoes, clothing, gloves, sundries, furniture, and automobile interior materials. It is widely used in various fields such as.

Such artificial leathers are required to have higher functionality in terms of flexibility, surface quality, wear resistance, light resistance, or elongation, depending on the intended use, and various properties may be required at the same time.

For example, when artificial leather is applied to the skin material attached to a car seat among automotive interior materials, as the eye level of the consumer increases, quality characteristics of the surface, specifically, excellent appearance, breathability, and tactile properties are required, There is a difficulty in satisfying the flame retardancy specified in the statutory items among the physical properties.

In other words, in order to impart flame retardancy required by the industry, a large amount of flame retardant must be used, and when a large amount of flame retardant is treated, there is a problem that the feel of artificial leather is hard and the breathability is reduced.

Accordingly, the present invention relates to an artificial leather and a method of manufacturing the same, which can prevent the problems caused by the limitations and disadvantages of the related technology.

An advantage of the present invention is to provide an artificial leather and a method of manufacturing the same, which can satisfy the level of flame retardancy or higher required by the industry, and which has excellent touch and breathability.

Further features and advantages of the invention are described below, and in part will be apparent from such techniques. Alternatively, other features and advantages of the present invention may be understood through practice of the present invention. Objects and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

In order to achieve the above advantages, and according to the object of the present invention, a pre-artificial leather including a nonwoven fabric, and an elastic polymer resin impregnated in the nonwoven fabric; And a flame retardant composition layer partially coated on the preliminary artificial leather.

In another aspect of the invention, the step of preparing a pre-artificial leather; And partially applying a flame retardant composition on the preliminary artificial leather.

It is to be understood that both the foregoing general description and the following detailed description are intended to illustrate or explain the invention, and to provide a more detailed description of the invention in the claims.

According to the present invention, by partially applying the flame retardant composition on the preliminary artificial leather can not only provide the artificial leather with the flame retardancy more than the level required by the industry, but also improve the feel and breathability of the final artificial leather at the same time.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Therefore, the present invention encompasses all changes and modifications that come within the scope of the invention as defined in the appended claims and equivalents thereof.

As used herein, the term 'preliminary artificial leather' refers to artificial leather including a nonwoven fabric and an elastic polymer resin impregnated on the nonwoven fabric, and means an artificial leather immediately before a flame retardant composition is added.

Hereinafter, with reference to the accompanying drawings, an embodiment of the artificial leather and its manufacturing method of the present invention will be described in detail.

Figure 1 schematically shows the surface of the artificial leather of the present invention.

As shown in FIG. 1, the artificial leather of the present invention includes a preliminary artificial leather 100 and a flame retardant composition layer 200 formed by being partially applied onto the preliminary artificial leather 100.

The preliminary artificial leather 100 is an artificial leather including a nonwoven fabric (not shown) and an elastic polymer resin (not shown) impregnated in the nonwoven fabric as defined above, and means artificial leather immediately before a flame retardant composition is added. , By the method described below.

First, a sea island type fiber is manufactured through a composite spinning process. The island-in-the-sea fiber component may be nylon or polyester, and the polyester may be polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), or polybutylene terephthalate (PBT).

Subsequently, the island-in-the-sea fibers are cut into short fibers such as staple fibers through a cutting process. The island-in-the-sea fibers in the form of short fibers undergo a carding process and a cross lapping process to form a web. Alternatively, a spun bonding process may be used to form a web directly without a cutting process using island-in-the-sea fibers in the form of long fibers.

The plurality of webs thus formed are bonded to each other using a needle punch or a water jet punch to complete a nonwoven fabric.

Subsequently, the preliminary artificial leather 100 is completed by sequentially performing the step of impregnating the elastic polymer resin in the nonwoven fabric and the step of minimizing the sea component in the island-in-the-sea fibers. Optionally, the ultrafine process may be performed first, followed by the impregnation process of the elastic polymer resin.

The process of impregnating the elastic polymer resin in the nonwoven fabric may be performed by a coating process or a dipping process. Among these, a simple and easy dipping process will be described below.

First, the elastic polymer resin may be a polyurethane resin or a silicone-based resin. The polyurethane resin may be a polycarbonate diol resin, a polyester diol resin or a polyetherdiol resin alone or in combination thereof.

The impregnation process of the elastic polymer resin may be completed by sequentially performing a step of immersing the nonwoven fabric in the composition including the elastic polymer resin, a solidification process of solidifying the elastic polymer resin in a coagulation bath, and a process of washing with water in a washing tank. . The coagulation solution contained in the coagulation bath may be a mixed solution containing water and dimethylformamide.

In more detail, the ultrafine process is performed by using an alkaline solution such as an aqueous caustic soda solution to elute and remove the sea component from the composite fiber composed of the island component and the sea component. As the sea component is removed, the remaining island components form microfibers. The microfibers produced by the micronization step preferably have a fineness range of 0.3 denier or less from the viewpoint of touch.

In the above, the method for manufacturing the preliminary artificial leather 100 using the island-in-the-sea fiber was described, but the present invention is not limited thereto. After the production of the ultrafine fiber from the beginning, the nonwoven fabric is prepared using the nonwoven fabric. The preliminary artificial leather 100 may be manufactured by impregnating an elastic polymer resin.

The process of manufacturing artificial leather by partially applying a flame retardant composition on the preliminary artificial leather 100 prepared as described above is as follows.

First, a flame retardant composition is prepared. In order to manufacture an artificial leather having a flame retardant composition layer 200 having a suitable upper thickness (a) and a depth of penetration (b), it is preferable to prepare a flame retardant composition having a viscosity in a predetermined range. If the viscosity of the flame retardant composition is too high, the flame retardant composition may not penetrate smoothly into the interior of the preliminary artificial leather (100). On the other hand, when the viscosity of the flame retardant composition is too low, it is widely spread on the surface of the preliminary artificial leather 100, the breathability of the artificial leather is not uniform and flame retardancy is also reduced. The viscosity of such flame retardant compositions can be controlled using thickeners such as acrylics.

The flame retardant composition comprises a flame retardant and a binder. The flame retardant may be preferably a phosphorus flame retardant rather than a halogen-based flame retardant that is a carcinogen. The binder is used to improve adhesion, and various kinds of binders may be used for the flame retardant composition of the present invention. In particular, a urethane-based binder including silicon may be used. Since silicon has excellent heat resistance, decomposition of silicon may be suppressed during combustion and crosslinking with urethane may be formed, thereby improving the flame retardancy of artificial leather. On the other hand, the urethane-based binder not only has a strong adhesive strength with the preliminary artificial leather 100, but also has a good adhesive strength with other materials such as sponge.

Optionally, the flame retardant composition may be used by mixing various additives with the flame retardant and binder described above. As the additive, an antioxidant, an antistatic agent, an ultraviolet absorber, a hydrolysis inhibitor, a softening agent, or the like may be used.

As described above, when the flame retardant composition is prepared, the artificial leather of the present invention is manufactured by partially applying the flame retardant composition on the preliminary artificial leather 100. The partial coating may be performed by a printing method for printing, a gravure coating method, or a rotary screen coating method.

The printing method for printing is easy to form a striped image, while the rotary screen coating method may be easy to form a dot or honeycomb.

According to the present invention, the flame-retardant composition layer 200 of various shapes may be formed on the preliminary artificial leather 100 by partially applying the flame-retardant composition in various ways.

1 schematically illustrates a surface of an artificial leather in which a pointed flame retardant composition layer 200 is formed according to an embodiment of the present invention, and FIGS. 3 to 4 are stripe patterns in one direction according to another embodiment of the present invention. And the surfaces of artificial leathers each having an orthogonal striped (ie checkered) flame retardant composition layer 200 formed thereon, respectively. 2 schematically illustrates cross sections of A and A ′ of FIG. 1.

1, 3 and 4, the artificial leather of the present invention is manufactured by partially applying a flame retardant composition in the form of dots or stripes on the preliminary artificial leather 100, wherein the breathability and Depending on the level of flame retardancy, the size and density of the spots (pieces per square meter) may be appropriately adjusted or the width and density of the stripes (rows per square meter) may be appropriately adjusted.

The partially applied flame retardant composition layer 200 for producing artificial leather having a level of horizontal burn rate of 100 mm / min or less and a breathability of 20 to 50 L / min / 100 cm 2 as required by the industry. The area of, may be preferably occupying 10 to 70% of the surface area of the preliminary artificial leather (100).

The area of the partially coated flame retardant composition layer 200 means the area of the interface with the preliminary artificial leather (100). If the area of the partially applied flame retardant composition layer 200 is less than 10%, it is impossible to obtain artificial leather having a level of flame retardancy required by the industry, while the area of the partially applied flame retardant composition layer 200 is 70 If the percentage is exceeded, the breathability of artificial leather is drastically reduced.

2 is a cross-sectional view taken along line AA ′ of the flame retardant composition layer 200 of FIG. 1, wherein the flame retardant composition layer 200 protrudes above the surface of the preliminary artificial leather 100. It has an upper thickness (a) means a and a penetration depth (b) means the degree of penetration into the preliminary artificial leather (100).

On the other hand, the upper thickness (a) is a preliminary level in order to produce artificial leather having a level of flame retardancy of 100 mm / min or less and breathability of 20 to 50 L / min / 100 cm2 of the level required by the industry. It is preferably in the range of 0.1 to 4% of the thickness (c) of the artificial leather. If the ratio of the upper thickness (a) is less than 0.1%, it is impossible to manufacture artificial leather having the level of flame retardancy required by the industry, whereas if the ratio of the upper thickness (a) exceeds 4%, the artificial leather The touch may drop sharply.

The penetration depth (b) is preferably in the range of 5 to 50% of the thickness (c) of the pre-artificial leather. If the ratio of the penetration depth (b) is less than 5%, the adhesive strength is lowered and durability is reduced, while if the ratio of the penetration depth (b) exceeds 50%, the touch of artificial leather may be hard. The upper thickness (a) and the depth of penetration (b) can be taken by cutting the cross section of the sample and measured using an image analyzer (using the JVC Digital Camera KY-F70B in the software of Image-Pro Plus).

The artificial leather manufactured as described above has excellent flame retardancy such that the horizontal combustion speed measured according to the automotive interior combustion test regulation of FMVSS.No.302 is 100 mm / min or less and at the same time 20 to 50 L / min / 100 cm2. Has breathability.

The horizontal combustion speed is a method of measuring flame retardancy mainly when artificial leather is used as interior materials such as automobile seats. If the horizontal burning rate of artificial leather exceeds 100 mm / min, it may be difficult to use as interior materials for automobiles because it may not have the level of flame retardancy required by the industry.

The breathability of the artificial leather indicates the degree of passage of air into and out of the car seat when the artificial leather is used in the car seat. As the breathability increases, the driver feels comfortable, while the breathability decreases, the driver feels uncomfortable. However, if the breathability is excessively increased, as the content of the flame retardant composition layer 200 falls, the flame retardancy of artificial leather is excessively degraded. Therefore, it may be preferable that the breathability of the artificial leather has a range of 20 ~ 50 L / min / 100 cm 2.

Hereinafter, embodiments and comparative examples of the present invention will be described in detail. The present invention is to be understood only by the following examples and is not intended to limit the scope of protection of the claims.

Example  One

A molten solution of a sea component is prepared by melting a copolymerized polyester obtained by copolymerizing 5 mol% of a polyester unit containing a metal sulfonate in a polyethylene terephthalate, which is a main component, and melting polyethylene terephthalate (PET). Prepare a melt of the components. Thereafter, using a 50% by weight of the molten solution of the sea component and 50% by weight of the melt of the island component composite spinning to obtain a filament consisting of three denier single yarn and 16 island components in cross section, the filament at a draw ratio of 3.5 After stretching to prepare a island-in-the-sea filament-shaped fibers. Thereafter, the crimp process was performed to have a crimp number of 15 pieces / inch using the island-in-the-sea fibers, heat-set at 130 ° C., and cut into 51 mm to prepare an island-in-the-sea-type fiber in staple form.

Then, after forming the web through the carding process and the cross-lapping process of the island-in-the-sea fibers in the form of staples, the webs were subjected to a needle punch process to prepare a nonwoven fabric.

Thereafter, the nonwoven fabric was padded with an aqueous polyvinyl alcohol solution having a concentration of 5% by weight, followed by drying. The dried nonwoven fabric was obtained by dissolving the polyurethane in a dimethylformamide (DMF) solvent. Immerse in solution for 3 minutes. Thereafter, the non-woven fabric impregnated with the polyurethane solution was solidified in an aqueous solution of dimethylformamide at a concentration of 15% by weight and washed with water to obtain a non-woven fabric impregnated with polyurethane, that is, preliminary artificial leather (100). The artificial leather 100 had a unit weight of 350 g / m 2 and a thickness of 1.0 mm.

Thereafter, the polyurethane-impregnated nonwoven fabric was treated with an aqueous solution of caustic soda at a concentration of 5% by weight to elute the sea component in the composite fiber to carry out an ultrafine process to obtain a preliminary artificial leather (100).

On the preliminary artificial leather 100, a flame retardant composition comprising 40 wt% of water, 40 wt% of phosphorus flame retardant of ammonium polyphosphate, and 20 wt% of polyurethane-based binder, using a rotary screen coating method After applying a dot on one surface and drying by hot air at 150 ° C. for 2 minutes, an area of 50% of the surface area of the preliminary artificial leather 100, a diameter of 2 mm, an upper thickness (a) of 16 μm, and a penetration depth (b) An artificial leather having a flame retardant composition layer 200 having a thickness of 100 μm was obtained.

Example  2 to 3

The flame retardant composition was applied onto the preliminary artificial leather 100 prepared according to Example 1 to form a flame retardant composition layer 200 which occupies an area of 10% and 70% of the surface area of the preliminary artificial leather 100, respectively. Except that the artificial leather was obtained in the same manner as in Example 1.

Example  4 to 6

An area of 10%, 50%, and 70% of the surface area of the preliminary artificial leather 100 was applied by applying a flame-retardant composition on the preliminary artificial leather 100 prepared according to Example 1 in the shape of stripes as shown in FIG. Artificial leather was obtained in the same manner as in Example 1 except that the flame retardant composition layer 200 having a stripe width of 2 mm was formed.

Example  7 to 10

On the preliminary artificial leather 100 prepared according to Example 1 described above, except that the flame retardant composition layer 200 was formed by changing the conditions as shown in Table 1 below, the artificial leather was prepared in the same manner as in Example 1. Got it.

Comparative example  One

Artificial leather was obtained in the same manner as in Example 1, except that the flame retardant composition was applied to the entire surface of the preliminary artificial leather 100 obtained in accordance with Example 1 above.

Example  11 to Example  16

On the preliminary artificial leather 100 prepared according to Example 1 described above, except that the flame retardant composition layer 200 was formed by changing the conditions as shown in Table 1 below, the artificial leather was prepared in the same manner as in Example 1. Got it.

Next, the main physical properties of the Examples and Comparative Examples were measured by the following method, Table 1 shows the measurement results.

Flame retardant  Area ratio (%)

The flame retardant layer area ratio (%) represents the area of the flame retardant composition layer 200 formed on the preliminary artificial leather 100 relative to the preliminary artificial leather 100 surface area. The area of the flame retardant composition layer 200 was measured using an image analyzer.

Upper thickness ratio (%)

The upper thickness ratio (%) is, as shown in FIG. 2, from the average surface c of the preliminary artificial leather 100 to the flame retardant composition layer 200 drawn upward from the average surface c of the preliminary artificial leather 100. The average thickness of the upper thickness (a) is shown as a ratio. Each thickness was measured using an image analyzer.

Penetration depth ratio (%)

The penetration depth (b) ratio (%) is a flame retardant composition layer penetrating into the interior from the average surface (c) of the preliminary artificial leather 100, as shown in FIG. The penetration depth (b), which is the average depth up to 200), is expressed as a ratio. Each thickness and depth was measured using an image analyzer.

Horizontal burning rate measurement of artificial leather

The horizontal combustion speed (mm / min), which indirectly indicates the degree of flame retardancy of artificial leather, was measured according to the automotive interior combustion test regulations of FMVSS.

Breathability Measurement of Artificial Leather

According to ASTM D 737, the air permeability (L / min / 100 cm 2) was measured according to the Frazier method.

Measurement of touch (bending stiffness) of artificial leather

Bending stiffness (cm), indicating indirectly the feel of artificial leather, was measured using the FAST-2 system. The bending stiffness was obtained by measuring the bent length after bending the 150 mm x 50 mm specimen at 41.5 degrees by its own weight. The average value of the measured transverse and longitudinal directions was taken, and if the value was 100 or more, it was determined that the touch did not meet the standard.

division Application form Flame Retardant Area Ratio (%) Upper thickness ratio (㎛) Penetration depth ratio (㎛) Horizontal combustion speed (mm / min) Breathability (L / min / 100㎠) Bending stiffness (cm) Example 1 Store 50 16 100 40 31 80 Example 2 Store 10 16 100 80 46 77 Example 3 Store 70 16 100 Autonomous 25 95 Example 4 Stripes 10 16 100 90 43 76 Example 5 Stripes 50 16 100 55 28 82 Example 6 Stripes 70 16 100 Autonomous 22 94 Example 7 Store 50 2 100 45 43 74 Example 8 Store 50 40 100 30 26 97 Example 9 Store 50 16 60 60 39 76 Example 10 Store 50 16 450 Autonomous 21 98 Comparative Example 1 Front coating 100 16 100 Autonomous 4 105 Example 11 Store 5 16 100 120 50 72 Example 12 Store 85 16 100 Autonomous 12 113 Example 13 Store 50 0.5 100 50 58 74 Example 14 Store 50 50 100 32 8 108 Example 15 Store 50 16 40 146 43 73 Example 16 Store 50 16 600 Autonomous 7 141

division Application form Flame Retardant Area Ratio (%) Upper thickness ratio (%) Penetration depth ratio (%) Example 1 Store 50 1.6 10 Example 2 Store 10 1.6 10 Example 3 Store 70 1.6 10 Example 4 Stripes 10 1.6 10 Example 5 Stripes 50 1.6 10 Example 6 Stripes 70 1.6 10 Example 7 Store 50 0.2 10 Example 8 Store 50 4.0 10 Example 9 Store 50 1.6 6 Example 10 Store 50 1.6 45 Comparative Example 1 Front coating 100 1.6 10 Example 11 Store 5 1.6 10 Example 12 Store 85 1.6 10 Example 13 Store 50 0.05 10 Example 14 Store 50 5.0 10 Example 15 Store 50 1.6 4 Example 16 Store 50 1.6 60

Figure 1 schematically shows the surface of the artificial leather of the present invention.

FIG. 2 schematically illustrates a cross section along line A-A 'of the artificial leather of FIG. 1.

3 to 4 schematically show the surface of the artificial leather according to another embodiment of the present invention.

Description of the Related Art [0002]

100: pre-artificial leather 200: flame retardant composition layer

a: Upper thickness b: Penetration depth

c: thickness of spare artificial leather

Claims (10)

A preliminary artificial leather comprising a nonwoven fabric made of ultrafine fibers and an elastic polymer resin impregnated in the nonwoven fabric; And Artificial leather, characterized in that it comprises a flame retardant composition layer partially coated on the preliminary artificial leather. The method of claim 1, The flame retardant composition layer is artificial leather, characterized in that partially applied in the form of dots or stripes. The method of claim 1, The artificial leather has a horizontal combustion speed of 100 mm / min or less measured under the automotive interior combustion test rule of FMVSS No. 302, and at the same time has a breathability of 20 to 50 L / min / 100 cm 2. Artificial leather. The method of claim 3, The partially applied flame retardant composition layer occupies an area of 10 to 70% of the partially applied flame retardant composition layer relative to the surface area of the preliminary artificial leather, and has an upper thickness in the range of 0.1 to 4% relative to the thickness of the preliminary artificial leather and the Artificial leather, characterized in that having a penetration depth in the range of 5 to 50% of the thickness of the pre-artificial leather. The method of claim 1, The artificial leather is characterized in that it comprises an ultrafine fiber of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate or polyamide. The method of claim 1, The flame retardant composition layer is artificial leather, characterized in that it comprises a urethane-based binder containing silicon. Manufacturing a preliminary artificial leather; And Method of producing artificial leather, characterized in that it comprises the step of partially applying a flame-retardant composition on the preliminary artificial leather. The method of claim 7, wherein The step of manufacturing the preliminary artificial leather, Preparing a nonwoven fabric; And Method of manufacturing artificial leather, characterized in that it comprises the step of impregnating an elastic polymer resin in the nonwoven fabric. The method of claim 7, wherein The step of partially applying the flame retardant composition, the method of manufacturing artificial leather, characterized in that it comprises the step of applying the flame retardant composition in the form of dots or stripes. The method of claim 7, wherein Partial coating of the flame retardant composition on the preliminary artificial leather is a manufacturing method of artificial leather, characterized in that performed using a printing method for printing, gravure coating, or a rotary screen coating method.

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