KR102821030B1 - Eco-friendly leather having plant-based materials and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an eco-friendly leather containing plant-based materials and a method for producing the same. The eco-friendly leather containing plant-based materials according to the present invention comprises a base and a coating film made of a composition containing plant-based powder and resin attached to at least one surface of the base.

Description

{ECO-FRIENDLY LEATHER HAVING PLANT-BASED MATERIALS AND MANUFACTURING METHOD THEREOF}

The present invention relates to an eco-friendly leather containing plant-based materials and a method for manufacturing the same, and more specifically, to an eco-friendly leather using plant-based powder made from plants such as apples as a leather base and a method for manufacturing the same.

In general, leather is largely divided into natural animal leather, which is recognized as a luxury product, and artificial leather, which is produced recently. Natural leather is preferred over artificial leather because it has a superior texture and is luxurious and durable. However, since it is usually made into various clothing, accessories, and daily necessities by processing the raw hide obtained by slaughtering animals, it has the disadvantages of being expensive and limited in quantity.

In addition, natural leather is a material that has been loved by people for a long time because of its tough yet soft texture, but as the social atmosphere to protect animals spreads, there is a trend of boycotting due to the aversion to using natural leather.

Due to this, the demand for synthetic leather, which is artificially manufactured to replace natural leather, is increasing, and synthetic leather is used as a material in various fields such as living materials such as bags, fashion materials such as wallets and belts, furniture upholstery materials such as sofas, wall or floor materials, medical materials, or various interior materials such as automobile interior materials. However, due to the nature of the material, the problem of environmental pollution is being raised.

In general, these artificial leathers are manufactured by impregnating a resin composition manufactured by mixing a polyurethane resin and a highly volatile organic solvent such as dimethylformamide, methyl ethyl ketone, toluene, acetone, or isopropyl alcohol onto a fabric and coating it to a certain thickness, thereby allowing it to exhibit a similar mass feel to natural leather, a soft surface feel, and improved flexibility.

In the case of artificial leather, which is manufactured for various purposes as mentioned above and comes into direct contact with human skin, it is essential to the current well-being culture that no harmful substances remain and that environmentally friendly elements are incorporated from the manufacturing process.

Recently, in order to add eco-friendly elements to the manufacturing process of artificial leather, recycled materials are often utilized, for example, apple by-products, tangerine by-products, and juice by-products are often utilized. These by-products are also called food processing by-products or agricultural by-products, and refer to intermediate products produced at the same time as the target products during food processing. These intermediate products are usually not utilized due to the difficulty of collection, separation, and processing, and are often processed as compost, landfill waste, or incineration. However, food processing products are one of the biomass resources, and have the advantage of very high added value when newly produced when recycled. In particular, they are noteworthy in that they not only have a positive impact on the domestic industry in terms of eco-friendliness, but also can improve economic efficiency and price competitiveness by increasing the productivity of the domestic food industry.

For example, Korean Patent Publication No. 10-2024-0046944 discloses an eco-friendly apple leather using apple byproducts and a method for manufacturing the same, and a method for manufacturing apple leather including the steps of preparing a nonwoven fabric, immersing the nonwoven fabric in a liquid composition containing polyurethane resin, apple powder, and essential oil, and manufacturing a nonwoven fabric impregnated with the liquid composition has been previously presented.

However, the organic solvents used to manufacture the artificial leather above have excellent solvent properties for polyurethane, but as organic chemicals, they generate a lot of pollution during the manufacturing process, which causes environmental pollution. In particular, since dimethylformamide coagulates when it comes into contact with water, workers must wipe and remove all used machinery, wastewater treatment tanks, and supply tanks one by one after work. In addition, since it easily penetrates the human body through the respiratory tract or skin and causes liver disease, kidney cancer, and skin disease, a device must be installed to recover it so that it is not released into the air as an environmentally hazardous substance. In addition, since the appearance of a product coated with dimethylformamide has a color that looks like white powder has been sprinkled on it, a process of coloring the surface using a pigment is necessary, and since the pigment also contains dimethylformamide, there are problems such as inconvenience and high processing costs.

The manufacturing process of impregnating the artificial leather fabric itself with plant-based materials inevitably requires the use of organic solvents that cause environmental pollution, and there are problems such as the complexity of the process, such as the addition of a process to express the texture of leather on the surface of the artificial leather.

Patent Document 1: Republic of Korea Publication of Patent Publication No. 10-2024-0046944

The present invention is intended to solve the above problems, and by manufacturing a coating film made of a composition including plant-based powder on an eco-friendly leather base, environmental pollution is reduced and eco-friendly leather using easily recycled plant-based materials can be manufactured.

In addition, when manufacturing the coating film, a desired pattern can be easily manufactured by applying a composition containing plant powder and resin onto a release paper containing a specific pattern.

The present invention provides an eco-friendly leather including a plant-based material, which includes a base and a coating film made of a composition including plant-based powder and resin attached to at least one surface of the base, in order to solve the above-mentioned problem.

In addition, the present invention can provide an eco-friendly leather in which the base is a non-woven fabric or a fiber sheet.

In addition, the present invention can provide an eco-friendly leather in which the base includes a recycled plastic material.

In addition, the present invention can provide an eco-friendly leather manufactured by impregnating the base with a composition containing plant-based powder and resin.

In addition, the present invention can provide an eco-friendly leather in which the plant-based powder is at least one selected from the group consisting of apples, pears, persimmons, tangerines, pineapples, and cacti.

In addition, the present invention can provide an eco-friendly leather in which the resin is a polyurethane resin.

In addition, the present invention can provide an eco-friendly leather in which the vegetable powder and resin are mixed in a weight ratio of 1:2 to 1:6 to produce a coating film.

In addition, the present invention can provide eco-friendly leather in which the plant-based powder has a particle diameter of 10 um to 500 um.

In addition, the present invention can provide eco-friendly leather having a moisture content of 2 to 5% using the plant-based powder.

In addition, the present invention can provide an eco-friendly leather, wherein the composition includes at least one dispersant selected from the group consisting of a soda-based inorganic dispersant, a silicon dispersant, and an acrylic dispersant for dispersing the plant-based powder.

In addition, the present invention can provide eco-friendly leather having a tensile strength of 500 N/5 cm or more and a tear strength of 10 N or more.

The eco-friendly leather according to the present invention can be easily manufactured as eco-friendly leather including a coating film utilizing recycled plant-based materials, and thus has the effect of reducing environmental pollution.

In addition, when manufacturing a coating film, there is an effect that allows for easy manufacturing of a desired pattern by applying a composition containing plant-based powder and resin onto a release paper containing a specific pattern.

The attached drawings are intended to explain the contents of the present invention in more detail to a person skilled in the art, but the technical idea of the present invention is not limited thereto.
Figure 1 is a cross-sectional view illustrating eco-friendly leather according to one embodiment of the present invention.
FIG. 2 is a photograph of a coating paper showing a urethane coating film formed on a release paper to manufacture a coating film according to one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are presented to sufficiently convey the idea of the present invention to those skilled in the art to which the present invention pertains. The present invention is not limited to the embodiments presented herein and may be embodied in other forms. In order to clarify the present invention, the drawings may omit parts that are not related to the description, and may somewhat exaggerate the sizes of components to help understanding.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present invention. Also, the singular forms used herein include the plural forms as well, unless the context clearly dictates otherwise. Also, the meaning of "comprises" or "containing" as used herein specifies a particular feature, region, integer, step, operation, element, or component, but does not exclude the addition of other particular features, regions, integers, steps, operations, elements, or components.

In the present invention, the terms first, second, etc. are used to describe various components, and the terms are used only for the purpose of distinguishing one component from another.

In addition, the terminology used herein is only used to describe exemplary embodiments, and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. It should be understood that the terms "comprises," "includes," or "has" in this specification are intended to specify the presence of implemented features, numbers, steps, components, or combinations thereof, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, components, or combinations thereof.

The present invention may have various modifications and may take various forms, and thus specific embodiments are illustrated and described in detail below. However, this is not intended to limit the present invention to specific disclosed forms, but should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

Fig. 1 is a cross-sectional view illustrating an eco-friendly leather according to one embodiment of the present invention. Fig. 2 is a photograph of a coated paper showing a urethane coating film formed on a release paper for manufacturing a coating film according to one embodiment of the present invention.

Referring to Figure 1, the eco-friendly leather and its manufacturing method according to the present invention will be described in detail below.

Referring to FIG. 1, the eco-friendly leather of the present invention includes a base (100) and a coating film (200) attached to at least one surface of the base (100).

The above base may be a non-woven fabric or a fiber sheet.

The above nonwoven fabric may be a fiber containing polyester or polypropylene.

For example, the nonwoven fabric may use a sea-island type ultrafine fiber or a general nonwoven fabric. For example, the nonwoven fabric may be manufactured using a sea-island type composite fiber including polyethylene terephthalate (PET) and an alkali-soluble copolymerized polyester, and when the nonwoven fabric made of the sea-island type composite fiber is later immersed in an alkaline aqueous solution, the alkali-soluble copolymerized polyester dissolves to form multiple holes in the thin yarn cross-section, thereby forming ultrafine fibers. Specifically, the nonwoven fabric may be manufactured using a sea-island type filament manufactured by composite spinning using polyethylene terephthalate and an alkali-soluble copolymerized polyester as raw materials.

The above fiber sheet may be manufactured by spinning and weaving fibers including polyester or polypropylene.

The above base may include a plastic recycled material, for example, a material utilizing polyester recycled from waste PET bottles or waste synthetic fibers.

The eco-friendly leather of the present invention includes a coating film (200) attached to at least one surface of the base (100).

The above coating film (200) is manufactured from a composition containing plant-based powder and resin.

The above plant-based powder may be, but is not limited to, one or more selected from the group consisting of apples, pears, persimmons, tangerines, pineapples, and cactus.

The above plant-based powder may be made from various parts of the plants, such as leaves, stems, roots, fruits, peels, and whole plants, and it may be preferable to use parts of the fruits other than the pulp, if possible.

The above plant-based powder refers to powder obtained from plants, and specifically,

The above plants are not limited to these, but plants such as apples, pears, persimmons, tangerines, pineapples, or cacti can be utilized, and apple by-products, tangerine by-products, juice by-products, etc. can be utilized. These by-products are also called food processing by-products or agricultural by-products.

By-products of these plants can be the peels of fruits from which the flesh has been removed, the residue remaining after juicing the fruits, and the powder obtained by drying and crushing these.

At this time, the plant by-product can be hot-air dried at a temperature range of 50 to 80°C for 6 to 18 hours. If dried at a temperature below 50°C for less than 6 hours, the plant by-product may not be sufficiently dried, causing the moisture content of the plant powder to be high, resulting in rotting. If dried at a temperature exceeding 80°C for more than 18 hours, the plant powder may burn or have almost no moisture content, making it difficult to mix with the resin.

The above plant-based powder may have a particle diameter of 10 um to 500 um, and for example, it is preferable that the plant-based powder have a particle diameter of 100 to 200 um.

If the particle diameter of the above plant powder is less than 10 um, the plant powder clumps depending on the moisture content, so that the dispersibility with the resin is reduced and mixing is not performed well, and thus, there is a problem that the coating film bursts due to the powder clumping when applying the composition. If the particle diameter of the plant powder exceeds 500 um, the powder particle size is too large, making it difficult to increase the content of the plant powder, and when forming the coating film, the particles get caught on the coating bar, causing the coating to appear uneven, thereby reducing the workability.

The particle diameter of the above plant-based powder can be controlled by mechanically milling the dried powder, and the milling method is not particularly limited and may be performed by various methods, such as a ball mill, an airjet mill, a bead mill, a roll mill, a planetary mill, a hand mill, a high energy ball mill, a planetary mill, a ball mill, a stirred ball mill, a vibrating mill, a mechanofusion milling, a shaker milling, a planetary milling, an attritor milling, a disk milling, a shape milling, a nauta milling, a nobilta milling, a high speed mix, etc.

The above vegetable powder may have a moisture content of 2 to 5%.

If the moisture content of the above plant powder is less than 2%, there is a problem of reduced compatibility with the resin, and if the moisture content exceeds 5%, there is a problem of high moisture content of the plant powder, resulting in spoilage during storage of materials, etc.

The above plant-based powder and resin can be mixed in a weight ratio of 1:2 to 1:6 to produce a coating film.

When the weight ratio of the plant-based powder and resin is less than 1:2, the content of the plant-based powder is too high, which may cause the coating film to burst when forming the coating film, and there is a problem that workability deteriorates during the coating process due to an increase in viscosity as the powder content increases. When the weight ratio exceeds 1:6, the content of the plant-based powder is too low, which makes the effect of adding the plant-based powder insignificant, and fails to meet the biocarbon content standard for receiving the United States Department of Agriculture's biomaterial-based eco-friendly certification (USDA).

Additionally, for example, the plant-based powder may be included in the composition at 15 to 50 wt%, preferably at 20 to 30 wt%.

The above resin is not limited thereto, but may be, for example, a polyurethane resin.

For example, the above polyurethane resin can be manufactured using a polyether type PTMG (molecular weight 1,000 to 2,000), a diol (1,4-butandiol, 1,6 hexandiol, etc.), MDI (methylene diphenyl diisocyanate, 4,4'-diphenylmethane diisocyanate) as a base isocyanate, and DMF ([dimethylformamide)) as a solvent.

Here, the polyurethane resin may be a recycled polyurethane resin, and for example, a recycled thermoplastic polyurethane (TPU) resin may be used.

In another embodiment of the present invention, the eco-friendly leather of the present invention includes a base (100), and the base (100) may be manufactured by impregnating a composition including plant-based powder and resin.

This is in accordance with the method of impregnating a composition into a nonwoven fabric in order to contain apple powder in eco-friendly apple leather manufactured according to the conventional patent document 1. In the present invention, in order to increase the content of plant-based materials with respect to the total content of eco-friendly leather, a composition including plant-based powder can be additionally impregnated into the base (100) which is the fabric.

The composition may contain at least one dispersant selected from the group consisting of a soda-based inorganic dispersant, a silicone dispersant, and an acrylic dispersant for dispersing the plant-based powder. For example, the dispersant may be an acrylic wetting dispersant such as DISPERBYK-2015 or BYK-154.

The dispersant is included in the composition for producing the coating film to disperse the plant-based powder well in the resin, and may be included in an amount of 0.5 to 3 wt% based on the total weight of the composition.

The above composition may further include a natural oil as an additional ingredient, and the natural oil, as a natural ingredient, provides a refreshing fragrance, thereby calming the mind and body and relieving stress when not only workers during the process but also consumers inhale the fragrance through their nose.

In addition, the natural oil may be added to complement the stiff feel of eco-friendly leather, and by complementing the stiff feel of eco-friendly leather and imparting a soft touch and gloss, it is possible to realize gloss and feel comparable to natural leather.

For example, the natural oil may be citrus oil, cinnamon oil, eucalyptus oil, lavender oil, pine oil, lemon oil, fragrance oil, or combinations thereof.

For example, the natural oil may be included in an amount of 0.1 to 5 wt% based on the total weight of the composition. If the natural oil is included in an amount of less than 0.1 wt%, the flexibility, touch, gloss, fragrance, etc. that are exhibited by including the natural oil may not be sufficiently exhibited, and if it exceeds 5 wt%, the mixing properties with other ingredients may be impaired.

For example, the composition may additionally include a natural water-repellent agent. Conventionally, artificial leather manufactured using polyurethane resin has weak physical properties, so it easily becomes fluffy and may have appearance defects such as deformation. In particular, when used in a humid environment, such appearance defects may occur frequently, and mold may also occur. Accordingly, the composition may additionally include a natural water-repellent agent, which is a substance having water-repellent and waterproofing properties that can be easily obtained from nature, thereby imparting water-repellent properties to the eco-friendly leather manufactured, thereby improving the storage and usability of apple leather.

For example, the natural water repellent may include one selected from the group consisting of palm oil extracted from the endosperm of the coconut fruit, olive oil, pistachio oil, peanut oil, lard, tallow, beef tallow or combinations thereof.

For example, the natural water repellent may be included in an amount of 0.01 to 3 wt% based on the total weight of the composition. If the natural water repellent is included in an amount of less than 0.01 wt%, the water repellent effect exhibited by including the natural water repellent may not be sufficiently exerted, and if it exceeds 3 wt%, the mixing property with other components may be impaired.

The above coating film (200) can be formed by coating the composition on a release paper to form a film, and then forming a coating film on one surface of the base (100) through a heat-compression process.

During the process of coating the above coating film (200) on a release paper, there is an advantage in that a desired pattern can be easily formed on leather fabric by coating the coating film (200) with a specific pattern engraved thereon by coating it on a release paper containing a specific pattern and coating it on the base (100).

Eco-friendly leather according to one embodiment of the present invention has a tensile strength of 500 N/5 cm or more according to ISO 1421 and a tear strength of 10 N or more according to ISO 4674-1, which can exhibit strength equivalent to that of general natural leather and strength superior to that of existing artificial leather, and can provide sufficient strength to be applied not only to leather products such as bags and wallets, but also to products such as shoes and safety shoes that require very high strength.

Example

Example 1

A base of 1.2 mm thick non-woven fabric made of recycled PET waste plastic was prepared, and a composition was prepared by mixing 37 wt% of apple powder with a diameter of 200 μm (D50) and a moisture content of 3% as plant-based powder, 60 wt% of polyurethane resin as resin, and 3 wt% of DISPERBYK-2015 as a dispersant. This was coated on a release paper to form a film with a thickness of 0.1 mm, as shown in Fig. 2.

Afterwards, a coating film was formed by thermal compression bonding the above-mentioned film to the above-mentioned base to manufacture leather fabric.

Example 2

A leather fabric was manufactured in the same manner as in Example 1, except that 25 wt% of the apple peel powder and 77 wt% of the polyurethane resin were applied.

Example 3

A leather fabric was manufactured in the same manner as in Example 1, except that tangerine peel powder was used instead of the apple powder.

Example 4

A leather fabric was manufactured in the same manner as in Example 1, except that pineapple leaves were used instead of the apple powder.

Example 5

A leather fabric was manufactured in the same manner as in Example 1, except that cactus peel was included instead of the apple powder.

Comparative Example 1

A leather fabric was manufactured in the same manner as in Example 1, except that 55 wt% of the apple peel powder and 42 wt% of the polyurethane resin were applied.

Comparative Example 2

A leather fabric was manufactured in the same manner as in Example 1, except that 15 wt% of the apple peel powder and 82 wt% of the polyurethane resin were applied.

Comparative Example 3

A leather fabric was manufactured in the same manner as in Example 1, except that the moisture content of the apple peel powder was applied at 0.5%.

Comparative Example 4

A leather fabric was manufactured in the same manner as in Example 1, except that the moisture content of the apple peel powder was set to 7%.

The leather fabrics manufactured according to Examples 1 to 5 and Comparative Examples 1 to 4 were measured for ISO 1421 (tensile strength, elongation), ISO 4674-1 (tear strength), and ISO 12947-2 (abrasion strength), and the results are shown in Table 1 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Tensile strength (along; axial, N/5cm) 650 630 590 620 570 420 370 350 440 Tensile strength (across; transverse, N/5cm) 680 710 630 650 620 530 510 480 520 Elongation (along; axial, %) 19 21 23 17 19 13 14 17 15 Elongation (across; transverse, %) 22 24 24 21 23 17 18 24 21 Tear strength (along; axial, N) 18 20 13 17 16 8 7 8 12 Tear strength (across; transverse, N) 24 26 22 21 24 17 18 19 22 Abrasion strength (abrasion, cycles (12Kpa)) 65,000 70,000 62,000 67,000 64,000 48,000 58,000 57,000 58,000

Referring to the above examples and comparative examples, it was found that the eco-friendly leather according to one embodiment of the present invention has a tensile strength of 500 N/5 cm or more in both the axial and transverse directions according to ISO 1421, an elongation of 15% or more in both the axial and transverse directions, and a tear strength of 10 N or more in both the axial and transverse directions according to ISO 4674-1. This means that the eco-friendly leather according to the configuration and composition of one embodiment of the present invention can exhibit strength equivalent to or similar to that of general natural leather, and strength superior to that of existing artificial leather, and can provide sufficient strength that can be applied not only to leather products such as bags and wallets, but also to products such as shoes and safety shoes that require very high strength.

The above description of the present invention is for illustrative purposes only, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single component may be implemented in a distributed manner, and likewise, components described as distributed may be implemented in a combined manner.

The scope of the present application is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present application.

100: Base 200: Coating Film
210: Vegetable Powder

Claims (11)

Base; and
A coating film made of a composition comprising a plant-based powder and a resin having a particle diameter of 10 μm to 200 μm and a moisture content of 2 to 5%, which is attached to at least one surface of the base,
The above coating film is formed by coating the composition on a release paper to form a film, and then forming a coating film on one side of the base through a heat-compression process.
Eco-friendly leather containing plant-based materials having a tensile strength of 500 N/5 cm or more in both the axial and transverse directions, an elongation of 17% or more in both the axial and transverse directions, and a tear strength of 13 N or more in both the axial and transverse directions. In the first paragraph,
The above base is eco-friendly leather, which is a non-woven fabric or fiber sheet. In the first paragraph,
The above base is made of eco-friendly leather containing recycled plastic materials. In the first paragraph,
The above base is an eco-friendly leather manufactured by impregnating a composition containing plant-based powder and resin. In the first paragraph,
The above plant-based powder is an eco-friendly leather, which is at least one selected from the group consisting of apples, pears, persimmons, tangerines, pineapples, and cacti. In the first paragraph,
The above resin is an eco-friendly leather made of polyurethane resin. In the first paragraph,
An environmentally friendly leather in which the above vegetable powder and resin are mixed in a weight ratio of 1:2 to 1:6 to produce a coating film. delete delete In the first paragraph,
The above composition is an eco-friendly leather containing at least one dispersant selected from the group consisting of a soda-based inorganic dispersant, a silicone dispersant, and an acrylic dispersant for dispersing the plant-based powder. delete