TWI382924B - Pet reinforced composite, manufacturing method thereof and application thereof - Google Patents

Description

All-polyester self-reinforced composite material, manufacturing method and application thereof

The present invention is a composite material, and more particularly to a composite material of all-polyester, a process for its preparation, and its use.

Traditional composite materials have the characteristics of light weight and high strength, so they are the best choice for many special needs. However, current composite materials are limited by price, unrecoverable, mostly thermosetting materials, and poor composite interface properties of heterogeneous materials, which limits their application.

Pegoretti (2007), a composite material expert, puts forward in the future trend of composite materials that the era of environmental protection and energy conservation has come, and the development of materials recycling and reuse methods should have updated thinking and practices, while single polymer composite (Single Polymer Composite, Referred to as SPC) is a very important and special material in this trend.

SPC refers to a composite material in which a reinforcing material (Reinforcement) and a continuous phase substrate (Matrix) are the same chemical composition of a polymer material, and SPC has considerable advantages and features. For example, since the reinforcing material has the same chemical structure as the substrate, the two are completely compatible, there is no interface problem of the conventional fiber composite, and the high orientation of the molecular chain of the fiber material in the SPC composite makes the material sufficient. The initial strength gives the SPC superior stiffness, specific strength, low density, etc., especially for impact toughness and elongation at break. In addition, the waste/edge material in the manufacturing process of the thermoplastic single polymer or after the end of the product life cycle can be completely recovered by the melting method, so that the single polymer composite material fully meets the requirements of the green material.

At present, the development of SPC, which is relatively mature in the industry, is mainly based on the manufacturer of Propylene Fabrics Inc. and other SPC products based on polypropylene (PP). PP-SPC's reinforcement (fiber) and continuous phase substrate (resin) are all PP, so it solves all the problems caused by the heterogeneity of fiber and substrate in traditional composite materials, not only has the advantage of relatively low cost, but also It allows PP-SPC to have the characteristics of post-processing.

However, the aforementioned all-polypropylene composite (PP-SPC) has many shortcomings that still need to be improved, such as the following:

1. Mechanical properties are still not strong enough, and also affected by temperature, resulting in a significant decline in performance.

2. The melting point temperature is low and the temperature resistance is insufficient, resulting in limited use.

3. Polypropylene is a non-polar substance, and its surface is not stable enough to react with other substances. An overly stable surface is not conducive to the bonding (gluing, bonding) or surface coating of a polypropylene polymer sheet with other materials, thus causing the disadvantage of being difficult to process.

In order to solve the many shortcomings of the prior art, the present invention proposes that the whole polyester is used as the main component of the single polymer composite material, and solves the technical problem that the mechanical properties of the conventional technology are poor, the melting point is too low, and the post-processing is not easy.

In order to solve the above technical problems, the present invention provides a method for manufacturing a wholly polyester composite material, the method comprising: subjecting a polyester fiber cloth to a heat setting process; modifying a polyester resin to lower the melting point and forming a film shape. And modifying the difference between the melting point of the polyester resin and the polyester fiber cloth to form a working temperature window; and superimposing the polyester fiber cloth and the modified polyester resin, and in the working temperature window The polyester fiber cloth and the modified polyester resin are formed into a single-layered all-polyester composite material by a hot pressing process.

The invention further provides a single-layered all-polyester composite material comprising a polyester fiber cloth and a low-melting-point polyester resin which is tightly coated with a film of the polyester fiber cloth, and the melting point of the low-low melting point polyester resin The method for manufacturing the single-layer polyester composite material comprises: heat-setting the polyester fiber cloth; modifying a polyester resin to lower the melting point and forming a film shape. The low melting point polyester resin, the modified melting point of the low melting point polyester resin and the polyester fiber cloth form a working temperature window; and the polyester fiber cloth and the low melting point polyester resin are laminated The polyester fiber cloth is combined with the low melting point polyester resin in a working temperature window to form the single layer full polyester composite material.

The invention further provides a method for manufacturing a continuous all-polyester composite material, comprising the steps of: forming a continuous polyester resin film by modifying a polyester resin to form the polyester resin film with a polyester resin film; The difference in melting point of the continuous polyester fiber cloth forms an operating temperature interval; the polyester resin film is laminated with the polyester fiber cloth by hot rolling to form a continuous all-polyester composite material. The sheet; the continuous all-polyester composite sheet is subjected to a cooling means and then wound to complete the continuous all-polyester composite sheet.

The present invention further provides a full polyester product having a curved surface, which is composed of a layer of a plurality of polyester fiber cloths laminated on each other and laminated with a low melting point polyester resin, wherein the full-poly layer having the flexible surface is formed. The step of manufacturing the ester product comprises: subjecting each of the polyester fiber cloths to a heat setting process; modifying a polyester resin to lower the melting point and forming a film-like low melting point polyester resin, the low after the modification The difference between the melting point of the polyester resin and the melting point of the polyester fiber cloth forms a working temperature window; interlacing more than one layer of the polyester fiber cloth with one or more layers of the low melting point polyester resin, and one in the working temperature window The hot press process combines the polyester fiber cloth with the low melting point polyester resin to form the single layer full polyester composite material; stacking multiple layers of single layer full polyester composite material and adding high temperature to make each single layer full polyester complex The low melting point polyester resin forms a flow and then applies a high pressure combined with each single layer of the full polyester composite material to form a laminated all-polyester composite sheet; the laminated all-polyester composite sheet is formed by hot stamping into a full polyester product with a flexible surface

Therefore, the single polymer composite material of the whole polyester (PET) proposed by the invention is not found in the prior art, and the advantages of a plurality of different composite materials or homogeneous materials are further gathered as follows:

1. Compared with the conventional PP single polymer composite material, the whole polyester (PET) single polymer composite material of the invention has the advantages of relatively low cost, recyclability, good mechanical properties, heat resistance and wide application range, and is easy to be combined with other materials. The combination of materials makes it easy to process and simplifies product manufacturing difficulties.

2. The all-polyester self-reinforcing composite material of the present invention has the thermoplastic characteristics not possessed by the conventional composite material, and the invention can be heated and formed after forming, and thus has high processing flexibility.

Please refer to the first figure, which is a process step of the all-polyester self-reinforcing composite material of the present invention comprising: step 1. fiber cloth and resin preparation (10): the raw material of the all-polyester composite material of the invention comprises agglomeration Ester fiber cloth and a polyester resin, wherein:

(1) The polyester fiber cloth must first undergo a heat setting step to maintain dimensional uniformity in the subsequent manufacturing process requiring heating, in other words, after the selected polyester fiber cloth is subjected to a heat setting step at a specific temperature. The polyester fiber cloth can maintain a stable and variable size range in the temperature rising and cooling process;

(2) The polyester resin must first be modified to lower the melting point of the polyester resin, thereby causing a temperature difference (about 10 to 60 degrees) between the selected polyester resin and the melting point of the polyester fiber cloth. Form a working temperature window. The modification method of the polyester resin is not limited, and different modification methods such as copolymerization, addition of materials having different molecular weights, and the like can be selected depending on the demand. In this embodiment, the melting point of the polyester resin is lowered by means of copolymerization, so that the polyester resin and the polyester fiber cloth produce a temperature difference of the operating temperature window. Wherein, the main purpose of forming the working temperature window is to avoid the polyester resin in the high-temperature molten state caused by the polyester resin in the process of manufacturing the all-polyester self-reinforced composite material, or the molecular structure is destroyed. Since it has good mechanical properties, it is necessary to form the polyester fiber cloth and the polyester resin to have different molten state forming temperatures as a process space for producing the all-polyester self-reinforced composite material of the preferred embodiment. If the temperature difference between the polyester fiber cloth and the polyester resin is greater (the operating temperature window temperature is larger), the elasticity of the manufacturing process of the all-polyester self-reinforced composite material is greater, and The structural stability of the polyester fiber cloth is better.

Supplementary explanation The copolymerization method used in the foregoing embodiment is as follows. In the process the polymer melt, generally exhibit a broad melting temperature range, i.e., there is a "melting threshold"; typically the final temperature at which the melting point is completely melted called T _m. In general, polyester (polyethylene terephthalate, polyethylene terephthalate (PET)) has a melting point of about 255 ° C ~ 265 ° C, but in order to make the whole polyester self-reinforced in this example In the composite process, the melting point of the substrate and the reinforcing material is differentiated, so the PET substrate used must be modified to obtain a lower melting point PET. The melting point of a material is usually affected by: (i) the influence of the molecular structure on the melting point, including the intermolecular forces, the rigidity of the molecular chain, the symmetry and integrity of the molecular chain; (ii) the crystallization condition versus the melting point. The effect includes the relationship between the thickness of the wafer and the melting point, and the relationship between the crystallization temperature and the melting point. Other methods which affect the melting point of the polymer and are often used to change the melting point in practice include molecular weight change, monomer copolymerization or small molecular polymer addition, and addition of a plasticizer, wherein the copolymerization method is effective.

The copolymer method is used to change the melting point of the polyester, usually adding adipic acid, sebacic acid, polyethylene glycol, polypropylene glycol, butanediol, isophthalic acid (IPA), ethylene glycol adipate (DEA). )...etc. [Zheng Wei et al., Master Thesis, Institute of Materials Science, National Sun Yat-sen University, 2001], which is the most effective example of IPA and DEA melting point improvement. Adding 7.5mol%, 15mol%, and 25mol% IPA, respectively, can lower the melting point from 252°C of pure PET to 233°C, 214°C and 186°C, respectively. If the ratio of DEA is 5.5mol%, 15mol%, 21mol% , the melting point can be reduced from 252 ° C of pure PET to 233 ° C, 219 ° C and 185 ° C [Tang Shi, Beijing Institute of Fashion Master's Thesis, 2003].

The effect of additives on the melting point is slightly different for various materials. If inorganic particles such as cerium oxide (SiO ₂ ) or titanium dioxide (TiO ₂ ) are added to PET, the inorganic particles can destroy the regularity of the arrangement of the polyester molecules, but different. The inorganic particles have different effects on the nucleation and crystallization of the melt, and some play a hindrance role, and some promote the effect. The end point depends on the amount of addition, and the melting point decreases with the increase of the inorganic component content [Ma Liuqiang, 21, 5, Synthesis Technology and Applications, 2006].

In addition, the addition of a plasticizer is to add a compatible low molecular weight plasticizer or solvent to the polymer. The polymer molecules can attract these low molecular substances to produce a more irregular structure, in order to lower the melting point. Plasticizers such as glycerol, arsenic trioxide, sodium citrate, etc., but because of the poor thermal stability of the plasticizer during the mixing process, it is easy to dissipate due to volatilization or cracking due to high temperature, thus changing the temperature The quality effect is not stable.

The blending method refers to the physical modification of the polyester, that is, the addition of an auxiliary agent or other components to the polyester substrate, and the addition of a low molecular auxiliary or a low molecular weight oligomer to the PET melt also causes the melting point of the PET. reduce. For example, in a polyester melt, a low molecular flame retardant or a flame retardant system is added, and the melting point of the polyester is generally lowered by 10 ° C to 20 ° C [Luo Hailin, Zhejiang University of Technology, Master's thesis, 2005], which is due to low molecular weight additives and PET. After the melt is uniformly mixed and quenched by chilling, the segment is frozen to make it amorphous. When the temperature is slowly raised to the glass transition temperature (Tg), the chain begins to move, and the molecular chain near the crystallization temperature will enter the crystal lattice. Due to the presence of low molecular substances, the lattice defects are increased, the crystallization is imperfect, and the melting point of PET is lowered. Blending methods Currently, more research is on the melting point of PET/PBT blends. In a compatible polymer melt, if one of the components is capable of crystallizing, the phenomenon of a decrease in melting point can be observed. PBT is a homologue of PET. The two are identical in amorphous form. They are crystalline linear saturated polyester. The molecular chain of PBT is more than two methylene groups than PET. Its melting point and glass transition temperature are lower than PET, so PBT molecule The segment activity is stronger than PET, and its crystallization rate is 10 times faster than PET.

As described above, there are many ways to reduce the polyester base material or the resin. The working temperature window can be formed by the temperature range in which the polyester base material and the polyester fiber have a melting point as described above. The modified PET resin used in this embodiment is modified by copolymerization to obtain a PET copolymer, and the original melting point is lowered from 265 ° C of the general PET resin to 198.07 ° C of the modified PET resin used, and the modification is carried out. Post PET was used as the resin substrate of this example. The second figure shows the characteristics of the modified polyester resin, showing that the modified polyester resin can have a melting point of about 200 degrees, and its flow temperature can be lowered to a low viscosity of 100 Pa ‧ at 220 ° C.

(3) After the polyester resin is modified to lower the melting point, the modified polyester resin is formed into a sheet shape. The molding may be carried out by heating the polyester resin in a flowing state, and then cooling it after being placed on a mold or a machine platform to form a sheet-like polyester resin as the polyester substrate of the present embodiment.

Step 2. Stacking and hot pressing to form a single layer of all-polyester composite (20)

After laminating more than one sheet of the polyester resin with more than one heat-set polyester fiber cloth, the polyester resin is flowed into a flowing state by a hot pressing method under a hot pressing method to promote the flow of the polyester resin into the polyester resin. A single layer of all-polyester composite material is formed in the mesh pores between the polyester fiber cloths.

Step 3. Lamination (30)

After laminating a plurality of single-layered all-polyester composite materials, the polyester resin of the single-layered all-polyester composite material of each layer is flowed by the above-mentioned hot pressing method, and is subjected to hot pressing to cool down to form a laminated layer. Polyester composite sheet.

Step 4. Product Manufacturing (40)

In accordance with the specifications of the manufactured product, it is possible to select a laminated all-polyester composite sheet having a suitable thickness and number of layers to be formed by a hot stamping method to obtain a full-polyester finished product.

Product application development examples, such as special function hard soles, use the light and strong properties of all-polyester self-reinforced composite materials to replace the currently used glass fiber composite materials, in addition to providing this function shoes with rigid sole support function, More importantly, the use of low-density polyester fibers instead of high-density glass fibers can achieve weight reduction. In addition, the rapid and simple processing characteristics of thermoplastic composites can help improve the production efficiency of this product; The finished product is simple and thin, and is similar to a flat plate. Therefore, it is possible to directly form a film by a raw material and stack it into a mold.

Compared to the current commercial full PP self-reinforced materials such as Curv In this embodiment, the sole material made of the all-polyester self-reinforced composite material has excellent heterogeneous bonding compatibility, so that it is more convenient for the manufacturer to perform post-processing, which greatly simplifies the process and manufacturing cost. Since the sole material needs to be bonded to other shoe materials to combine a complete sole, the non-polar PP material has poor surface adhesion, which often leads to adhesive failure, and even degumming occurs when the sole is shot. In the present embodiment, the all-polyester self-reinforced composite material has excellent heterogeneous adhesion characteristics due to the polarity of the surface, and can effectively overcome the problem of processing adhesion.

In the control of process temperature and time, as shown in the first figure, the hot-pressing of the polyester fiber cloth and the hot-press forming of the single-layered all-polyester composite material are carried out in a relatively high-temperature and short-time manner, for example. In other words, the selected material is given a working temperature window between 210 and 235 ° C, and the temperature and time for heat setting can be set at 235 ° C for 1 min.

Compared with the hot press forming of the polyester fiber cloth heat setting and the single layer full polyester composite material, the temperature and time parameters required for the lamination step are relatively low temperature and long time, for example, 215 ° C, 2-6 min. In the manufacturing process of the product, since it is only required to soften the polyester resin of the laminated all-polyester composite material, the required processing temperature is the lowest, about 150 to 200 °C. The aforementioned temperature and time parameters may be slightly changed in accordance with the selection of polyester fiber cloth and polyester resin of different characteristics.

In terms of results, the mechanical property measurement results of the various laminated all-polyester composite sheets completed in accordance with the foregoing steps are as shown in Table 1. The results show that the composite material provided by the present embodiment has excellent mechanical properties compared with the homogeneous polyester sheet, and the tensile, bending and impact resistance properties thereof are all significantly improved, and the impact strength can be improved up to 647.5 J/ Above m, the purity of pure PET (homogeneous PET) is up to 60 times.

In addition, in this embodiment, a PET fiber cloth is used, and the PET fiber cloth can be selected as a material source for recycling, so that the material cost can be further saved and the environmental protection effect can be achieved. In addition, the combination of PET and PET fiber is recovered, one is a material whose performance is degraded, the thermal performance is poor, and the flow is fast, and the other is a high-situ extended, highly crystalline material, and the PET material of this embodiment is differentiated. The combination provides an effective, wider processing window that is more conducive to manufacturing convenience.

Further, the sheet-like polyester resin can be produced not only by the prior art, but also by a slight improvement in a continuously production form. As shown in the third figure, the copolymerized modified polyester resin is first formed into a continuous polyester resin film (51), and the polyester resin film (51) is continuously continuous with a hot rolling method. The polyester fiber cloth (52) is laminated and combined with hot melt pressing, wherein the so-called hot rolling method is to fold the polyester resin film (51) and the polyester fiber cloth (52) together into one heating. In the roller group (60), the high temperature and high pressure of the heating roller group (60) first melt the polyester resin film (51) into a melt flow and then extrude into the polyester fiber cloth (52) to form a continuous type. The output of the all-polyester composite sheet. The continuous all-polyester composite sheet outputted by the hot-pressing roller set (60) is subjected to a cooling means (70), and is continuously wound up by a receiving reel (80) to complete the pressed all-polyester composite material. Sheet. The cooling means (70) may be a cold air generating device, a nitrogen cooling device, or the like. Therefore, with the process proposed in the present embodiment, the all-polyester composite material can achieve mass and rapid mass production, breaking the limitation of mass production of the conventional technology.

(51). . . Polyester resin film

(52). . . Polyester cloth

(60). . . Heating roller set

(70). . . Cooling means

(80). . . Receipt

The first figure is a schematic flow chart of a preferred embodiment of the present invention.

The second figure is a graph showing the viscosity characteristics of the copolymerized polyester resin of the preferred embodiment of the present invention.

The third figure is a schematic diagram of a continuous production process of a preferred embodiment of the present invention.

Claims (27)

A method for manufacturing an all-polyester composite material, comprising the steps of: subjecting a polyester fiber cloth to a heat setting process; modifying a polyester resin to lower the melting point and forming a film shape, and modifying the modified polyester resin Forming a working temperature window with a difference in melting point of the polyester fiber cloth; and laminating the polyester fiber cloth and the modified polyester resin, and drying the polyester fiber cloth in a hot pressing process in the working temperature window The modified polyester resin is formed into a single-layered all-polyester composite. The method for producing an all-polyester composite material according to claim 1, after the single-layer polyester composite material is formed, after laminating two or more layers of the single-layer polyester composite material, the single temperature is increased. The layer of polyester composite material causes the polyester resin to be in a flowing state, and two or more layers of the single-layer polyester composite material are laminated and bonded into a laminated all-polyester composite material sheet under high pressure. The method for manufacturing a full-polyester composite material according to claim 2, after the laminated polyester composite material sheet is completed, the laminated polyester composite material sheet is subjected to a hot stamping method to reconstitute the laminated polyester. The sheet material forms a finished product of a full polyester composite having a flexible surface. The method for manufacturing a full-polyester composite material according to claim 1, after the single-layered all-polyester composite material is completed, the single-layered all-polyester composite material is formed into a flexible surface by a hot stamping method. A full polyester composite finished product. The method for producing a full-polyester composite material according to any one of claims 1 to 4, wherein the method for modifying the melting point of the polyester resin comprises copolymerization, addition of an inorganic material, addition of a low molecular material or blending Polymer Materials. The method for producing a wholly-polyester composite material as described in claim 5, wherein the operating temperature window ranges from 10 to 60 degrees. The method for producing a wholly-polyester composite material as described in claim 5, wherein the temperature and time of the heat setting process are 235 ° C and 1 min, respectively. The method for producing a wholly polyester composite material as described in claim 2, wherein the temperature and time of the hot stamping method are 215 ° C and 2-6 min. The method for producing a wholly polyester composite material according to claim 5, wherein the copolymerization method is the polyester resin and is selected from the group consisting of adipic acid, sebacic acid, polyethylene glycol, polypropylene glycol, and dibutyl A group consisting of alcohol, isophthalic acid and ethylene adipate is copolymerized. The invention relates to a single-layered all-polyester composite material comprising a polyester fiber cloth and a low-melting-point polyester resin which is tightly coated with a film-like shape of the polyester fiber cloth, and the low-low melting point polyester resin has a melting point lower than the polycondensation An ester fiber cloth, wherein the step of manufacturing the single-layer polyester composite material comprises: subjecting the polyester fiber cloth to a heat setting process; modifying a polyester resin to lower the melting point and forming a film-like low melting point poly An ester resin, the modified melting point of the low melting point polyester resin and the polyester fiber cloth form a working temperature window; and the polyester fiber cloth and the low melting point polyester resin are laminated, and the working temperature window is The polyester fiber cloth is combined with the low melting point polyester resin by a hot pressing process to form the single layer full polyester composite material. The single-layered all-polyester composite material according to claim 10, wherein the polyester fiber cloth is a fiber cloth woven from recycled polyester. The operating temperature window ranges from 10 to 60 degrees as claimed in claim 10 or 11 of the single layer full polyester composite. The temperature and time of the heat setting process are 235 ° C and 1 min, respectively, as claimed in claim 12 of the single-layered all-polyester composite. The single-layered all-polyester composite material according to claim 13, wherein the low-melting-point polyester resin is a polyester resin selected from the group consisting of adipic acid, sebacic acid, polyethylene glycol, and poly A product of copolymerization of a group consisting of propylene glycol, butylene glycol, isophthalic acid, and ethylene adipate. A method for manufacturing a continuous all-polyester composite material, comprising the steps of: forming a continuous polyester resin film by modifying a polyester resin to form the polyester resin film and a continuous polyester fiber; The difference in melting point of the cloth forms a working temperature window; the polyester resin film is laminated with the polyester fiber cloth by hot rolling to form a continuous all-polyester composite sheet; The all-polyester composite sheet is subjected to a cooling means to be wound up to complete the continuous all-polyester composite sheet. The method for producing a continuous all-polyester composite material according to claim 15, wherein the hot-rolling method is carried out by laminating the polyester resin film and the polyester fiber cloth together in a heating roller group. The heating roller set is subjected to high temperature and high pressure to first melt the polyester resin film into a melt fiber flow, and then extruded into the polyester fiber cloth to form an output of the continuous all-polyester composite sheet. The method for producing a continuous all-polyester composite material as described in claim 15 or 16, wherein the operating temperature window ranges from 10 to 60 degrees. The method for producing a continuous all-polyester composite material according to claim 17, wherein the polyester resin is selected from the group consisting of adipic acid, sebacic acid, polyethylene glycol, polypropylene glycol, butanediol, The group consisting of isophthalic acid and ethylene adipate is modified by copolymerization to lower the melting point to form the working temperature window. A full polyester product having a flexural surface, which is composed of a layer of a plurality of polyester fiber cloths laminated on each other and laminated with a low melting point polyester resin, wherein the manufacture of the all-polyester product having the flexible surface is formed The method comprises: passing each of the polyester fiber cloth through a heat setting process; modifying a polyester resin to lower the melting point and forming the film-like low-melting point polyester resin, and modifying the low-melting point polyester resin Forming a working temperature window different from the melting point of the polyester fiber cloth; interlacing more than one layer of the polyester fiber cloth with more than one layer of the low melting point polyester resin, and using a hot pressing process in the working temperature window The polyester fiber cloth is combined with the low melting point polyester resin to form the single layer full polyester composite material; the plurality of layers of the single layer full polyester composite material are stacked and combined with high temperature to make the low layer of each single layer full polyester composite material The melting point polyester resin forms a flow and then applies a high pressure combined with each single-layered full-polyester composite material to form a laminated full-polyester composite material sheet; the laminated all-polyester composite material sheet is formed into a deflection by a hot stamping method. A full polyester product on the surface. The polyester fabric having a flexible surface as described in claim 19, wherein the polyester fiber cloth is a fiber cloth woven from recycled polyester. The operating temperature window ranges from 10 to 60 degrees, as described in claim 19 or claim 20, wherein the operating temperature window is in the range of 10 to 60 degrees. The heat-setting process has a temperature and time of 235 ° C and 1 min, respectively, of the all-polyester product having a flexural surface as described in claim 21 of the patent application. The all-polyester product having a flexural surface according to claim 22, wherein the low-melting polyester resin is selected from the group consisting of adipic acid, sebacic acid, polyethylene glycol, and poly A product of copolymerization of a group consisting of propylene glycol, butylene glycol, isophthalic acid, and ethylene adipate. A single-layered all-polyester composite material comprising a polyester fiber cloth and a low-melting-point polyester resin closely coated with the polyester fiber cloth, wherein the low-melting point polyester resin has a lower melting point than the polyester fiber cloth . The single-layered all-polyester composite material according to claim 24, wherein the low-melting-point polyester resin lowers the melting point by a copolymerization method. The single-layered all-polyester composite material according to claim 25, wherein the low-melting-point polyester resin is a polyester resin selected from the group consisting of adipic acid, sebacic acid, polyethylene glycol, and poly A product of copolymerization of a group consisting of propylene glycol, butylene glycol, isophthalic acid, and ethylene adipate. The single-layered all-polyester composite material as described in claim 26, wherein the polyester fiber cloth and the low-melting-point polyester resin have a melting temperature difference of 10 to 60 degrees.