TW583215B - Transparent flexible polyester - Google Patents

Abstract

A transparent flexible polyester comprises as main components a copolyester comprising 99 to 40 mol% of a hard segment and 1 to 60 mol% of a soft segment. An unstretched sheet obtained by melt-molding said transparent flexible polyester has an elastic modulus of 18 to 1500 MPa, a crystallization index Xc of 5 to 33% measured by wide angle X-ray, and a haze (100 mum conversion) of 0 to 15% or less.

Description

583215 V. Description of the invention (1) [Technical Field] The present invention relates to a transparent soft polyester, which has excellent transparency, softness and handling properties, and can be used for sheets, films, mechanical plastics, pipes, packaging bags, Used for molded articles such as skins and stationery. [Background Art] In the past, polyvinyl chloride resin (hereinafter referred to as vinyl chloride) has been widely used in applications such as transparent and flexible molded articles such as sheets, films, tubes, and injection pharmaceutical bags. In order to make vinyl chloride flexible, a large amount of phthalate plasticizer is added. In addition, dioxin, which is carcinogenic, will be produced when burning vinyl chloride products. It must be avoided from the environmental and sanitary considerations. On the other hand, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polyethylene terephthalate-1 Polyester resin represented by 4-cyclohexyl dimethyl glycol ester (PCT) has no environmental and sanitary problems and has excellent physical and chemical properties. It is widely used in fibers, films, and plastics for machinery. , Bottles and other uses. However, it lacks flexibility and elasticity at room temperature and has the disadvantage of being hard, so it is not easy to expand its use. In order to improve this disadvantage, a variety of methods have been disclosed, such as adding a soft segment to a polyester and copolymerizing it to provide flexibility. For example, Japanese Unexamined Patent Publication No. 57-48577 and Japanese Unexamined Patent Publication No. 54- 1 59 1 3 disclose that a long-chain aliphatic dicarboxylic acid such as polybutylene glycol (PTMG) or a long-chain aliphatic dicarboxylic acid such as dimer acid (DiA) is used. Copolymerization of acid and PBT can provide softness. However, these copolyesters use polybutylene terephthalate 583215 in the hard segment. 5. Description of the invention (2) The crystalline phase of the ester (PBT), the molded body is easily crystallized, resulting in whitening. Low transparency and other issues. Representative polyester-based elastomers are, for example, Berry Plant (Toyobo) and Hyderia (Toray DuPont). Polyester elastomers can be classified into ether type using polyalkylene oxide diol (representative example: PTMG) and polyester using aliphatic polyester (representative example is polyhexamethylene) because of the type of hard segment that gives polyester flexibility. Lactone) and other types of esters. However, any one of the hard segments uses the crystalline phase of PBT. The biggest reason for using PBT in hard segments is its easy crystallinity. Among many polyesters, PBT has the highest crystallinity and can provide polyester elastomers with excellent moldability, handling, and productivity. However, in terms of imparting transparency to the polyester elastomer, the easy crystallinity of PBT constitutes a major obstacle. A method of disturbing the crystal structure by adding an acid component other than terephthalic acid (TPA) to PBT to improve transparency has been proposed from the past. However, this method has problems such as a decrease in Tg and a softening point, and an increase in adhesion, which may cause problems such as blocking when the resin dries, and poor moldability such as poor moldability and processability. On the other hand, many attempts have been made to develop polyester elastomers using polyethylene terephthalate as a hard segment. For example, Japanese Patent Application Laid-Open No. 48-5 523 and Japanese Patent Application Laid-Open No. 42-8709 disclose the technique of adding PTMG and DiA to PBT for copolymerization to make it flexible. However, these polyester copolymers form a transparent and soft molded body immediately after molding, and crystallizing at a temperature higher than the glass transition point (Tg) causes problems such as low transparency due to whitening. In addition, if the copolymerization amount of PTMG and DiA is increased, Tg and softening point will be increased.

583215 V. Description of the invention (3) The adhesiveness will increase when it decreases. For this reason, serious problems such as deterioration in the separation from the mold and the roller during molding, the inadequate adhesion between the sheets when the sheet is rolled, and the occurrence of occlusion when the resin is dried, occur in handling. Japanese Unexamined Patent Publication No. 2-2425 19, Japanese Unexamined Patent Publication No. 6- 1 283 63, and USP 4,4 5 1,641 disclose that two polyesters composed of TPA and ethylene glycol (EG) or TMG are used. A technique in which polymer diol (DDO) is copolymerized to make it flexible, but all use the crystalline phase of PBT in the hard segment, which causes problems such as whitening due to crystallization and low transparency. In addition, Japanese Patent Publication No. Sho 595 1 42 discloses a resin composition in which a sodium salt of a carboxylic acid is added to a copolyester using a polyalkylene oxide in a hard segment. Copolyesters have a composition ratio of dimer acid (DiA), ethylene glycol (EG), and butanediol (BD). However, the copolyesters prepared according to these methods lose transparency due to whitening caused by crystallization in an unstretched state, and because they have adhesiveness, they have poor release properties from molds or rollers, and adhesion between the molded bodies occurs. Etc. make handling poor. That is, at present, a transparent soft polyester having sufficient transparency, softness, and handling properties has not been developed. In view of the above circumstances, the present invention aims to provide a transparent and flexible polyester which is suitable for molding applications such as sheet, film, mechanical plastics, pipes, packaging bags, skins, and stationery, and has excellent transparency, softness, and handling properties. [Disclosure of the invention] The first invention of the present invention is a transparent soft polyester whose main component is a copolyester formed by a hard segment and a soft segment.

583215 V. Description of the invention (4) The elastic modulus of the unstretched sheet obtained by melt molding of the ester is less than 1 500 MPa, the crystallization index Xc measured by wide-angle X-ray is greater than 5%, and the haze of this sheet (converted to 100 μηι) is less than 15%. The second invention, such as the transparent soft polyester of the first invention, is characterized in that at least 70 mole% or more of the dicarboxylic acid component constituting the hard segment is at least one selected from terephthalic acid (TAPA), 2, 6-naphthalenedicarboxylic acid (NDA), 4,4 · -biphenyldicarboxylic acid (BPA). The third invention, such as the transparent soft polyester of the first or second invention, is characterized in that the diol component constituting the hard segment contains 1,4-butanediol (TMG) and ethylene glycol (EG), and The composition ratio of the total diol component constituting the hard segment is TMG of 20 to 95 mole% and EG of 5 to 80 mole%. The fourth invention is the transparent soft polyester according to any one of the first, second, and third inventions, characterized in that the soft component constituting the soft segment is at least one or more kinds selected from the group consisting of a number average molecular weight of 100 to 1.0. A long-chain aliphatic dicarboxylic acid of 0%, a long-chain aliphatic diol having a number-average molecular weight of 100 to 1,000, and a polyalkylene oxide diol having a number-average molecular weight of 500-4,000. The fifth invention is the transparent soft polyester according to any one of the first, second, and third inventions, which is characterized in that the soft component constituting the soft segment is a dimer diol (DDO), and is The composition ratio of the diol component and DDO is 1 to 60 mol%. The transparent and flexible polyester of the sixth invention, such as the first invention, is characterized by containing 0.5 to 5.0% by weight of a metal element. This metal element contains Metal salt compounds of Group Ia or Group III-a metal elements of the periodic table. The transparent soft polyester of the present invention is a copolymer formed of a hard segment and a soft segment

583215 V. Description of the invention (5) Transparent and soft polyester whose main component is ester. The purpose of introducing hard segments in the polyester molecular chain is to make the polyester occlusive and transparent. On the other hand, it is introduced into the polyester molecular chain. The purpose of the soft segment is to make the polyester soft. The transparent soft polyester of the present invention melt-molds the transparent soft polyester, and has an elastic modulus of less than 1; 500 MPa · as an unstretched sheet, so its softness is superior. The transparent soft polyester of the present invention is a wide-angle X-ray The measured crystallization index XC is greater than 5%, so it has superior handling properties. In addition, the haze of the unstretched sheet obtained by melt molding of this transparent soft polyester is less than 1: 5% in terms of sheet thickness of 100 μm, so its transparency is excellent. The transparent soft polyester of the present invention will be described in detail below. Instance type. (Hard chain segment) To develop transparent and soft polyester that has three properties of transparency, softness, and processing at the same time, the most difficult technical problem is to have both transparency and processing. Therefore, it is important to design hard links that can restrain soft links. From the viewpoint of crystallization, transparency and processing are two opposite properties. Because the transparency will worsen as the crystallization progresses, conversely, the handling properties can be improved. That is, y has both the transparency and the processing properties. The two opposite characteristics are the most important technical subjects in the present invention. — * In general, when PET with a slow crystallization rate is molded, it is rapidly cooled from the molten state to form a supercooled state (amorphous state), and a transparent molded body can be obtained. However, when the prepared molded body is placed at a temperature higher than Tg, it will crystallize to form a whitening phenomenon. This phenomenon is a result of the simultaneous crystal growth as the crystallization progresses. Therefore, -7 1 is required to have good transparency.

583215 V. Description of the invention (6) The smaller the size of the crystal, the better, that is, microcrystals must be formed. On the other hand, the handleability, that is, the occlusive property when the resin is dry or the dissociation property from the mold or roller during the molding process, or the adhesion between the molded bodies, etc., is not affected by the degree of crystallization, which is related to the crystal size. Effect of crystallinity. The degree of crystallinity is defined as the number of crystals multiplied by the crystal size. As can be seen from the above, when constituting a hard segment in a crystalline phase, two elements must be provided, that is, the size of crystals is formed into microcrystals from the viewpoint of transparency, and a large number of them are treated from the viewpoint of handling properties affected by the degree of crystallinity. Microcrystals and other two elements. Therefore, the choice of the polymer structure constituting the hard segment is very important. Generally, polyesters have large differences in crystallinity due to the structure of the polymer. For example, the typical crystallinity of PET and PBT is very different, and the crystallization rate of PBT is very fast. From the viewpoint of having both transparency and handling properties, the required properties in the crystalline phase are microcrystals formed in a large amount. The composition of the polyester which satisfies these elements can be obtained by using, for example, a hard segment which satisfies the following two conditions, thereby obtaining a polyester having both transparency and handling properties. (1) The polyester constituting the hard segment, in which the diol component includes 1,4-butanediol (TMG) and ethylene glycol (EG), and the total glycol component of the polyester constituting the hard segment The composition ratio is 20 to 95 moles. / 〇, EG is 5 to 80 mole%. (2) The polyester constituting the hard segment, in which the dicarboxylic acid component is at least one selected from terephthalic acid (TPA), 2,6-naphthalenedicarboxylic acid (NDA), 4,4'-biphenyl Dicarboxylic acid (BPA), and the content is greater than 70 mole%.

583215 V. Description of the invention (7) When the above 2 conditions cannot be met, microcrystals cannot be formed, whitening phenomenon is formed, transparency is lost, softening point is reduced, adhesion is increased, and handling properties of the resin when drying and molding are poor, which is not practical. Price. The composition of the polyester constituting the hard segment, in which the diol component is preferably 23 to 94 mole% / 77 to 6 mole% of TMG / EG, and 25 to 9 3 mole% of TMG / EG / 7 5 to 7 mole% is particularly desirable. On the other hand, the di-residual acid component is at least one selected from the group consisting of TPA, NDA, and BPA, and the content is more than 75 mole%, and the content is more than 80 mole%. In addition to the dicarboxylic acids described above, the polyester constituting the hard segment may use dicarboxylic acids such as isophthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, and diol components. Diols such as 1,3-propanediol, 1,4-cyclohexanedimethanol, and 1,6-hexanediol are used as copolymerization components. Further, the use of a metal compound as a crystallization accelerator is effective for microcrystallization, and is more preferable from the viewpoint of transparency. In particular, a metal salt compound containing a metal element belonging to Group I-a or Group Π-a of the periodic table is preferable for the transparent soft polyester of the present invention. Among them, lithium, sodium, potassium, and calcium salts of aliphatic carboxylic acids or phosphorus compounds are preferable. The content of the metal salt compound varies depending on the composition of the polyester, and it is effective for the polyester to contain a metal element in an amount of 0.5 to 5.0% by weight. If the content of the metal salt compound is less than 0.5% by weight, the effect of promoting crystallization is small. Conversely, when it exceeds 5.0% by weight, not only the dispersibility in the polyester is poor, but the moldability and physical properties are significantly deteriorated. Relative to polyester, the lower limit of the content of the metal salt compound 値 is preferably 0.8% by weight, and particularly preferably 0.1% by weight. The upper limit 値 is more preferably 4.5% by weight, and particularly preferably 4.0% by weight.

583215 V. Description of the invention (8) (Soft segment) The soft segment is indispensable for supplying the softness of polyester, and it is important to have the flexibility of commission. Suitable soft ingredients such as polyalkylene oxide diol, aliphatic polyester, long-chain aliphatic dicarboxylic acid, long-chain aliphatic diol, and the like. When a long-chain aliphatic dicarboxylic acid and a long-chain aliphatic diol are used as the soft component, if the number average molecular weight is less than 1,000, it is difficult to have sufficient flexibility. On the other hand, if the number-average molecular weight exceeds 1,000, the compatibility with the hard segment becomes poor, and the transparency tends to decrease. Moreover, when using a polyalkylene oxide glycol, even if the number average molecular weight is less than 500 or more than 4,000, the transparent soft polyester required for the objective cannot be obtained. In the present invention, the soft component of the transparent soft polyester is most effective from the viewpoint of transparency, and the dimer diol (DDO) of the long-chain aliphatic diol is most effective. The composition ratio of DDO varies depending on the desired flexibility, and it is 1 to 60 moles for the total glycol component of polyester. / 〇 is more preferable, 2 to 58 mole% is more preferable, and 3 to 55 mole% is particularly preferable. If the composition ratio of DDO is less than 1 mole%, the flexibility is insufficient and hard. On the other hand, if it exceeds 60 mol%, Tg is too low, and moldability, processability, and handleability tend to deteriorate. (Polymerization of Copolyester) A conventionally known method can be applied to the polymerization method of the copolyester. For example, esterification or transesterification of aromatic dicarboxylic acids and their lower alkyl esters with glycols such as ethylene glycol, propylene glycol, butanediol, 1,4-cyclohexyldimethyl glycol, and dimer glycol. The reaction method is the most common. In the production of the copolyester, for example, a known metal compound of titanium, zinc, manganese, cobalt, lead, calcium, and magnesium can be used as the transesterification catalyst. Examples of polycondensation catalysts

-10- 583215 V. Description of the invention (9) For example, metal compounds such as titanium, antimony, germanium, and tin can be used. In addition to these catalysts, thermal oxidation stabilizers or phosphorus compounds can be added. (Melting and Mixing of Metal Salt Compound) To mix the metal salt compound with the polyester, the metal salt compound can be added to the melting process of the polyester through a uniaxial extruder, a biaxial extruder, or during the molding process. For example, the following description uses a biaxial extruder to mix a metal salt compound with polyester. A two-axis extruder (manufactured by Toshiba Machinery Co., Ltd., TEM-37BS) was used to mix the metal salt compounds. When mixing, the resin temperature is 25 Ot, the number of screw rotations is 100 rpm, the vacuum degree of the vent is 1 to 5 hPa, and the feed amount is I5 kg / hr. Water-cooled to cut into a pointed shape. In addition, when the metal salt compound is mixed, a pigment that does not adversely affect the ultraviolet absorber and transparency can be blended at the same time. (Characteristic 値) In the present invention, characteristics 弹性 such as elastic modulus, crystallization index Xc, and haze are used to express the characteristics of the transparent soft polyester. The elasticity is an index of the softness of the transparent soft polyester. The flexibility can be controlled, for example, by the structure of the hard segment, the type and amount of the soft segment used. The larger the elastic rate, the harder it is, and the smaller it is, the softer it is. Generally speaking, when the transparent soft polyester is made into a sheet with a thickness of 100 μm, its elasticity is less than 1 200 MPa, that is, it has flexibility, preferably less than 1 150 MPa, and particularly preferably less than 110 MPa. The crystallization index Xc is an index indicating the degree of microcrystallization.

-11- 583215 V. Description of the invention (1〇) is an important index. For example, Xc can be controlled from the structure of the hard segment. From the viewpoint of handling, the larger Xc is, the better, it must be more than 5%, more preferably more than 6%, and more preferably more than 7%. Haze is an index indicating the transparency of a molded body of a transparent soft polyester. The smaller the haze, the better the transparency. When making a sheet with a thickness of 100 μm, it must be less than 10%, preferably less than 9%, and particularly less than 8%. If the haze exceeds 10%, the whitening phenomenon is obviously not transparent. In addition, by containing the metal salt compound of the present invention, the haze can be improved and the transparency can be improved. The effect of improving the haze due to the inclusion of a metal salt compound is better than 0.2% less than the haze of a metal salt-free compound. If the haze improvement effect is less than 0.2%, the difference in transparency is hardly seen visually. The more ideal improvement effect is more than 0.3%, and more than 0.4% is particularly desirable. Generally, the Tg of the polyester having softness is lower than normal temperature. After the Tg is increased, the softness of the polyester is insufficient under normal use conditions. The transparent soft polyester of the present invention also has a low Tg. Therefore, although the molded body obtained by melt molding has transparency immediately after molding, if it is left in an environment larger than Tg, crystals will gradually be formed, and the transparency will be deteriorated due to the whitening phenomenon. This phenomenon is caused by rapid cooling from a molten state to a supercooled state (amorphous state) and crystallization at a temperature greater than Tg. The molded body obtained by rapidly cooling the transparent soft polyester of the present invention from a molten state has been microcrystallized during the cooling process, so that its crystals do not grow even when left at a temperature higher than Tg, and no whitening phenomenon occurs. This point is the greatest feature of the transparent soft polyester of the present invention.

-12- 583215 V. Description of the invention (11) The transparent soft polyester thus obtained can be used as a molded body such as a sheet, a film, a mechanical plastic, a tube, a packaging bag, a skin, a stationery or the like. At this time, the polyester may be laminated and blended with other resins such as polyethylene and polypropylene, or polyesters, carbonates, and vinyl chloride. Examples Next, the transparent soft polyester of the present invention will be described in more detail with examples and comparative examples, but the present invention is not limited to the examples shown below. The properties of the transparent soft polyester obtained in this example were evaluated by the following methods. (1) Preparation of test specimens After the resin was dried under reduced pressure at 7 ° C for a whole day, an unstretched sheet having a thickness of about 100 μL was prepared according to the following operation. On a flat metal plate It is placed in the same order as a thin film (manufactured by Toray DuPont), a metal spacer (thickness: 0.5mm) cut in a desired shape, and resin particles that can only satisfy this shape are placed in this shape. Then put the cloth, film, and metal plate in order. Move these to the compression surface of the hydraulic press (made by Kudo Metal Industry Co., Ltd., West type F), and the melting point is 20 ~ 30 ° C higher than the melting point. After melting for 4 minutes at a high temperature, it is compressed at 9.8 MPa (100 kgf / cm2) for 1 minute at the same temperature. The sheet is moved to ice water for rapid cooling within 5 seconds after compression. After rapid cooling, the water on the surface of the sheet is wiped off immediately And stored in a dry box at 25 ° C for 24 hours. (2) Elasticity After the test specimen stored in the dry box is moved to room temperature for more than 30 minutes, it is measured based on ASTM-D63 8 Elasticity of the sheet (3) Crystallization index Xc

-13- 583215 5. Description of the invention (12) Take out the test specimen for measurement from the storage container, leave it at room temperature for more than 30 minutes, and cut it into pieces with a size of 20mm x 18mm, and use it as a test specimen for wide-angle X-ray refraction. The measurement of X-ray refraction is based on the method described in "Introduction to X-ray Analysis Revision 3rd Edition, page 84, Issue 1 985.6.30, Rigaku Electric Co., Ltd.", and is determined by the reflection method under the measurement conditions shown below 2 0-X-ray intensity slice. (Measurement conditions) X-ray generator Target voltage, current Scanning speed Slit Ricc company copper 40kV, 37.5mA 0.5. / mi η Kayk-Plex divergence slit Γ Scattering slit Γ Scattering slit Γ Receiving slit 0.3mm Monochromator: Counter monochromator [Graphite (0002)] (Definition of Crystallization Index Xc) Find A moving average approximation line (range ·· 30) of a cross-sectional view of the intensity of the 20-X line obtained in the X-ray measurement. Because the X-ray intensity of the vertical axis changes depending on the thickness and thickness of the test product, even if it is expanded or contracted, the ratio of its peak height does not change, and each moving average approximate line becomes the X-ray intensity at 20 = 13 °. It is 250 cps once. Transform each frame. Find the moving average approximation line and connect it with 以 at 20 = 9 ° and 3 5 ° as the bottom line to form -14-583215. V. The area of the scope of the invention description (13) (refer to the figure below). Scattering cross-section diagrams when the diol component of the hard segment is EG 100 mole% (for example, Example 3) are derived from the amorphous structure. When the composition ratio of the soft segment is maintained constant, the diol composition of the hard segment is changed. The difference in the scattering cross-section diagrams (for example, Example 1) at this time comes from the crystal structure, and the definition of the crystallization index Xc is as follows. Crystallization index Xc (%) = ((B-A) / A) xl00 In the above formula, 'A represents the area from the scattering section of the amorphous structure' and B represents the area of the scattering section from the crystalline structure. 5 0 5 0 2 0 7 5 11 (sdo)

20 (degrees) (4) Haze After taking out the test specimen for measurement from the storage container and leaving it at room temperature, it was measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., Model NDH2000). The haze 薄片 having a sheet thickness of 100 μm is converted by the following formula. Haze (%) = Ηζ (%) χ100 (μηι) / Α (μηι) Ηζ (%) is the actual measurement of the test specimen, A is the measured thickness of the test specimen (μπ〇. -15-583215

V. Explanation of the invention (14) (5) Reduced viscosity Reduced viscosity (nsp / C) is the test product 0.1 g dissolved in 25ml of phenol / tetrachloroethane = 60/40 (weight ratio) mixed solution ' Measured using Ostwald viscosity at 30 ° C. (6) Composition analysis The composition analysis of polyester was performed by dissolving the test product in a mixed solvent of trichloromethane / trichloroacetic acid = 9 0/10 (volume ratio), and using an NMR spectrometer (manufactured by Barion, Unity-500). (7) Melting point (7 -1) The melting point of the metal salt compound is charged with a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-50) in an aluminum container of 5 to 10 mg. The temperature is increased at a rate of 2 ° C / min in a nitrogen atmosphere. An endothermic peak appears when the temperature is increased, and the peak temperature in the highest temperature range is its melting point (Tm). (7-2) The melting point of polyester uses a differential scanning type A calorimeter (manufactured by Shimadzu Corporation, DSC-50), 10 mg of a test article was filled in an aluminum container, and the temperature was raised to 290 ° C at a rate of 20 ° C / min in a nitrogen-filled environment. Maintained at After 3 minutes at the same temperature, put the aluminum container into liquid nitrogen for rapid cooling. The rapidly cooled aluminum container was set on the differential scanning calorimeter again, and the temperature of the endothermic wave peaks appeared when the temperature was raised at 20 ° C / min. The peak temperature is the melting point. (Example 1) 83,800 parts by weight of dimethyl terephthalate (DMT), 26,200 parts by weight of EG, 38,100 parts by weight, and DDO -16-583215 were placed in a transesterification furnace. 、 Explanation of invention (15) (produced by Niuke Slow Co., Ltd., PRIPOL203 3) 1 0,000 parts by weight of catalyst 100 parts by weight of butyl titanate (TBT), 200 parts by weight of stabilizer Irganox 100 (IRG, Ciba Gage Corporation), and 200 parts by Yadenkasamp PEP-3 6 (PEP, Asahi Denka Corporation) 200 By weight, the internal temperature is increased from 120 ° C to 226 ° C in 90 minutes, and the same temperature is maintained for 20 minutes to carry out the transesterification reaction. Next, the transesterification reaction product is transferred to a polycondensation reaction furnace, and within 75 minutes The temperature in the furnace was increased from 220 ° C to 250 ° C. At the same time, the pressure in the furnace was gradually reduced to a final pressure of 0.8 hPa. Under this condition, the polycondensation reaction was continued until the melt viscosity of the content was 3000 dPa · s. The contents were released in water under slight pressure of nitrogen and cut into a tip shape. The composition of the obtained polyester is shown in Table 1, and the characteristics of the polyester and the characteristics of the sheet are shown in Table 2. (Example 2 ~ 4, Comparative Examples 1 ~ 3) A polyester was prepared in the same manner as in Example 1 except that the composition of EG and TMG was changed to that shown in Table 1. The properties of the obtained polyester and the properties of the sheet were as shown in the table. Shown in 2. (Example 5) Based on Example 1, DMT 6 8, 3 00 parts by weight, EG 22,700 parts by weight, TM G3 0,0 00 parts by weight, 3,000 parts by weight of DDO, 1,000 parts by weight of TBT, 200 parts by weight of IRG, and 200 parts by weight of PET. Transesterification reaction and polycondensation reaction are performed to obtain a transparent soft polyester. The composition of the obtained polyester is as follows As shown in Table 1, the characteristics of the polyester and the sheet are shown in Table 2. (Conventional Examples 6 to 9, Comparative Examples 4 to 5) In addition to changing the composition of EG and TMG as shown in Table 丨, and A polyester was obtained in the same manner as in Example 5. Characteristics and flakes of the obtained polyester

-17- 583215 5. The characteristics of the invention description (16) are shown in Table 2. (Example 10) Based on Example 1, DMT 44,3 00 parts by weight, EG 4.900 parts by weight, TMG 23,900 parts by weight, DDO 60.000 parts by weight, TBT 100 parts by weight, IRG 200 parts by weight, PEP 200 parts by weight, and esters were used. The exchange reaction and the polycondensation reaction make transparent soft polyester. The composition of the obtained polyester is shown in Table 1. The properties of the polyester and the properties of the sheet are shown in Table 2. ((Examples 11 to 14, Comparative Examples 6 to 7) A polyester was prepared in the same manner as in Example 10 except that the composition of EG and TMG was changed to that shown in Table 1. The characteristics and the sheet of the polyester were obtained. The characteristics are shown in Table 2. (Example 15) Based on Example 1, 54.100 parts by weight of dimethyl 2-naphthalene dicarboxylate (DMN), 22,300 parts by weight of EG, 29,500 parts by weight of TMG, and DDO were used. 18,800 parts by weight, 100 parts by weight of TBT, 200 parts by weight of IRG, and 200 parts by weight of PEP, transesterification reaction and polycondensation reaction were performed to obtain a transparent soft polyester. The composition of the obtained polyester is shown in Table 1. Polyester Table 2 shows the properties and properties of the sheet. (Example 16) Based on Example 1, 3,4'-dimethylbiphenyl carbonate (DMB) 38,000 parts by weight, EG 4,500 parts by weight, TMG 23,50 parts by weight, 000 3 9,7 00. parts by weight, 8 parts by weight but 100 parts by weight, 111 parts by weight (200 parts by weight, 200 parts by weight of PEP), transesterification reaction and polycondensation reaction are performed to obtain a transparent soft polyester The composition of the obtained polyester is shown in Table 1. The characteristics of the polyester and the properties of the sheet are shown in Table 2. -18-583215 V. Description (17) Table 1 Hard segment soft segment dicarboxylic acid component (mol%) Glycol component (mol%) Glycol component (mol%) DMT DMN DMB TMG EG DDO Example 1 100 0 0 80 20 4.1 Example 2 100 0 0 55 45 4.5 Example 3 100 0 0 70 30 4.5 Example 4 100 0 0 74 26 4.9 Comparative Example 1 100 0 0 100 0 4.5 Comparative Example 2 100 0 0 96 4 4.4 Comparative Example 3 100 0 0 0 100 4.0 Example 5 100 0 0 60 40 15.5 Example 6 100 0 0 55 45 15.0 Example 7 100 0 0 65 35 15.0 Example 8 100 0 0 70 30 16.0 Example 9 100 0 0 85 15 16.0 Comparative Example 4 100 0 0 10 90 15.5 Comparison Example 5 100 0 0 100 0 16.0 Example 10 1 00 0 0 92 8 49.5 Example Π 100 0 0 60 40 46.0 Example 12 100 0 0 70 30 46.0 Example 13 100 0 0 78 22 48.5 Comparative Example 6 100 0 0 15 85 50.5 Comparative Example 7 100 0 0 0 100 50.0 Example 14 0 100 0 87 13 15 Example 15 0 0 100 90 10 50 -19- 583215 V. Description of the invention (18) Table 2 Characteristics of polyester Sheet characteristics Melting point reduction viscosity haze elasticity Rate crystallization (° C) (dl / g) (%) (MPa) Index Xc (%) Example 1 198 0.83 1.1 1330 26.7 Example 2 179 0.84 1.4 1250 10.3 Example 3 186 0. 85 0.9 1150 23.4 Example 4 188 0.82 0.8 1200 25.1 Comparative Example 1 218 0.89 23.6 1550 35.6 Comparative Example 2 214 0.82 21.2 1510 32.8 Comparative Example 3 248 075 1.0 1740 0 Example 5 158 0.87 1.9 143 28.7 Example 6 157 0.83 2.1 125 26.6 Example 7 161 0.84 1.6 151 29.4 Example 8 168 0.85 1.1 155 29.8 Example 9 179 0.88 7.8 295 39.2 Comparative Example 4 206 0.81 1.7 320 0.3 Comparative Example 5 196 0.90 22.3 580 43.1 Example 10 120 0.85 0.8 29 18.6 Example 11 98 0.84 1.3 22 6.1 Example 12 102 0.81 1.4 23 8.8 Example 13 106 0.83 1.5 25 13.4 Comparative Example 6 1 18 0.80 2.2 38 0 Comparative Example 7 158 0.79 2.9 29 0 Example 14 196 0.76 3.6 236 23.9 Example 15 161 0.73 1.8 40 1 1.6 -20- 583215 V. Description of the invention (19) (Example 16) The transparent soft polyester obtained in Example 1 was dried under reduced pressure at 70 ° C for one day and night, and then a biaxial extruder (manufactured by Ikegai Iron Works, PCM-30) was used. ) Melted at a resin temperature of 220 ° C and a screw rotation speed of 150 rpm, and extruded on a cold-hard roll with a surface temperature of 30 ° C with a T-die extrusion die to obtain an unstretched sheet having a thickness of 45 μm. The characteristics of this sheet are shown in Table 3. (Example 17) The transparent soft polyester obtained in Example 8 was dried under reduced pressure for one day and night at 70 ° C, and then a biaxial extruder (manufactured by Ikegai Iron Works, PCM-30) was used at a resin temperature of 200 ° C. 1. Melt under the conditions of a screw rotation number of 150 rpm, and extrude on a cold hard roll with a surface temperature of 3 CTC using a T-die extrusion die to obtain an unstretched sheet with a thickness of 45 μm. The characteristics of this sheet are shown in Table 3. (Example U) The transparent soft polyester obtained in Example Π was dried under reduced pressure at 70 ° C for one day and night, and then a biaxial extruder (Ikegai Iron Works, PCM-30) was used at a resin temperature of 200 ° C. 1. Melt under the conditions of screw rotation speed of 150 rpm, and extrude on a cold-hard roll with a surface temperature of 30 ° C by a T-die extrusion die to obtain an unstretched sheet with a thickness of 450 μm. The characteristics of this sheet are shown in Table 3. (Comparative Example 8) The copolyester obtained in Comparative Example 3 was dried under reduced pressure at 70 ° C for one day and night, and then the resin temperature was 270 ° using a biaxial extruder ("PCM-30" manufactured by Ikegai Iron Works). C. Melt under the conditions of screw rotation speed of 150 rpm, and extrude on a cold hard roll with a surface temperature of 30 ° C with a T-die extrusion die to obtain an unstretched sheet with a thickness of 45 μm. The characteristics of this sheet are shown in Table 3.

-21-583215

V. Description of the invention (20) (Comparative Example 9) The copolyester prepared in Comparative Example 5 was dried under reduced pressure at 70 ° C for one day and night, and then a biaxial extruder (Ikebe Iron Works' PCM) was used. -30) Melt at a resin temperature of 220 ° C and a screw rotation speed of 150 rpm. 'Extruded with a T-die extrusion die on a cold hard roll with a surface temperature of 30 ° C to produce an unstretched sheet with a thickness of 45 μm . The characteristics of this sheet are shown in Table 3. (Comparative Example 10) The copolyester obtained in Comparative Example 6 was dried under reduced pressure at 70 ° C for one day and night, and then was extruded using a two-axis extruder (Ikegai Iron Works, PCM-30) at a resin temperature of 220 ° C. Melt under the conditions of screw rotation speed of 150 rpm, and extrude on a cold-hard roll with a surface temperature of 30 ° C using a T-die extrusion die to obtain an unstretched sheet with a thickness of 4 5 μm. The characteristics of this sheet are shown in Table 3. Table 3 Characteristics of polyester and sheet used _______ Haze (%) Crystallization Index Xc (%) Elasticity (%) Falling Strength (MPa) Breaking Strength (MPa) Breaking Elongation (%) Example 16 Example 1 3.5 27.8 1380 42.6 38.6 268 Example 17 Example 8 2.1 31.1 168 8.3 11.6 ^ 400 Example 18 Example 11 2.1 19.5 18 6.0 8.5 ^ 400 Comparative Example 8 Comparative Example 3 1.1 0 1740 52.6 52.6 3.7 Comparative Example 9 Comparative Example 5 95.3 42.3 563 44.1 65.8 ^ 400 Comparative Example 10 Comparative Example 6 1.0 0.6 38 6.3 9.5 ^ 400 * However, the breaking elongation is the upper limit measurable by 400 series (Examples 19 to 21, Comparative Example Π)

-22- 583215 V. Description of the invention (21) The flakes prepared in Examples 16 to 18 and Comparative Example 8 were placed in an oven under a nitrogen atmosphere at 70 ° C. (: 24 hours heat treatment. The measurement results are shown in Table 4. Table 4 Characteristics of the sheet used Sheet Haze (%) Crystallization Index Xc (%) Elasticity (MPa) Example 19 Example 16 3.8 29.6 1520 Example 2 0 Example 17 2.2 33.0 216 Example 21 Example 18 2.1 20.6 21 Comparative Example 1 1 Comparative Example 8 38.5 39.8 2000 Examples 22 to 3 0 and Comparative Examples 1 2 to 1 Examples of 6-series copolyesters containing metal salt compounds. (Examples) 22 to 25, Comparative Examples 12, 13) In Example 22, the polyester obtained in Example 4 was used, and the metal salt compound shown in Table 5 was used as a metal element, and the content was 2.5% by weight of the polyester for melt mixing. In Examples 23 and 24, the polyester prepared in Example 5 was used, and the metal salt compound shown in Table 5 was used as the metal element, and the content was 1.5% by weight of the polyester in Example 23 and the polyester in Example 24. 2.5% by weight was melt-mixed. In Example 25, the polyester obtained in Example 10 was used, and the metal salt compound shown in Table 5 was used as a metal element, and the content was 2.5% by weight of the polyester for melt-mixing. Polyester prepared in Example 12 using Example 8 The metal salt compound shown in Table 5-23-583215 V. Description of the Invention (22) was used as the metal element, and its content was 5.2% by weight of the polyester for melt mixing. Comparative Examples 1 to 3 were prepared using the polymer prepared in Comparative Example 2. For the ester, the metal salt compound shown in Table 5 is used as the metal element, and the content is 2.5% by weight of the polyester. The results are shown in Tables 5 and 6. According to Tables 5 and 6, the polyester-containing 0.5 to 5.0% by weight of the metal salt compound is a metal element flake, which has a smaller haze and improves its transparency than a flake containing no metal salt compound. In addition, as the soft component increases, the haze reduction rate has However, the content of the metal salt compound in Comparative Example 12 exceeded 5 wt./°, and it was impossible to obtain a sol-solubilized flake of the molten resin. In Comparative Example 13, two of the copolyester were used. The TMG composition ratio of the alcohol component is greater than 96 mol%, and the resulting flakes are crystallized and whitened, and the transparency cannot be improved even if the metal salt compound is contained. (Example 26) Put DMT in a transesterification reactor 69,800 parts by weight, EG 35,200 Parts by weight, TMG 1 3,700 parts by weight, PTMG (manufactured by Hodogaya Chemical Industry Co., Ltd., TPG 1 000) 30,000 parts by weight, 53 parts by weight of antimony trioxide catalyst, zinc acetate and dihydrate 53 parts by weight, 200 parts by weight of IrgznoZ1 3 30 (manufactured by Ciba Geigy) with a thermal oxidation stabilizer, the internal temperature was increased from 120 ° C to 220 ° C in 90 minutes, and maintained at the same temperature for 20 minutes to A transesterification reaction is performed. Next, the transesterification reaction product was transferred to a polycondensation reaction furnace, and the temperature in the furnace was increased from 220 ° C to 25 ° C in 75 minutes. While gradually lowering the furnace

-24- 583215 V. Description of the invention (23) Pressure makes the final pressure to 0.9hPa. The polycondensation reaction was continued under this condition until the melt viscosity of the content was 30 OPa · s, and then the content was extruded under nitrogen pressure and cut into a tip shape. This resin contained 2.5% by weight of a metal salt compound sodium caprylate (C8-Na) as a metal element, and was dried under reduced pressure at 100 ° C for one day and night. The dried resin was fed into a belt-type two-axis extruder (manufactured by Toshiba Machine Co., Ltd., TEM-37BS), and the resin was fed at a resin temperature of 250 ° C, a screw rotation number of 100 rpm, a vent vacuum of lhPa, and a resin feed. The metal salt compound was uniformly melt-mixed under the condition of an amount of 15 kg / hr. Next, the resin containing the metal salt compound was dried under reduced pressure at 10 (TC for one day and night), and then a biaxial extruder (Ikegai Iron Works Co., Ltd., PCM-3 0) was used to rotate the screw at a resin temperature of 200 ° C. It was melted under the condition of several 150 rpm, and the molten resin was extruded on a cold-hard roll with a surface temperature of 30 ° C by a T-die extrusion die to obtain an unstretched sheet having a thickness of 500 μm. (Examples 27 to 28, Comparative Examples 14 to 15) The same as Example 26, except that the composition ratio of TMG / EG, the molecular weight and composition ratio of PTMG, and the type and content of the metal salt compound in Example 26 were changed. An unstretched sheet was prepared by the method. The results are shown in Tables 5 and 6. When the content of the metal salt compound as the metal element is 0.5 to 5.0% by weight of the polyester, the haze becomes small and the transparency is increased. In particular, in Example 27, 'a suitable amount of a metal salt compound was melt-mixed, and no occlusion occurred between the sheets immediately after the film formation, and a transparent sheet was obtained. However, among the metal salt compounds of Comparative Example 14 which are metal elements in Comparative Example 14 Content is

-25- 583215 V. Description of the invention (24) 0.4% by weight of polyester, even if it contains metal salt compounds, its haze is only reduced by 0.1%, and the effect of improving transparency is hardly achieved. On the other hand, the content of the metal salt compound as a metal element in Comparative Example 15 was 5.3% by weight of the polyester, and the molten resin was gelatinized, and a sheet could not be obtained. In addition, the molecular weight is greatly reduced. (Example 29) 49,300 parts by weight of DMT, 29,200 parts by weight of EG, 10,600 parts by weight of TMG, 150 parts by weight of Irgznozl330 (manufactured by Ciba Geigy), a thermal oxidation stabilizer, were placed in a transesterification reactor, and trioxide of the catalyst 38 parts by weight of antimony and 63 parts by weight of zinc acetate dihydrate were subjected to transesterification. Next, 22.5 parts by weight of a dimer (Nokima Co., Ltd., PRIPOL 1 009) was added to the transesterification reaction, and the mixture was stirred at 220 ° C for 30 minutes to perform a polycondensation reaction. To this resin was added 2.5% by weight of a metal salt compound Cs-Na ', which was uniformly melt-mixed at 240 t to obtain a sheet by manual pressing. The results are shown in Tables 5 and 6. (Example 3 0, Comparative Example 1 6 to 17) Except changing the TMG / EG composition ratio of the copolyester, the composition ratio of the dimer acid (DiA), the type and content of the metal salt compound in Example 29, and An unstretched sheet was prepared in the same manner as in Example 29. The results are shown in Tables 5 and 6. In the examples, the transparency and handling properties of the sheet have been improved, but Comparative Example 16 has a composition ratio of EG of 97 mol% relative to the total diol component constituting the hard segment of the polyester, and Comparative Example 17 of which No metal salt compound was contained, and occlusion occurred in both cases, and flakes could not be obtained.

-26- 583215 V. Description of the invention (25) Table 5 Characteristics of hard segment and soft segment of transparent soft polyester metal salt compound 値 Kind # Content (wt%) DMT TMG EG Kind content (mol%) Reducing viscosity (nsp / c) Tm (° C) Example 22 100 74 26 DDO 4.9 0.82 188 C 丨 〇-Na 2.5 Example 23 100 70 30 DDO 16.0 0.85 168 Cs-Li 1.5 Example 24 100 70 30 DDO 16.0 0.85 168 C8-Na 2.5 Example 25 100 92 8 DDO 49.5 0.85 120 C6-Na 2.5 Comparative Example 12 100 70 30 DDO 16.0 0.85 168 C8-Na 5.2 Comparative Example 13 100 96 4 DDO 4.4 0.82 214 C8-Na 2.5 Example 26 100 40 60 PTMG 7.9 1.21 171 C8 -Na 2.5 Example 27 100 62 38 PTMG 8.6 1.29 171 C6-Na 1.5 Example 28 100 88 12 PTMG 19.2 1.78 170 C6-Na 2.0 Comparative Example 1 4 100 88 12 PTMG 19.2 1.78 170 C6-Na 0.4 Comparative Example 1 5 100 40 60 PTMG 7.9 1.21 171 C6-Na 5.3 Example 29 100 30 70 DiA 14.9 0.75 171 C i 〇- N a 2.0 Example 30 100 54 46 DiA 16.0 0.76 158 C6-Na 1.5 Comparative Example 1 6 100 3 97 DiA 15.5 0.836 218 C 16-N a 3.0 Comparative Example 17 100 30 70 DiA 14.9 0.75 170--* C6-Na: Sodium hexanoate (Tm: 23 7 ° C) C8-Na: Sodium (Tm: 249 ° C) C10-Na: Sodium caprate (Tm: 251 ° C) C16-Na: Sodium palmitate (Tm: 257 ° C) C8-Li: Lithium octoate (Tm: 267 ° C) -27- 583215 V. Description of the invention (26) Table 6 Sheet characteristics Reduction viscosity (ηδρ / c) Haze 1% * Elasticity (MPa) Crystallization index Xc (%) H1 H2 Example 22 0.74 0.8 0.5 1220 26.1 Example Resin Example 4 4 0.71 1.1 0.8 191 29.2 Resin Example 8 Example 24 0.76 1.1 0.7 194 30.7 Resin Example 8 Example 25 0.68 0.8 0.3 53 19.2 Resin Example 10 Example 2 2 0.41----No flake comparison Example 1 3 0.73 21.2 18.3 1510 33.3 Resin Example 2 of Comparative Example 26 0.99 Surface 2.9 140 28.3 No flakes could be made without metal oxides Example 27 1.10 11.6 3.8 138 28.1 Example 28 1.52 11.9 7.6 98 20.8 Comparative Example 14 1.69 11.9 11.8 90 18.1 Comparative Example 15 0.54----Example of flakes that cannot be produced 29 0.71-3.1 1 16 23.2 Example of flakes that cannot be produced without metal oxides 30 0.73 10.7 2.8 106 23.3 Comparative example 1 6 0.829----Blocking comparison Example 17 0.74---Occlusion * H1: No metal salt compound, H 2: Metal salt-containing compound -28-583215 V. Description of the invention (27) • [Effect of the invention] The transparent and soft polyester-based copolyester formed by the hard segment and the soft segment of the present invention is a transparent and soft main component Polyester, melt-molding of this transparent polyester, the characteristics of the unstretched flakes produced are less than 1 500 MPa, the crystallization index Xc measured by wide-angle X-ray is greater than 5%, and the haze of the flakes ( ΙΟΟμπι conversion) is less than 15%, and it has excellent transparency, softness, and handling properties that cannot be achieved since ancient times. Therefore, it can be used in a wide range of applications such as sheet, film, machine plastics, tubes, packaging bags, skins, and stationery molded articles. In addition, in the present invention, in addition to using a transparent soft polyester alone as a molded product, it can be 'laminated with a substance whose flexibility is changed by the transparent polyester of the present invention' or with polyolefins such as polyethylene and polypropylene, and polyesters. , Polycarboxylate, vinyl chloride, and other resins are laminated and blended to maintain the effects of the present invention such as transparency, flexibility, and occlusion, and may provide other functions. -29-

Claims (1)

5 Lai 6. Patent Application No. 9 1 1 05604 "Transparent Soft Polyester" Patent Case (Amended on April 8, 1992) VI. Application Patent Scope: 1. A transparent soft polyester, which is characterized by 99 ~ 40 Mo The copolyester formed by the hard segment of 1% and the soft segment of 1 ~ 60mol% is a transparent soft polyester whose main component is the elasticity of the unstretched sheet obtained by melt molding of this transparent soft polyester It is 18 to 1,500 MPa, the crystallization index Xc measured by wide-angle X-ray is 5 to 33%, and the haze of the sheet (converted to 100 μm) is 0 to 15%. 2. The transparent soft polyester according to item 1 of the scope of patent application, wherein 70 to 100 mole% of the dicarboxylic acid component constituting the hard segment is 1 or more selected from terephthalic acid (TPA), 2, 6- Naphthalenedicarboxylic acid (NDA), 4,4'-biphenyldicarboxylic acid (BPA). 3. The transparent and soft polyester according to item 1 or 2 of the scope of the patent application, wherein the diol component constituting the hard segment contains 1,4-butanediol (TMO) and ethylene glycol (EG), and is relative to the composition The composition ratio of the total diol component in the hard segment is 20 to 95 mole% TMG and 5 to 80 mole% EG. 4. The transparent soft polyester according to item 1 of the scope of the patent application, wherein the soft component constituting the soft segment is 1 or more selected from long-chain aliphatic dicarboxylic acids having a number average molecular weight of 100 to 1,000, and the amount Long chain aliphatic diols having an average molecular weight of 100 to 1,000, and polyalkylene oxide diols having a number average molecular weight of 500 to 4,000. 5. The transparent soft polyester 'according to item 1 of the scope of patent application, wherein the soft chain is composed of 583215 6. The soft component in the scope of patent application is dimer diol (DDO). 6. The transparent and soft polyester according to item 1 of the scope of patent application, which contains 0.5 to 5.0% by weight of a metal element, and this metal element is a group containing metal elements of Group I-a or Group II-a of the periodic table. Metal salt compounds. -2 -