Propylene glycol monomethyl ether acetate composition

Abstract

A propylene glycol monomethyl ether acetate composition containing propylene glycol 1-monomethyl ether 2-acetate, acetic acid, propionic acid, and water, in which the content of the propionic acid is 2-30 ppm (inclusive) per 100 mass% of the propylene glycol monomethyl ether acetate composition, and the content of the acetic acid is 5-30 ppm (inclusive) per 100 mass% of the propylene glycol monomethyl ether acetate composition. The sum of the content of the acetic acid and the content of the propionic acid is 5 ppm to 80 ppm inclusive, and the content of the water is 17 ppm to 250 ppm inclusive relative to 100 mass% of the propylene glycol monomethyl ether acetate composition.

Description

Technical Field

[0001] The present invention relates to propylene glycol monomethyl ether acetate compositions. Background Art

[0002] Propylene glycol monomethyl ether acetate (hereinafter also referred to as "PMA") is known as an organic solvent used in various applications. PMA is produced, for example, by a direct esterification reaction of propylene glycol monomethyl ether (hereinafter also referred to as "PM") with acetic acid under predetermined conditions (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: China Patent Application Publication No. 1515537 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] PMA obtained by the method described in Patent Document 1 was stored for a long period of time and its composition was confirmed. As a result, it was found that the purity of PMA tended to decrease.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a propylene glycol monomethyl ether acetate composition having excellent storage stability.

[0009] Methods used to solve problems

[0010] The present inventors have found that a propylene glycol monomethyl ether acetate composition containing prescribed components can solve the above-mentioned problems, thereby completing the present invention.

[0011] That is, the present invention includes the following aspects.

[0012] [1] A propylene glycol monomethyl ether acetate composition comprising propylene glycol 1-monomethyl ether 2-acetate, acetic acid, propionic acid, and water, wherein:

[0013] The content of the propionic acid is 2 ppm or more and 30 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

[0014] The sum of the contents of the acetic acid and the propionic acid is 5 ppm or more and 80 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition,

[0015] The water content is 17 ppm or more and 250 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

[0016] [2] The propylene glycol monomethyl ether acetate composition according to [1], wherein the content of propylene glycol monomethyl ether is 4.0 ppm or less relative to 100% by mass of the propylene glycol monomethyl ether acetate composition.

[0017] [3] The propylene glycol monomethyl ether acetate composition according to [1] or [2], wherein the water content is 20 ppm or more and 100 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

[0018] [4] The propylene glycol monomethyl ether acetate composition according to any one of [1] to [3], wherein when the propylene glycol monomethyl ether acetate composition is subjected to the following test and then subjected to gas chromatography analysis under the following conditions, when the relative retention time of the peak of propylene glycol 1-monomethyl ether 2-acetate is set to 1.00, the area fraction of the peak appearing in the range of relative retention time of 0.64 to 0.72 is 800 ppm or less.

[0019] (test)

[0020] The propylene glycol monomethyl ether acetate composition was heated to 80° C. in a borosilicate glass container under a nitrogen atmosphere and maintained for 5 days.

[0021] (Gas chromatography analysis conditions)

[0022] Analytical column: The stationary phase is polyethylene glycol, length 30m × inner diameter 0.25mm × film thickness 0.25μm

[0023] Heating conditions: Keep at 50°C for 10 minutes, then increase the temperature to 250°C at 5°C / min

[0024] Sample introduction temperature: 250℃

[0025] Carrier gas: nitrogen

[0026] Column gas flow rate: 1.0 mL / min

[0027] Detector and detection temperature: hydrogen flame ionization detector, 250℃

[0028] Control mode: Column flow

[0029] Split ratio: 50:1

[0030] Injection volume: 2.0 μL

[0031] Effects of the Invention

[0032] According to the present invention, a propylene glycol monomethyl ether acetate composition having excellent storage stability can be provided. DETAILED DESCRIPTION

[0033] Hereinafter, a method for implementing the present invention (hereinafter referred to as "this embodiment") will be described in detail. This embodiment is an illustration for illustrating the present invention and is not intended to limit the present invention to the following. The present invention can be implemented by appropriately changing it within the scope of its purpose.

[0034] <Propylene glycol monomethyl ether acetate composition>

[0035] The propylene glycol monomethyl ether acetate composition (hereinafter also referred to as the "PMA composition") of this embodiment contains propylene glycol 1-monomethyl ether 2-acetate (hereinafter also referred to as "PGMEA"), acetic acid, propionic acid, and water. The content of the propionic acid is from 2 ppm to 30 ppm per 100 mass % of the propylene glycol monomethyl ether acetate composition, the sum of the contents of the acetic acid and the propionic acid is from 5 ppm to 80 ppm per 100 mass % of the propylene glycol monomethyl ether acetate composition, and the content of water is from 17 ppm to 250 ppm per 100 mass % of the propylene glycol monomethyl ether acetate composition. Due to this configuration, the PMA composition of this embodiment has excellent storage stability.

[0036] The reason why the PMA composition of the present embodiment is excellent in storage stability is presumed to be as follows, but the reason is not necessarily clear and is not intended to be limiting.

[0037] The decomposition of PGMEA and the generation of impurities during long-term storage of propylene glycol monomethyl ether acetate compositions are believed to be one of the factors affecting storage stability. Hydrolysis is an example of a cause of the decomposition of carboxylic acid esters such as PGMEA. Typically, in the presence of acid and water, carboxylic acid esters hydrolyze to form carboxylic acids and alcohols. Furthermore, it is believed that carboxylic acid esters tend to hydrolyze more easily when the acid content is high. However, by keeping the propionic acid content, the sum of the acetic acid content and the propionic acid content, and the water content in the PMA composition of this embodiment within the above-mentioned ranges, it is believed that the transesterification of alcohols that may be generated by the hydrolysis of PGMEA with the acetyl groups of PGMEA can be suppressed. This result is different from the above-mentioned tendency, and the hydrolysis of PGMEA is suppressed.

[0038] However, the above reason is considered to be only one factor that contributes to the excellent storage stability of the PMA composition of the present embodiment, and the mechanism of action of the present embodiment is not limited thereto.

[0039] The use of the PMA composition of this embodiment is not particularly limited, and can be used for industrial applications such as inks, diluents, pharmaceuticals / agrichemicals, plasticizers, surfactants, polymer materials, lubricants, adhesives, cleaning agents, electronic materials, and coatings.

[0040] The electronic material is not particularly limited, and examples thereof include liquid crystal displays (LCDs) and semiconductor devices. The PMA composition of this embodiment is preferably used in the production of semiconductor devices because it has excellent storage stability.

[0041] Specific examples of applications related to semiconductor device manufacturing include, but are not particularly limited to, cleaning solutions (e.g., treatment solutions for cleaning substrate surfaces after resist stripping), pre-wetting solutions (e.g., treatment solutions used before resist coating to reduce resist solvent consumption), resist solvents (e.g., treatment solutions for dissolving photosensitive agents and resins), developers (e.g., treatment solutions for removing soluble resins after negative resist exposure), stripping solutions (e.g., treatment solutions for removing cured resist after etching), etc. From the perspective of preventing product defects in semiconductor device manufacturing, the PMA composition of this embodiment is preferably used as a resist solvent, pre-wetting solution, solvents for edge rinsing (rinsing for removing resist from the outer periphery of the wafer) and backside rinsing (rinsing for removing resist from the backside of the wafer) used when applying resist, developers used when developing negative resists, rinse solutions used for rinsing after negative resist development, and cleaning solutions or rinse solutions for removing resist after etching.

[0042] (Propylene glycol 1-monomethyl ether 2-acetate)

[0043] Propylene glycol 1-monomethyl ether 2-acetate in the PMA composition of the present embodiment can be identified and quantified by, for example, the following gas chromatography (hereinafter also referred to as "GC") analysis.

[0044] (Gas chromatography analysis)

[0045] Analytical column: The stationary phase is polyethylene glycol, length 30m × inner diameter 0.25mm × film thickness 0.25μm

[0046] Heating conditions: Keep at 50°C for 10 minutes, then increase the temperature to 250°C at 5°C / min

[0047] Sample introduction temperature: 250℃

[0048] Carrier gas: nitrogen

[0049] Column gas flow rate: 1.0 mL / min

[0050] Detector and detection temperature: hydrogen flame ionization detector, 250℃

[0051] Control mode: Column flow

[0052] Split ratio: 50:1

[0053] Injection volume: 2.0 μL

[0054] The content of PGMEA in the PMA composition of this embodiment can be appropriately determined depending on the intended use of the PMA composition of this embodiment and is not particularly limited. However, from the perspective of applications requiring high purity, the PGMEA content is preferably 99.94% or greater, more preferably 99.95% or greater, and even more preferably 99.96% or greater, as measured by the peak area ratio relative to the total peak area of ​​the spectrum obtained from GC analysis. In this embodiment, "total peak area" refers to the sum of the areas of all peaks appearing in the spectrum obtained from GC analysis. In this embodiment, "all peaks" can be specifically defined as all peaks appearing when analysis is continued from a relative retention time of 0.14 to 2.95, with the relative retention time of the PGMEA peak being 1.00, and then stopped.

[0055] (acetic acid)

[0056] The PMA composition of this embodiment contains acetic acid. From the perspective of storage stability, the content of acetic acid in the PMA composition of this embodiment is preferably 3 ppm to 78 ppm, more preferably 5 ppm to 72 ppm, and even more preferably 7 ppm to 69 ppm, relative to 100 mass % of the PMA composition of this embodiment.

[0057] The above content can be measured according to the method described in the Examples below.

[0058] The above content can be adjusted to the above range by, for example, appropriately adding acetic acid after the adsorption treatment described below. Furthermore, the above content can also be adjusted to the above range by, for example, appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and the dehydration treatment.

[0059] (Propionic acid)

[0060] The PMA composition of this embodiment contains propionic acid. From the perspective of storage stability, the content of propionic acid in the PMA composition of this embodiment is 2 ppm to 30 ppm, preferably 3 ppm to 25 ppm, and more preferably 3 ppm to 20 ppm, relative to 100 mass % of the PMA composition of this embodiment.

[0061] The above content can be measured according to the method described in the Examples below.

[0062] The above content can be adjusted to the above range by, for example, appropriately adding propionic acid after the adsorption treatment described below. Furthermore, the above content can also be adjusted to the above range by, for example, appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and the dehydration treatment.

[0063] (The sum of acetic acid and propionic acid content)

[0064] In the present embodiment, from the viewpoint of storage stability, the sum of the contents of acetic acid and propionic acid in the PMA composition of the present embodiment is 5 ppm or more and 80 ppm or less, preferably 8 ppm or more and 75 ppm or less, and more preferably 10 ppm or more and 72 ppm or less, relative to 100 mass % of the PMA composition of the present embodiment.

[0065] The above content can be measured according to the method described in the Examples below.

[0066] The above content can be adjusted to within the above range by, for example, appropriately adding acetic acid and / or propionic acid after the adsorption treatment described below. Furthermore, the above content can also be adjusted to within the above range by, for example, appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and the dehydration treatment.

[0067] (water)

[0068] The PMA composition of this embodiment contains water. From the perspective of storage stability, the water content in the PMA composition of this embodiment is 17 ppm to 250 ppm, preferably 18 ppm to 200 ppm, and more preferably 20 ppm to 100 ppm, relative to 100 mass % of the PMA composition of this embodiment.

[0069] The above content can be measured according to the method described in the Examples below.

[0070] The above content can be adjusted to the above range by, for example, adding water after the dehydration treatment described below. Furthermore, the above content can also be adjusted to the above range by, for example, appropriately changing the dehydration treatment conditions (for example, treatment time, etc.).

[0071] (PM)

[0072] The PMA composition of this embodiment may also contain propylene glycol monomethyl ether (PM). Since PM tends to undergo intramolecular dehydration reactions in the presence of acid, which can affect the storage stability of the PMA composition, its content is preferably low. Specifically, from the perspective of storage stability, the PM content in the PMA composition of this embodiment is preferably 4.0 ppm or less, and more preferably below the detection limit (2 ppm or less in GC analysis), relative to 100% by mass of the PMA composition of this embodiment.

[0073] The above content can be measured according to the method described in the Examples below.

[0074] The above-mentioned content can be adjusted to the above-mentioned range, for example, by azeotropic dehydration after esterification, followed by distillation purification, adsorption treatment, etc. In particular, the above-mentioned content can be controlled by appropriately selecting an adsorbent in the adsorption treatment (step (c) described later). In this embodiment, various ion exchange resins such as KYOWA AD500 (registered trademark) manufactured by Kyowa Chemical Industry Co., Ltd. and ORLITE DS-6 manufactured by Organo Co., Ltd. can be used as the adsorbent. For example, compared with the case of using a conventional inorganic synthetic adsorbent, the case of using a weakly alkaline ion exchange resin has a tendency to further reduce the amount of PM, and therefore it is preferred to use a weakly alkaline ion exchange resin such as ORLITE DS-6 manufactured by Organo Co., Ltd. to implement the adsorption treatment.

[0075] (ingredient A)

[0076] From the viewpoint of storage stability, when the PMA composition of the present embodiment is subjected to the following test and then subjected to the above-mentioned GC analysis, the area ratio of the peak appearing within the relative retention time range of 0.64 to 0.72 (the substance corresponding to this peak will also be referred to as "Component A"), with the relative retention time of the propylene glycol 1-monomethyl ether 2-acetate peak being set to 1.00, is preferably 800 ppm or less, more preferably 700 ppm or less, and even more preferably 600 ppm or less.

[0077] (test)

[0078] The propylene glycol monomethyl ether acetate composition was heated to 80° C. in a borosilicate glass container under a nitrogen atmosphere and maintained for 5 days.

[0079] The above-mentioned area ratio can be measured according to the method described in Examples below.

[0080] The above-mentioned area ratio can be adjusted to within the above-mentioned range, for example, by appropriately adding acetic acid, propionic acid, and / or water after the adsorption treatment and / or dehydration treatment described below. Furthermore, the above-mentioned area ratio can also be adjusted to within the above-mentioned range, for example, by appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and / or dehydration treatment.

[0081] (ethyl acetate)

[0082] From the viewpoint of storage stability, when the PMA composition of this embodiment is subjected to the above test and then to the above GC analysis, the area ratio of the ethyl acetate peak is preferably 120 ppm or less, more preferably 100 ppm or less, and even more preferably 70 ppm or less.

[0083] The above-mentioned area ratio can be measured according to the method described in Examples below.

[0084] The above-mentioned area ratio can be adjusted to within the above-mentioned range, for example, by appropriately adding acetic acid, propionic acid, and / or water after the adsorption treatment and / or dehydration treatment described below. Furthermore, the above-mentioned area ratio can also be adjusted to within the above-mentioned range, for example, by appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and / or dehydration treatment.

[0085] (Ingredient B)

[0086] From the viewpoint of storage stability, when the PMA composition of the present embodiment is subjected to the above-described test and then subjected to the above-described GC analysis, with the relative retention time of the propylene glycol 1-monomethyl ether 2-acetate peak being set to 1.00, the area ratio of the peak appearing within the range of relative retention times of 0.37 to 0.44 (the substance corresponding to this peak will also be referred to as "Component B") is preferably 70 ppm or less, more preferably 65 ppm or less, and even more preferably 60 ppm or less.

[0087] The above-mentioned area ratio can be measured according to the method described in Examples below.

[0088] The above-mentioned area ratio can be adjusted to within the above-mentioned range, for example, by appropriately adding acetic acid, propionic acid, and / or water after the adsorption treatment and / or dehydration treatment described below. Furthermore, the above-mentioned area ratio can also be adjusted to within the above-mentioned range, for example, by appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and / or dehydration treatment.

[0089] (2-Acetoxy-1-propanol)

[0090] From the viewpoint of storage stability, when the PMA composition of the present embodiment is subjected to the above test and then to the above GC analysis, the area ratio of the 2-acetoxy-1-propanol peak is preferably 240 ppm or less, more preferably 200 ppm or less, and even more preferably 150 ppm or less.

[0091] The above-mentioned area ratio can be measured according to the method described in Examples below.

[0092] The above-mentioned area ratio can be adjusted to within the above-mentioned range, for example, by appropriately adding acetic acid, propionic acid, and / or water after the adsorption treatment and / or dehydration treatment described below. Furthermore, the above-mentioned area ratio can also be adjusted to within the above-mentioned range, for example, by appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and / or dehydration treatment.

[0093] From the viewpoint of storage stability, when the PMA composition of the present embodiment is subjected to the above-mentioned test and then subjected to the above-mentioned GC analysis, the area ratio of the PGMEA peak is preferably 99.80% or more of the total peak area, more preferably 99.82% or more, and even more preferably 99.85% or more.

[0094] The above-mentioned area ratio can be measured according to the method described in Examples below.

[0095] The above-mentioned area ratio can be adjusted to within the above-mentioned range, for example, by appropriately adding acetic acid, propionic acid, and / or water after the adsorption treatment and / or dehydration treatment described below. Furthermore, the above-mentioned area ratio can also be adjusted to within the above-mentioned range, for example, by appropriately changing the conditions (e.g., treatment time) of the adsorption treatment and / or dehydration treatment.

[0096] <Method for producing PMA composition>

[0097] The method for producing the PMA composition of this embodiment is not particularly limited, but is preferably the following method (hereinafter also referred to as "Production Method A"). Production Method A preferably includes: step (a) of obtaining a first product containing PGMEA; step (b) of distilling the first product to obtain a second product; step (c) of subjecting the organic acid contained in the second product to an adsorption treatment to obtain a third product; step (d) of desalting the third product to obtain a fourth product; and step (e) of subjecting the fourth product to a dehydration treatment to obtain a PMA composition. The amounts of acetic acid, propionic acid, and water in the PMA composition can be adjusted in steps (c) and (e), and the method may further include step (f) of adding acetic acid, propionic acid, and / or water to the product obtained in step (e) to obtain a PMA composition.

[0098] (Step (a))

[0099] In step (a), a first product containing PGMEA is obtained. Step (a) may include an operation for producing PGMEA based on a conventionally known method. The method for producing PGMEA is not particularly limited, and examples thereof include the method described in Chinese Patent Application Publication No. 1515537. Specifically, it can be produced by, for example, a direct esterification reaction of PM with acetic acid. The first product may also contain raw materials, catalysts, by-products, etc. that may be used in the reaction for producing PGMEA.

[0100] (Step (b))

[0101] In step (b), the first product is distilled to obtain the second product. There is no particular limitation on the specific operation of distillation, and examples include atmospheric distillation, reduced pressure distillation, and the like. The distillation can also be repeated. This step can remove the raw materials, catalysts, by-products, and the like that may be used in the reaction for producing PGMEA that may be contained in the first product. There are no particular limitations on the conditions for distillation, and for example, reference may be made to the conditions described in Chinese Patent Application Publication No. 1515537 for implementation. Based on the second product as 100% by mass, the amounts of PM, acetic acid, propionic acid, and water that may be contained in the second product may exceed 4 ppm, exceed 78 ppm, exceed 30 ppm, and exceed 250 ppm, respectively.

[0102] (Step (c))

[0103] In step (c), the second product is subjected to an adsorption treatment to obtain a third product. The conditions for the adsorption treatment are preferably those that can reduce the amounts of acetic acid and propionic acid contained in the second product, but are not particularly limited. Examples include adsorption treatment using ORLITE DS-6 manufactured by Organo Corporation. In this case, the amounts of PM, acetic acid, and propionic acid that may be contained in the third product can be adjusted, for example, by adjusting the amount of ORLITE DS-6 used, the treatment time, and the like. The adsorbent, such as ORLITE DS-6, used in the adsorption treatment can be removed by filtration using a PTFE (polytetrafluoroethylene) membrane filter or the like.

[0104] (Step (d))

[0105] In step (d), the third product is subjected to a desalting treatment to obtain a fourth product. The specific operation of the desalting treatment is not particularly limited, and examples thereof include flash evaporation or water washing, and the treatment may be repeated. This step can remove various amine salts and inorganic salts that may be contained in the third product. The flash evaporation conditions are not particularly limited, and for example, the third product can be supplied to a flash tank having a reduced pressure (absolute pressure in the system during distillation, the same below) of 2.5 to 3.5 kPa and heated to about 65 to 75°C at a linear velocity (LV) of 55 to 65 m / hour.

[0106] (Step (e))

[0107] In step (e), the fourth product is subjected to a dehydration treatment to obtain a PMA composition. The dehydration treatment conditions are preferably those that can reduce the amount of water contained in the fourth product, but are not particularly limited. Examples include dehydration treatment using nitrogen bubbling. The amount of water contained in the PMA composition can be adjusted, for example, by adjusting the treatment time.

[0108] (Step (f))

[0109] In step (f), acetic acid, propionic acid, and / or water may be added to the product obtained in step (e) to adjust the amount of acetic acid, propionic acid, and / or water in the PMA composition. The amount of acetic acid, propionic acid, and / or water added is not particularly limited and can be determined, for example, based on the difference between the desired acetic acid content C1, propionic acid content C2, and water content C3 in the PMA composition and the acetic acid content C1', propionic acid content C2', and water content C3' in the product obtained in step (e). These contents can be measured according to the methods described in the Examples below.

[0110] Example

[0111] Hereinafter, this embodiment will be described in further detail based on examples, but this embodiment is not limited to these examples.

[0112] [Example 1]

[0113] (Step (a))

[0114] The first product containing PGMEA was synthesized by referring to the method described in Chinese Patent Application Publication No. 1515537. That is, the first product containing PGMEA was obtained by a direct esterification reaction of PM with acetic acid.

[0115] (Step (b))

[0116] Next, the first product containing PGMEA is introduced into a distillation column and subjected to atmospheric distillation. Specifically, the reflux ratio is set to 1 to 9, and unreacted raw materials and the like are first distilled off, followed by recovery of the PGMEA-containing fraction.

[0117] Next, the PGMEA-containing fraction obtained by atmospheric distillation was introduced into a distillation column and subjected to reduced-pressure distillation. Specifically, the vacuum within the distillation column was set to 21.3 kPa, the temperature within the column was controlled to below 110°C, and the reflux ratio was set to 1 to 6. The fraction at the top of the column (temperature 98-100°C) was recovered as the second product. Based on 100% by mass of the second product, the amounts of PM, acetic acid, propionic acid, and water in the resulting second product were below the detection limit (below the detection limit in GC analysis), 90 ppm, 50 ppm, and 300 ppm, respectively.

[0118] The contents of PM, acetic acid, propionic acid, and water in the second product, as well as the contents of PGMEA, PM, acetic acid, propionic acid, and water in the PMA composition described in Example 1, were determined by the following methods. Specifically, the water content was measured using a Karl Fischer titrator (product name "AQ-2200A," manufactured by Hiranuma Co., Ltd., Karl Fischer coulometric titration). The contents of PGMEA, PM, acetic acid, and propionic acid were measured by GC analysis under the following conditions.

[0119] (Gas chromatography analysis)

[0120] Analyzer: Nexis GC-2030 manufactured by Shimadzu Corporation

[0121] Analytical column: DB-WAX manufactured by Agilent Technologies (column with polyethylene glycol as the stationary phase, length 30 m × inner diameter 0.25 mm × film thickness 0.25 μm)

[0122] Heating conditions: Keep at 50°C for 10 minutes, then increase the temperature to 250°C at 5°C / min

[0123] Sample introduction temperature: 250℃

[0124] Carrier gas: nitrogen

[0125] Column gas flow rate: 1.0 mL / min

[0126] Detector and detection temperature: hydrogen flame ionization detector, 250℃

[0127] Control mode: Column flow

[0128] Split ratio: 50:1

[0129] Injection volume: 2.0 μL

[0130] In the above GC analysis, the PGMEA content was calculated as the peak area percentage of PGMEA relative to the total peak area in the spectrum obtained from the GC analysis. The PM content was calculated as the peak area percentage of PM relative to the total peak area in the spectrum obtained from the GC analysis. Furthermore, the acetic acid and propionic acid contents were calculated by GC analysis using the absolute calibration curve method.

[0131] (Step (c))

[0132] To the second product obtained above (100% by volume), 5.0% by volume of ORLITE DS-6 manufactured by Organo Corporation was added, and the mixture was stirred for 30 minutes to remove acetic acid and propionic acid by adsorption. The mixture was then filtered using a PTFE membrane filter manufactured by ADVANTEC (Model: T020A047A, pore size: 0.20 μm) to obtain a third product.

[0133] (Step (d))

[0134] Next, the third product was introduced into a distillation column and flashed. Specifically, the third product was fed at a linear velocity (LV) of 59 m / hour into a flash tank heated to approximately 70°C and having a reduced pressure of 3 kPa. 90% by mass (relative to 100% by mass of the third product) of the product was distilled from the top of the flash tank, resulting in the fourth product.

[0135] (Step (e))

[0136] Nitrogen gas was bubbled through the fourth product at 3-5 L / min for 110 minutes through a Kinoshita-type spherical filter (model: 501G-1, filter diameter: 10 mm, filter pore size: 100-120 μm) manufactured by Kinoshita Chemical Industry to dehydrate it, yielding the PMA composition of Example 1. The resulting PMA composition was subjected to GC analysis and moisture analysis under the same conditions as above. Based on 100% by mass of the PMA composition, the amounts of PGMEA, PM, acetic acid, propionic acid, and water in the PMA composition were 99.966% by area, below the detection limit, 10 ppm, 5 ppm, and 20 ppm, respectively. Details of the analytical results are shown in Table 1.

[0137] In the following Examples and Comparative Examples, the amounts of PGMEA, PM, acetic acid, propionic acid, and water in the PMA composition were confirmed in the same manner as described above.

[0138] Next, the PMA composition was subjected to the following test: the PMA composition was placed in a 110 mL borosilicate glass container, sealed with nitrogen, and then heated using a thermostat (product name "ST-110B1", manufactured by ESPEC) and maintained at 80°C for 5 days.

[0139] The PMA composition after the above test was subjected to GC analysis under the above conditions.

[0140] By comparing GC Spectrum A obtained by GC analysis before the test with GC Spectrum B obtained by GC analysis after the test, substances with a peak area ratio of less than 5 ppm in Spectrum A and a peak area ratio of 5 ppm or more in Spectrum B were identified as substances significantly affecting the storage stability of the PMA composition, and their amounts were evaluated. Specifically, in GC Spectrum B, when the relative retention time of the propylene glycol 1-monomethyl ether 2-acetate peak is set to 1.00, the area ratios of the peak appearing within the relative retention time range of 0.64 to 0.72 and the area ratios of the peak appearing within the relative retention time range of 0.37 to 0.44 are 567.6 area ppm and 53.1 area ppm, respectively. Furthermore, in GC Spectrum B, the area ratios of the ethyl acetate peak and the 2-acetoxy-1-propanol peak are 51.7 area ppm and 126.8 area ppm, respectively. Furthermore, in GC chromatogram A, the peak corresponding to propylene glycol monomethyl ether (PM) in the relative retention time range of 0.62 to 0.64 was below the detection limit (2 ppm or less).

[0141] (Example 2)

[0142] A PMA composition of Example 2 was obtained in the same manner as in Example 1, except that 4.0% by volume of ORLITE DS-6 manufactured by Organo Corporation was added to the second product (100% by volume) of step (c) of Example 1, and nitrogen was bubbled through the fourth product of step (e) at the aforementioned supply rate for 105 minutes. This PMA composition was subjected to the same test as in Example 1 and then analyzed by the same gas chromatography method as in Example 1. Details of the analytical results are shown in Table 1.

[0143] (Example 3)

[0144] A PMA composition of Example 3 was obtained in the same manner as in Example 1, except that 5.1% by volume of ORLITE DS-6 manufactured by Organo Corporation was added to the second product (100% by volume) of step (c) of Example 1, and nitrogen was bubbled through the fourth product of step (e) at the aforementioned supply rate for 90 minutes. This PMA composition was subjected to the same test as in Example 1 and then analyzed by the same gas chromatography method as in Example 1. Details of the analytical results are shown in Table 1.

[0145] (Example 4)

[0146] A PMA composition of Example 4 was obtained in the same manner as in Example 1, except that 3.4% by volume of ORLITE DS-6 manufactured by Organo Corporation was added to the second product (100% by volume) of step (c) of Example 1, and nitrogen was bubbled through the fourth product of step (e) at the aforementioned supply rate for 80 minutes. This PMA composition was subjected to the same test as in Example 1 and then analyzed by the same gas chromatography method as in Example 1. Details of the analytical results are shown in Table 1.

[0147] (Example 5)

[0148] A PMA composition of Example 5 was obtained in the same manner as in Example 1, except that 2.5% by volume of ORLITE DS-6 manufactured by Organo Corporation was added to the second product (100% by volume) of step (c) of Example 1, and nitrogen was bubbled through the fourth product of step (e) at the aforementioned supply rate for 80 minutes. This PMA composition was subjected to the same test as in Example 1 and then analyzed by the same gas chromatography method as in Example 1. Details of the analytical results are shown in Table 1.

[0149] (Comparative Example 1)

[0150] A PMA composition of Comparative Example 1 was obtained in the same manner as in Example 1, except that 5.0% by volume of ORLITE DS-6 manufactured by Organo Corporation was added to the second product (100% by volume) of step (c) in Example 1, and nitrogen was bubbled through the fourth product of step (e) at the aforementioned supply rate for 115 minutes. This PMA composition was subjected to the same test as in Example 1 and then analyzed by the same gas chromatography method as in Example 1. Details of the analytical results are shown in Table 1.

[0151]

Claims

1. A propylene glycol monomethyl ether acetate composition, comprising propylene glycol 1-monomethyl ether 2-acetate, acetic acid, propionic acid and water, wherein: The content of the propionic acid is 2 ppm or more and 30 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition, The sum of the contents of the acetic acid and the propionic acid is 5 ppm or more and 80 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition, The water content is 17 ppm or more and 250 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

2. The propylene glycol monomethyl ether acetate composition according to claim 1, wherein The content of propylene glycol monomethyl ether is 4.0 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

3. The propylene glycol monomethyl ether acetate composition according to claim 1 or 2, wherein The water content is 20 ppm or more and 100 ppm or less relative to 100 mass % of the propylene glycol monomethyl ether acetate composition.

4. The propylene glycol monomethyl ether acetate composition according to claim 1 or 2, wherein When the propylene glycol monomethyl ether acetate composition was subjected to the following test and then subjected to gas chromatography analysis under the following conditions, the area fraction of the peak appearing in the range of relative retention times of 0.64 to 0.72, with the relative retention time of the propylene glycol 1-monomethyl ether 2-acetate peak being set to 1.00, was 800 ppm or less. (test) The propylene glycol monomethyl ether acetate composition was heated to 80° C. in a borosilicate glass container under a nitrogen atmosphere and maintained for 5 days. (Gas chromatography analysis conditions) Analytical column: The stationary phase is polyethylene glycol, length 30m × inner diameter 0.25mm × film thickness 0.25μm; Heating conditions: maintain at 50°C for 10 minutes, then increase the temperature to 250°C at 5°C / min; Sample introduction temperature: 250℃; Carrier gas: nitrogen; Column gas flow rate: 1.0 mL / min; Detector and detection temperature: hydrogen flame ionization detector, 250 ° C; Control mode: column flow; Split ratio: 50:1; Injection volume: 2.0 μL.

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