Surface treatment method for container, and surface structure of container treated by said method

Abstract

Provided is a glass container having extremely excellent chemical durability. According to the present invention, a cleaning step for cleaning an inner surface of a glass container with a cleaning liquid composed of water, an acid aqueous solution, a surfactant aqueous solution, or an acid aqueous solution to which a surfactant is added, and a distortion removing step for removing distortion by heating and raising the temperature of the glass container cleaned in the cleaning step and then cooling the same are performed. Subsequently, the glass container is disposed in a plasma treatment device, a film-forming surface of the glass container is modified and hydrophilized in a plasma atmosphere formed by a plasma generating part, in a state in which an evaporation source for imparting a hydrophilic group is supplied into a vacuum chamber having a predetermined degree of vacuum in the plasma treatment device, an evaporation source of a precursor material of a SAM film or a self-assembled multilayer film is supplied to the glass container having the hydrophilized film-forming surface, in a state in which an evaporation source for promoting a hydrolysis or nucleophilic reaction of the precursor material of the SAM film or the self-assembled multilayer film is supplied into the vacuum chamber having a predetermined degree of vacuum, a SAM film or a self-assembled multilayer film is formed on the hydrophilized film-forming surface, and finally, bonding in the film-forming surface and the SAM film or the self-assembled multilayer film in the vacuum chamber having a predetermined degree of vacuum is strengthened.

Description

Container surface treatment method and surface structure of container treated by said method

[0001] The present invention relates to a method for treating the surface of pharmaceutical and lab containers such as ampoules and tube bottles, and to the surface structure of containers treated by said method.

[0002] Medical containers filled with medicinal solutions, blood, etc., require transparency to allow detection of contamination by foreign matter or changes due to drug compounding, heat resistance to withstand sterilization and other processes, flexibility to facilitate discharge of medicinal solutions, gas barrier properties to prevent deterioration of the quality of medicinal solutions, etc. due to the intrusion of water vapor or oxygen into the container, and reduction of elution of trace substances from the container surface. Furthermore, heat sterilization is generally performed after filling these containers with the contents. In particular, infusion preparations, etc. that are administered directly into the bloodstream, require strict maintenance of a sterile state, and sterilization at 121°C is becoming the global standard.

[0003] Conventionally, glass containers have been used as such medical containers, but due to problems such as container breakage due to impact or dropping, plastic containers, which have excellent impact resistance, are also being used.

[0004] Glass containers such as ampoules and tube bottles are often manufactured by heating and shaping glass tubes. A typical shaping method is the vertical shaping method. In this method, a glass tube with a certain diameter and open ends is placed vertically, and the lower end, which becomes the opening, is heated to soften and shape the tube into the desired shape. The glass tube is then cut to the desired length, and the bottom of the glass container is formed to produce the desired glass container. The remaining glass tube is shortened by the length of each glass container produced, and by repeating this process, glass containers can be mass-produced.

[0005] However, when a glass container manufactured in this manner is used to store, for example, a liquid medicine, components of the glass leach out from the glass surface inside the glass container, contaminating the medicine. For example, alkali metals in the glass components can increase the pH value. In some cases, the glass components leach out from the glass surface and react with the liquid contents to form precipitates, thereby compromising the quality of the liquid contents.

[0006] Conventional methods for solving these problems, such as coating or sulfurizing the glass surface, have complicated the process and increased the manufacturing cost of glass containers, making it impossible to obtain glass containers with excellent chemical durability. Therefore, the present inventor previously filed a patent application for a method for manufacturing glass containers with excellent chemical durability (Patent Document 1). Patent Document 1 describes a method for manufacturing glass containers with excellent chemical durability, including a manufacturing process in which a glass tube is molded under heat to obtain a glass container, a cleaning process in which the inner surface of the glass container obtained in the manufacturing process is cleaned with a cleaning solution, and a strain relief process in which the glass container cleaned in the cleaning process is heated to a higher temperature and then cooled to remove strain. However, Patent Document 1 does not fully describe the cleaning process that takes into account the surface characteristics of the glass, nor the strain relief process, which is an important step for obtaining glass containers with excellent chemical durability. Patent Document 2 also describes a chemical vapor deposition method for silicon dioxide films, characterized by depositing a silicon dioxide film by plasma CVD using tetraisocyanate silane as a raw material gas. However, the method described in Patent Document 2 cannot provide a container that does not elute, or only elute in very small amounts, alkaline components and other elutable components from the surface due to reaction with liquid during storage.

[0007] Patent No. 6159304 Specification Patent No. 3305826 Specification

[0008] In the case of containers for pharmaceuticals or physicochemical use, it is desirable to provide containers that do not elute, or only elute very little, alkaline components or other elutable components from the surface of the manufactured containers, for example, during a heat sterilization process after filling the containers with a drug solution or due to reactions with the liquid during storage.

[0009] The present invention has been made in view of the problems inherent in the prior art, and its object is to provide a container that is extremely superior in chemical durability.

[0010] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that when the bottom end of a vertically standing glass tube is heated with, for example, a gas burner to soften it and then formed into a desired shape, the glass quality is altered by the heating, and volatile components of the glass (for example, Na) are released from the heated glass. ２ O.K. ２ O) is generated and rises due to the chimney effect in the space between the open lower and upper ends of the glass tube, whereupon these volatile components adhere to the inner surface of the glass tube to form alkaline components, which then elute from the glass surface after the glass container is manufactured.

[0011] Furthermore, the present inventors have found that when a glass container is obtained from a glass tube by the above-mentioned vertical molding method and the inner surface of the glass container is washed with a cleaning liquid before a strain relief operation for removing strain due to thermal history is performed, a glass container can be produced with extremely little elution of alkaline components from the inner glass surface.

[0012] However, when it comes to cleaning the inner surface of glass containers, there are a wide variety of cleaning methods available, and unless the cleaning process takes into consideration the surface characteristics of the glass, sufficient cleaning results cannot be achieved. There are more than 700 types of glass, and among these, borosilicate low alkali glass has an expansion coefficient of 3 × 10 －６ / K, is relatively hard with a Mohs hardness of about 7, and has high corrosion resistance, making it suitable for use in laboratory instruments, medical instruments, drug containers, etc. Borosilicate glass is preferred as the material for the glass container of the present invention.

[0013] Glass surfaces are inherently hydrophilic, highly chemically active, and have a strong ability to adsorb moisture and dirt due to intermolecular attractive forces such as hydrogen bonds. Glass is also a poor conductor of electricity, and has a strong ability to adsorb dirt. For example, if glass is left in the atmosphere, the glass surface reacts with the external atmosphere, causing deterioration accompanied by a change in the composition of the surface layer. Therefore, it is not easy to achieve the desired level of cleanliness by cleaning glass containers without adversely affecting the glass base material.

[0014] Typically, an acid or alkali can be used as a cleaning liquid for such glass containers. Table 1 below shows the weight loss (95°C, 24 hours (mg / cm)) of soda-lime glass, borosilicate glass, and quartz glass due to acid and alkali. ２ )) indicates.

[0015] As shown in Table 1, borosilicate glass shows the greatest weight loss in 5% sodium hydroxide. This is because silica, the main component, dissolves as sodium silicate. On the other hand, 5% hydrochloric acid mainly dissolves alkali and alkaline earth components contained in the glass, with very little silica component dissolving. Therefore, unlike sodium hydroxide, the amount of dissolution is small. The dissolution rate in acid is proportional to the square root of time and is significantly slower than the dissolution rate in alkali. Table 1 shows that acid corrosion is slower than alkali corrosion. It is also known that hydrochloric acid dissolves less in organic acids than in hydrochloric acid. Therefore, in the present invention, it is preferable to use an organic acid, which corrodes glass components relatively slowly, as the cleaning solution.

[0016] In addition, hydroxyl groups, such as silanol groups (SiOH), are generally present on glass surfaces, and it is believed that these hydroxyl groups act as adsorption sites for substances. Therefore, if the time between the cleaning process, in which the inner surface of a glass container is cleaned with a cleaning solution, and the subsequent strain relief process is long, the surface characteristics of the glass may change. In other words, it is preferable to keep the time between the cleaning process and the strain relief process to within 30 minutes. Furthermore, to improve the cleaning effect, it is preferable to set the spray pressure of the cleaning solution to 0.05 MPa or more.

[0017] Furthermore, when borosilicate glass is heated for a long time above the glass transition point, it transforms into a polar phase (Na ２ O, B ２ O ３ Glass that has separated into two phases (phase separation) can have a low chemical durability.

[0018] Therefore, the present inventors have conducted extensive research into conditions that make phase separation less likely to occur. As a result, they have found that in order to obtain glass containers with excellent chemical durability, in the manufacturing method of glass containers described in Patent Document 1, the heating temperature in the strain relief step, in which the glass container washed in the washing step is heated to an elevated temperature and then cooled to remove the strain, is extremely important. Based on this finding, the present inventors have found that by properly controlling the heating temperature in the strain relief step, it is possible to obtain chemically stable SiO without generating phase separation or free radicals. ２ It was found that a uniform coating containing a large amount of hydroxybenzoates was formed on the inner surface of the glass container.

[0019] Furthermore, some pharmaceutical and laboratory containers require that the amount of contaminants contained in the container's inner wall be kept below the detection limit (ppm or less). For example, the hydrolytic stability of pharmaceutical glass containers in the European Pharmacopoeia is evaluated based on their resistance to the release of water-soluble inorganic substances into water when the container's inner surface comes into contact with water. The European Pharmacopoeia classifies glass containers into three categories: Type I glass containers, which are suitable for most pharmaceutical preparations, regardless of whether they are parenterally administered; Type II glass containers, which are suitable for most acidic and neutral preparations, regardless of whether they are parenterally administered; and Type III glass containers, which are generally suitable for non-aqueous preparations, powders (excluding freeze-dried preparations), and oral preparations. The limit value for surface water resistance testing using flame atomic absorption spectrometry is set at 0.5 for the oxide concentration, expressed as sodium oxide (μg / mL), for Type I and II glass containers with a fill volume of more than 500 mL (milliliters).

[0020] To meet these stringent standards, it is necessary to apply appropriate treatments to the inner surface of the chamber to form a thin film with excellent water resistance. Thin film formation methods include "vacuum deposition," in which film-forming materials such as metals and oxides are evaporated in a vacuum chamber and then deposited on the opposing substrate surface to form a thin film; "ion plating," which uses a similar principle to vacuum deposition but involves passing evaporated particles through plasma to positively charge them and negatively charge the substrate on which the film is to be formed. The positively charged particles are attracted to the negatively charged substrate, forming a thin film with excellent adhesion; "sputtering," in which the metal to be deposited as a thin film is placed as a target in a vacuum chamber and a high voltage is applied to collide positively ionized rare gases (usually argon) or nitrogen with the negatively charged target to eject atoms from the target surface, forming a thin film on the substrate surface; and "chemical vapor deposition," in which a source gas containing the desired thin film components is supplied to a heated substrate in a quartz or other reaction tube, and a thin film is formed on the substrate by a gas-phase chemical reaction.

[0021] The above-mentioned "vacuum deposition," "ion plating," and "sputtering" methods belong to the category of physical vapor deposition (PVD), which is performed in a high vacuum. This is because if the film-forming precursor frequently collides with other particles, the precursor will not reach the substrate. In the high vacuum in which physical vapor deposition is performed, the precursor is transported to the substrate in a state almost similar to a molecular beam. Furthermore, since the precursor is often a highly reactive atom, when it arrives at the substrate surface, there is a nearly 100% probability that it will adhere. On the other hand, chemical vapor deposition (CVD) uses gaseous molecules as raw materials. Molecules containing the atoms to be deposited are supplied to a vessel containing the substrate, and some energy is applied to dissociate the molecules (chemical reaction). If the dissociation products containing the atoms to be deposited (precursors) are adhesive, thin film deposition is possible. The degree of vacuum required for CVD does not need to be as high as that required for PVD. In other words, CVD is performed in a high-pressure environment. This is because it is not necessary. Since higher pressure increases the density of the source material, increasing the pressure appropriately has the advantage of improving the film formation rate. In addition, collisions in the gas phase eliminate the directionality of the source material molecules, making it possible to supply the source material molecules to recesses, which is not possible with PVD.

[0022] Furthermore, while no chemical reactions occur during the transport of raw material particles in PVD, in CVD, numerous chemical reactions occur simultaneously in addition to the dissociation reaction of the raw material. Therefore, if the appropriate chemical reaction occurs, it is possible to incorporate functional groups possessed by the raw material molecules into the film, making it possible to obtain highly functional films that cannot be obtained by PVD. In this way, because CVD involves complex chemical reactions, it is possible to impart various functions to the film.

[0023] The raw materials used in CVD are stable molecules, so they must be dissociated in some way. Thermal CVD involves heating a substrate and using the resulting thermal energy to heat the raw material molecules. In contrast, in plasma CVD, electrons in the plasma containing the raw material molecules are the main drivers of decomposition. Therefore, since there is no need to heat the substrate to dissociate the raw material molecules, plasma CVD has the advantage of being able to form films on substrates that are sensitive to heat. Furthermore, in thermal CVD, where heat (vibrational excitation) is the driving force behind all reactions, the reactions and their products are all in thermal equilibrium, whereas plasma CVD, which utilizes electronic excitation, makes it possible to create materials that are out of thermal equilibrium.

[0024] Therefore, the inventors decided to adopt the plasma CVD method. However, the plasma CVD method also has a drawback: the ions required to maintain the plasma state damage the deposited film. Therefore, the inventors devised an improved plasma CVD method that overcomes this drawback and uses a different reaction system from the CVD method described in Patent Document 2, which uses tetraisocyanate silane as a raw material.

[0025] Specifically, the container surface treatment method of the present invention includes a cleaning step in which the inner surface of a glass container is washed with a cleaning solution consisting of water, an acid aqueous solution, a surfactant aqueous solution, or an acid aqueous solution containing a surfactant; a distortion-relieving step in which the glass container washed in the cleaning step is heated to an elevated temperature and then cooled to remove distortion; a subsequent step in which the glass container is placed in a vacuum chamber, and while supplying water vapor into the chamber to a predetermined pressure, discharge is irradiated with plasma to hydrophilize the surface of the glass container; a subsequent step in which tetraisocyanate silane or 1H,1H,2H,2H-heptadecafluorodecyltrimethoxysilane is supplied into the chamber without dissociating and reacted at a predetermined temperature for a predetermined time to form a thin film on the glass container; and a final step in which bonding between the glass container surface and the thin film is strengthened, by substituting surface functional groups with hydroxy groups in the case of tetraisocyanate silane. The surface structure of a container treated by this method, when tetraisocyanate silane is supplied, is composed of a silicon-based polymer containing urethane bonds, urea bonds, and biuret bonds. When 1H,1H,2H,2H-heptadecafluorodecyltrimethoxysilane is supplied, the surface structure of the container is composed of siloxane bonds.

[0026] The surface treatment method for a container of the present invention comprises placing a resin container in a vacuum chamber, irradiating the resin container with plasma by discharging while supplying water vapor into the chamber so as to reach a predetermined pressure, supplying tetraisocyanate silane or 1H,1H,2H,2H-heptadecafluorodecyltrimethoxysilane into the chamber after completion of the plasma irradiation and allowing a reaction to proceed at a predetermined temperature for a predetermined time to form a thin film on the resin container, and finally performing a treatment to strengthen the bond between the surface of the resin container and the thin film, and when tetraisocyanate silane is supplied, replacing surface functional groups with hydroxy groups.

[0027] According to the container surface treatment method of the present invention and the surface structure of a container treated by said method, the amount of alkaline components leaching from the inner surface of the container is extremely small, and deterioration of the contents, such as medicines, is suppressed, thereby ensuring that the specified quality is maintained.

[0028] FIG. 1(a) is a schematic diagram showing a state in which alkaline soluble components adhere to the inner surface of a glass container, FIG. 1(b) is a schematic diagram showing the glass container after the alkaline soluble components adhered to the inner surface have been removed, and FIG. 1(c) is a schematic diagram showing the state of a glass container having the inner surface shown in FIG. 1(b) after heating. FIG. 2 is a schematic diagram showing each substep of an example of a method for producing a borosilicate glass container of the present invention. FIG. 3 is a schematic diagram showing an example of a manufacturing apparatus suitable for use in the method for producing a borosilicate glass container of the present invention. FIG. 4 is a schematic diagram showing the process of cleaning a vial with a washer. FIG. 5 is a schematic cross-sectional view of one embodiment of a borosilicate glass container of the present invention. FIG. 6 is a schematic diagram showing the overall configuration of one embodiment of a plasma processing apparatus for performing plasma processing on a glass container. FIG. 7 is a cross-sectional view of a vacuum chamber of the plasma processing apparatus shown in FIG. 6. FIG. 8 shows the results of measuring the surface structure of a glass container using a Fourier transform infrared spectrophotometer, with the horizontal axis representing wavenumber ( / cm) and the vertical axis representing absorbance. FIG. 9 is a partial illustration of FIG. 8 , showing the results of measuring the surface structure of a glass container using a Fourier transform infrared spectrophotometer, with the horizontal axis representing wavenumber ( / cm) and the vertical axis representing absorbance. FIG. 10 is a partial illustration of FIG. 8 , showing the results of measuring the surface structure of a glass container using a Fourier transform infrared spectrophotometer, with the horizontal axis representing wavenumber ( / cm) and the vertical axis representing absorbance. FIG. 11 is a partial illustration of FIG. 8 , showing the results of measuring the surface structure of a glass container using a Fourier transform infrared spectrophotometer, with the horizontal axis representing wavenumber ( / cm) and the vertical axis representing absorbance. FIG. 12 is a diagram illustrating a chemical reaction on the surface of a glass container. FIG. 13 is another diagram illustrating a chemical reaction on the surface of a glass container.

[0029] The glass tube used as the material for the glass container of the present invention is not particularly limited, but is preferably made of borosilicate glass. The cross section of the glass tube is usually circular, but may be elliptical or other shapes. The diameter of the glass tube is not particularly limited, but is usually about 10 to 100 mm. The length of the glass tube is also not particularly limited, but is usually about 1 to 5 m. The glass tube may be colorless and transparent, or may be colored, for example, brown.

[0030] Methods for producing glass containers using such glass tubes have been well established, and the glass container of the present invention can be produced in accordance with these methods. For example, a glass tube having a certain diameter and open ends is placed vertically, and the lower end is inserted into a vertical molding machine, usually equipped with a heating means. The tube is heated, for example, with a gas burner at a temperature of about 1500 to 1800°C, to form the desired tube shape. The molded product and the remaining glass tube extending above are then separated under heat, forming a glass bottle and a bottom. The lower end of the separated glass tube is then reshaped to restore its cross section to its original circular shape. The temperature of the glass container after shaping is usually about 300 to 400°C.

[0031] By repeating this process, glass containers can be mass-produced. In this process, as described above, the glass is usually altered by heating, and volatile components of the glass (e.g., Na) are removed. ２ O.K. ２ O) rises in the space between the open upper and lower ends of the glass tube due to the chimney effect, adheres to the inner surface of the glass tube, and forms an alkaline elutable component.

[0032] In the present invention, after the above-mentioned glass container manufacturing process, the glass container undergoes a glass container washing process, which will be described in detail below, thereby removing or reducing alkaline soluble components adhering to the inner surface of the glass tube, and further, by subjecting the glass container after the washing process to a strain relief process within 30 minutes and subjecting the glass container to strain relief treatment controlled at an appropriate heating temperature, it is possible to provide a borosilicate glass container in which no phase separation occurs on the inner surface, no free radicals are present, no flakes or delamination are present, and in which silicon and oxygen present on the inner surface are bonded by siloxane bonds.

[0033] The glass container at about 300 to 400°C after molding is allowed to cool, for example, to ambient temperature, if necessary, and then washed with a cleaning solution, preferably at 150°C or below. It is believed that the higher the temperature of the glass container, the greater the effect of removing or reducing elutable components adhering to the inner surface of the glass container. However, contacting a high-temperature glass container with a cleaning solution may result in damage to the glass container. Furthermore, the lower limit temperature of the glass container during washing is preferably 30°C or higher, taking into account washing efficiency. Furthermore, a washing time of less than 10 seconds results in insufficient washing, while a washing time of more than 15 seconds results in reduced productivity, so a washing time of about 10 to 15 seconds is preferred.

[0034] Although there are no limitations on the temperature of the cleaning solution in the cleaning step, it is preferable to use a cleaning solution at about 30 to 100° C., and more preferably about 40 to 70° C. If the temperature is within this range, a glass container with extremely excellent chemical durability, which is the objective of the present invention, can be obtained.

[0035] As the cleaning liquid, water, an aqueous solution of an acid, an aqueous solution containing a surfactant, or an aqueous solution of an acid with the addition of a surfactant is preferably used, and an aqueous solution of an acid or an aqueous solution of an acid with the addition of a surfactant is more preferred in terms of high solubility of alkaline elutable components adhering to the inner surface of the glass container.

[0036] Acids used in the aqueous acid solution are broadly classified into organic acids and inorganic acids. Examples of organic acids include formic acid, acetic acid, oxalic acid, phthalic acid, and citric acid, while examples of inorganic acids include hydrochloric acid, sulfuric acid, and nitric acid. These acids may be used alone or in combination. For the reasons described above, organic acids are preferred, and citric acid and oxalic acid are preferred in terms of cleaning effect and ease of handling.

[0037] The higher the acid concentration, the higher the solubility of the alkaline component tends to be. However, from the viewpoint of ease of handling, including the treatment of waste liquid, the acid concentration is usually set to about 0.005 to 1.0 mol / L, preferably about 0.01 to 0.1 mol / L.

[0038] The surfactant used in the aqueous solution containing a surfactant or the aqueous acid solution containing a surfactant among the above cleaning solutions is not particularly limited, but a preferred surfactant is a nonionic surfactant. The concentration of the surfactant may be appropriately selected within a range that does not impair the object and effect of the present invention.

[0039] To clean the inner surface of a glass container with the above-mentioned cleaning solution, the glass container is usually inserted or suspended in a suitable jig, and the cleaning solution is sprayed upward from the mouth of the glass container toward the bottom, usually under pressure, from a nozzle. It is preferable to increase the spray pressure of the cleaning solution by, for example, discharging compressed air simultaneously with the cleaning solution from the nozzle spray outlet (also known as jet spray cleaning). Specifically, the spray pressure of the cleaning solution is preferably 0.05 MPa or higher. If the spray pressure is too high, the cleaning effect will saturate, so the upper limit of the spray pressure is about 0.5 MPa.

[0040] When a cleaning liquid other than water is used as the cleaning liquid, after cleaning with the cleaning liquid, the cleaning process is completed through a process of rinsing with clean water and a process of thoroughly draining the water by, for example, blowing air.

[0041] The cleaning of the inner surface of the glass container with the above cleaning solution may be performed by ultrasonic cleaning. In the case of ultrasonic cleaning, not only the inner surface but also the entire glass container is usually cleaned using the above cleaning solution, followed by rinsing. Whether or not to use ultrasonic cleaning is determined in consideration of the layout of the entire production line, including the vertical molding machine, cleaning machine, and strain relief furnace, which will be described later.

[0042] The strain relief process for glass containers in the present invention is carried out by feeding the glass containers cleaned in the cleaning process into a strain relief furnace controlled to a target maximum atmospheric temperature of 685 to 700°C, heating the glass container to a temperature of 685 to 710°C for 1 minute, and then cooling the glass container. The total time for the strain relief process, in which the glass container is heated to a temperature of about 30 to 80°C after cleaning in the strain relief furnace and then cooled to about 300°C, i.e., the time spent in the strain relief furnace (strain relief time), is 3 to 40 minutes. This strain relief process removes strain remaining in the glass container due to the thermal history during the forming process from the glass tube into a glass container, and at the same time, does not generate phase separation on the inner surface of the glass, does not contain free radicals, and produces chemically stable SiO ２ A uniform coating containing a large amount of silicon is formed on the inner surface, and a glass container is obtained which is free from flakes and delamination and in which silicon and oxygen present on the inner surface are bonded by siloxane bonds.

[0043] The process for obtaining the glass container of the present invention can be explained in simple terms as follows.

[0044] (1) Adhesion of alkaline eluting components to the inner surface of the glass tube. As described above, when the glass tube is heated with a gas burner at a temperature of about 1500 to 1800°C and molded into the desired shape of the tube, the glass quality is altered by heating, and volatile components of the glass (e.g., Na) are released. ２ O.K. ２ The alkaline elutable component 3 adheres to the inner surface 2 of the glass tube 1.

[0045] (2) Removal of alkaline elutable components by washing Although alkaline elutable components can be removed by washing, the washing results in the inner surface 5 of the glass container 4 becoming microscopically uneven, as shown in FIG. 1(b).

[0046] (3) Removal of residual strain due to thermal history during molding: Residual strain can be removed by heating the glass container after removing the alkaline eluting components. In addition, atomic diffusion improves the flatness of the inner surface 5 of the glass container 4, as shown in Figure 1(c).

[0047] (4) Formation of the inner surface of glass containers Borosilicate glass can undergo phase separation when heated to temperatures above its glass transition point for a long period of time. Furthermore, if the heating temperature is too high, deformation and wrinkles will occur in the glass container. Therefore, the selection of heating conditions is extremely important.

[0048] Therefore, the glass container of the present invention can be manufactured by controlling a strain-removing furnace that is controlled to a target maximum atmospheric temperature of 685 to 700°C so that the actual temperature of the glass container is kept at 685 to 710°C for one minute. If the time at 685 to 710°C is one minute, no phase separation occurs on the inner surface, no free radicals are present, silicon and oxygen present on the inner surface are bonded by siloxane bonds, the glass surface does not deform or wrinkle, residual strain due to thermal history is removed, and a glass container with substantially smooth inner and outer surfaces can be manufactured.

[0049] If the temperature of the glass container itself exceeds 700°C for a long period of time (10 minutes or more), the glass surface may be deformed or wrinkled. On the other hand, if the maximum atmospheric temperature of the distortion removal furnace is controlled to be less than 650°C, the temperature of the glass container itself is likely to fall below 600°C, which may result in insufficient vitrification.

[0050] (5) Plasma Treatment Organic molecules exhibit a unique adsorption phenomenon to solid surfaces, and during the adsorption process, they may form a densely packed, uniformly oriented molecular film. When the adsorbed molecular layer is a single layer, i.e., a monolayer, this is called a self-assembled monolayer (hereinafter sometimes referred to as a SAM film). When the adsorbed molecular layer is two or more layers, it is called a self-assembled multilayer film. Therefore, the glass container manufactured as described above is placed in the vacuum chamber of a plasma processing device, and a SAM film or a self-assembled multilayer film is formed on the surface of the glass container. That is, in a state where an evaporation source that imparts hydrophilic groups is supplied into a vacuum chamber of a plasma processing apparatus having a predetermined vacuum level, a surface hydrophilization mode is executed in which the film formation surface of the glass container is modified to hydrophilize the film formation surface using a plasma atmosphere formed by a plasma generating unit; in a state where an evaporation source that promotes hydrolysis or nucleophilic reaction of a precursor material of a SAM film or a self-assembled multilayer film is supplied into a vacuum chamber of a predetermined vacuum level to the glass container whose film formation surface has been hydrophilized, an evaporation source of a precursor material of a SAM film or a self-assembled multilayer film is supplied to the hydrophilized film formation surface; and finally, in a vacuum chamber of a predetermined vacuum level, a final processing mode is executed in which the bond between the film formation surface of the glass container and the SAM film or the self-assembled multilayer film is strengthened. Note that a similar process can also be performed on a resin container instead of a glass container in the plasma processing apparatus to form a SAM film or a self-assembled multilayer film on the resin container. Examples of such resins include propylene (PP), polyethylene (PE), cycloolefin (COP, COC), polyethylene terephthalate (PET), and polyvinyl chloride (PVC).

[0051] The present invention provides a container with an extremely small amount of elution of alkaline components and the like.

[0052] Although the present invention will be described below by way of example, it goes without saying that various changes and modifications can be made without departing from the technical scope of the present invention.

[0053] A 2 mL vial was obtained using a borosilicate glass tube having an outer diameter of 16 mm, a length of 1.6 m, and the composition (wt %) shown in Table 2 below, by the following method. First, as shown in Figure 2 (1), the glass tube 11 was inserted into a vertical tube bottle molding machine 12 with its end facing up, and the lower end was heated with a gas burner to soften the glass, which was then molded into the shape of the opening of the bottle. The process will be explained in more detail below with reference to Figure 2.

[0054]

[0055] (1) The bottom end of the glass tube 11 was heated with a fishtail burner 13 at 1200 to 2000°C. (2) The shoulder was formed using a roller 14 and plunger 15. (3) It was heated with a point burner 16 at 1200 to 2000°C. (4) The neck was formed using the roller 14 and plunger 15. (5) The bottle height was determined using a total height plate 17. (6) It was cut using a cut burner 18 at a temperature of 1200 to 2000°C. (7) The bottom was homogenized using the point burner 16. (8) Air 19 was blown in, and the bottom of the vial 20 was formed using the point burner 16 at 1200 to 2000°C.

[0056] The vials 20 thus obtained were inserted into a jig placed on a net conveyor 21 (FIG. 3), and transported to a washer 22, where they were allowed to cool at ambient temperature (cooling step (9) in FIG. 2). The inner surfaces of the vials, which were about 30°C, were spray-cleaned with 10 mL of a cleaning solution (citric acid) at 25°C for 10 seconds using a syringe (citric acid spray pressure: 0.2 MPa) (cleaning step (10) in FIG. 2). They were then spray-cleaned with purified water for 10 seconds (0.2 MPa), and the water was then thoroughly drained by blowing in air 19 (draining step (11) in FIG. 2). Although details are omitted in FIG. 3, the vials 20 can be transported to the washer 22 and strain-removing furnace 24 by the net conveyor 21.

[0057] Figure 4 is a schematic diagram showing how vials 20 are washed by washer 22. In Figure 4, reference numeral 31 denotes a manifold, 32 denotes a nozzle, 33 denotes a needle valve, 34 denotes a flow meter, 35 denotes a pressure gauge, 36 denotes a pump, and 37 denotes a storage tank for the washing liquid. The spray pressure of the washing liquid can be adjusted by adjusting the opening of needle valve 33.

[0058] After washing with citric acid and purified water and draining, the vials 20 were transported to a 5-m-long, 5-meter-long strain-removing furnace 24 equipped with a burner heater 23 within 30 minutes (see strain-removing step (12) in Figure 2 ). The strain-removing furnace was controlled to a target maximum ambient temperature of 670°C for 25 minutes (the ambient temperature was 670°C or higher for 108 seconds, the actual temperature of the glass container was 670-700°C, and the actual temperature of the glass container was 690-700°C for 1 minute). A borosilicate glass container was obtained, and the glass container was then allowed to cool to room temperature. Figure 5 shows a schematic cross-section of a borosilicate glass container 40 obtained in this manner. Because the strain-removing furnace 24 has open inlet and outlet sides, even if the ambient temperature inside the strain-removing furnace, as detected by a thermocouple installed inside the strain-removing furnace, is, for example, 670-700°C, the temperature at the inlet and outlet sides will be lower than this temperature. The atmospheric temperature in the strain-removing furnace was measured by thermocouples installed at three locations, and the burner heater 23 was controlled to turn on and off so that the temperature measured by one of the thermocouples became the target temperature. Furthermore, the actual temperature of the glass container was measured by a thermocouple fused to the glass container.

[0059] FIG. 6 is a schematic diagram showing the overall configuration of one embodiment of a plasma processing apparatus for forming a SAM film or a self-assembled multilayer film by subjecting the glass container thus obtained to plasma processing, and FIG. 7 is a cross-sectional view of the vacuum chamber of the plasma processing apparatus shown in FIG. 6.

[0060] As shown in FIG. 6 , a plasma processing apparatus 51 includes a vacuum chamber 52 that accommodates a glass container V on which a SAM film or a self-assembled multilayer film is to be formed, a lower electrode 53 that also serves as a stage for placing the glass container V in the vacuum chamber 52, and an upper electrode 54 that faces the lower electrode 53. A plasma generation power supply 57 is connected to the lower electrode 53. While FIG. 6 shows a structure in which the lower electrode 53 supports the glass container V, a structure in which the upper electrode 54 supports the glass container V, or a structure in which both the lower electrode 53 and the upper electrode 54 support the glass container V, may also be used. The plasma generation power supply 57 may be a low-frequency power supply or a high-frequency power supply. Furthermore, a pressure gauge 55 that monitors the pressure within the vacuum chamber 52, a ground 56, and a vacuum pump 59 are connected to the vacuum chamber 52. The system also has a structure in which a gas inlet 60 used for plasma treatment, a bubbler 65 for reactant substances necessary for plasma treatment and for forming a SAM film or a self-assembled multilayer film, and a raw material chamber 68 for the SAM film or the self-assembled multilayer film are connected by piping and introduced into the vacuum chamber 52.

[0061] Furthermore, as shown in FIG. 7 , the vacuum chamber 52 in this embodiment has an upper chamber 77 and a lower chamber 78, with an O-ring 80 in the lower chamber 78. In this embodiment, the upper chamber 77 and the lower chamber 78 are made of electrically grounded electrical conductors, and the entire inner wall surface of the vacuum chamber 52 serves as a ground potential surface. The electrical conductors constituting the upper chamber 77 and the lower chamber 78 are metallic materials such as transition metals such as copper, nickel, and titanium, alloys thereof, and refractory metals such as stainless steel, molybdenum, and tungsten. In this embodiment, a gas inlet 71 is provided at the top of the upper chamber 77, and piping is connected to the gas inlet 71 from a gas inlet 60 used for plasma processing, a bubbler 65 for reactant materials necessary for plasma processing and the film formation process of a SAM film or a self-assembled multilayer film, and a raw material chamber 68 for the SAM film or the self-assembled multilayer film.

[0062] In this embodiment, the lower electrode 53 is composed of a current introduction terminal 72 and an electrode stage 73, and insulating members 76 are disposed around the current introduction terminal 72 and below the electrode stage 73. The current introduction terminal 72 is also connected to a plasma generation power supply 57. The upper electrode 54, facing the lower electrode 53, also functions as a gas shower plate 74. In this embodiment, the lower chamber 78 is provided with a ground ring 75 surrounding the electrode stage 73. Preferably, the height difference between the electrode stage 73 and the ground ring 75 is approximately 0 mm, but the ground ring 75 may be slightly higher than the electrode stage 73. The ground ring 75 is spaced from the electrode stage 73 by a distance of 1 mm to 5 mm. This spacing makes it possible to control the gas flow and maximize the uniform plasma region. If the spacing between the ground ring 75 and the electrode stage 73 is less than 1 mm, the gap will be too narrow to adequately draw gas when using a vacuum pump. Furthermore, abnormal discharge will occur, preventing the desired plasma from being generated. Furthermore, if the distance between the earth ring 75 and the electrode stage 73 is greater than 5 mm, abnormal discharge occurs between the electrode stage 73 and the earth ring 75, making it impossible to generate the desired uniform plasma.

[0063] Furthermore, the lower chamber 78 has a vacuum exhaust port 79 connected to a vacuum pump 59 between the current introducing terminal 72 and the earth ring 75, and the degree of vacuum inside the vacuum chamber 52 can be adjusted with an exhaust flow rate adjusting valve 58. Therefore, by using the apparatus of this embodiment, it is possible to effectively perform hydrophilization treatment by plasma treatment in the pretreatment step of forming a SAM film or a self-assembled multilayer film.

[0064] In this embodiment, three gas introduction pipes, consisting of a system from a gas inlet 60 for introducing gas used in plasma treatment, a system from a bubbler 65 for reactant materials necessary for plasma treatment and the film formation process of a SAM film or a self-assembled multilayer film, and a system from a raw material chamber 68 for the SAM film or the self-assembled multilayer film, are connected to the vacuum chamber 52. The gas introduction pipes are surrounded by a heat insulating material or a heater (not shown) to prevent the gas from liquefying.

[0065] In this embodiment, the gas used in the plasma treatment introduced from the gas inlet 60 is supplied from a gas cylinder (not shown) and introduced into the vacuum chamber 52 via a flow rate adjusting valve / mass flow controller 61. As the gas used in the plasma treatment, a gas that imparts hydroxyl groups (OH groups) to the surface of the glass container V, or a pre-treatment gas for the step of imparting OH groups is selected. For example, water vapor (H ２ O), oxygen (O ２ ) and argon (Ar). There are no particular limitations on the gas as long as it is a gas that can impart OH groups to the surface or can be used for pretreatment in the step of imparting OH groups.

[0066] When the gas used for plasma treatment is supplied to the vacuum chamber 52, the degree of vacuum in the vacuum chamber 52 is controlled by the exhaust flow control valve 58 and the vacuum pump 59, and by discharging between the lower electrode 53 and the upper electrode 54, the gas functions as a plasma generating gas, and plasma hydrophilization treatment is performed on the glass container V.

[0067] In this embodiment, bubbler 65, into which vapor source 67, a reactant substance necessary for plasma processing and for forming a SAM film or a self-assembled multilayer film, is injected, is equipped with a mantle heater 66, and by heating, vapor of vapor source 67, a reactant substance necessary for plasma processing and for forming a SAM film or a self-assembled multilayer film, is generated and supplied to vacuum chamber 52. Bubbler 65 is connected to a pipe through which carrier gas is supplied from carrier gas inlet 62 for carrying the vapor of vapor source 67 via flow rate adjustment valve / mass flow controller 63, and the pipe is configured to have a bypass valve 64 through which carrier gas passes that can be mixed with the vapor from bubbler 65 without passing through bubbler 65. If carrier gas is not required, it is not necessary to flow carrier gas.

[0068] As the vapor source 67, which is a reactant material necessary for plasma treatment and for forming a SAM film or a self-assembled multilayer film, a vapor source that provides OH groups to the surface of the glass container V or a vapor source that promotes hydrolysis or nucleophilic reaction of the precursor of the SAM film or the self-assembled multilayer film is selected. For example, water (H ２ O) is exemplified.

[0069] When the vapor of the vapor source 67, which is a reactant material necessary for plasma processing and for forming a SAM film or a self-assembled multilayer film, is supplied to the vacuum chamber 52, the H ２ The O gas (water vapor) functions as a plasma generating gas to provide OH groups to the surface of the glass container V. In the subsequent SAM film or self-assembled multilayer film formation process, the residual component (water vapor) of the plasma generated during the discharge promotes a hydrolysis or nucleophilic reaction with the SAM film or self-assembled multilayer film precursor material. By controlling the degree of vacuum in the vacuum chamber 52 with an exhaust flow rate control valve 58 and a vacuum pump 59, the subsequent hydrolysis or nucleophilic reaction of the SAM film or self-assembled multilayer film precursor can occur during or after the discharge has stopped, as long as the SAM film or self-assembled multilayer film precursor is not decomposed or dissociated.

[0070] In this embodiment, the SAM film or self-assembled multilayer film source chamber 68, into which a vapor source 70 of the SAM film or self-assembled multilayer film precursor material is injected, is equipped with a mantle heater 69, and vapor is generated from the SAM film or self-assembled multilayer film source chamber 68 by heating with the mantle heater 69, and supplied to the vacuum chamber 52. As the SAM film or self-assembled multilayer film precursor material vapor source 70, an evaporation source that undergoes dehydration condensation between OH groups formed by hydrolysis of the SAM film or self-assembled multilayer film precursor material and OH groups formed on the surface of the glass container V, or an evaporation source that undergoes dehydration condensation between the material molecules of the evaporation source of the SAM film or self-assembled multilayer film precursor material themselves and OH groups formed on the surface of the glass container V, is selected. For example, chlorosilanes such as 1H,1H,2H,2H-perfluorodecyldimethylchlorosilane, tetrahydrooctylmethyldichlorosilane (FOMDS), dichlorodimethylsilane (DDMS), 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS), octadecyltrichlorosilane (OTS), and tetrahydrooctyltrichlorosilane (FOTS); dimethyldimethoxysilane, dimethyldiethoxysilane, isobutylmethyldimethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, dodecyltriethoxysilane, 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, 1H,1H,2H,2H-tridecafluorooctyl Examples of the material include alkoxysilane-based materials such as octadecyltrimethoxysilane, n-octadecyltrimethoxysilane, and tetraethoxysilane (TEOS); phosphonic acid-based materials such as octadecylphosphonic acid and 1H,1H,2H,2H-perfluorooctylphosphonic acid; isocyanate-based materials such as tetraisocyanatosilane; alkoxysilane-based and isocyanate-based materials such as triethoxy(3-isocyanatopropyl)silane; and disilazanes such as hexamethyldisilazane (HMDS). The material is not limited to chlorosilane-based materials, alkoxysilane-based materials, isocyanate-based materials, phosphonic acid-based materials, and disilazanes that can form a SAM film or a self-assembled multilayer film.

[0071] When the vapor source 70 of the SAM film or self-assembled multilayer film precursor material is supplied to the vacuum chamber 52, it is preferable not to discharge between the lower electrode 53 and the upper electrode 54. In the SAM film or self-assembled multilayer film forming process, if the vapor source 70 of the SAM film or self-assembled multilayer film precursor material is tetraisocyanate silane, residual components of the plasma during discharge and H ２ While O undergoes a nucleophilic reaction with the self-assembled multilayer film precursor material, the unreacted isocyanate groups among the four isocyanate groups react with OH groups provided on the surface of the glass container or the surface of the resin container to form urethane bonds, thereby forming the first layer of the self-assembled multilayer film. When the vapor source 70 of the SAM film or the self-assembled multilayer film precursor material is 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, residual components of the plasma during discharge and H ２ After O undergoes a hydrolysis reaction with the SAM film precursor material, the OH groups attached to the surface of the glass container or the surface of the resin container and the OH groups of the SAM film precursor material self-organize through hydrogen bonding, and then a dehydration condensation reaction proceeds, forming a SAM film.

[0072] As described above, the plasma processing apparatus of this embodiment includes a plasma generating unit that forms a plasma atmosphere in a vacuum chamber and has three processing modes: (1) a surface hydrophilization mode in which an evaporation source that imparts hydrophilic groups is supplied into the vacuum chamber, and the film formation surface of a glass container or a resin container is modified by the plasma atmosphere formed by the plasma generating unit to hydrophilize the film formation surface; (2) a self-assembly mode in which an evaporation source that promotes hydrolysis or nucleophilic reaction of the precursor material for a SAM film or a self-assembled multilayer film is supplied into a vacuum chamber with a predetermined vacuum level to the glass container or resin container whose film formation surface has been hydrophilized, and a SAM film or a self-assembled multilayer film is formed on the hydrophilized film formation surface; and (3) a final processing mode consisting of a heat treatment in a vacuum chamber with a predetermined vacuum level to strengthen the bond between the film formation surface and the SAM film or the self-assembled multilayer film, and a silanolization treatment of the outermost surface when the precursor material for the self-assembled multilayer film is tetraisocyanate silane.

[0073] In this embodiment, the surface hydrophilization mode, the self-assembly mode, and the final processing mode are preferably performed in a common vacuum chamber. This allows the transition from the surface hydrophilization mode to the self-assembly mode, and from the self-assembly mode to the final processing mode, to be performed without opening the vacuum chamber to the atmosphere. Note that, when the surface hydrophilization mode, the self-assembly mode, and the final processing mode are performed in separate vacuum chambers, it is preferable that the vacuum chamber be a load-lock type that can transport containers while maintaining a vacuum state.

[0074] In this embodiment, the evaporation source that provides hydroxyl groups to the surface of the container and the evaporation source that promotes hydrolysis of the precursor material of the self-assembled monolayer are both preferably water vapor. Note that the water vapor in the self-assembly mode may be water vapor remaining in the surface hydrophilization mode.

[0075] According to this embodiment, by performing vacuum plasma treatment on the substrate surface immediately before forming a SAM film or a self-assembled multilayer film on the container, it is possible to impart hydrophilic groups such as hydroxyl groups at a high density, and it is possible to form a high-density SAM film on the surface of the container without opening the vacuum chamber to the atmosphere and before the hydrophilicity of the hydrophilic groups imparted to the container changes over time.

[0076] Furthermore, the method for forming a SAM film or a self-assembled multilayer film in this embodiment includes the steps of: (A) placing a glass container in a vacuum chamber; (B) supplying an evaporation source that imparts hydrophilic groups to the surface of the glass container into the vacuum chamber and generating plasma from the evaporation source by turning the vacuum chamber into a plasma, thereby hydrophilizing the surface of the glass container; (C) after step (B), supplying an evaporation source of a precursor material for the SAM film or self-assembled multilayer film into the vacuum chamber while the evaporation source that promotes hydrolysis or a nucleophilic reaction of the precursor material for the SAM film or self-assembled multilayer film has been supplied; and (D) strengthening the bond between the glass container surface and the SAM film or self-assembled multilayer film, and silanolizing the outermost surface when the precursor material for the self-assembled multilayer film is a tetrafunctional alkoxysilane such as tetraisocyanate silane or tetraethyl orthosilicate; and at least steps (B) and (C) are performed without opening the vacuum chamber to the atmosphere. Step (D) may be performed in a vacuum chamber without exposing it to the atmosphere, or may be performed after exposing it to the atmosphere.

[0077] Then, the glass container V made of borosilicate glass obtained as described in paragraphs 0053 to 0058 was placed in the plasma processing apparatus shown in Figure 6, and the surface of the glass container V was subjected to the treatment described below to form a self-assembled multilayer film.

[0078] The atmospheric pressure in vacuum chamber 52 was reduced to 5 to 10 Pa. Thereafter, bubbler 65, into which water had been injected as vapor source 67, a reactant substance necessary for plasma treatment and SAM film formation, was heated to 70°C by mantle heater 66, and water vapor was introduced into vacuum chamber 52, maintaining the atmospheric pressure in vacuum chamber 52 at 100 Pa. A 13.56 MHz high-frequency power source was used as plasma generation power source 57, and water vapor plasma irradiation was carried out for 3 minutes at a power of 200 W.

[0079] A source chamber 68 for the SAM film or self-assembled multilayer film, into which 5 cc of tetraisocyanate silane was injected as a vapor source 70 of a precursor material for the SAM film or self-assembled multilayer film, was heated to 50° C. by a mantle heater 69. After plasma irradiation was completed, the valve of the bubbler 65 was closed, and then, without opening the vacuum chamber 52 to the atmosphere, the valve of the source chamber 68 for the SAM film or self-assembled multilayer film was opened to introduce tetraisocyanate silane into the vacuum chamber 52. The glass container V was exposed to the vapor of tetraisocyanate silane for 20 minutes, thereby forming a self-assembled multilayer film on the glass container V.

[0080] Furthermore, the glass container on which the self-assembled multilayer film was formed was heated to 100-120°C to strengthen the bond between the surface of the glass container and the interior of the self-assembled multilayer film. After that, water vapor plasma was again irradiated to form silanol groups on the outermost surface, resulting in a hydrophilic surface.

[0081] Next, the same treatment as above was performed on glass container V made of borosilicate glass obtained as described in paragraphs 0053 to 0058 and paragraphs 0078 to 0079, except that 1H,1H,2H,2H-perfluorodecyltrimethoxysilane was used instead of tetraisocyanatesilane as vapor source 70 of the SAM film or self-assembled multilayer film precursor material. Thereafter, glass container V on which the 1H,1H,2H,2H-perfluorodecyltrimethoxysilane SAM film had been formed was heated to 100 to 120°C, thereby strengthening the bond between the glass container surface and the SAM film.

[0082] Then, using a Fourier transform infrared spectrophotometer, the molecules formed on the surface of glass container V, which had been treated using the above-mentioned tetraisocyanate silane as a raw material for the self-assembled multilayer film, were identified. Because infrared light is absorbed as the energy of vibrations and rotational motions of molecular bonds, information on the molecular structure and functional groups can be obtained from the spectrum. Figure 8 shows the results of measuring the surface structure of the glass container using a Fourier transform infrared spectrophotometer, with the horizontal axis representing wavenumber ( / cm) and the vertical axis representing absorbance. Figures 9, 10, and 11 are partial excerpts from Figure 8.

[0083] By subjecting the surface of glass container V to plasma treatment according to the method of the present invention, it can be seen that urethane bonds (chemical formula 1) are formed on the surface of the glass container, as shown in FIG. 12, and urea bonds (chemical formula 2) and biuret bonds (chemical formula 3) are formed on the surface of the glass container, as shown in FIG. 13.

[0084]

[0085]

[0086]

[0087] Furthermore, a glass container made of borosilicate glass of Comparative Example 1 was obtained through the same steps as those described in paragraphs 0053 to 0058, except that no plasma surface treatment was performed. A glass container made of borosilicate glass of Comparative Example 2 was obtained through the same steps as those described in paragraphs 0053 to 0058, except that no plasma surface treatment was performed and no washing with citric acid and purified water was performed.

[0088] Thereafter, for a borosilicate glass container (Example 1) surface-treated with tetraisocyanate silane using a plasma treatment device, a borosilicate glass container (Example 2) surface-treated with perfluorocarbon using a plasma treatment device, a borosilicate glass container of Comparative Example 1, and a borosilicate glass container of Comparative Example 2, 0.7 mL of purified water 40a was poured into each glass container 40 as shown in FIG. 5, and then autoclaved at 121°C for 2 or 4 hours. 41 denotes a rubber stopper. Then, for the purified water in these glass containers, the amount of eluted Na (ppm) was measured using an atomic absorption spectrophotometer, and the amount of eluted B (ppm), amount of eluted Al (ppm), amount of eluted Si (ppm), amount of eluted Ca (ppm), and amount of eluted Ba (ppm) were measured using an inductively coupled plasma optical emission spectrometer. As a result, the measurement results shown in Tables 3 to 8 below were obtained. Injecting purified water into a glass container serves as an accelerated test to estimate how long it will take for the inner surface of a glass container to deteriorate when a pharmaceutical product (e.g., a liquid, a freeze-dried preparation, or a powder) is stored in the glass container, and one hour after the injection of purified water corresponds to 1.6 years.

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095] As shown in Tables 3 to 8, the borosilicate glass containers of Examples 1 and 2 had extremely low elution amounts of all six elements, demonstrating excellent chemical durability. On the other hand, the borosilicate glass container of Comparative Example 1 had similar elution amounts of elements other than Na as the borosilicate glass containers of Examples 1 and 2, but had a higher elution amount of Na than the borosilicate glass containers of Examples 1 and 2. Furthermore, the borosilicate glass container of Comparative Example 2, which was not subjected to a surface treatment, had a high elution amount of all six elements.

[0096] Furthermore, the so-called contact angle, which is the angle between the liquid surface and the solid surface where the free surface of the stationary liquid comes into contact with the solid wall, was measured for the glass container of Example 2, the glass container of Comparative Example 2, the polypropylene container (PP container), and the cycloolefin container (COP container). This contact angle is determined by the magnitude relationship between the cohesive force between liquid molecules and the adhesive force between the liquid and the solid wall, and the contact angle θ is defined as the surface tension of the liquid, and σ is defined as the surface tension of the liquid. Ｌ Let the surface tension of the σ solid be σ Ｓ Let the interfacial tension between the solid and the liquid be σ ＳＬ Then, it can be expressed by the following formula: cos θ = (σ Ｓ -σ ＳＬ ) / σ Ｌ 　 The PP containers and COP containers were obtained by injection molding so as to have the same external shapes as the glass containers of Examples 1 and 2 and Comparative Examples 1 and 2.

[0097] The contact angles (degrees) were then measured for the four types of containers using the sessile drop method, which involves "measuring the coordinates of the droplet contour curve, assuming that the droplet contour shape is represented by a Young-Laplace theoretical curve, calculating the parameters of the curve from the coordinates of the contour shape, determining a specific function that represents the curve, differentiating the function with respect to the endpoint coordinates to find the tangent, and determining the contact angle from the gradient of the tangent." The liquids used were water, 85% ethanol, acetone, and salad oil. The contact angle (degree) measurement results are shown in Tables 9 to 12 below.

[0098]

[0099]

[0100]

[0101]

[0102] As shown in Table 9, the contact angle of the glass container of Example 2 exceeds 90° when the liquid is water, indicating that it has water repellency similar to that of the PP and COP containers. However, the contact angle of the glass container of Comparative Example 2 is less than 90° when the liquid is water, indicating that it is hydrophilic.

[0103] When the liquid was 85% ethanol, acetone, or salad oil, as shown in Tables 10 to 12, the glass container of Comparative Example 2 was impossible to measure, and the PP container and COP container were also almost impossible to measure, but the glass container of Example 2 had a certain contact angle and cannot be said to be lipophilic.

[0104] According to the present invention, a container suitable for use in pharmaceuticals and physicochemical applications can be provided.

[0105] 51 Plasma processing apparatus 52 Vacuum chamber 53 Lower electrode 54 Upper electrode 55 Pressure gauge 56 Earth 57 Plasma generation power supply 58 Exhaust flow rate adjustment valve 59 Vacuum pump 60 Gas inlet 62 Carrier gas inlet 65 Bubbler for reactant material 66, 69 Mantle heater 67 Vapor source of reactant material 68 Source chamber for SAM film or self-assembled multilayer film 70 Vapor source of SAM film or self-assembled multilayer film precursor material 71 Gas inlet 72 Current input terminal 73 Electrode stage 74 Gas shower plate 75 Earth ring 76 Insulating member 77 Upper chamber 78 Lower chamber 79 Vacuum exhaust port 80 O-ring

Claims

1. A method for surface treatment of a container, comprising: a cleaning step in which the inner surface of a glass container is cleaned with a cleaning solution consisting of water, an acid aqueous solution, a surfactant aqueous solution, or an acid aqueous solution containing a surfactant; a distortion-removing step in which the glass container cleaned in the cleaning step is heated to a predetermined temperature and then cooled to remove distortion; subsequently, placing the glass container in a plasma treatment device; supplying an evaporation source that imparts hydrophilic groups to a vacuum chamber of the plasma treatment device, and modifying the film-forming surface of the glass container to make it hydrophilic using a plasma atmosphere formed by a plasma generating unit; supplying an evaporation source that promotes the hydrolysis or nucleophilic reaction of a precursor material for a SAM film or self-assembled multilayer film to the glass container with the hydrophilic film-forming surface, and finally strengthening the bond between the film-forming surface and the SAM film or self-assembled multilayer film in the vacuum chamber of the predetermined vacuum level.

2. A method for treating the surface of a container, characterized by placing a resin container in a plasma processing device, supplying an evaporation source that imparts hydrophilic groups into a vacuum chamber of the plasma processing device, modifying the film-forming surface of the resin container using a plasma atmosphere formed by a plasma generating unit to make the film-forming surface hydrophilic, supplying an evaporation source that promotes the hydrolysis or nucleophilic reaction of a precursor material for a SAM film or self-assembled multilayer film into the vacuum chamber of the predetermined vacuum degree, and then supplying an evaporation source of a precursor material for a SAM film or self-assembled multilayer film to the resin container with the hydrophilic film-forming surface to form a SAM film or self-assembled multilayer film on the hydrophilic film-forming surface, and finally strengthening the bond between the film-forming surface and the SAM film or self-assembled multilayer film in the vacuum chamber of the predetermined vacuum degree.

3. A surface structure of a container made of a silicon-based polymer containing urethane bonds and biuret bonds, obtained by treating the surface with the method of claim 1.

4. A container treated by the method of claim 1 or 2, in which the amount of Na, B, Al, Si, Ca or Ba eluted from the container surface is less than 1 ppm.

5. A container treated by the method of claim 2, wherein the contact angle is greater than 90°.

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