Tube glass for pharmaceutical container and method for producing pharmaceutical container

Abstract

A tube glass 1 for a pharmaceutical container has: a cylindrical side-wall part 2; and a bottom part 3 for sealing one end side of the side-wall part 2. The bottom part 3 has: a grounding part 4 connected to the one end of the side-wall part 2; and a raised bottom part 5 provided inside the grounding part 4. The average thickness t1 [mm] of the side-wall part 2 and the average thickness t2 [mm] of the grounding part 4 satisfy the relationship t2 / t1>1.025.

Description

Glass tube for pharmaceutical containers and method of manufacturing pharmaceutical containers

[0001] The present invention relates to a glass tube for pharmaceutical containers and a method for manufacturing pharmaceutical containers.

[0002] In the pharmaceutical container manufacturing process, a long pharmaceutical container glass tube is first set in a vertical position (e.g., with the tube axis oriented vertically) in a pharmaceutical container manufacturing device. The vertically oriented pharmaceutical container glass tube is then heated with a burner to be cut or thermally processed into a predetermined shape. In this manner, multiple pharmaceutical containers are successively manufactured from a single pharmaceutical container glass tube (see, for example, Patent Documents 1 and 2).

[0003] JP-A-54-143418 JP-A-54-143419

[0004] In the pharmaceutical container manufacturing process, in order to set the pharmaceutical container glass tube in a vertical position in the pharmaceutical container manufacturing device, the pharmaceutical container glass tube may be dropped with its bottom facing down onto a flat plate.

[0005] However, if the shape of the bottom of a glass tube for pharmaceutical containers is inappropriate, the glass tube for pharmaceutical containers may be broken by the impact of being dropped.

[0006] An object of the present invention is to prevent glass tubes for pharmaceutical containers from being broken due to impact from being dropped.

[0007] (1) The present invention, which has been invented to solve the above-mentioned problems, is a glass tube for pharmaceutical containers, which comprises a cylindrical side wall portion and a bottom portion sealing one end of the side wall portion, wherein the bottom portion comprises a ground portion connected to one end of the side wall portion and a raised bottom portion provided inside the ground portion, and wherein the average thickness t1 [mm] of the side wall portion and the average thickness t2 [mm] of the ground portion satisfy the relationship t2 / t1>1.025.

[0008] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing downward onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop is small, and as a result, the glass tube for pharmaceutical containers is less likely to break due to the impact of the drop.

[0009] (2) In the configuration of (1) above, it is preferable that the average thickness t2 [mm] of the ground contact portion and the average thickness t3 [mm] of the center of the raised bottom portion satisfy the relationship −0.8<(t2−t3)<0.5.

[0010] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing down onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop will be small, making the glass tube for pharmaceutical containers less likely to break when dropped.

[0011] (3) In the configuration of (1) or (2) above, it is preferable that the average thickness t2 [mm] of the ground contact portion and the average thickness t3 [mm] of the center of the raised bottom portion satisfy the relationship -0.8 < (t2 - t3) / t2 < 0.6.

[0012] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing down onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop will be small, making the glass tube for pharmaceutical containers less likely to break when dropped.

[0013] (4) In any of the above configurations (1) to (3), it is preferable that the average thickness t2 [mm] of the ground contact portion and the minimum thickness t3min [mm] of the raised bottom portion satisfy the relationship 0.4<t2 / t3min<2.6.

[0014] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing downward onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop is small, making the glass tube for pharmaceutical containers less likely to break when dropped.

[0015] (5) In any of the configurations (1) to (4) above, the average thickness t2 [mm] of the ground contact portion and the radial distance ro [mm] from the ground contact point of the ground contact portion to the imaginary extension plane of the outer circumferential surface of the side wall portion are 0.1≦(t2) ３ / (ro × (t1) ２ )≦8 is preferably satisfied.

[0016] This increases the breakage strength of the glass tube for pharmaceutical containers against a drop impact, while facilitating the formation of the shape of the bottom by thermal processing. Furthermore, even when a plurality of glass tubes for pharmaceutical containers are bundled together, the outer surfaces of the tube ends can be prevented from contacting each other. In other words, (t2) ３ / (ro × (t1) ２ If the value of (t2) becomes too large, it may become difficult to form the bottom by thermal processing, which may result in a decrease in productivity. In addition, the grounding portion (grounding point) may be located in a direction away from the tube axis, which may cause contact between the tube ends of the glass tube for pharmaceutical containers, which may result in scratches on the tube ends. On the other hand, if the value of (t2) becomes too large, it may become difficult to form the bottom by thermal processing, which may result in a decrease in productivity. In addition, the grounding portion (grounding point) may be located in a direction away from the tube axis, which may cause contact between the tube ends of the glass tube for pharmaceutical containers, which may result in scratches on the tube ends. ３ / (ro × (t1) ２ If the value of (a) is too small, the glass tube for pharmaceutical containers will be easily broken by the impact of being dropped.

[0017] (6) In any of the configurations (1) to (5) above, the average thickness t1 [mm] of the side wall portion, the average thickness t2 [mm] of the ground contact portion, and the radial distance ro [mm] from the ground contact point of the ground contact portion to the imaginary extension plane of the outer circumferential surface of the side wall portion are 0.1≦(t2) ３ It is preferable that the relationship: / (t1×ro)≦0.8 is satisfied.

[0018] This increases the breakage strength of the glass tube for pharmaceutical containers against a drop impact, while facilitating the formation of the bottom shape by thermal processing. Furthermore, even when multiple glass tubes for pharmaceutical containers are bundled together, the outer surfaces of the tube ends are prevented from contacting each other, making the tube ends less susceptible to scratches.

[0019] (7) In any of the configurations (1) to (6) above, it is preferable that the outer diameter d1 [mm] of the side wall portion and the diameter d2 [mm] of the circle formed by the grounding point of the grounding portion satisfy the relationship d2 / d1≦0.86.

[0020] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing downward onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop is small, making the glass tube for pharmaceutical containers less likely to break when dropped.

[0021] (8) In any of the configurations (1) to (7) above, the average thickness t2 [mm] of the ground contact portion, the average thickness t3 [mm] of the center of the raised bottom, and the radial distance ro [mm] from the ground contact point of the ground contact portion to the outer circumferential surface of the side wall portion are t2 × t3 × ro / (t1). ３ It is preferable that the relationship be satisfied.

[0022] In this way, even if the glass tube for pharmaceutical containers is dropped vertically with its bottom facing downward onto a flat plate, the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers due to the impact of the drop is small, making the glass tube for pharmaceutical containers less likely to break when dropped.

[0023] (9) In any of the above configurations (1) to (8), when a glass tube for pharmaceutical containers is dropped from a height of 450 mm onto a Teflon (registered trademark) plate in a vertical position with its bottom facing downwards, it is preferable that the maximum tensile stress generated on the outer surface of the glass tube for pharmaceutical containers is 55 MPa or less.

[0024] This makes it more unlikely that the glass tube for pharmaceutical containers will break when dropped.

[0025] (10) In any one of the above (1) to (9), the total length of the glass tube for pharmaceutical containers in the tube axis direction is preferably 500 mm or more.

[0026] In this way, the glass tube for pharmaceutical containers can be made sufficiently long, so that a large number of pharmaceutical containers can be produced from a single glass tube for pharmaceutical containers, thereby improving the productivity of pharmaceutical containers.

[0027] (11) In any of the above configurations (1) to (10), both ends of the side wall portion may be sealed.

[0028] This makes it possible to prevent foreign matter from entering the interior of the glass tube for pharmaceutical containers.

[0029] (12) The present invention, which has been invented to solve the above problems, is a method for manufacturing pharmaceutical containers, characterized in that a pharmaceutical container is manufactured by processing a pharmaceutical container glass tube having any of the configurations described above in (1) to (11).

[0030] This prevents glass tubes for pharmaceutical containers from being broken when dropped, thereby improving the productivity of pharmaceutical containers.

[0031] According to the present invention, glass tubes for pharmaceutical containers can be prevented from being broken by impact when dropped.

[0032] 1 is a longitudinal sectional view of a glass tube for pharmaceutical containers according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of FIG. 1. FIG. 3 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of FIG. 1, for explaining a method for calculating the average thickness t1 of the side wall portion. FIG. 4 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of FIG. 1, for explaining a method for calculating the average thickness t2 of the ground portion. FIG. 5 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of FIG. 1, for explaining a method for calculating the average thickness t3 of the center portion of the raised bottom portion. FIG. 6 is a longitudinal sectional view showing, on an enlarged scale, a preparatory step included in a manufacturing method of pharmaceutical containers according to an embodiment of the present invention. FIG. 7 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Example 1. FIG. 8 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Example 2. FIG. 9 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Example 3. FIG. 10 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Example 4. FIG. 11 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Comparative Example 1. FIG. 12 is a longitudinal sectional view showing, on an enlarged scale, a main portion of the glass tube for pharmaceutical containers of Comparative Example 2. 1 is an enlarged longitudinal cross-sectional view showing a main portion of a glass tubular for pharmaceutical containers according to Comparative Example 3. FIG. 2 is an enlarged longitudinal cross-sectional view showing a main portion of a glass tubular for pharmaceutical containers according to Comparative Example 4.

[0033] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0034] 1, a glass tubular container for pharmaceutical containers 1 according to this embodiment includes a cylindrical side wall 2 and a bottom 3 that seals one end of the side wall 2. In this embodiment, the other end of the side wall 2 is not sealed but is open.

[0035] The total length L1 of the glass tubular material 1 for pharmaceutical containers in the tube axis direction Y is preferably 500 to 2500 mm, more preferably 800 to 2000 mm, and even more preferably 1000 to 1800 mm. The outer diameter d1 of the side wall portion 2 is preferably 4 to 60 mm, more preferably 6 to 50 mm, and even more preferably 8 to 40 mm. In other words, the glass tubular material 1 for pharmaceutical containers is a long, thin body that is elongated in the tube axis direction Y.

[0036] The bottom 3 includes a grounding portion 4 connected to one end of the side wall portion 2 and a raised bottom 5 provided inside the grounding portion 4 .

[0037] The grounding portion 4 has a grounding point P that touches the flat plate when the glass tube 1 for pharmaceutical containers is placed on the flat plate in a vertical position. The grounding portion 4 corresponds to a corner of the bottom portion 3 and is an annular region in a plan view (when viewed along the tube axis direction Y).

[0038] The raised bottom 5 is a portion that retracts upward without contacting the flat plate when the pharmaceutical container glass tube 1 is placed on the flat plate in a vertical position. The raised bottom 5 is a circular region in a plan view. The raised bottom 5 may be formed, for example, by a flat portion extending along the radial direction X, or by a convex curved surface with the center positioned at the highest position. In this embodiment, the peripheral edge of the raised bottom 5 is connected to the ground portion 4.

[0039] As shown in FIG. 2 , when the average thickness of the side wall portion 2 is t1 [mm] and the average thickness of the ground portion 4 is t2 [mm], the glass tube 1 for pharmaceutical containers satisfies the following relationship: t2 / t1>1.025 (1)

[0040] Here, the average thickness t1 of the side wall portions 2 is defined as the average value (average value of 40 measurements in total) of thickness measurements taken at 10 locations for each of four types of side wall portions 2 included in any two cross sections passing through the tube axis center line C of the pharmaceutical container glass tubing 1. In this case, as shown in Fig. 3, the glass thickness as viewed in the normal direction from each measurement point M1 on the inner surface 1a of the pharmaceutical container glass tubing 1 (the length of a measurement line ML1 extending from measurement point MP1 in the normal direction to the inner surface 1a and intersecting with the outer surface 1b) is measured. Specifically, for each of the four types of side wall portions 2, the measurement points MP1 for calculating t1 are set as follows: That is, the measurement points MP1 are set to any 10 points on the inner surface of the side wall portion 2 that are at least half the outer diameter d1 away from the ground point P in the tube axis direction Y. For example, on the inner surface of the side wall 2, a total of ten measurement points MP1 are provided at intervals of a distance ΔY (ΔY=0.5 mm) along the tube axis direction Y, starting from a position d1 / 2 away from the ground point P in the tube axis direction Y. In this example, the measurement points MP1 include positions on the inner surface of the side wall 2 that are d1 / 2 away from the ground point P in the tube axis direction Y.

[0041] The average thickness t2 of the ground contact portion 4 is determined as the average value (average of 40 measurements in total) of thicknesses measured at 10 locations for each of four types of ground contact portion 4 included in two cross sections passing through the tube axis center line C of the glass tube 1 for pharmaceutical containers, which were used to measure the average thickness t1 of the sidewall portion 2. In this case, as shown in Fig. 4, the glass thickness as viewed in the normal direction from each measurement point MP2 on the inner surface 1a of the glass tube 1 for pharmaceutical containers (the length of the measurement line ML2 extending from each measurement point MP1 in the normal direction to the inner surface 1a and intersecting with the outer surface 1b) is measured. Specifically, for each of the four types of ground contact portion 4, the measurement point MP2 for calculating t2 is set as follows: That is, a circle TC is set that passes through point Q, which is a distance of ¼ of the outer diameter d1 of the side wall portion 2 outward in the radial direction X from the tube axis center line C; point R, which is a distance of ¼ of the outer diameter d1 upward in the tube axis direction Y from a plane extending in the radial direction X that passes through the grounding point P of the grounding portion 4; and point S, which is on the inner surface of the grounding portion 4. In this case, if the center point of the circle TC is O, point S is the point where the length of the line segment OS is maximum. Then, ten points on the inner surface of the grounding portion 4 that exist within a 45° range to the left and right of the line segment OS based on the center point O are set as measurement points MP2. For example, if measurement points MP2 are set at regular angles (central angles) within a 45° range to the left and right of the line segment OS based on the center point O, a total of ten measurement points MP2 are set on the inner surface of the grounding portion 4 at angle Δα (Δα = 10°) from the position 45° to the left (or 45° to the right) of the line segment OS based on the center point O. In this example, measurement point MP2 includes positions on the inner surface of the ground contact patch 4 that are 45 degrees to the left and 45 degrees to the right of line segment OS, but does not include point S.

[0042] If the relationship of formula (1) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, and as a result, the glass tube 1 for pharmaceutical containers will be less likely to break due to the impact of the drop.

[0043] The lower limit of t2 / t1 is preferably 1.05 or more, more preferably 1.10 or more, and particularly preferably 1.12 or more, from the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping. On the other hand, the upper limit of t2 / t1 is preferably 1.4 or less, more preferably 1.35 or less, and even more preferably 1.30 or less, from the viewpoint of facilitating the forming of the bottom 3 by thermal processing.

[0044] As shown in FIG. 2, when the average thickness of the side wall portion 2 is t1 [mm] and the average thickness of the ground portion 4 is t2 [mm], the glass tube 1 for pharmaceutical containers preferably satisfies the following relationship: (t2-t1) / t1≧0.04 (2)

[0045] If the relationship of formula (2) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0046] The lower limit of (t2-t1) / t1 is preferably 0.1 or more from the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping, while the upper limit of (t2-t1) / t1 is preferably 0.5 or less, more preferably 0.3 or less, from the viewpoint of facilitating the forming of the bottom portion by thermal processing.

[0047] As shown in Fig. 2, when the average thickness of the grounding portion 4 is t2 [mm] and the average thickness of the raised bottom 5 at the center (near the tube axis center line C) is t3 [mm], the glass tube 1 for pharmaceutical containers preferably satisfies the following relationship: 0.4 < t2 / t3 < 2.3 (3)

[0048] Here, the average thickness t3 at the center of the raised bottom 5 is defined as the average value (average of 20 measurements) of thicknesses measured at 10 locations at each of the centers of two types of raised bottoms 5 included in any two cross sections passing through the tube axis center line C of the pharmaceutical container glass tubing 1. In this case, as shown in FIG. 5 , the glass thickness as viewed in the normal direction from each measurement point MP3 on the inner surface 1a of the pharmaceutical container glass tubing 1 (the length of a measurement line ML3 extending from each measurement point MP3 in the normal direction to the inner surface 1a and intersecting with the outer surface 1b) is measured. Specifically, for each of the two types of raised bottoms 5, the measurement points MP3 used to calculate t3 are set as follows: Five measurement points MP3 are set on the inner surface of the raised bottom 5, one on each side of the tube axis center line C. However, of the ten measurement points MP3, the distance between the leftmost and rightmost measurement points is at least ¼ of d1. In detail, for example, on the inner surface of the center of the raised bottom 5, a total of five measurement points MP3 are set along the radial direction X to the right of the tube axis center line C, and a total of five measurement points MP3 are set along the radial direction X to the left of the tube axis center line C. Note that in this example, the measurement points MP3 do not include positions on the tube axis center line C on the inner surface of the raised bottom 5.

[0049] If the relationship of formula (3) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0050] From the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping, the upper limit range of t2 / t3 is preferably 2.0 or less, and even more preferably 1.5 or less, and the lower limit range of t2 / t3 is preferably 0.7 or more, and more preferably 0.8 or more.

[0051] As shown in Figure 2, when the average thickness of the grounding portion 4 is t2 [mm] and the average thickness of the raised bottom 5 at the center (near the tube axis center line C) is t3 [mm], the glass tube 1 for pharmaceutical containers preferably satisfies the following relationship: -0.8<t2-t3<0.5 (4)

[0052] If the relationship of formula (4) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0053] From the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping, the upper limit of the difference between t2 and t3 is preferably 0.35 mm or less, more preferably 0.3 mm or less, and particularly preferably 0.2 mm or less, and the lower limit of the difference between t2 and t3 is preferably −0.6 mm or more, more preferably 0 mm or more, and even more preferably 0.03 mm or more.

[0054] As shown in Figure 2, when the average thickness of the grounding portion 4 is t2 [mm] and the average thickness of the raised bottom 5 at the center (near the tube axis center line C) is t3 [mm], the glass tube 1 for pharmaceutical containers preferably satisfies the following relationship: -0.8<(t2-t3) / t2<0.6 (5)

[0055] If the relationship of formula (5) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0056] From the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping, the upper limit range of (t2-t3) / t2 is more preferably 0.35 or less, further preferably 0.3 or less, and particularly preferably 0.2 or less, and the lower limit range of (t2-t3) / t2 is preferably -0.6 or more, more preferably 0 or more, and further preferably 0.03 or more.

[0057] As shown in Fig. 2, when the average thickness of the ground contact portion 4 is t2 [mm] and the minimum thickness of the raised bottom portion 5 is t3min [mm], the glass tube 1 for pharmaceutical containers preferably satisfies the following relationship: 0.4 < t2 / t3min < 2.6 (6)

[0058] Here, the minimum thickness t3min of the raised bottom 5 is the value measured for the thickness of the thinnest portion of the raised bottom 5 included in two cross sections passing through the tube axis center line C of the glass tube 1 for pharmaceutical containers, which were used to measure the average thickness t1 of the sidewall portion 2. In this case, the glass thickness measured is the thickness of the glass viewed in the normal direction from a certain point on the inner surface 1a of the glass tube 1 for pharmaceutical containers. The portion of the raised bottom 5 with the minimum thickness t3min may be formed in the center of the raised bottom 5, or may be formed between the center and the peripheral portion (the connecting portion between the raised bottom 5 and the ground portion 4) of the raised bottom 5.

[0059] If the relationship of formula (6) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0060] From the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken by dropping, the upper limit of t2 / t3min is preferably 2.2 or less, further preferably 1.8 or less, and particularly preferably 1.5 or less, while the lower limit of t2 / t3min is preferably 0.6 or more, more preferably 0.8 or more, and further preferably 1.0 or more.

[0061] As shown in Fig. 2, when the average thickness of the grounding portion 4 is t2 [mm] and the radial distance from the grounding point P of the grounding portion 4 to the outer circumferential surface of the side wall portion 2 (strictly speaking, the imaginary extension plane of the outer circumferential surface of the side wall portion 2) is ro [mm], the glass tube for pharmaceutical containers 1 preferably satisfies the following relationship: 0.1 < (t2) ３ / (ro × (t1) ２ )≦8 (7)

[0062] If the relationship of formula (7) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated on the outer surface 1b of the glass tube 1 for pharmaceutical containers due to the impact of the drop will be small. As a result, the glass tube 1 for pharmaceutical containers is less likely to break when dropped. In addition, the bottom 3 can be easily formed by thermal processing. Furthermore, even if multiple glass tubes for pharmaceutical containers 1 are bundled together, the outer surfaces of the tube ends can be prevented from contacting each other, making the tube ends less likely to be damaged.

[0063] (t2) ３ / (ro × (t1) ２ When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the upper limit of (t2) is more preferably 3 or less, even more preferably 1.03 or less, and particularly preferably 0.9 or less, from the viewpoints of facilitating the thermal forming of the bottom portion 3 of the glass tube 1 for pharmaceutical containers and preventing scratches on the outer surface of the tube end portion even when bundled, when the average thickness t1 of the side wall portion 2 is 0.9 mm or more. ３ / (ro × (t1) ２ When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the upper limit of (t2) is more preferably 3 or less, even more preferably 1.0 or less, and particularly preferably 0.9 or less, from the viewpoints of facilitating the thermal forming of the bottom 3 of the glass tube for pharmaceutical containers 1 and preventing scratches on the outer surface of the tube end portion even when bundled. ３ / (ro × (t1) ２ When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the lower limit of (t2) is more preferably 0.3 or more, even more preferably 0.65 or more, and particularly preferably 0.7 or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped. ３ / (ro × (t1) ２ When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the lower limit of the ratio (t1) is more preferably 0.2 or more, even more preferably 0.25 or more, and particularly preferably 0.3 or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped.

[0064] Assuming that the average thickness of the side wall portion 2 is t1 [mm], the average thickness of the ground portion 4 is t2 [mm], and the radial distance from the ground point P of the ground portion 4 to the side wall portion 2 is ro [mm], the glass tube 1 for pharmaceutical containers satisfies the following relationship: 0.1≦(t2) ３ / (t1 × ro)≦2.5 (8)

[0065] If the relationship of formula (8) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated on the outer surface 1b of the glass tube 1 for pharmaceutical containers due to the impact of the drop will be small. As a result, the glass tube 1 for pharmaceutical containers is less likely to break when dropped. In addition, the shape of the bottom 3 can be easily formed by thermal processing. Furthermore, even if multiple glass tubes for pharmaceutical containers are bundled together, the outer surfaces of the tube ends can be prevented from contacting each other, making the tube ends less likely to be damaged.

[0066] (t2) ３ When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the upper limit range of (t2) / (t1×ro) is more preferably 1.0 mm or less, even more preferably 0.9 mm or less, and particularly preferably 0.8 mm or less, from the viewpoints of facilitating the thermal forming of the bottom portion 3 of the glass tube 1 for pharmaceutical containers and preventing scratches on the outer surfaces of the tube ends even when bundled. ３ When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the upper limit range of (t1 × ro) is more preferably 0.9 mm or less, even more preferably 0.8 mm or less, and particularly preferably 0.7 mm or less, from the viewpoints of facilitating the thermal forming of the bottom portion 3 of the glass tube 1 for pharmaceutical containers and preventing scratches on the outer surface of the tube end portion even when bundled, when the average thickness t1 of the side wall portion 2 is less than 0.9 mm. ３ When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the lower limit of (t2) / (t1×ro) is preferably 0.2 mm or more, more preferably 0.5 mm or more, and even more preferably 0.7 mm or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from being broken when dropped. ３When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the lower limit of / (t1 × ro) is preferably 0.2 mm or more, more preferably 0.25 mm or more, and even more preferably 0.3 mm or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped.

[0067] 1 and 2, when the outer diameter of the side wall portion 2 is d1 [mm] and the diameter of the circle formed by the grounding point P of the grounding portion 4 is d2 [mm], the glass tube 1 for pharmaceutical containers satisfies the following relationship: d2 / d1≦0.86 (9)

[0068] If the relationship of formula (8) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0069] From the viewpoint of preventing the pharmaceutical container glass tube 1 from being broken when dropped, the upper limit of d2 / d1 is preferably 0.85 or less, and the lower limit of d2 / d1 is preferably 0.4 or more, more preferably 0.5 or more.

[0070] As shown in Fig. 2, when the average thickness of the ground contact portion 4 is t2 [mm], the average thickness of the raised bottom 5 at the center is t3 [mm], and the radial distance from the ground contact point P of the ground contact portion 4 to the outer circumferential surface of the side wall portion 2 is ro [mm], the glass tube 1 for pharmaceutical containers satisfies the following relationship: t2 x t3 x ro / (t1). ３ >0.3 (10)

[0071] If the relationship of formula (10) is satisfied, even if the glass tube 1 for pharmaceutical containers is dropped vertically with the bottom 3 facing downward onto a flat plate, the maximum tensile stress Tmax generated in the outer surface 1b of the glass tube 1 due to the impact of the drop will be small, making the glass tube 1 for pharmaceutical containers less likely to break when dropped.

[0072] t2×t3×ro / (t1) ３When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the lower limit of t2×t3×ro / (t1) is more preferably 0.8 or more, even more preferably 1.5 or more, and particularly preferably 2 or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped. ３ When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the lower limit of t2×t3×ro / (t1) is more preferably 0.7 or more, even more preferably 2 or more, and particularly preferably 3 or more, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped. ３ When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the upper limit range of t2 × t3 × ro / (t1) is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less, from the viewpoint of facilitating molding by thermal processing. ３ When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the upper limit range of is preferably 5 or less, more preferably 4 or less, and even more preferably 3.8 or less, from the viewpoint of facilitating molding by thermal processing.

[0073] As shown in FIG. 2 , the angle θ of the inner surface of the grounding portion 4 is preferably 50 to 90°, more preferably 55 to 80°, and even more preferably 60 to 70°. If the angle θ of the inner surface of the grounding portion 4 is too small, it becomes difficult to form the bottom portion 3 by thermal processing. On the other hand, if the angle θ of the inner surface of the grounding portion 4 is too large, the bottom portion 3 is more susceptible to impact when dropped, which may make it difficult to prevent breakage. Here, the angle θ is defined as the angle between a tangent LQ to the inner surface of the bottom portion 3 at a point Q that is a distance of ¼ of the outer diameter d1 of the side wall portion 2 outward in the radial direction X from the tube axial centerline C, and a tangent LR to the inner surface of the side wall portion 2 at a point R that is a distance of ¼ of d1 upward in the tube axial direction Y from a plane extending in the radial direction X that passes through the grounding point P of the grounding portion 4.

[0074] When the average thickness t1 of the side wall portion 2 is 0.9 mm or more, the average thickness t2 of the grounding portion 4 is preferably 0.6 to 1.4 mm, more preferably 0.8 to 1.3 mm, and particularly preferably 0.9 to 1.2 mm, from the viewpoint of preventing the glass tube for pharmaceutical containers 1 from being dropped and broken. When the average thickness t1 of the side wall portion 2 is less than 0.9 mm, the average thickness t2 of the grounding portion 4 is preferably 0.3 to 1.1 mm, more preferably 0.4 to 1.0 mm, and particularly preferably 0.50 to 0.95 mm, from the viewpoint of preventing the glass tube for pharmaceutical containers 1 from being dropped and broken.

[0075] When the average thickness t1 of the side wall 2 is 0.9 mm or more, the average thickness t3 of the raised bottom 5 at the center is preferably 0.6 to 1.4 mm, more preferably 0.8 to 1.3 mm, and particularly preferably 0.9 to 1.2 mm, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped. When the average thickness t1 of the side wall 2 is less than 0.9 mm, the average thickness t3 of the raised bottom 5 at the center is preferably 0.3 to 1.1 mm, more preferably 0.4 to 1.0 mm, and particularly preferably 0.50 to 0.95 mm, from the viewpoint of preventing the glass tube 1 for pharmaceutical containers from breaking when dropped.

[0076] When the pharmaceutical container glass tube 1 having the above configuration is dropped from a height of 450 mm onto a flat plate in a vertical position with the bottom 3 facing downward, the maximum tensile stress Tmax generated on the outer surface 1b is preferably 55 MPa or less. The maximum tensile stress Tmax is a value determined by simulation. In the simulation, the length L1 of the pharmaceutical container glass tube 1 is 1500 mm, and the flat plate onto which it is dropped is a Teflon (registered trademark) plate. The simulation can be performed, for example, by time history response analysis using the finite element method. When using commercially available general-purpose FEM software, for example, Abaqus (manufactured by Dassault Systèmes), ANSYS Mechanical (manufactured by ANSYS), or Marc (manufactured by MSC) can be used.

[0077] The maximum tensile stress Tmax generated on the outer surface 1b of the glass tube 1 for pharmaceutical containers due to a drop impact is more preferably 50 MPa or less, further preferably 45 MPa or less, and particularly preferably 43 MPa or less.

[0078] (Method for Manufacturing Glass Tubing for Pharmaceutical Containers) The method for manufacturing the glass tubing 1 for pharmaceutical containers having the above-described configuration includes a preparation step of preparing a long original glass tube formed by the Danner method or the like, a sealing step of heating and sealing one opening end of the original glass tube with a burner, and a thermal processing step of thermally processing the sealed portion into a shape corresponding to the bottom 3 of the glass tubing 1 for pharmaceutical containers. In the thermal processing step, the sealed portion of the original glass tube may be heated with a burner while the sealed opening end faces upward. By doing so, the center of the softened sealed portion bends downward due to gravity, forming the bottom 3 having the ground portion 4 and the raised bottom 5. Alternatively, the bottom 3 having the ground portion 4 and the raised bottom 5 may be formed by applying pressure from the outside to the inside of the tube to the sealed opening end with a pressing member during or immediately after heating with the burner.

[0079] The heating time with a burner in the thermal processing step is preferably 1 to 60 seconds, more preferably 3 to 45 seconds.

[0080] (Method for Manufacturing Pharmaceutical Containers) In the method for manufacturing pharmaceutical containers according to this embodiment, the pharmaceutical container glass tubing 1 having the above-described configuration is processed to manufacture pharmaceutical containers. Examples of pharmaceutical containers include ampoules, syringes, and vials.

[0081] In detail, the method for manufacturing pharmaceutical containers includes a preparation step of setting the glass tubing 1 for pharmaceutical containers in a vertical position with the bottom 3 facing downward, a cutting step of heating a part of the glass tubing 1 for pharmaceutical containers in the vertical position with a burner and cutting it to a predetermined length to obtain a container intermediate, and a thermal processing step of heating the end of the container intermediate with a burner to form it into a predetermined shape to obtain a pharmaceutical container. In this way, a plurality of pharmaceutical containers are successively manufactured from a single glass tubing 1 for pharmaceutical containers.

[0082] As shown in Figure 6, in the preparation step, the glass tube 1 for pharmaceutical containers in a vertical position may be dropped onto a flat plate 6 with the bottom 3 facing downwards to set the glass tube 1 for pharmaceutical containers in a predetermined position. Even in this case, the glass tube 1 for pharmaceutical containers is less likely to break even when subjected to a drop impact due to collision with the flat plate 6, because the shape of the bottom 3 is regulated as described above. This improves the productivity of pharmaceutical containers. Note that the bottom 3 of the glass tube 1 for pharmaceutical containers is removed in the initial cutting step, and therefore the bottom 3 of the glass tube 1 for pharmaceutical containers does not remain in the manufactured pharmaceutical containers.

[0083] Although the embodiment of the present invention has been described, the embodiment of the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention.

[0084] In the above embodiment, one end of the side wall 2 of the glass tubular container 1 is sealed with the bottom 3, while the other end of the side wall 2 is open and not sealed. However, this is not limiting. Both ends of the side wall 2 of the glass tubular container 1 may be sealed. This prevents foreign matter from entering the glass tubular container before the glass tubular container 1 is used to manufacture the medical container. This allows the manufacture of highly clean medical containers. When both ends of the side wall 2 of the glass tubular container 1 are sealed, the bottom 3 having the above-described shape may be formed on both ends of the side wall 2, or the bottom 3 having the above-described shape may be formed on only one end of the side wall 2.

[0085] The method for manufacturing a glass article according to the present invention will be described below based on examples. Note that the following examples are merely illustrative and the present invention is not limited to the following examples in any way.

[0086] Glass tubes for pharmaceutical containers shown in Figures 7 to 10 were prepared as Examples 1 to 4, and glass tubes for pharmaceutical containers shown in Figures 11 to 14 were prepared as Comparative Examples 1 to 4. The glass tubes for pharmaceutical containers shown in Examples 1 to 4 were prepared by extending and adjusting the heating time with a burner in the range of 1.1 to 2 times longer than the glass tubes for pharmaceutical containers of Comparative Examples 1 to 4. Shape data was measured for each of these glass tubes for pharmaceutical containers. The results are shown in Table 1.

[0087]

[0088] In Table 1, t1 is the average thickness of the side wall portion, t2 is the average thickness of the ground contact portion, t3 is the average thickness of the raised bottom portion at the center, t3min is the minimum thickness of the raised bottom portion, ro is the radial distance from the ground contact point of the ground contact portion to the outer peripheral surface of the side wall portion, d1 is the outer diameter of the side wall portion, d2 is the diameter of the circle formed by the ground contact points of the ground contact portion, θ is the angle of the inner surface of the ground contact portion, and Tmax is the maximum tensile stress (simulation) generated in the outer surface of the tubular glass for pharmaceutical containers due to a drop impact.

[0089] The results in Table 1 also confirm that the glass tubes for pharmaceutical containers according to Examples 1 to 4 have t2 / t1 ratios greater than 1.025, and the maximum tensile stress Tmax generated in the outer surface of the glass tubes for pharmaceutical containers upon impact is as small as 50 MPa or less. On the other hand, the glass tubes for pharmaceutical containers according to Examples 1 to 4 have t2 / t1 ratios less than 1.025, and the maximum tensile stress Tmax generated in the outer surface of the glass tubes for pharmaceutical containers upon impact is as large as 50 MPa. Therefore, the simulation results also suggest that the glass tubes for pharmaceutical containers according to Comparative Examples 1 to 4 are more susceptible to drop breakage, while the glass tubes for pharmaceutical containers according to Examples 1 to 4 are less susceptible to drop breakage.

[0090] Therefore, drop tests were actually conducted on the glass tubes for pharmaceutical containers according to Examples 1 to 4 and Comparative Examples 1 to 4 to evaluate the number of breakages. In the drop test, the glass tubes for pharmaceutical containers were dropped from a height of 450 mm onto a Teflon (registered trademark) plate in a vertical position with their bottoms facing downwards within a guide tube that guides the outer surface of the sidewall of the glass tubes for pharmaceutical containers. This drop test was conducted 20 times (20 tubes) for each of the glass tubes for pharmaceutical containers according to Examples 1 to 4 and Comparative Examples 1 to 4. The results are shown in Table 2.

[0091]

[0092] As shown in Table 2, the drop tests actually conducted resulted in breakage of the glass tubes for pharmaceutical containers according to Comparative Examples 1 to 4, but good results were obtained in that no breakage occurred in the glass tubes for pharmaceutical containers according to Examples 1 to 4. Therefore, the actual drop tests also yielded results similar to the simulation results for the maximum tensile stress Tmax caused by drop impact.

[0093] REFERENCE SIGNS LIST 1: Glass tube for pharmaceutical containers 2: Side wall 3: Bottom 4: Grounding portion 5: Raised bottom P: Grounding point C: Tube axis center line X: Radial direction Y: Tube axis direction t1: Average thickness of side wall t2: Average thickness of grounding portion t3: Average thickness at the center of raised bottom θ: Angle of inner surface of grounding portion

Claims

1. A glass tube for medical containers comprising a cylindrical side wall and a bottom sealing one end of the side wall, wherein the bottom comprises a grounding portion connected to the one end of the side wall and a raised bottom provided inside the grounding portion, and wherein an average thickness t1 [mm] of the side wall and an average thickness t2 [mm] of the grounding portion satisfy the relationship t2 / t1>1.

025.

2. A glass tube for pharmaceutical containers according to claim 1, wherein an average thickness t2 [mm] of the grounding portion and an average thickness t3 [mm] of the raised bottom at the center satisfy the relationship: -0.8<(t2-t3)<0.

5.

3. A glass tube for pharmaceutical containers according to claim 1 or 2, wherein an average thickness t2 [mm] of the grounding portion and an average thickness t3 [mm] of the raised bottom at the center satisfy the relationship: -0.8<(t2-t3) / t2<0.

6.

4. A glass tube for pharmaceutical containers according to claim 1 or 2, wherein an average thickness t2 [mm] of the grounding portion and a minimum thickness t3min [mm] of the raised bottom portion satisfy the relationship: 0.4<t2 / t3min<2.

6.

5. The average thickness t2 [mm] of the grounding portion and the radial distance ro [mm] from the grounding point of the grounding portion to the outer circumferential surface of the side wall portion are 0.1≦(t2). ３ / (ro × (t1) ２ 3. The glass tube for pharmaceutical containers according to claim 1 or 2, which satisfies the relationship:

6. The average thickness t1 [mm] of the side wall portion, the average thickness t2 [mm] of the ground contact portion, and the radial distance ro [mm] from the ground contact point of the ground contact portion to the imaginary extension plane of the outer circumferential surface of the side wall portion are 0.1≦(t2) ３ 3. The glass tube for pharmaceutical containers according to claim 1 or 2, which satisfies the relationship: / (t1×ro)≦0.

8.

7. A glass tube for pharmaceutical containers according to claim 1 or 2, wherein an outer diameter d1 [mm] of the side wall portion and a diameter d2 [mm] of a circle formed by the grounding point of the grounding portion satisfy the relationship d2 / d1≦0.

86.

8. The average thickness t2 [mm] of the ground contact portion, the average thickness t3 [mm] of the center of the raised bottom, and the radial distance ro [mm] from the ground contact point of the ground contact portion to the imaginary extension plane of the outer circumferential surface of the side wall portion are t2 × t3 × ro / (t1). ３ 3. The glass tube for pharmaceutical containers according to claim 1 or 2, which satisfies the relationship: >0.

3.

9. A glass tube for pharmaceutical containers as claimed in claim 1 or 2, in which when the glass tube for pharmaceutical containers in a vertical position with the bottom facing down is dropped from a height of 450 mm onto a Teflon plate, the maximum tensile stress generated in the outer surface of the glass tube for pharmaceutical containers is 55 MPa or less.

10. The glass tube for pharmaceutical containers according to claim 1 or 2, wherein the total length in the axial direction of the tube is 500 mm or more.

11. The glass tube for pharmaceutical containers according to claim 1 or 2, wherein both ends of said side wall portion are sealed.

12. A method for producing pharmaceutical containers, comprising processing the glass tube for pharmaceutical containers according to claim 1 or 2 to produce pharmaceutical containers.

Images