JP3959367B2 - Glass container coating method and glass container - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coating method for imparting lubricity and scratch resistance to the outer surface of a glass container such as a glass bottle, a glass container having a coating film formed on the outer surface by this coating method, and a spray nozzle suitable for use in this coating method. About.
[0002]
[Prior art]
Conventionally, coating (so-called cold end coating) is performed in which a coating agent is applied to the outer surface of a glass container in the vicinity of the outlet of a slow cooling furnace (so-called cold end). By performing such coating, the glass container is provided with slipperiness and scratch resistance, and the strength of the bottle is improved. The coating agent is obtained by dispersing these fine particles in water by adding a surfactant to a solid lubricant such as polyethylene, polyethylene wax, modified polyethylene wax, carnauba wax and the like to form an emulsion.
[0003]
When the above cold end coating is performed, so-called hot end coating is often performed as a pretreatment. This is because a tin compound (mainly tin tetrachloride) or a titanium compound (mainly titanium tetrachloride) is allowed to act on the outer surface of a high-temperature glass container immediately after molding near the entrance of the slow cooling furnace, and tin oxide or A titanium oxide film is formed. By performing hot end coating, the adhesion of the cold end coating film to the glass surface is improved. In many cases, a glass container such as a glass bottle is attached with a label after the hot end coating and the cold end coating are performed.
[0004]
Usually, the hydrophilicity and adhesiveness of glue are worse than the glass surface in the coating film which performed the cold end coating by said coating agent. Japanese Patent Application Laid-Open Nos. 2001-302284 and 2001-328613 disclose techniques for improving the hydrophilicity and adhesiveness of the coating film of the above coating agent.
[0005]
[Problems to be solved by the invention]
On the other hand, when the used glass container is collected and the glass is recycled, it is necessary to peel off the label attached to the glass container. Accordingly, there is a need for a glass container outer surface treatment that can easily peel off the label adhered to the outer surface of the glass container (easy peelability). The coating film of the above coating agent is also required to be easily peelable from the label.
[0006]
When coating a glass container with a solid lubricant, in order to improve easy peelability, it is conceivable to perform coating with a coating agent in which an easily peelable substance is added to the outer surface of the glass container. As shown in FIG. 1, normally, the coating agent is sprayed downward from the upper side of the glass container G with a spray nozzle 13 to apply the coating agent to almost the entire outer surface (excluding the mouth and bottom) of the glass container. It is something to apply. A spray nozzle for coating is disclosed in JP-A No. 2002-66389.
[0007]
As described above, when the coating agent is sprayed on almost the entire outer surface of the glass container, it is very difficult to uniformly apply the coating agent to the entire surface. That is, the coating agent tends to be thickly applied to the shoulder portion of the glass container and tends to be thinly applied to the lower portion of the trunk portion. In addition, the manner in which each glass container is applied is not constant, and application unevenness inevitably occurs.
[0008]
It can be said that imparting easy peelability to a glass container is a very difficult request in the first place. That is, if the easy peelability is too large (the adhesive strength of the label is too small), the label tends to peel off during use of the glass container, and this is not allowed. Moreover, when easy peelability is small (the adhesive strength of the label is large), it becomes difficult to remove the label after using the glass container. That is, it can be said that the required easy peelability range (the range of the adhesive strength of the label) is a very small range.
[0009]
In the solid lubricant coating process, in order to achieve suitable easy peelability, factors such as the concentration of the easily peelable substance added to the coating agent, the selection and arrangement of the spray nozzle, and the flow rate of the coating agent are complicatedly entangled. Since the application unevenness of the coating agent is large, there is a large proportion of defective products having an inappropriate label adhesion strength, resulting in poor yield.
[0010]
As shown in FIG. 1, the coating agent containing an easily peelable substance was spray-applied from the spray nozzle 13 to almost the entire outer surface (excluding the mouth and bottom) of the glass container. The coating agent is polyethylene 0.2 mass%, easily peelable material (3-methacryloxypropyltrimethoxysilane) 0.2-0.4 mass%, water 99.4-99.6 mass%, and the adhesive strength of the label is The concentration of the easily peelable substance was adjusted so as to be optimum, and the spray application was performed by adjusting the spray amount and the position of the spray nozzle. A label was affixed to the outer surface of the glass container coated in this way with starch paste. About 10% of the glass container had an inadequate label adhesive strength and was defective.
[0011]
The present invention has been made in order to develop a method for coating a glass container that is easy to form a coating film having a suitable label adhesion strength.
[0012]
[Means for Solving the Problems]
The invention of claim 1 of the present application includes a step of applying a first coating agent containing a solid lubricant on the outer surface of the glass container in the vicinity of the outlet of the slow cooling furnace in the manufacturing process of the glass container, and a label adhered to the outer surface of the glass container. a second coating agent containing a silane coupling agent is easy peelability agent that imparts a property of easily peelable 0.01 to 1 mass%, to the coating fabric sideways towards the body of the glass container with a spray nozzle And a step of coating the glass container.
[0013]
The present application is characterized by performing cold end coating in two steps. The first coating agent can be exactly the same as a conventional coating agent containing a solid lubricant. Such coating agents usually contain a small amount of a surfactant to disperse the solid lubricant in water. This coating is performed on almost the entire outer surface of the glass container as in the prior art. At this time, uneven application of the coating agent may occur, but it does not matter. By the coating treatment with the first coating agent, lubricity and scratch resistance are imparted to the outer surface of the glass container.
[0014]
Although the 2nd coating agent contains an easily peelable substance, what added the easily peelable substance to the conventional coating agent may be used. Since this coating only needs to be performed on the part (usually the body part) to which the label is applied, the coating unevenness of the coating agent is reduced, the probability that the desired easy peeling performance can be realized is high, and the yield is improved. Moreover, the adjustment for realizing the desired easy peelability is simplified. That is, if the easy peelability is too small, it is usually necessary to increase the concentration of the easily peelable substance in the second coating agent or adjust the flow rate of the spray. If the easy peelability is too high, The reverse adjustment may be performed.
[0015]
In the present invention, the temperature of the glass container in the vicinity of the outlet of the slow cooling furnace is not particularly limited, and may be as usual (around 100 ° C.). As a method for applying the first coating agent, an appropriate method such as spraying, brushing, or pickling can be employed. In the case of spraying, the flow rate of the coating agent is suitably about 25 to 500 ml / min. As a method for applying the second coating agent, spray spraying is preferred in which the coating agent can be sprayed with a targeted vertical width on the targeted portion (labeled portion) of the glass container. Drying of the coating agent after coating may be natural drying or forced drying, but natural drying is usually sufficient.
[001 6 ]
Silane coupling agent of the general formula _{YSi (CH 3)} represented by _{3-n X} n, _X is a halogen, OR (alkoxy) or hydrogen chloride, organic residues and Y is capable of reacting with an organic compound such as a polymer Groups such as vinyl, methacryl, epoxy, amino, mercapto groups. As the silane coupling agent, for example, the following can be used.
Vinyltrimethoxysilane,
Vinyltriethoxysilane,
2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane,
3-glycidoxypropyltrimethoxysilane,
3-glycidoxypropylmethyldiethoxysilane,
3-glycidoxypropyltriethoxysilane,
p-styryltrimethoxysilane,
3-methacryloxypropylmethyldimethoxysilane,
3-methacryloxypropyltrimethoxysilane,
3-methacryloxypropylmethyldiethoxysilane,
3-methacryloxypropyltriethoxysilane,
3-acryloxypropyltrimethoxysilane,
N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane,
N-2 (aminoethyl) 3-aminopropyltrimethoxysilane,
N-2 (aminoethyl) 3-aminopropyltriethoxysilane,
3-aminopropyltrimethoxysilane,
3-aminopropyltriethoxysilane,
3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine,
N-phenyl-3-aminopropyltrimethoxysilane,
N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride,
Special aminosilane,
3-ureidopropyltriethoxysilane,
3-chloropropyltrimethoxysilane,
3-mercaptopropylmethyldimethoxysilane,
3-mercaptopropyltrimethoxysilane,
Bis (triethoxysilylpropyl) tetrasulfide,
3-isocyanatopropyltriethoxysilane,
[001 7 ]
A suitable concentration of the silane coupling agent is 0.01 to 1 mass%. If it is less than 0.01 mass%, the effect of imparting easy peelability is small, and if it is more than 1 mass%, the adhesive strength of the label becomes too weak.
[00 18 ]
Silane coupling agent contained in the coating agent of the present invention, a silanol group SiOH Nearby hydrophobic organic residue Y are bound by hydrolysis, silanol groups bonded to the glass, while the hydrophobic organic residue Y Is exposed on the surface of the coating film and contacts the glue applied on the coating film to impart easy peelability.
[0019]
The invention according to claim 2 of the present application is the coating method according to claim 1, wherein the second coating agent contains 0.1 to 1 mass % of silicone as the easily peelable substance . It is a coating method.
[002 0 ]
Silicone is a general term for (RnSiO _{(4-n) / 2} ) _n, a polymer having a main chain composed of a siloxane bond and having a side chain of an organic group bonded to Si. For example, polydimethylsiloxane can be used. Silicone has low biotoxicity, so it can be safely added to the coating agent for food glass containers.
[002 1 ]
The coating film formed by coating a solid lubricant coating agent that does not contain a conventional easily peelable material has slight unevenness on the surface, but when silicone is added, the silicone particles are very fine, so the coating film The coating surface is smoothed and the adhesiveness of the adhesive is slightly reduced. Further, since the silicone itself has non-tackiness, the adhesiveness of the adhesive is also lowered by exposing the silicone particles to the surface of the coating film. Therefore, by adding an appropriate amount of silicone to the solid lubricant coating agent, the label can be removed from the glass container when trying to force it off while maintaining the adhesiveness of the label so that it does not become a problem during normal use. It can be easily peeled off. Moreover, the lubricity of a coating film increases by adding silicone.
[002 2 ]
When adding silicone, it is appropriate that the amount of silicone added is 0.1 to 1 mass% in terms of bottle strength, scratch resistance, slipperiness, and easy peelability of the label.
[002 3 ]
The invention of claim 3 of the present application is the coating method of claim 1 or 2 , wherein the second coating agent contains a solid lubricant. The second coating agent may contain a solid lubricant.
[002 4 ]
According to a fourth aspect of the present invention, in the coating method according to any one of the first to third aspects, the solid lubricant of the first or second coating agent is polyethylene, polyethylene wax, modified polyethylene wax or carnauba wax. This is a method for coating a glass container.
[002 5 ]
Thus, as the solid lubricant of the first coating agent and the solid lubricant used in the second coating agent, those conventionally known can be used. Two or more solid lubricants may be mixed. In the coating agent of the present invention, a surfactant may be added in order to disperse the fine particles of the solid lubricant in water and form an emulsion. As the surfactant, for example, a conventional one such as potassium oleate can be used. Furthermore, other additives such as a solid plasticizer may be added in the same manner as a conventional solid lubricant coating agent.
[002 6 ]
The invention according to claim 5 of the present application is the coating method according to any one of claims 1 to 4 , wherein the concentration of the solid lubricant in the first coating agent is 0.01 to 10 mass%, and the solid lubricant in the second coating agent. The glass container coating method is characterized in that the concentration is 0 to 2 mass%.
[002 7 ]
When the concentration of the solid lubricant is less than 0.01 mass%, the effect of imparting lubricity and scratch resistance to the glass surface is reduced, and when it exceeds 10 mass%, the viscosity of the coating agent is excessively increased and applied to the glass surface. It becomes difficult.
[00 28 ]
The invention according to claim 6 of the present application is the coating method according to any one of claims 1 to 5 , wherein the step of applying the second coating agent includes a gas inlet and a liquid inlet formed in the nozzle body. This is a two-fluid nozzle that supplies liquid and mixes in the mixing chamber inside the nozzle body and sprays the mist mixed with gas and liquid from the discharge port. And it is a coating method of the glass container characterized by performing by the spray nozzle which provided the nozzle tip which has a horizontal slit-shaped discharge port in the lower end of a tubular part.
[00 29 ]
The above-mentioned spray nozzle can insert a long and narrow tubular portion from the top to the barrel portion of the glass container, and the discharge port is a slit in the horizontal direction, so that the sprayed mist spreads in the vertical direction. Since it is restricted, the second coating agent can be sprayed from the side of the barrel of the glass container with the targeted vertical width on the targeted portion (labeled portion).
[003 0 ]
Invention of Claim 7 of this application is a glass container which formed the coating film in the outer surface with the coating method in any one of Claims 1-6 .
[003 1 ]
The glass container with the coating film formed on the outer surface by the coating method of the present application has the desired easy peelability, so the label does not peel off during use, and the label can be easily peeled off after use. To contribute.
[003 2 ]
The invention of claim 8 of the present application is the glass container of claim 7 , wherein in the step of applying the second coating agent, the second coating agent is thick at the center in the vertical direction of the labeling portion of the glass container, The glass container is characterized in that it is thinly applied to the upper and lower end portions, and the coating film of the second coating agent is formed thick at the center portion in the vertical direction of the label attaching portion and thinly at the upper and lower end portions.
[003 3 ]
Since this glass container has the above-described configuration, the center part in the vertical direction of the label is easily peeled off, and the upper end part and the lower end part are not easily peeled off. Therefore, an accident in which the label is peeled off during use of the glass container is unlikely to occur, and if the upper end or a part of the lower end of the label is peeled off after use, the entire label can be easily peeled thereafter.
[003 4 ]
DETAILED DESCRIPTION OF THE INVENTION
The first coating agent was sprayed by the spray nozzle 13 that sprays downward as shown in FIG. 1 immediately downstream of the outlet of the slow cooling furnace in the manufacturing process of the glass container G. The first coating agent is a water emulsion solution of polyethylene + surfactant 0.2 mass% and water 99.8 mass%. Immediately downstream thereof, the second coating agent was applied by spraying with a spray nozzle 1 spraying sideways as shown in FIG. The second coating agent is a water emulsion of polyethylene + surfactant 0.05 mass%, silane coupling agent (3-methacryloxypropyltrimethoxysilane) 0.4 mass%, and water 99.55 mass%. The second coating agent is thickly applied from the side of the barrel of the glass container G to the center in the vertical direction of the label affixing portion of the glass container G by the spray nozzle 1 and thinly applied to the upper and lower ends. The coating film is thick at the center in the vertical direction of the label affixing portion and thin at the upper and lower ends.
[003 5 ]
FIG. 3 is an explanatory view of the glass container G to which the first and second coating agents are applied as described above. A coating film 20 made of the first coating agent is formed on almost the entire outer surface of the glass container G (excluding the mouth and bottom). The coating film 21 of the second coating agent is thick at the center in the vertical direction of the label affixing portion, and is formed thinner toward the upper and lower ends. The label 22 was pasted on the label pasting portion of the glass container G with starch paste. Since an easily peelable substance is added to the coating film 21 of the second coating agent, the center portion in the vertical direction of the label 22 is easily peeled off, and the upper end portion and the lower end portion are not easily peeled off. Almost 100% of the glass container G was sufficiently resistant to normal packaging, transportation and use of the glass container G, and the label was not peeled off. When the label was peeled off, the upper end or lower end of the label was caused by a small amount with a nail or the like, and it was easily peeled off from the glass container without breaking the entire label by picking it off with a finger and peeling it off.
[00 36 ]
As shown in FIG. 4, the nozzle 1 includes a liquid inlet 2, a gas inlet 3, a pilot air inlet 4, a mixing chamber 5, a tubular portion 6, a nozzle tip 7, a discharge port 8, a piston 9, and a coil spring 10. Have. The liquid inlet 2 is for the spray liquid, the gas inlet 3 is the spray air for mixing with the spray liquid, and the pilot air inlet 4 is the part where the pilot air for turning on / off the spray flows. (Not shown) are connected. FIG. 4 shows an ON state. In this state, the spray liquid reaches the nozzle tip 7 through the mixing chamber 5 and the tubular portion 6 as indicated by the arrow A, and the spray air flows from the inside of the piston 9 as indicated by the arrow B. It reaches the nozzle tip 7 through the mixing chamber 5 and the tubular portion 6. That is, the spray liquid and the spray air are mixed in the mixing chamber 5, reach the nozzle tip 7 from the elongated tubular portion 6, and are ejected from the discharge port 8 at the lower end to spray the spray liquid. The pilot air is for turning on / off the spray. In the on state, the pilot air is not supplied and the piston 9 is raised by the pressure of the spray air, and the inlet of the tubular portion 6 is opened. When pilot air is supplied, the piston 9 is lowered by the pressure, the inlet of the tubular portion 6 is closed, and the spray liquid is shut off. The coil spring 10 is provided to balance the pressure of the spray air.
[00 37 ]
As shown in FIGS. 4 and 5, the nozzle tip 7 has a distal end portion 12 in which a distal end of a tubular body portion 11 is formed in a dome shape, and a discharge port 8 having a horizontally long slit shape is formed in the body portion 11. It is open.
[00 38 ]
【The invention's effect】
In the coating method of the present invention, the first coating agent imparts lubricity and scratch resistance to the glass container, and the second coating agent imparts easy peeling performance. Since it suffices to perform only on the part (usually the body part) to which the label is applied, the coating unevenness of the coating agent is reduced, the probability that the desired easy peeling performance can be realized is increased, and the yield is improved. Moreover, the adjustment for realizing the desired easy peelability is simplified.
[00 39 ]
Since the glass container of the present invention has a desired easy peelability, the label does not peel off during use, and the label can be easily peeled off after use, contributing to glass recycling. In particular, if the coating film of the second coating agent is thick at the center in the vertical direction of the label affixing part and thinly formed at the upper and lower ends, the label is difficult to peel off during use and can be easily peeled off when the label is peeled off after use. Can do.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of coating by a spray nozzle 13;
FIG. 2 is an explanatory diagram of coating by a spray nozzle 1;
FIG. 3 is an explanatory diagram of a glass container G of the present invention.
FIG. 4 is a cross-sectional explanatory view of the spray nozzle 1 of the present invention.
FIG. 5 is a side view of the nozzle tip 7;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Spray nozzle 2 Liquid inlet 3 Gas inlet 4 Pilot air inlet 5 Mixing chamber 6 Tubular part 7 Nozzle tip 8 Discharge port 9 Piston 10 Coil spring 11 Trunk part 12 Tip part 13 Spray nozzle 20 Coating of 1st coating agent Coating 21 Coating film of second coating agent 22 Label

Claims (8)

A step of applying a first coating agent containing a solid lubricant to the outer surface of the glass container near the outlet of the slow cooling furnace in the manufacturing process of the glass container, and an ability to easily remove the label adhered to the outer surface of the glass container a second coating agent containing a silane coupling agent is a release substance 0.01 to 1 mass%, and having a step of coating the fabric sideways towards the body of the glass container with a spray nozzle Glass container coating method In the coating method of claim 1, wherein the second coating agent, a coating method for a glass container, which comprises 0.1～1Mass% silicone as the easy peeling substance 3. The coating method according to claim 1, wherein the second coating agent contains a solid lubricant. The coating method according to any one of claims 1 to 3 , wherein the solid lubricant of the first or second coating agent is polyethylene, polyethylene wax, modified polyethylene wax or carnauba wax. In any of the coating method according to claim 1-4, said concentration 0.01～10Mass% solids lubricant first coating agent, the concentration of the solid lubricant of the second coating agent is 0～2Mass% Method for coating glass container characterized by In any of the coating method according to claim 1 to 5, wherein the second step of applying a coating agent, supply respectively gas and liquid from the gas inlet and the liquid inlet formed in the nozzle body, the nozzle body A two-fluid nozzle that mixes in a mixing chamber and sprays a mist mixed with gas and liquid from a discharge port, and hangs an elongated tubular portion downward from the mixing chamber and laterally extends at the lower end of the tubular portion. A glass container coating method characterized by being performed by a spray nozzle provided with a nozzle tip having a slit-shaped discharge port   A glass container comprising a coating film formed on the outer surface by the coating method according to claim 1. In the glass container according to claim 7 , in the step of applying the second coating agent, the second coating agent is thickly applied to the center in the vertical direction of the label attaching portion of the glass container, and thinly applied to the upper and lower ends. A glass container characterized in that the coating film of the second coating agent is formed thick at the center in the vertical direction of the label attaching part and thin at the upper and lower ends.

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