Patent Application
20250033825
An embodiment of the present invention relates to a squeeze container.
Conventionally, a container allowing pushing of contents (examples: pharmaceuticals, quasi-pharmaceuticals, cosmetics) such as a liquid or cream contained in the container by pressing a flexible container from the outside is known as a squeeze container and is widely used.
When the contents accommodated in the squeeze container come into contact with oxygen in the air, desired characteristics of the contents may be impaired due to deterioration, for example, and a barrier layer such as an oxygen barrier layer may be formed in the squeeze container in order to curb such deterioration, for example, of the contents.
As a container in which such a barrier layer is formed, for example, a barrier tube container described in Patent Literature 1 (i.e., JP H11-321895 A) is known.
However, the conventional squeeze container in which the barrier layer is formed has room for improvement in terms of oxygen barrier properties, and also has room for improvement in terms of adhesion between the squeeze container main body as a base material and the barrier layer.
An embodiment of the present invention provides a squeeze container having an oxygen barrier layer having excellent adhesion to a squeeze container main body and excellent oxygen barrier properties.
As a result of intensive studies, the present inventors have completed the present invention according to the following configuration examples.
The configuration examples of the present invention are as follows.
[1] A squeeze container having an oxygen barrier layer formed from an active energy ray curable composition containing an alicyclic epoxy compound represented by Formula (1) below.
[R is an alkylene group having 1 to 4 carbon atoms, and R1 to R18 are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.]
[2] The squeeze container according to [1], in which the active energy ray curable composition contains a softness imparting agent.
[3] The squeeze container according to [2], in which the softness imparting agent is polycaprolactone triol.
[4] The squeeze container according to [2] or [3], in which a molecular weight of the softness imparting agent is 1000 or less.
[5] The squeeze container according to any one of [2] to [4], in which a content of the softness imparting agent is 7 to 20 mass % with respect to 100 mass % of a nonvolatile content of the active energy ray curable composition.
[6] The squeeze container according to any one of [1] to [5], in which a thickness of the oxygen barrier layer is 5 to 10 μm.
According to an embodiment of the present invention, it is possible to provide a squeeze container having an oxygen barrier layer excellent in adhesion with a squeeze container main body and having an excellent oxygen barrier property.
A squeeze container (hereinafter, also referred to as the “present container”) according to an embodiment of the present invention has an oxygen barrier layer formed from an active energy ray curable composition containing an alicyclic epoxy compound represented by Formula (1) below, and specifically has a squeeze container main body (squeeze container before an oxygen barrier layer is formed) and the oxygen barrier layer formed on the outer side thereof.
The present container only needs to include the squeeze container main body and the oxygen barrier layer, but may include conventionally known layers as necessary.
Examples of the conventionally known layer include a printed layer (for example, a digital ink layer) for displaying contents, design purposes, for example. The printed layer is usually formed on at least a part of the oxygen barrier layer (a side of the oxygen barrier layer opposite to the squeeze container main body).
Incidentally, a conventionally known layer, for example, an adhesive layer or others may be present between the squeeze container main body and the oxygen barrier layer, but according to an embodiment of the present invention, since the present container in which the squeeze container main body and the oxygen barrier layer are sufficiently in close contact can be obtained even without such a layer, it is preferable that such a layer do not exist in consideration of manufacturing costs, ease of manufacturing, for example, of the present container.
The application of the present container is not particularly limited, and examples thereof include applications such as using, storing, transporting, or others of: pharmaceutical products; quasi-pharmaceutical products; cosmetics; food; materials for construction, civil engineering, or agriculture; and others in a liquid, cream, or other state. Applications of using, storing, transporting, or others of liquid foundations, creams, facial foams, or others are more preferable.
The oxygen barrier layer is not particularly limited as long as it is a layer formed of an active energy ray curable composition containing an alicyclic epoxy compound represented by Formula (1) below.
The oxygen barrier layer may be formed in two or more layers on the squeeze container main body, but the oxygen barrier layer formed on the squeeze container main body is preferably one layer in consideration of the adhesion between the squeeze container main body and the oxygen barrier layer and the squeeze properties of the present container in the present container to be obtained.
The thickness of the oxygen barrier layer is preferably 5 to 10 μm from the viewpoint of sufficiently preventing permeation of oxygen for example, and is more preferably 5 to 7 μm from the viewpoint of easily obtaining the present container excellent in a balance between an oxygen barrier property and a squeeze property, for example.
The thickness of the oxygen barrier layer formed on the squeeze container main body is usually substantially uniform, but the thickness of the oxygen barrier layer may change according to the place where the oxygen barrier layer is formed as necessary.
The oxygen barrier layer may be formed only on at
least a part of the squeeze container main body, and may be formed only on a portion of the squeeze container main body required to suppress permeation of oxygen, but is usually formed on the entire surface of the squeeze container main body (the entire surface of a body part of the following squeeze container main body or the entire surface other than a mouth part of the following squeeze container main body).
The active energy ray curable composition (hereinafter, also referred to as the “present composition”) is not particularly limited as long as it contains an alicyclic epoxy compound represented by Formula (1) below. Since the present composition is of an active energy ray curing type composition, an oxygen barrier layer can be easily formed even when a squeeze container main body inferior in heat resistance is used as the squeeze container main body.
The present composition is preferably a cationically polymerizable active energy ray curable composition, and is preferably a solventless active energy ray curable composition from the viewpoint that the effects of the present invention are better exhibited, and an oxygen barrier layer having desired physical properties can be easily formed on the squeeze container main body, for example. In addition, by using the cationically polymerizable active energy ray curable composition, even if the printed layer (particularly, the digital ink layer) is formed on the oxygen barrier layer to be formed, it is possible to curb the components that form the printed layer migrating to the squeeze container main body, and further, the components passing through the squeeze container main body and migrating to the inner surface of the squeeze container main body (migration).
The present composition contains an alicyclic epoxy compound represented by Formula (1) below.
The alicyclic epoxy compounds contained in the present composition may be of one kind or two or more kinds.
[R is an alkylene group having 1 to 4 carbon atoms, and R1 to R18 are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.]
Examples of R include a methanediyl group, a 1,2-ethanediyl group, a 1,3-propanediyl group, a 1,4-butanediyl group, a 1,1-ethanediyl group, a 2,2-propanediyl group, a 1,2-propanediyl group, and a 1,1-dimethyl-1,2-ethanediyl group. Among these groups, a methanediyl group and a 1,2-ethanediyl group are preferable, and a methanediyl group is more preferable.
R1 to R18 each independently include, for example, a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group, an i-propyl group, and a t-butyl group, and among these groups, a hydrogen atom and a methyl group are preferable, and a hydrogen atom is more preferable.
As the alicyclic epoxy compound represented by Formula (1) above, a compound obtained by synthesis by a conventionally known method may be used, or a commercially available product may be used.
In a case where the present composition does not contain the following softness imparting agent, the content of the alicyclic epoxy compound represented by Formula (1) above in the present composition is preferably 98 to 99.5 mass % with respect to 100 mass % of the nonvolatile content of the present composition from the viewpoint of, for example, easily obtaining an oxygen barrier layer which is excellent in oxygen barrier properties and adhesion to a squeeze container main body and in which hardly any cracks are generated.
In a case where the present composition contains the following other components, particularly the following softness imparting agent, the content of the alicyclic epoxy compound represented by Formula (1) above in the present composition is preferably 79.5 to 92.5 mass % with respect to 100 mass % of the nonvolatile content of the present composition from the viewpoint of, for example, easily obtaining the present container excellent in balance among oxygen barrier properties, adhesion to a squeeze container main body, and squeeze properties.
The nonvolatile content of the present composition refers to components other than the solvent and dispersion medium in the present composition.
The present composition may contain other components other than the alicyclic epoxy compound represented by Formula (1) above as necessary as long as the effects of the present invention are not impaired.
Examples of the other component include an active energy ray curable compound other than the alicyclic epoxy compound represented by Formula (1) above, a softness imparting agent (plasticizer), a polymerization initiator, an antioxidant, an ultraviolet absorber, a surfactant, an antistatic agent, a flame retardant, a lubricant, a pigment (an extender pigment, a coloring pigment, for example), a dye, a silane coupling agent, a sensitizer, an antifoaming agent, a thickener, a leveling agent, a polymerization inhibitor, an antiseptic/antifungal agent, a pH adjusting agent, and a solvent/dispersion medium.
One kind of these other components may be independently used, or two or more kinds thereof may be used.
The total content of these other components is preferably 50 mass % or less with respect to 100 mass % of the nonvolatile content of the present composition.
It is preferable that the present composition particularly contains a softness imparting agent among the other components.
When the present composition contains such a softness imparting agent, the present container having excellent squeezability can be easily obtained.
The softness imparting agent is preferably a compound having an ester bond (—COO—), and examples thereof include acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, and glyceryl triacetate; phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, bis(2-ethylhexyl) phthalate, diisodecyl phthalate, butylbenzyl phthalate, diisononyl phthalate, ethyl phthalylethyl glycolate, isodecyl phthalate, diundecyl phthalate, and diisoundecylphthalate; aliphatic monobasic acid esters such as butyl oleate; aliphatic dibasic acid esters such as dimethyl adipate, dibutyl adipate, diisobutyl adipate, bis(2-ethylhexyl) adipate, diisononyl adipate, diisodecyl adipate, bis(2-(2-butoxyethoxy)ethyl) adipate, bis(2-ethylhexyl) azelate, dimethyl sebacate, dibutyl sebacate, bis(2-ethylhexyl) sebacate, diethyl succinate, dioctyl adipate, and isodecyl succinate; glycol esters such as diethylene glycol dibenzoate and pentaerythritol ester; trimellitic acid esters such as tris(2-ethylhexyl) trimellitate; ricinoleic acid esters such as methyl acetyl ricinoleate; pyromellitic acid esters; polyesters obtained by reacting dibasic acids and dihydric alcohols; poly (meth) acrylic acid esters such as poly (meth) acrylic acid alkyl esters; polyester polyols such as polycaprolactone triol and polycaprolactone diol; acetylated monoglycerides such as glycerin diacetomonolaurate; and epoxies such as epoxidized soybean oil, epoxidized linseed oil, and benzyl epoxy stearate.
Among them, polyester polyols are preferable, and polycaprolactone triol is more preferable from the viewpoint of, for example, easily obtaining the present container excellent in balance among oxygen barrier properties, adhesion to the squeeze container main body, and squeeze properties.
The molecular weight of the softness imparting agent is preferably 1000 or less, more preferably 850 or less, and still more preferably 550 or less from the viewpoint of, for example, easily obtaining a solventless composition excellent in coatability to the squeeze container main body and easily obtaining the present container excellent in balance among oxygen barrier property, adhesion to the squeeze container main body, and squeeze property, and the lower limit thereof is not particularly limited but is, for example, 300.
In a case where the present composition contains a softness imparting agent, the content of the softness imparting agent is preferably 7 to 20 mass % and more preferably 9 to 15 mass % with respect to 100 mass % of the nonvolatile content of the present composition from the viewpoint of, for example, easily obtaining the present container excellent in balance among oxygen barrier properties, adhesion to a squeeze container main body, and squeeze properties.
The squeeze container main body is not particularly limited as long as it is a container having flexibility and capable of pushing out the stored object in the container by pressing from the outside.
The shape of the squeeze container main body is not particularly limited, and may be the shape of a conventionally known squeeze container, and examples thereof include a squeeze container including a head portion including a mouth part 1, and a shoulder part 3 and a body part 2 (a portion to be squeezed when the present container is squeezed) connected to the mouth part 1 as illustrated in
A preferred example of the shape of the squeeze container main body is a tube container.
The squeeze container main body is preferably a squeeze container main body made of a thermoplastic resin containing a thermoplastic resin.
The thermoplastic resin preferably contains polyethylene, and more preferably contains low-density polyethylene. That is, the squeeze container main body is preferably a squeeze container main body made of polyethylene, and more preferably a squeeze container main body made of low density polyethylene.
The polyethylene may be a biomass-derived resin or a fossil fuel-derived resin, and is preferably an injection-moldable resin.
The thermoplastic resin contained in the squeeze container main body may be one kind alone or two or more kinds.
The squeeze container main body may contain additives such as stabilizers such as an antioxidant, a heat resistant stabilizer, a light resistant stabilizer, and a weather resistant stabilizer, an ultraviolet scattering agent, a slip inhibitor, an antifogging agent, a colorant, a dispersant, a filler, an antistatic agent, a lubricant, a softener, a plasticizer, and a processing aid as long as the effects of the present invention are not impaired, as necessary.
The squeeze container main body may contain one of these additives alone, or may contain two or more of these additives.
The squeeze container main body is not particularly limited, but is preferably an injection-molded squeeze container main body formed by injection molding from the viewpoint that a desirably shaped container main body can be easily formed, for example.
In a case where the squeeze container main body is a squeeze container main body as illustrated in
The thickness of the body part of the squeeze container main body may be appropriately selected according to a desired application, but is preferably 1.0 mm or less, more preferably 0.5 to 1.0 mm, and still more preferably 0.5 to 0.9 mm from the viewpoint that the present container can be easily squeezed when the present container is used by squeezing so as to extrude the contents, and that the present container with excellent flexibility can be easily obtained, for example.
The squeeze container main body containing a polyethylene is preferable because the squeeze container main body is easy to make an injection-molded squeeze container main body whose body part has such a thickness, and further becomes an injection-molded squeeze container main body excellent in injection moldability, flexibility, and stress cracking resistance, even when the body part has such a thickness.
The length of the body part of the squeeze container main body may be appropriately selected according to a desired application, and is preferably 10 cm or more, and more preferably 10 to 20 cm.
The squeeze container main body containing a polyethylene is preferable because the squeeze container main body is easy to make an injection-molded squeeze container main body whose body part has such a length, and further becomes an injection-molded squeeze container main body excellent in injection moldability, flexibility, and stress cracking resistance, even when the body part has such a length.
For example, the present container can be manufactured by providing the present composition on a squeeze container main body and irradiating the present composition with an active energy ray to cure the present composition.
Examples of the method of providing the present composition on the squeeze container main body include a method of applying the present composition on the squeeze container main body by a known coating method such as a roll coater, a curtain coater, or various types of printing, and a method of providing the present composition on the squeeze container main body by immersing the squeeze container main body in the present composition.
Alternatively, the present composition may be applied onto a support to form a film, and then the film may be transferred onto the squeeze container main body.
Before the present composition is provided on the squeeze container main body, the squeeze container main body may be subjected to a treatment such as a corona discharge treatment, a flame treatment, an ultraviolet treatment, a high frequency treatment, a glow discharge treatment, an active plasma treatment, or a laser treatment.
Examples of the active energy rays include light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, and infrared rays; electromagnetic waves such as X-rays and y rays; electron beams, proton beams, neutron beams, for example. Among these, ultraviolet rays and/or electron beams are preferred because they cause less damage to the squeeze container main body, for example.
The irradiation time depends on the intensity of light, the thickness of the oxygen barrier layer to be formed, and the present composition to be used, but is usually about 0.1 seconds to 10 seconds.
When the present composition is cured, heating may be performed as necessary in order to promote polymerization.
Hereinafter, an embodiment of the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto.
A surface (outer surface) of a container (injection molded container in which head and body are integrally molded, having a shape illustrated in
A 3′,4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate was applied to the corona discharge treated surface of the obtained squeeze container main body using a roll coater such that the thickness of the resulting oxygen barrier layer was 7 μm, and ultraviolet rays were irradiated using a UV exposure machine (metal halide lamp) such that the integrated amount of light was 531 mJ/cm2 (intensity: 1710 mW/cm2, irradiation distance: 65 mm, number of revolutions: 50 rpm, irradiation power: 120 W, irradiation time: 3 seconds), thereby preparing a squeeze container having an oxygen barrier layer.
A squeeze container having an oxygen barrier layer was prepared in the same manner as in Example 1 except that a composition obtained by mixing 100 parts by mass of 3′,4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and 14 parts by mass of polycaprolactone triol (molecular weight: 300) in advance was used instead of 3′,4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate in Example 1.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 2 except that polycaprolactone triol (molecular weight: 550) was used instead of polycaprolactone triol (molecular weight: 300) in Example 2.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 2 except that polycaprolactone triol (molecular weight: 850) was used instead of polycaprolactone triol (molecular weight: 300) in
Example 2.
A squeeze container having an oxygen barrier layer was prepared in the same manner as in Example 2 except that the oxygen barrier layer was formed such that the thickness of the oxygen barrier layer was 5 μm in Example 2.
A squeeze container having an oxygen barrier layer was prepared in the same manner as in Example 2 except that the oxygen barrier layer was formed such that the thickness of the oxygen barrier layer was 10 μm in Example 2.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 2 except that the use amount of polycaprolactone triol (molecular weight: 300) was changed to 11 parts by mass in Example 2.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 2 except that the use amount of polycaprolactone triol (molecular weight: 300) was changed to 17 parts by mass in Example 2.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 2 except that dibutyl phthalate (molecular weight: 278) was used in place of polycaprolactone triol (molecular weight: 300) in Example 2.
The squeeze container main body before corona discharge treatment (squeeze container having no oxygen barrier layer) used in Example 1 was used as it was.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 1 except that urethane acrylate (Forseed No. 300 M [manufactured by CHUGOKU MARINE PAINTS, LTD.]) was used instead of 3′,4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate in Example 1.
A squeeze container having an oxygen barrier layer was produced in the same manner as in Example 1 except that EVOH containing an inorganic layered filler (Ecostage GB [manufactured by SAKATA INX CORPORATION]) was used instead of 3′,4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate in Example 1.
The oxygen barrier property (oxygen cut ratio) of the squeeze container having the oxygen barrier layer produced in each of examples and comparative examples was measured as follows.
In a glove box filled with nitrogen, a mouth part and a hem portion (an end portion of the body part 2 in
This squeeze container was stored in a thermo-hygrostat at 23° C. and 50% RH, and thereafter, for the squeeze container of Comparative Example 1, the squeeze container was taken out from the thermo-hygrostat four times every two days, and for the squeeze containers having an oxygen barrier layer produced in examples and comparative examples other than Comparative Example 1, the squeeze container was taken out from the thermo-hygrostat four times every one week, the oxygen concentration inside each of the squeeze containers was measured by gas chromatography (Clarus 680 manufactured by PerkinElmer Inc.), and the oxygen cut ratio was calculated from the following formula. The results are shown in Table 1. The oxygen cut ratio described in Table 1 is an average value of oxygen cut ratios measured using six squeeze containers each having an oxygen barrier layer produced in each of examples and comparative examples.
Oxygen concentration [%]=02 peak area×k/(N2 peak area+O2 peak area×k)×100
k=(21.0×peak area of N2 in air)/(78.1×peak area of O02 in air)
Oxygen volume [cm3] in squeeze container=Oxygen concentration [%]×10−2×Volume [cm3] of squeeze container
Oxygen permeability [cm3/day/package]=slope of approximate curve of transition plot of oxygen volume in squeeze container
Oxygen cut ratio [%]={1-(Oxygen permeability of squeeze container having oxygen barrier layer/Oxygen permeability of squeeze container used in Comparative Example 1)}×100
The cross cut test was performed as follows based on the adhesiveness (cross cut method) of JIS K 5600 May 6: 1999.
Using the squeeze container having the oxygen barrier layer produced in each of examples and comparative examples, foreign matters such as dust, dust, and oil on the oxygen barrier layer on the squeeze container were removed, and 11 longitudinal and lateral cuts each having a depth reaching the squeeze container main bodies were placed at 1 mm intervals in the portion thus removed. A cellophane tape having a width of 15 mm (manufactured by Nichiban Co., Ltd.) was press-bonded to the cut surface, and then the cellophane tape was rapidly peeled off at an angle of about 60° with respect to the oxygen barrier layer surface by holding the end of the cellophane tape. The residual area ratio (%), which is the area of the oxygen barrier layer remaining on the squeeze container in the formed 100 squares, was calculated. The squeeze container having the oxygen barrier layer produced in each of examples and comparative examples was tested using 10 specimens, the average value of the residual area ratio was calculated, and the adhesiveness was evaluated according to the following criteria. The results are shown in Table 1.
10 points: The edge of the cut is completely smooth, and there is no peeling in any grid.
8 points: There is small peeling of the oxygen barrier layer at the intersection of the cuts, and the residual area ratio is 95% or more.
6 points: The oxygen barrier layer was peeled off along the edge of the cut and/or at the intersection, and the residual area ratio was 85% or more and less than 95%.
4 points: The oxygen barrier layer was partially or entirely peeled off along the edge of the cut, and the residual area ratio was 65% or more and less than 85%.
2 points: The oxygen barrier layer was partially or entirely peeled off along the edge of the cut, and the residual area ratio was 35% or more and less than 65%.
0 points: The oxygen barrier layer was partially or entirely peeled off along the edge of the cut, and the residual area ratio was less than 35%.
Using the squeeze container having the oxygen barrier layer produced in each of examples and comparative examples, when the finger was rotated 45° while the oxygen barrier layer immediately after being irradiated with ultraviolet rays was pressed with the finger for 2 to 3 seconds, the case where the oxygen barrier layer was not stuck to the finger was evaluated as 0, and the case where the oxygen barrier layer was stuck to the finger was evaluated as X. The results are shown in Table 1.
A printed layer was printed on the oxygen barrier layer by inkjet printing using the squeeze container having the oxygen barrier layer produced in each of examples and comparative examples. The squeeze container on which the printed layer was printed was wrung out and kept for 10seconds, and then the surface of the printed layer after releasing the force at the time of wring out was observed using a microscope, and the squeeze property was evaluated according to the following evaluation criteria. The results are shown in Table 1.
10 points: There is no peeling of the printed layer.
8 points: There is fine point peeling of several millimeters and/or linear peeling, and the area of the peeled portion of the printed layer when photographed with a microscope (magnification: 10 times) is less than 15% of the photographed area.
6 points: The area of the peeled portion of the printed layer when photographed with a microscope (magnification: 10 times) is 15% or more and less than 35% of the photographed area.
4 points: The area of the peeled portion of the printed layer when photographed with a microscope (magnification: 10 times) is 35% or more and less than 65% of the photographed area.
2 points: The area of the peeled portion of the printed layer when photographed with a microscope (magnification: 10 times) is 65% or more of the photographed area.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-196937 | Dec 2021 | JP | national |
This application is the United States national phase of International Patent Application No. PCT/JP2022/042250 filed Nov. 14, 2022, and claims priority to Japanese Patent Application No. 2021-196937 filed Dec. 3, 2021, the disclosures of which are hereby incorporated by reference in their entireties.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/042250 | 11/14/2022 | WO |
