Nucleated polypropylene resin for primary lens packages

Abstract

To provide packaging. [Solution] A primary package for holding contact lenses is disclosed. It is mainly made from a nucleated polypropylene resin. The nucleated polypropylene resin is determined to be formulated using a polypropylene-based resin having primary and secondary stabilizers, which also contains more than 99% polypropylene homopolymer and a catalytic acid scavenger, at least one nucleating agent / clearing agent, and at least one catalytic acid scavenger.

Description

Background Art

[0001] The present invention relates to a nucleated polypropylene formulation developed for use as a primary package for storing contact lenses.

[0002] It is desirable for the "primary" package, i.e., the package that holds the contact lens, to have several significant properties. First, it must be easy to manufacture and store. Second, it needs to have optical transparency, i.e., the wearer of the lens should be able to easily see the lens when it is held within the package. Third, it needs to be relatively impermeable in order to absorb the solution in which the lens is held. This allows the lens to be maintained in the correct chemical solution. This is useful when the lens and solution hold a drug for use in the eye. Then, as long as the package is relatively impermeable, the user can be confident that an appropriate amount of solution continues to be contained within the lens itself.

Summary of the Invention

Means for Solving the Problems

[0003] A novel primary package for holding contact lenses is disclosed. It is mainly made from a nucleated polypropylene resin. The nucleated polypropylene resin should be formulated using a polypropylene-based resin consisting of more than 99% polypropylene homopolymer containing primary and secondary stabilizers including an acid scavenger, and at least one nucleating agent / clarifying agent.

[0004] Specific inherent attributes are evident in the package created by its unique formulation. Firstly, the formulation has controlled shrinkage, designed to match the shrinkage of nucleate-free polypropylene in both cross-flow and in-flow directions. Throughout this, the polypropylene resin should maintain a high crystallization temperature. A particularly difficult aspect of nucleate-free materials is a lower crystallization temperature, which results in longer injection molding cycle times and lower mechanical productivity. Consequently, a high crystallization temperature allows for shorter cooling cycles in the injection molding process, and therefore, a reduction in the overall injection molding cycle time.

[0005] Secondly, the above resin formulation should result in a harder portion and improved optical clarity compared to parts made from nucleate-free resin. The benefits of optical clarity for packaging are rather obvious.

[0006] Thirdly, the material should benefit from a low transfer rate of additives from polypropylene to the packaging solution, resulting in reduced leaching of any plastic components into the packaging solution and contact lenses, which is, of course, a fairly important requirement for primary lens packaging.

[0007] In one embodiment of the present invention, the concentrations of the components are as follows: a) Base polypropylene resin ≥ 99% b) Acid scavenger <0.25% c) Nucleating agent / clearing agent <0.1%

[0008] One specifically useful base resin has been found to be 1-propene homopolymer. A useful scavenger is aluminum magnesium hydroxide carbonate hydrate, in an amount of about 0.04% by weight. The clarifying agent or nucleating agent was selected as 1,2-cyclohexanedicarboxylic acid, calcium salt (1:1), (1R,2S)-rel-, in an amount of about 0.05% by weight.

[0009] Several nucleating additives were evaluated, and in one embodiment, a calcium salt compound was used. In a concentration range of 0.02–0.10 wt% of the nucleating agent (calcium salt), the resin formulation exhibited a crystallization temperature in the range of 125°C–135°C, which is an ideal range for injection molding processes with relatively fast cycles of generally less than 3 seconds.

[0010] Antioxidants (also called stabilizers) may be included in the formulation to prevent resin degradation over time. Of the antioxidants or stabilizers analyzed, two specifically useful antioxidants were tris(3,5-di-butyl-4-hydroxybenzyl(hydroxylbenzyl)) isocyanurate as a primary antioxidant in an amount of approximately 0.05% by weight, and tris-(2,4-di-t-butylphenyl) phosphite as a secondary antioxidant in an amount of approximately 0.10% by weight. [Brief explanation of the drawing]

[0011] [Figure 1] This is a diagram of a package made using the formulation of the present invention. [Figure 2] This graph shows the rheological properties of the formulation used in the present invention. [Modes for carrying out the invention]

[0012] Figure 1 illustrates a typical contact lens package 100 fabricated using the present invention. It includes a "valve" or base 50 that holds a lens (not shown) in a solution. A film or cover 10 is placed over the lens in the solution.

[0013] The term “base” refers to any receptacle for a medical device, the size and shape of the base being determined by the device and other considerations known to those skilled in the art who manufacture or design molded bases. For example, a molded base may be an individual blister package, including a contact lens blister package, a secondary package, or a hydration tray. The molded base 50 may be prepared from any number of materials, provided that the number of materials is compatible with the chemical and physical properties of the device. With regard to the shape of the molded base, examples of suitably molded bases are disclosed in the following patents, which are incorporated herein by reference in their entirety. U.S. Patent Nos. D458,023, 4,691,820, 5,054,610, 5,337,888, 5,375,698, 5,409,104, 5,467,868, 5,515,964, 5,609,246, 5,695,049, and 5,69 Nos. 7,495, 5,704,468, 5,711,416, 5,722,536, 5,573,108, 5,823,327, 5,704,468, 5,983,608, 6,029,808, 6,044,966, and 6,401,915.

[0014] Similar to the cited references, the molded base 50 is sealed around the cavity surrounding the contact lens. The flexible film cover sheet 10 may be made from an adhesive laminate of aluminum foil and polypropylene film, or any other extruded or co-extruded film, which can be sealed to the upper surface of the flange to form an airtight seal for the medical device and solution. Furthermore, the base may be formed by any of several known methods, including but not limited to injection molding, transfer molding, skin packaging, blow molding, co-injection molding, film extrusion, or film co-extrusion.

[0015] A "homopolymer" is a polymer made from a single monomer. Polypropylene homopolymers are polypropylene polymerized with only one monomer, but may also contain additives that do not form part of the polymer chain. The following are examples of suitable polypropylene homopolymer resin grades (Flint Hills Resources) evaluated for the manufacture of primary lens packages. P4C5N-046 (homopolymer) • 11T55V (Transparent homopolymer) P4C6B-134A (homopolymer) • P4C6S-193A (Transparent homopolymer) P4C6N-041 (homopolymer) P4C6Z-059 (homopolymer) P4C6Z-022 (homopolymer) • P4C6B-194 (nucleated homopolymer)

[0016] Preferred examples of alpha nucleating agents with a preferred configuration include the following: Sodium-2,2'-methylene-bis(4,6-di-t-butylphenyl)phosphate, Sodium-2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate, • Lithium-2,2'-methylene-bis(4,6-di-t-butylphenyl)phosphate, • Lithium-2,2'-ethylidene-bis(4,6-di-t-butylphenyl) phosphate, Sodium-2,2'-ethylidene-bis(4-1-propyl-6-t-butylphenyl)phosphate, • Lithium-2,2'-methylene-bis(4-methyl-6-t-butylphenyl) phosphate, • Lithium-2,2'-methylene-bis(4-ethyl-6-t-butylphenyl) phosphate, • Calcium-bis[2,2'-thiobis(4-methyl-6-t-butylphenyl)phosphate], · Calcium - bis[2,2’ - thiobis(4 - ethyl - 6 - t - butylphenyl)phosphate], · Calcium - bis[2,2’ - thiobis(4,6 - di - t - butylphenyl)phosphate], · Magnesium - bis[2,2’ - thiobis(4,6 - di - t - butylphenyl)phosphate], · Magnesium - bis[2,2’ - thiobis(4 - t - octylphenyl)phosphate], · Sodium - 2,2’ - butylidene - bis(4,6 - dimethylphenyl)phosphate, · Sodium - 2,2’ - butylidene - bis(4,6 - di - t - butylphenyl)phosphate, · Sodium - 2,2’ - t - octylmethylene - bis(4,6 - dimethylphenyl)phosphate, · Sodium - 2,2’ - t - octylmethylene - bis(4,6 - di - t - butylphenyl)phosphate, · Calcium - bis[2,2’ - methylene - bis(4,6 - di - t - butylphenyl)phosphate], · Magnesium - bis[2,2’ - methylene - bis(4,6 - di - t - butylphenyl)phosphate], · Barium - bis[2,2’ - methylene - bis(4,6 - di - t - butylphenyl)phosphate], · Sodium - 2,2’ - methylene - bis(4 - methyl - 6 - t - butylphenyl)phosphate, · Sodium - 2,2’ - methylene - bis(4 - ethyl - 6 - t - butylphenyl)phosphate, · Sodium(4,4’ - dimethyl - 5,6’ - di - t - butyl - 2,2’ - biphenyl)phosphate, · Calcium - bis[(4,4’ - dimethyl - 6,6’ - di - t - butyl - 2,2’ - biphenyl)phosphate], · Sodium - 2,2’ - ethylidene - bis(4 - m - butyl - 6 - t - butylphenyl)phosphate, · Sodium - 2,2’ - methylene - bis(4,6 - dimethylphenyl)phosphate, Sodium-2,2'-methylene-bis(4,6-diethylphenyl)phosphate, • Potassium-2,2'-ethylidene-bis(4,6-di-t-butylphenyl) phosphate, • Calcium-bis[2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], • Magnesium-bis[2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], Barium-bis[2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], • Aluminum-tris[2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], • Aluminum-hydroxy-bis[2,2'-methylene-bis(4,6-di-t-butyl-phenyl)phosphate].

[0017] Examples of phosphorus-based nucleating agents in the second group include aluminum-hydroxy-bis[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo-[d,g]-dioxa-phosphosine(phoshocin)-6-oxidato], and mixtures thereof with Li-myristate or Li-stearate.

[0018] Among phosphorus-based nucleating agents, sodium-2,2'-methylene-bis(4,6-di-t-butylphenyl)phosphate or aluminum-hydroxy-bis[2,2'-methylene-bis(4,6-di-t-butylphenyl)-phosphate] or aluminum-hydroxy-bis-[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo-[d,g]-dioxa-phosphosine-6-oxidato] or mixtures thereof with Li-myristate or Li-stearate are particularly preferred.

[0019] In addition, sorbitol-based nucleating agents such as optionally substituted dibenzylidine sorbitol (e.g., 1,3:2,4 dibenzylidene sorbitol, 1,3:2,4 di(methylbenzylidene) sorbitol, 1,3:2,4 di(ethylbenzylidene) sorbitol, 1,3:2,4 bis(3,4-dimethylbenzylidene) sorbitol, or pine rosin can also be used as nucleating agents. Further preferred alpha nucleating agents are polymer nucleating agents selected from the group consisting of vinylcycloalkane polymers and vinylalkane polymers. Nucleation by these polymer nucleating agents is achieved either by special reactor techniques that prepolymerize the catalyst with a monomer such as vinylcyclohexane (VCH), or by mixing a propylene polymer with a vinyl(cyclo)alkane polymer. These methods are described in detail, for example, by European Patent No. 0 316 187 A2 and International Publication No. 99 / 24479, whose disclosures are incorporated herein by reference.

[0020] ADK NA-11 (methylene-bis(4,6-di-t-butylphenyl) phosphate sodium salt) and ADK NA-21 (aluminum hydroxy-bis[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo-[d,g]-dioxa-phosphosine-6-oxidato]) are commercially available from Asahi Denka Kokai and are preferably added to the polyolefin compositions of the present invention. Millad 3988 (3,4-dimethylbenzylidenesorbitol), Millad NX8000, Millad 3905, and Millad 3940, available from Milliken & Company, are other examples of nucleating agents that can be used in the present invention.

[0021] Further commercially available alpha nucleating agents that can be used in the compositions of the present invention include, for example, Irgaclear XT 386 (N-[3,5-bis-(2,2-dimethyl-propionylamino)-phenyl]-2,2-dimethylpropionamide) from BASF (officially Ciba Speciality Chemicals), and Hyperform HPN-68L and Hyperform HPN-20E from Milliken & Company.

[0022] Among all of the above alpha nucleating agents, aluminum hydroxy-bis[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo-[d,g]-dioxa-phosphosine-6-oxidato]-based nucleating agents such as ADK NA-21, NA-21 E, and NA-21 F; sodium-2,2'-methylene-bis(4,6-di-t-butylphenyl) phosphate (ADK NA-11); aluminum-hydroxy-bis[2,2'-methylene-bis(4,6-di-t-butylphenyl)-phosphate]; sorbitol-based nucleating agents such as Millad 3988, Millad 3905, and Millad 3940; and polymer-based nucleating agents selected from the group consisting of vinylcycloalkane polymers and vinylalkane polymers are particularly preferred.

[0023] According to one embodiment of the present invention, at least one alpha nucleating agent is composed of a polymer nucleating agent selected from the group consisting of vinylcycloalkane polymers and vinylalkane polymers, preferably polyvinylcyclohexane (pVCH).

[0024] According to further embodiments, at least one alpha nucleating agent is selected from the group consisting of aluminum hydroxybis[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo-[d,g]-dioxa-phosphosine-6-oxato]-based nucleating agents (e.g., ADK NA-21, NA-21 E, NA-21 F), sodium 2,2'-methylene-bis(4,6-di-t-butylphenyl) phosphate (ADK NA-1 1), aluminum-hydroxy-bis[2,2'-methylene-bis(4,6-di-t-butylphenyl) phosphate] and sorbitol-based nucleating agents (e.g., Millad NX8000, Millad 3988, Millad 3905, and Millad 3940).

[0025] In embodiments, at least one alpha-nucleating agent is selected from the group and comprises vinylcycloalkane polymers and vinylalkane polymers, preferably polyvinylcyclohexane (pVCH).

[0026] The additives are preferably present in the polymer composition and may be partially or completely present when added to the polymer composition during preparation. The additives are suitably selected from the group consisting of primary antioxidants such as sterically hindered phenols and secondary antioxidants such as phosphates, UV stabilizers such as sterically hindered amines, acid scavengers, carbon black, pigments, antistatic agents such as glycerol monostearate, oleamides, plasticizers, anti-scratch agents, dispersants, processing aids, and lubricants.

[0027] The additives are commercially available and are described, for example, in Hans Zweifel's 2009 6th edition "Plastic Additives Handbook" (pages 1141-1190), and are typically used in conventional quantities. Those skilled in the art would likely be familiar with these products and have experience using them.

[0028] Package 100 is formed from a novel nucleated resin formulation developed to support the production of the primary package (base 50). The resin formulation was designed using polypropylene material and additive packaging. The key properties of the formulated resin are as follows: • Ability to perform faster injection molding cycle times, • Improvement of the feasibility of the manufacturing process, • Reduction of blister haze (improved transparency) • Partial shrinkage rate corresponding to at least that of nucleate-free resins, • Low elution (extractable) level, • The ability to manufacture using the current packaging molds. • The ability to shorten injection molding cycle time without adding expensive mold coolers to cool the mold.

[0029] Some embodiments were formulated using optional components that may include UV blockers, UV reflectors, and coloring dyes.

[0030] The nucleated polypropylene resin used to manufacture the lens primary package (blister 50) was formulated as follows: A polypropylene-based resin comprising more than 99% polypropylene homopolymer, containing primary and secondary stabilizers that also function as acid scavengers, • At least one nucleating agent / clearing agent.

[0031] In one particularly preferred embodiment, the concentrations of the components were as follows: ·Base polypropylene resin ≥ 99% • Acid scavenger <0.25% • Nucleating agent / clearing agent <0.1%

[0032] In the case of contact lens package 100, the compounded nucleated resin may have observed physical properties within the following specified ranges. • Melt flow rate range of 20-40 g / 10 min as measured in accordance with ASTM D 1238. • Density of approximately 0.90 g / cm³ as measured in accordance with ASTM D 1505. • Melting temperature range of 130°C to 165°C as measured in accordance with ASTM D 3418 • Deflection temperature in the range of 105°C to 120°C at at least 66 psi (.455 MPa) as measured in accordance with ASTM D 648. • Main heat of fusion (J / g) in the range of 90-105 when measured in accordance with ASTM D 34181.

[0033] Examples 1-4 The inventors manufactured plastic plaques and packages in a thickness range of 0.5 to 1.0 mm, which is a common range for contact lens packages. Typical injection molding parameters are shown in Table 1. It should be understood that the parameters may be modified depending on the size of the package and the desired properties, such as the need for robustness, length of use, and flexibility.

[0034] [Table 1]

[0035] Inflow and crossflow shrinkage of the test material were measured for each formulation, including material shrinkage, using conventional measurement techniques. Shrinkage rates were measured using a 4" x 4" plastic plate with a thickness of 1 / 8"". The size was measured at the completion of molding and again 40 hours later. The observed difference was the amount of shrinkage.

[0036] The nucleated polypropylene is selected using a base resin. One particularly useful base resin has been found to be 1-propene homopolymer. The base resin was used in each of the following embodiments, and their performance characteristics were tested accordingly.

[0037] [Table 2]

[0038] Subsequently, as shown in Table 3, the inventors compared the mechanical properties and injection molding properties of a specific nucleate-free resin along with three embodiments of the nucleating resin formulation.

[0039] [Table 3]

[0040] As shown in Table 4, the additive concentrations were optimized for the injection molding process and part shrinkage rate, and the shrinkage rate closely matched that of the nucleate-free material.

[0041] [Table 4]

[0042] The resin formulations described above produced the rheological profiles shown in the graph in Figure 2. In the graph, the nucleated resin is identified as the "high Tc blister material," and the non-nucleated resin is identified as the "standard material." The nucleated material exhibits high sensitivity to shear, assisting in filling and packing the mold cavity when fabricating parts. Higher shear and Tc allow for faster mold filling and cooling at lower pressures.

[0043] From these tests and experiments, the following conclusions can be drawn. • The nucleation package, combined with the selected polypropylene molecular weight distribution, results in a material with well-controlled shrinkage properties. • Core-containing resins have a shrinkage rate similar to that of core-free resins. Primary packages made from the core-containing polypropylene described above are advantageously comparable to packages made from core-free polypropylene. The primary package significantly reduces injection molding cycle time, allowing for faster manufacturing without affecting part dimensions. No modifications to the mold or mold cavity are required to produce the package using the cored resin. For example, using a Universal Pack 8 cavity mold with a Nestal E-Jet 500 injection molding machine, the introduction of a cored polypropylene resin grade (P4H6N-222) reduced the injection cycle from 2.70 seconds to 2.15 seconds. This reduced cycle time was maintained for many hours without any process problems. In other short tests using the same injection molding machine, a cycle time as short as 1.9 seconds was achieved. The process was accelerated simply by changing the polypropylene resin, without changing the injection molding machine. Considering its properties, the nucleated polypropylene formulations described herein enable on-demand part production. Normally, when using unnucleated polypropylene, the injection molding machine (IMM) remains operational even if lens production is temporarily suspended or stopped. During this time, blisters continue to be produced and discarded or recycled. This is because if an IMM operating with unnucleated polypropylene is subsequently stopped, production cannot be immediately resumed. The line must be purged and idled to achieve a stable production state. This process can take 15 minutes or more, but it is essential because failure to bring the IMM to a steady state will result in warped and substandard parts.

[0044] When using nucleated polypropylene, such limitations do not exist. Using such resin eliminates part warping, allowing for instantaneous stopping and starting of the IMM without issue. Furthermore, the primary package production speed can be accelerated or decelerated to meet the lens production requirements at any given time. This characteristic gives users the ability to create "on-demand production" of primary packages, addressing the reduction of polypropylene waste, especially in 24 / 7 production environments.

[0045] While the present invention is described for use in contact lenses, it should be understood that it is fully adaptable for use in any package using such nucleated polypropylene. For example, this technology is adaptable for use in any molded substrate. These and other objects of the present invention will be better understood from the appended claims and their equivalents.

[0046] [Implementation Method] (1) A package, A nucleated polypropylene resin formed from a polypropylene-based resin consisting of a polypropylene homopolymer, a primary stabilizer, and a secondary stabilizer, At least one nucleator, At least one catalytic acid scavenger, A package that includes this. (2) The package according to Embodiment 1, wherein the homopolymer is a 1-propene homopolymer. (3) The package according to Embodiment 1, wherein the scavenging agent is magnesium hydroxide carbonate hydrate. (4) The package according to Embodiment 1, wherein the nucleating agent is 1,2-cyclohexanedicarboxylic acid, calcium salt (1:1), (1R,2S)-rel-. (5) The package according to Embodiment 1, wherein the primary stabilizer is tris(3,5-di-butyl-4-hydroxybenzyl) isocyanurate.

[0047] (6) The package according to Embodiment 1, wherein the secondary stabilizer is tris-(2,4-di-t-butylphenyl) phosphite. (7) The package according to Embodiment 1, wherein the scavenging agent is present in an amount of about 0.04% by weight. (8) The package according to Embodiment 1, wherein the nucleating agent is present in an amount of about 0.04% by weight. (9) The package according to Embodiment 1, wherein the primary antioxidant is present in an amount of about 0.05% by weight. (10) The package according to Embodiment 1, wherein a secondary antioxidant is present in an amount of about 0.10% by weight.

[0048] (11) The package according to Embodiment 1, wherein the homopolymer is present in an amount exceeding 99% by weight. (12) Package, A nucleated polypropylene resin formed from a polypropylene-based resin containing more than 99% by weight, wherein the resin comprises a polypropylene homopolymer, a primary stabilizer, and a secondary stabilizer, At least one nucleating agent in less than 0.25% by weight, At least one catalytic acid scavenger in less than 0.1% by weight, A package that includes this. (13) A package for holding contact lenses, A nucleated polypropylene resin formed from a polypropylene-based resin consisting of a polypropylene homopolymer, a primary stabilizer, and a secondary stabilizer, At least one nucleating agent, At least one catalytic acid scavenger, A package that includes this.

Claims

1. A package formed from a resin compound, wherein the resin compound is A nucleated polypropylene resin formed from a polypropylene-based resin comprising a polypropylene homopolymer and a primary stabilizer and a secondary stabilizer, wherein the primary stabilizer is tris(3,5-di-butyl-4-hydroxybenzyl) isocyanurate, At least one nucleating agent comprising 1,2-cyclohexanedicarboxylic acid, calcium salt (1:1), (1R,2S)-rel-, At least one catalytic acid scavenger, wherein the at least one catalytic acid scavenger comprises magnesium aluminum hydroxide carbonate hydrate, Includes, The aforementioned resin compound exhibits a crystallization temperature in the range of 125°C to 135°C, and is a package.

2. The package according to claim 1, wherein the polypropylene homopolymer is 1-propene homopolymer.

3. The package according to claim 1, wherein the secondary stabilizer is tris-(2,4-di-t-butylphenyl) phosphite.

4. The package according to claim 1, wherein the at least one catalytic acid scavenger is present in an amount of about 0.04% by weight.

5. The package according to claim 1, wherein the at least one nucleating agent is present in an amount of about 0.04% by weight.

6. The package according to claim 1, wherein the primary stabilizer is present in an amount of about 0.05% by weight.

7. The package according to claim 1, wherein the secondary stabilizer is present in an amount of about 0.10% by weight.

8. The package according to claim 1, wherein the polypropylene homopolymer is present in an amount exceeding 99% by weight.

9. A package formed from a resin compound, wherein the resin compound is A nucleated polypropylene resin formed from a polypropylene-based resin comprising more than 99% by weight, wherein the polypropylene-based resin comprises a polypropylene homopolymer, a primary stabilizer, and a secondary stabilizer, wherein the primary stabilizer is tris(3,5-dibutyl-4-hydroxybenzyl) isocyanurate, A nucleating agent comprising less than 0.25% by weight of at least one nucleating agent, wherein the at least one nucleating agent comprises 1,2-cyclohexanedicarboxylic acid, calcium salt (1:1), (1R,2S)-rel-, A catalytic acid scavenger comprising less than 0.1% by weight of at least one catalytic acid scavenger, wherein the at least one catalytic acid scavenger comprises magnesium aluminum hydroxide carbonate hydrate, Includes, The aforementioned resin compound exhibits a crystallization temperature in the range of 125°C to 135°C, and is a package.

10. The package according to claim 9, wherein the secondary stabilizer is tris-(2,4-di-t-butylphenyl) phosphite.

11. The package according to claim 10, wherein the polypropylene homopolymer is 1-propene homopolymer.

12. A package for holding contact lenses, formed from a resin compound, the resin compound is A nucleated polypropylene resin formed from a polypropylene-based resin comprising a polypropylene homopolymer and a primary stabilizer and a secondary stabilizer, wherein the primary stabilizer is tris(3,5-di-butyl-4-hydroxybenzyl) isocyanurate, At least one nucleating agent comprising 1,2-cyclohexanedicarboxylic acid, calcium salt (1:1), (1R,2S)-rel-, At least one catalytic acid scavenger, wherein the at least one catalytic acid scavenger comprises magnesium aluminum hydroxide carbonate hydrate, Includes, The aforementioned resin compound exhibits a crystallization temperature in the range of 125°C to 135°C, and is a package.

13. The package according to claim 12, wherein the secondary stabilizer is tris-(2,4-di-t-butylphenyl) phosphite.

14. The primary stabilizer is present in the resin compound in an amount of approximately 0.05% by weight. The aforementioned secondary stabilizer is present in the resin compound in an amount of approximately 0.10% by weight. The at least one catalyst acid scavenger is present in the resin compound in an amount of about 0.03% by weight. The package according to claim 3, wherein the at least one nucleating agent is present in the resin compound in an amount of about 0.05% by weight.

15. The at least one catalyst acid scavenger is present in the resin compound in an amount of at least 0.04% by weight. The package according to claim 9, wherein the at least one nucleating agent is present in the resin formulation in an amount of at least 0.04% by weight.

16. The primary stabilizer is present in the resin compound in an amount of approximately 0.05% by weight. The aforementioned secondary stabilizer is present in the resin compound in an amount of approximately 0.10% by weight. The at least one catalyst acid scavenger is present in the resin compound in an amount of about 0.03% by weight. The package according to claim 13, wherein the at least one nucleating agent is present in the resin compound in an amount of about 0.05% by weight.

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