Compositions and articles comprising complexes of 1-methylcycloproprene and alpha-cyclodextrin

Abstract

Compositions comprising complexes of 1-methylcyclopropene and α-cyclodextrin, and articles including the composition, are provided. Methods for using the compositions and articles in delaying the maturation of fruits, vegetables, and plants are also provided.

Claims

1. An adhesive label comprising (a) a substrate having a first surface and a second surface; (b) a layer on the first surface consisting essentially of a hydrophilic composition, wherein the composition comprises: (i) a complex of 1-methylcyclopropene and a-cyclodextrin; and (ii) a polymer binder selected from the group consisting of polyvinylpyrrolidone and copolymers thereof, polyvinyl alcohol and copolymers thereof, polyvinyl acetate copolymers, and combinations thereof; (c) at least one additional functional layer covering the layer on the first surface; and (d) an adhesive provided on the second surface; wherein the hydrophilic composition is capable of releasing the 1-methylcyclopropene in the form of a gas when exposed to moisture, and wherein the at least one additional functional layer changes the 1-methylcyclopropene release profile relative to what the 1-methylcyclopropene release profile would be in the absence of the layer.

2. The adhesive label of claim 1, wherein the ratio of polymer binder to complex on a weight to weight basis is from about 2:1 to about 1:2.

3. The adhesive label of claim 1, wherein the polymer binder has a molecular weight ranging from about 5,000 to about 15,000.

4. The adhesive label of claim 1, wherein the polymer binder has a molecular weight of about 10,000.

5. The adhesive label of claim 1, wherein the hydrophilic composition further comprises a hygroscopic agent.

6. The adhesive label of claim 5, wherein the hygroscopic agent is selected from the group consisting of glycerol, glucose, and combinations thereof.

7. The adhesive label of claim 1, wherein the hydrophilic composition further comprises a humidity-indicating dye.

8. The adhesive label of claim 1, wherein the substrate comprises a paper substrate.

9. The adhesive label of claim 1, wherein the substrate comprises cardboard.

10. The adhesive label of claim 1, wherein the at least one additional functional layer comprises a barrier polymer, a hydrophilic material, a hydrophobic material, or a hygroscopic material.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1. is an exploded perspective view of a functional sticker with an active layer containing 1-MCP.

(2) FIG. 2 is a graph showing dependence of the concentration of isolated 1-MCP (mL/L) from a time (h) at a relative humidity of 85% and 100% for Example A-1.

(3) FIG. 3 is a graph showing dependence of the concentration of isolated 1-MCP (mL/L) from a time (h) in the moisture content of apple for Example A-1.

(4) FIG. 4 is a graph showing dependence of the concentration of isolated 1-MCP (μL/L) from a time (h) at a relative humidity of 100% at 6° C. for Example A-1.

(5) FIG. 5 is a graph showing dependence of the released 1-MCP concentration (mL/L) from time (h) at 85% and 100% relative humidity for Example A-2.

(6) FIG. 6 is a graph showing dependence of the concentration of isolated 1-MCP (μL/L) from a time (h) at a relative humidity of 100% at 6° C. for Example A-2.

(7) FIG. 7 is a graph showing dependence of the concentration of isolated 1-MCP (mL/L) from a time (h) at a relative humidity of 85% and 100% for Example 3.

(8) FIG. 8 is a graph showing dependence of the concentration of isolated 1-MCP (μL/L) from a time (h) at a relative humidity of 100% at 6° C. for Example A-3.

(9) FIG. 9 is a graph showing dependence of the concentration of isolated 1-MCP (mL/L) from a time (h) at a relative humidity of 85% and 100% for Example A-4.

(10) FIG. 10 is a graph showing dependence of the concentration of isolated 1-MCP (11L/L) from a time (h) at a relative humidity of 100% at 6° C. for Example A-4.

(11) FIG. 11 is a graph showing dependence of the concentration of isolated 1-MCP (mL/L) from a time (h) at a relative humidity of 85% and 100% for Example A-5.

(12) FIG. 12A is a chromatogram from which the concentration presented in FIG. 11 was determined.

(13) FIG. 12B is a chromatogram from which the concentration presented in FIG. 11 was determined.

(14) FIG. 13A is a chromatogram from which the concentration presented in FIG. 11 was determined.

(15) FIG. 13B is a chromatogram from which the concentration presented in FIG. 11 was determined.

(16) FIG. 14 is a graph showing dependence of 1-MCP isolated concentration (mL/L) from time (h) at 75% and 80% relative humidity for Example A-6.

(17) FIG. 15 is a graph showing dependence of the secreted concentration of 1-MCP (mL/L) from a time (h) at a relative humidity of 85% and 100% for Example A-7.

(18) FIG. 16 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 1 of Example A-8 at 85% relative humidity.

(19) FIG. 17 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 2 of Example A-8 at 85% relative humidity.

(20) FIG. 18 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 3 of Example A-8 at 85% relative humidity.

(21) FIG. 19 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 4 of Example A-8 at 85% relative humidity.

(22) FIG. 20 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 5 of Example A-8 at 85% relative humidity.

(23) FIG. 21 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 6 of Example A-8 at 85% relative humidity.

(24) FIG. 22 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 7 of Example A-8 at 85% relative humidity.

(25) FIG. 23 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 8 of Example A-8 at 85% relative humidity.

(26) FIG. 24 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for a 5 cm.sup.2 sample of Example A-8 at 85% relative humidity.

(27) FIG. 25 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for a 10 cm.sup.2 sample of Example A-8 at 85% relative humidity.

(28) FIG. 26 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for a 20 cm.sup.2 sample of Example A-8 at 85% relative humidity.

(29) FIG. 27 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for a 40 cm.sup.2 sample of Example A-8 at 85% relative humidity.

(30) FIG. 28 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for Sample A, a 100 cm.sup.2 sample, of Example A-8 at 85% relative humidity.

(31) FIG. 29 is a graph showing concentration of 1-MCP released over time per cm.sup.2 for Sample B, a 100 cm.sup.2 sample, of Example A-8 at 85% relative humidity.

(32) FIG. 30 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 1 of Example A-9 at 85% relative humidity.

(33) FIG. 31 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 2 of Example A-9 at 85% relative humidity.

(34) FIG. 32 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 1 of Example A-10 at 85% relative humidity.

(35) FIG. 33 is a graph showing concentration of 1-MCP released over time per cm.sup.2 of Sample 2 of Example A-10 at 85% relative humidity.

(36) FIG. 34 illustrates an example of a stick containing 1-MCP included in a dispenser for applying the contents of the stick.

(37) FIG. 35 is a chromatogram presented for the stick described in Example B-1. The 1-MCP retention time was 5.920 min. versus a retention time of 6.395 min. for the cis-2-butene reference standard.

(38) FIG. 36 is a chromatogram presented for the stick described in Example B-2. The 1-MCP retention time was 6.067 min. versus a retention time of 6.540 min. for the cis-2-butene reference standard.

(39) FIG. 37 is a graph showing the concentration of 1-MCP released over the time from the stick described in Example B-3.

(40) FIG. 38 is a graph showing the concentration of 1-MCP released over time from the stick described in Example B-4.

(41) FIG. 39 shows the construction of a functional film in ABA format, where ABA means the system: active layer A/carrier layer B/active layer A.

(42) FIG. 40 shows the chromatogram of air from a film sample made by head technique space.

(43) FIG. 41 shows the mass spectrum of 1-methylcyclopropene.

(44) FIG. 42 shows the mass spectrum of cis-2-butene.

(45) Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

(46) The invention will now be described further by way of the following examples.

A. Labels

Example 1

(47) Poly(vinylpyrrolidone) (MW=10,000) (25% by weight) was dissolved in 2-propanol (50% by weight) and the 1-methylcyclopropene/alpha-cyclodextrin complex (25% by weight) was added (the 1-MCP content in the complex was 3.3%). The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing each in gas-tight containers with sampling valves under conditions of defined humidity.

(48) 6.4 cm×4.6 cm labels were placed in a 900 ml glass vessel. A container with a saturated solution of the appropriate salt was placed in the vessel to obtain the correct relative humidity, or a sponge soaked in water was placed in the vessel instead of salt solution to obtain 100% relative humidity. 250 μL of cis-2-butene was introduced into the vessel with a gas-tight syringe.

(49) The concentration of 1-MCP was determined as compared to cis-2-butene as a reference, using a gas chromatograph equipped with a PoraBOND Q column: 25 m×0.25 mm internal diameter (i.d.)×3 μm and a flame ionization detector (FID). Cis-2-butene was used as a reference because it has the same response from an FID detector as 1-methylcyclopropene.

(50) For analysis, 250 μL gas was collected with a gas-tight syringe and injected into the above-mentioned column under the following conditions: temperature of the split/splitless injector 120° C.; isothermal 120° C., temperature of the FID 240° C. detector, split 20:1, carrier gas flow (helium) 50 cm/s.

Example 2

(51) Poly(vinylpyrrolidone) (MW=10,000) (40 wt %) was dissolved in 2-propanol (40 wt %) and the 1-methylcyclopropene/alpha-cyclodextrin complex (20 wt %) was added (the 1-MCP content in the complex was 3.3%). The resulting paste was applied to the self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(52) The concentration of 1-MCP was determined analogously to Example 1.

Example 3

(53) Poly(vinylpyrrolidone) (MW=10,000) (20 wt %) was dissolved in 2-propanol (40 wt %) and the 1-methylcyclopropene/alpha-cyclodextrin complex (40 wt %) was added (the 1-MCP content in the complex was 3.3%). The resulting paste was applied to the self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(54) The concentration of 1-MCP was determined analogously to Example 1.

Example 4

(55) Poly(vinylpyrrolidone) (MW=10,000) (45 wt %) was dissolved in 2-propanol (40 wt %) and the 1-methylcyclopropene/alpha-cyclodextrin complex (15 wt %) was added (the 1-MCP content in the complex was 3.3%). The resulting paste was applied to the self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(56) The concentration of 1-MCP was determined analogously to Example 1.

Example 5

(57) Poly (1-vinylpyrrolidone-co-vinyl acetate) (MW=13,000) (25% by weight) was dissolved in 2-propanol (50% by weight) and the 1-methylcyclopropene/alpha-cyclodextrin complex (25% by weight) was added (content 1-MCP in the complex was 3.3%). The resulting paste was applied to the self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(58) The concentration of 1-MCP was determined analogously to Example 1.

Example 6

(59) Poly(vinylpyrrolidone) (MW=10,000) (20 wt %) was dissolved in 2-propanol (40 wt %) and the 1-methylcyclopropene/alpha-cyclodextrin complex (20 wt %) was added (the 1-MCP content in the complex was 3.3%), and glycerine (20% by weight). The resulting paste was applied to the self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(60) The concentration of 1-MCP was determined analogously to Example 1.

Example 7

(61) Poly(vinylpyrrolidone) (MW=10,000) (20 wt %) was dissolved in 2-propanol (55 wt %) and the 1-methylcyclopropene/alpha-cyclodextrin complex (20 wt %) was added (the 1-MCP content in the complex was 3.3%), and glycerine (5% by weight). The resulting paste was applied to the self-adhesive paper using screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested by placing them in gas-tight containers with sampling valves under conditions of defined humidity.

(62) The concentration of 1-MCP was determined analogously to Example 1.

Example 8

(63) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %) and 1-methylcyclopropene/alpha-cyclodextrin complex (50 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste (for every 10 g of dry mixture, between 5 mL and 20 mL 2-propanol is used). The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, 6.4 cm×4.6 cm labels (29.44 cm.sup.2) were cut from the paper and tested for total amount of 1-MCP released and amount of 1-MCP released per cm.sup.2 of the label, under 100% relative humidity conditions or 85% relative humidity conditions.

(64) To test the samples under 100% relative humidity conditions, the samples were each placed in a 250 mL bottle and then 2 mL of distilled water was added. Next, the bottle was tightly closed and 250 μL of cis-2-butene was added. To determine the total amount of 1-MCP released and the amount of 1-MCP released per cm.sup.2 of label, the samples were analyzed on a gas chromatograph analogously to Example 1. Results are shown in Table 1.

(65) TABLE-US-00001 TABLE 1 Total 1-MCP released under 100% relative humidity Sample A Sample B Sample C Sample D 1-MCP (mg/cm.sup.2) 0.04255 0.04784 0.05125 0.05601 1-MCP (μL) 17.6 19.8 21.2 23.2

(66) To test the samples under 85% relative humidity conditions, the samples were each pasted in 900 mL vessels. To obtain a relative humidity of 85%, a container with a saturated solution of potassium chloride was placed into the vessel. At 20° C., relative humidity for potassium chloride is 85.11±0.29. The vessel was then tightly closed and 250 μL of cis-2-butene was added. The samples were analyzed on a gas chromatograph to measure the concentration of released 1-MCP from the sample over time. At each time interval, samples were removed from the vessels and the concentration was obtained by comparing the areas of the peaks (1-MCP and cis-2-butene). The results are shown in Tables 2-4 and FIGS. 16-23.

(67) TABLE-US-00002 TABLE 2 1-MCP released over time per cm.sup.2 of label (μL/L) at 85% relative humidity Time (h) Sample 1 Sample 2 1 — — 2 — — 3 1.18 0.46 4 2.10 1.51 5 2.79 2.35 6 2.91 2.72 7 3.35 3.18 9.5 4.17 3.84 26 5.81 5.28

(68) TABLE-US-00003 TABLE 3 1-MCP released over time per cm.sup.2 of label (μL/L) at 85% relative humidity Time (h) Sample 3 Sample 4 1.5 — — 2.5 1.03 1.03 3.5 1.68 1.47 5.5 2.83 3.04 17.5 5.25 5.77 19 5.23 6.22 20.5 5.25 6.24

(69) TABLE-US-00004 TABLE 4 1-MCP released over time per cm.sup.2 of label (μL/L) at 85% relative humidity Time [h] Sample 5 Sample 6 Sample 7 Sample 8 1 — — — — 3 0.74 0.78 1.11 0.67 4 1.18 1.2 1.53 1.02 6 1.71 1.78 1.71 1.66 20 2.41 2.82 2.63 2.84 21 2.48 2.65 2.56 2.53 25 2.74 3.09 2.47 2.8 27 3.22 3.47 3.2 3.23 68 3.22 3.94 2.94 3.47

(70) The release profiles of different label sizes were also analyzed. Labels were prepared as above, cut to size, and pasted into 2000 mL vessels. To obtain a relative humidity of 85%, a container with a saturated solution of potassium chloride was placed into the vessel. The vessel was then tightly closed and 250 μL of cis-2-butene was added. The samples were analyzed on a gas chromatograph to measure the concentration of released 1-MCP from the sample over time as described above for 100% relative humidity. The measurements are shown in Tables 5-6 and illustrated in FIGS. 24-29.

(71) TABLE-US-00005 TABLE 5 1-MCP released over time under 85% relative humidity for varying label sizes (μL/L) Time 5 cm.sup.2 10 cm.sup.2 20 cm.sup.2 40 cm.sup.2 0.5 — — — — 1 — — — — 1.5 — — — — 2 — — — — 2.5 — — — 0.09 3 — 0.15 0.21 0.25 3.5 — — 0.5  0.36 4 0.75 0.71 0.75 0.47 4.5 — 0.93 0.91 0.69 5 1.19 1.19 — 0.91 5.5 1.69 1.33 0.97 1.03 6 2.04 — 1.11 1.27 24 2.49 2.72 2.59 2.58

(72) TABLE-US-00006 TABLE 6 1-MCP released over time under 85% relative humidity 100 cm.sup.2 labels (μL/L) Time 100 cm2 100 cm2 (h) (Sample A) (Sample B) 0.5 — — 1 — — 1.5 — — 2 — — 2.5 — — 3 — — 3.5 0.07 0.04 4 0.12 0.11 5 0.28 0.22 6 0.52 0.38 7 0.74 0.59 24 2.35 2.08 27.5 2.21 2.18

Example 9

(73) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %), 1-methylcyclopropene/alpha-cyclodextrin complex (25 wt %), and pure alpha-cyclodextrin (25 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested for total amount of 1-MCP released and amount of 1-MCP released per cm.sup.2 of the label, under 100% relative humidity conditions or 85% relative humidity conditions.

(74) To test under 100% relative humidity conditions, a 6.4 cm×4.6 cm label (29.44 cm.sup.2) sample was placed in a 250 mL bottle and then 2 mL of distilled water was added. Next, the bottle was tightly closed and 250 μL of cis-2-butene was added. To determine the total amount of 1-MCP released and the amount of 1-MCP released per cm.sup.2 of label, the sample was analyzed on a gas chromatograph as described in Example A-8. The sample released 0.02364 mg/cm2 (or 9.8 μL) 1-MCP.

(75) Two sample labels with a surface area of 20 cm.sup.2 were tested under 85% relative humidity conditions as described in Example A-8. The results are shown in Table 7 and FIGS. 30-31.

(76) TABLE-US-00007 TABLE 7 1-MCP released over time per cm.sup.2 of label (μL/L) at 85% relative humidity Time (h) Sample 1 Sample 2 1 — — 2 — — 3.5 0.399 0.381 5 — 0.928 6 0.936 1.239 20.5 1.285 1.753 23 1.574 1.861 25 1.462 1.924

Example 10

(77) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (66.7 wt %), and 1-methylcyclopropene/alpha-cyclodextrin complex (33 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi). After drying at room temperature, labels were cut from the paper and tested for total amount of 1-MCP released and amount of 1-MCP released per cm.sup.2 of the label, under 100% relative humidity conditions or 85% relative humidity conditions.

(78) To test under 100% relative humidity conditions, a 6.4 cm×4.6 cm label (29.44 cm2) sample was placed in a 250 mL bottle and then 2 mL of distilled water was added. Next, the bottle was tightly closed and 250 μL of cis-2-butene was added. To determine the total amount of 1-MCP released and the amount of 1-MCP released per cm2 of label, the sample was analyzed on a gas chromatograph as described in Example A-8. The sample released 0.02264 mg/cm.sup.2 (or 9.4 μL) 1-MCP.

(79) Two sample labels with a surface area of 20 cm2 were tested under 85% relative humidity conditions as described in Example A-8. The results are shown in Table 8 and FIGS. 32-33.

(80) TABLE-US-00008 TABLE 8 1-MCP released over time per cm.sup.2 of label (μL/L) at 85% relative humidity Time (h) Sample 1 Sample 2 1 — — 2 — — 3.5 0.416 0.529 5 1.216 0.937 6 1.223 1.234 20.5 1.657 1.532 23 1.53 1.561 25 1.604 1.497

Example 11

(81) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %), 1-methylcyclopropene/alpha-cyclodextrin complex (25 wt %), and glucose (25 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi).

Example 12

(82) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %), 1-methylcyclopropene/alpha-cyclodextrin complex (12.5 wt %), and pure alpha-cyclodextrin (37.5 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi).

Example 13

(83) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %), 1-methylcyclopropene/alpha-cyclodextrin complex (12.5 wt %), and glucose (37.5 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi).

Example 14

(84) A dry mixture of poly(vinylpyrrolidone) (MW=10,000) (50 wt %), 1-methylcyclopropene/alpha-cyclodextrin complex (25 wt %), pure alpha-cyclodextrin (12.5 wt %), and glucose (12.5 wt %) was prepared. The dry mixture was combined with 2-propanol in an amount sufficient to form a paste as described in Example A-8. The resulting paste was applied to self-adhesive paper by screen printing (polyester mesh 64T, resolution 160 dpi).

B. Stick

Example 1

(85) Polyvinylpyrrolidone (PVP) (45 wt. %, MW=10,000), 1-MCP/α-cyclodextrin complex (5 wt. %, 1-MCP content=3.4%), cochineal red (0.5 wt. %), and isopropyl alcohol (49.5 wt. %) were placed in a round bottom flask. The contents of the flask were mixed using a magnetic stirrer for 0.5 hours at room temperature. Isopropanol was then removed at 40° C. under reduced pressure on a rotary evaporator. The resulting mass was formed in the form of a stick and then evenly spread on paper with a weight of 100 g/m.sup.2 and an area of 6.9 cm×7.8 cm. After drying, samples were prepared for analysis and tested for 1-MCP per 1 cm.sup.2 of support. The paper with the mass applied was cut and placed in a 250 mL bottle, then 2 mL distilled water was added to the bottle and sealed with a Mininert® valve plug, followed by 250 μL cis-2-butene with a gas-tight syringe. The samples were shaken for 30 minutes at a frequency of 600 cycles/min.

(86) The concentration of 1-MCP was determined against the standard, which was cis-2-butene, using a gas chromatograph equipped with a PoraBOND Q column: 25 m×0.25 mm (i.d.)×3 μm and a flame ionization detector (FID). Cis-2-butene was used as a standard because it has the same response from an FID detector as 1-methylcyclopropene. From a previously prepared test in a 250 mL bottle, 250 μL gas was withdrawn with a gas-tight syringe and injected into the above-mentioned column under the following conditions: temperature of the split/splitless dispenser 120° C.; isothermal 120° C., temperature of the FID 240° C. detector, split 20:1, carrier gas flow (helium) 50 cm/s. After a single application, the concentration of 1-MCP on the material as mentioned above was 0.0122 mg/cm.sup.2.

Example 2

(87) Coconut oil (53 wt. %), emulsifier SE-PF (20 wt. %), stearic acid (10 wt. %), beeswax (9.5 wt. %), cochineal red (0.5 wt. %), polyvinylpyrrolidone (PVP) (2 wt. %, MW=10,000), and a 1-MCP/α-cyclodextrin complex (5 wt. %, 3.3% 1-MCP) was mixed using a mechanical stirrer in a round bottom flask placed in an oil bath at 70° C. until a uniform consistency was obtained. The mass obtained was formed in the form of a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(88) After a single application, the concentration of 1-MCP on the material as mentioned above was 0.0106 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 3

(89) 1-Methylcyclopropene/α-cyclodextrin complex (50 wt. %, content of 1-MCP 3.3%), beeswax (24 wt. %), candelilla wax (24 wt. %), and polyvinylpyrrolidone (PVP) (2 wt. %, MW=10,000) were placed in a mortar. The substances were mixed for 15 minutes to obtain a uniform consistency. The obtained mass was formed in the form of a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(90) After a single application, the concentration of 1-MCP on the material as mentioned above was 0.007805 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 4

(91) Beeswax (24 wt. %), candelilla wax (24 wt. %), and polyvinylpyrrolidone (PVP) (2 wt %, MW=10,000) were placed in a beaker and heated to melt at 50° C., after which 1-MCP complex with α-cyclodextrin (50% by weight, 1-MCP content was 3.3%) was added. The ingredients were mixed to a homogeneous consistency. After cooling, the resulting mass was formed into a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(92) After a single application, the concentration of 1-MCP on the material as mentioned above is 0.01026 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 5

(93) 1-Methylcyclopropene/α-cyclodextrin complex (30 wt. %, 1-MCP content 3.3%), beeswax (20 wt. %), candelilla wax (20 wt. %), and polyvinylpyrrolidone (PVP) (30 wt. %) were placed in a mortar. The substances were mixed for 15 minutes to obtain a uniform consistency. The resulting mass was formed into a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(94) After a single application, the concentration of 1-MCP on the material as mentioned above was 0.02645 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 6

(95) Beeswax (20 wt. %) and candelilla wax (20 wt. %) were placed in a beaker and heated to melt at 50° C., after which 1-MCP/α-cyclodextrin complex (30 wt. %, 1-MCP content was 3.3%) and polyvinylpyrrolidone (PVP) (30 wt. %) were added. The components were mixed to a homogeneous consistency. After cooling, the resulting mass was formed into a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(96) After a single application, the concentration of 1-MCP on the material as mentioned above is 0.02186 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 7

(97) 1-Methylcyclopropene/α-cyclodextrin complex (35 wt. %, 1-MCP content 3.3%), glycerol (30 wt. %), and polyvinylpyrrolidone (PVP) (35 wt. %) were placed in a mortar. The substances were mixed for 15 minutes to obtain a uniform consistency. The resulting mass was formed into a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper. After a single application, the concentration of 1-MCP on the material as mentioned above was 0.02894 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

Example 8

(98) Beeswax (7.5 wt. %), candelilla wax (7.5 wt. %), and glycerol (15 wt. %) were placed in a beaker and heated to melt at 50° C., after which 1-MCP/α-cyclodextrin complex (30 wt %, 1-MCP content was 3.3%) and polyvinylpyrrolidone (PVP) (30 wt %) were added. The components were mixed to a homogeneous consistency. After cooling, the resulting mass was formed into a stick and tested for 1-MCP per 1 cm.sup.2 of 100 g/m.sup.2 paper.

(99) After a single application, the concentration of 1-MCP on the material as mentioned above was 0.02845 mg/cm.sup.2. The concentration was determined analogously to Example B-1.

(100) The 1-MCP concentration was also analyzed at 100% humidity at room temperature using the sticks prepared in Examples B-3 and B-4. The paper sheet with the mass applied was placed in a 900 mL glass vessel. A sponge soaked in water was inserted into the dish and then sealed, and 250 μL of cis-2-butene was introduced with a gas-tight syringe.

(101) The concentration was determined against the standard, which was cis-2-butene, using a gas chromatograph equipped with a PoraBOND Q column: 25 m×0.25 mm (i.d.)×3 μm and a flame ionization detector (FID). Cis-2-butene was used because it has the same response from an FID detector as 1-methylcyclopropene.

(102) For analysis, 250 μL gas was collected with a gas-tight syringe and injected into the above-mentioned column under the following conditions: temperature of the split/splitless dispenser 120° C.; isothermal 120° C., temperature of the FID 240° C. detector, split 20:1, carrier gas flow (helium) 50 cm/s.

(103) The analysis was performed on a gas chromatograph, testing the concentration of [μL/L] of 1-MCP released over time. The results are shown in FIGS. 4 and 5.

C. Packaging

Example 1

(104) Film Production

(105) 25% by weight of a 1-methylcyclopropene/α-cyclodextrin complex with 3.3% 1-MCP was mixed with 75% by weight of ethylene vinyl acetate copolymer (Evatane® 28-03) and placed in a co-rotating twin screw extruder BTSK 20/40D with block heating to 80° C. The composite was extruded through a 3 mm diameter nozzle at a speed of 2 kg/h. The extruded composite was cooled with air and then granulated mechanically.

(106) The content of 1-MCP was determined against a cis-2-butene standard using a gas chromatograph equipped with a flame ionization detector (FID) and a PoraBOND Q column: 25 m×0.25 mm (i.d.)×3 μm. The content of 1-MCP in the granulate was 0.42% by weight as calculated by the formula according to the CIPAC/4669/method.

(107) The granulate composite prepared in this way was coextruded with PET granulate to form a three-layer film in the ABA format where each A layer is 10% and the B layer 80% of the finished film. The addition of 1-MCP containing granules to layer A is 1% by weight.

(108) The co-extrusion process was carried out using a single-screw extruder at 260° C. to obtain a 0.5 mm thick film.

(109) The co-extruded film was analyzed with respect to MCP content using a PoraBOND Q column: 25 m×0.25 mm (i.d.)×3 μm and a gas chromatograph coupled with a triple quadrupole mass spectrometer (Shimadzu, GCMS-TQ8040). The analysis was carried out at 120° C. in product ion scan mode, 120° C. dispenser temperature, 1:1 split, 55 cm/s carrier gas flow.

(110) Analysis of the 1-MCP content in the film was done by crushing a sample of 100 cm.sup.2 of film and then placing it in a gas-tight vial with a volume of 25 mL in 100% humidity, then a standard was added, which was 250 nL cis-2-butene. After two hours of incubation, the analysis was performed by injecting 250 μL of gas withdrawn from the vial. FIG. 40 is an exemplary chromatogram of the released 1-methylcyclopropene. FIGS. 41 and 42 are mass spectra of the released 1-MCP and cis-butene reference standard, respectively. The 1-MCP content calculated against the standard was 10.1 nL/L from 1 cm.sup.2 of a 0.5 mm thick film.

(111) A basket was made of the film prepared in this way, and the content of 1-MCP was determined after the thermoforming process.

(112) A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.