JP2018178063A - Fluorine-based resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-modified fluorine-based resin film excellent in adhesion with rubber and having reduced coloring.SOLUTION: A fluorine-based resin film includes four elements of carbon, nitrogen, oxygen and fluorine at least on part of a surface area. In the area, with regard to total 100% of the four elements of carbon, nitrogen, oxygen and fluorine, a ratio of carbon is 45-70%, a ratio of nitrogen 0.1-5%, a ratio of oxygen is 13% or more and a ratio of fluorine is 35% or less.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fluorine-based resin film, and more particularly to a fluorine-based resin film in which a region of the surface is modified by plasma treatment.

  Since a fluorine-based resin film is generally extremely inactive, it is rubber-based in order to improve the chemical resistance, slipperiness and adhesion prevention property of various rubber products such as a stopper of a syringe and a stopper of a medicine vial. It is widely used as a film for covering the surface of the material (legs and tops). Moreover, since it is excellent in a weather resistance, it is used also as a protective member of a photovoltaic cell.

  However, since the fluorine-based resin film is extremely inactive, the adhesion and compatibility with other members such as rubber and the like are poor, and conventionally, the surface of the fluorine-based resin film has been subjected to a modification treatment in advance. Bonded to other parts such as Examples of such a modification treatment include chemical treatment, sputter etching treatment, plasma treatment and the like. For example, in order to improve adhesion, it is proposed that the fluorine / carbon elemental ratio (F / C) in the modified layer of the fluorine-based resin film be adjusted in the range of 0.8 to 1.7 by plasma treatment. (See Patent Document 1). In addition, in order to improve adhesion, the fluorine resin has a fluorine / carbon element ratio (F / C) of 1.12 or less and an oxygen / carbon element ratio (O / C) in the bonding surface layer portion with rubber. It is proposed to adjust to 0.08 or more (see Patent Document 2). Furthermore, in order to improve adhesion, it has been proposed to adjust the nitrogen / oxygen elemental ratio (N / O) of the surface treated portion to 0.15 or more (see Patent Document 3).

Japanese Patent Application Laid-Open No. 60-9734 JP 7-178875 A Unexamined-Japanese-Patent No. 2013-144759

  The present inventors modify the surface such that the adhesiveness of the fluorine-based resin film is sufficiently improved by using the techniques described in Patent Documents 1 to 3, whereby the fluorine-based resin film is colored and the appearance is improved. We found new technical issues that there is a risk of losing.

  The present invention has been made in view of the above background art, and an object thereof is to provide a surface-modified fluorine-based resin film which has excellent adhesion to rubber and reduced coloration.

  The inventors of the present invention conducted intensive studies to solve the above problems, and as a result, the ratio of the four elements of carbon, nitrogen, oxygen, and fluorine was specified in a partial region (surface modified region) of the fluorine resin film. By adjusting in the range, it has been found that it is possible to provide a surface-modified fluorine-based resin film which has excellent adhesion to rubber and reduced coloration. The present invention has been completed based on such findings.

That is, according to one aspect of the present invention,
A fluorine-based resin film containing four elements of carbon, nitrogen, oxygen and fluorine in at least a partial region of the surface,
In the above region, the ratio of carbon is 45% or more and 70% or less, and the ratio of nitrogen is 0.1% or more and 5% or less, based on 100% in total of four elements of carbon, nitrogen, oxygen, and fluorine. There is provided a fluorine-based resin film in which the proportion of oxygen is 13% or more and the proportion of fluorine is 35% or less.

  In an aspect of the present invention, in the region, a fluorine / carbon element ratio (F / C) is 0.70 or less, an oxygen / carbon element ratio (O / C) is 0.20 or more, and nitrogen / oxygen The element ratio (N / O) is preferably 0.01 or more and 0.20 or less.

  In the aspect of the present invention, it is preferable that b * in the L * a * b * color system is 4.0 or less in the region.

  In an aspect of the present invention, in the region, a * in the L * a * b * color system is preferably −4.0 or more and 4.0 or less.

  In the aspect of the present invention, it is preferable that the fluorine-based resin film contains a copolymer resin of ethylene and tetrafluoroethylene.

  In the aspect of the present invention, the fluorine-based resin film preferably contains a copolymer resin of ethylene and chlorotrifluoroethylene.

  In the embodiment of the present invention, it is preferable to be used for laminating to rubber.

Also, according to another aspect of the present invention,
There is provided a composite rubber molded body comprising the above-mentioned fluorine-based resin film and rubber.

  According to the present invention, by controlling the surface modification state by plasma treatment, it is possible to obtain a fluorine-based resin film which is excellent in adhesion to rubber and in which coloration is reduced.

It is a schematic block diagram which shows the plasma processing apparatus used for the plasma processing of the fluorine resin film of this invention. It is the cross-sectional schematic which showed one Embodiment of the composite rubber molded object (laminated rubber stopper) of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is the external appearance perspective view which showed one Embodiment of the composite rubber molded object (laminated rubber stopper) of this invention. It is the cross-sectional schematic which showed one Embodiment of the composite rubber molded object (laminated rubber stopper) of this invention.

<Surface modified fluorine resin film>
The surface-modified fluorine-based resin film of the present invention is a fluorine-based resin film containing four elements of carbon, nitrogen, oxygen and fluorine in a partial region (surface modified region) of the surface. The surface-modified fluorine-based resin film is inert and excellent in chemical resistance, solvent resistance, and slip resistance, and therefore, by laminating it on rubber, the chemical resistance is excellent on the surface of the rubber (legs and tops).・ It can impart solvent resistance, slipperiness and adhesion prevention.

  The fluorine-based resin film has a carbon ratio of 45% to 70%, preferably 50% to 68%, based on 100% in total of four elements of carbon, nitrogen, oxygen and fluorine in the surface modification region. Or less, more preferably 55% or more and 65% or less, the ratio of nitrogen is 0.1% or more and 5% or less, preferably 0.5% or more and 4% or less, and more preferably 1.0 % And 3.0% or less, the proportion of oxygen is 13% or more, preferably 14% or more and 30% or less, more preferably 15% or more and 25% or less, and the proportion of fluorine is 35% or less It is preferably 10% or more and 33% or less, and more preferably 15% or more and 30% or less. When the ratio of the four elements of carbon, nitrogen, oxygen and fluorine is in the above range in the surface modification region of the fluorine resin film, the fluorine resin film is excellent in adhesion to rubber and reduced in coloring. You can get it. The ratio of each element can be adjusted by controlling the conditions of the following reforming process.

  The fluorine-based resin film preferably has a fluorine / carbon element ratio (F / C) of 0.70 or less, more preferably 0.10 or more and 0.65 or less, and still more preferably in the surface modification region. The oxygen / carbon element ratio (O / C) is preferably 0.20 or more, more preferably 0.25 or more and 0.50 or less, and still more preferably 0. The nitrogen / oxygen elemental ratio (N / O) is preferably 0.01 or more and 0.20 or less, more preferably 0.03 or more and 0.15 or less. Preferably it is 0.05 or more and 0.12 or less. In the surface-modified region of the fluorine-based resin film, F / C, O / C, and N / O are in the above ranges to obtain a fluorine-based resin film having excellent adhesion to rubber and reduced coloration. be able to. In addition, each element ratio can be adjusted by controlling the conditions of the following modification treatment.

  The fluorine-based resin film preferably has a * of −4.0 or more and 4.0 or less, more preferably −2.0 or more, in the L * a * b * color system in the surface modification region. It is 0 or less, more preferably -1.0 or more and 1.0 or less, and b * in the L * a * b * color system is preferably 4.0 or less, more preferably -3.0 It is 3.0 or more, more preferably -2.0 or more and 2.0 or less. When a * and b * in the L * a * b * color system are in the above range in the surface modified region of the fluorine-based resin film, a fluorine-based resin film with reduced coloring can be obtained.

  The fluorine-based resin film used in the present invention is not particularly limited. For example, a copolymer resin of ethylene and tetrafluoroethylene (ETFE), a copolymer resin of ethylene and chlorotrifluoroethylene (ECTFE), Polytetrafluoroethylene resin (PTFE), perfluoroalkoxy resin (PFA) composed of copolymer of tetrafluoroethylene and perfluoroalkylvinylether, copolymer resin of tetrafluoroethylene and hexafluoropropylene (FEP), tetratetra Copolymer resin (EPE) of fluoroethylene, perfluoroalkylvinylether and hexafluoropropylene, polychlorotrifluoroethylene resin (PCTFE), vinylidene fluoride resin (PVDF), polyvinyl fluoride resin (PVF) Etc. The. Among them, a copolymer resin of ethylene and tetrafluoroethylene (ETFE) is preferable because it is easy to perform surface modification by plasma treatment and has chemical resistance, solvent resistance and slip resistance. Furthermore, modified type ethylene / tetrafluoroethylene copolymer resin (ETFE) can be used. The modified type ethylene / tetrafluoroethylene copolymer resin (ETFE) is preferably obtained by terpolymerizing ethylene, tetrafluoroethylene and a fluorine-containing vinyl monomer copolymerizable therewith.

<Reforming treatment>
The modification treatment of the surface of the fluorine-based resin film is not particularly limited, but treatment with a chemical solution, treatment with an electron beam, corona treatment, atmospheric pressure plasma treatment, low pressure plasma treatment and the like can be mentioned. From the viewpoint of productivity, corona treatment, atmospheric pressure plasma treatment, low pressure plasma treatment and the like are preferable. Low pressure plasma treatment is particularly preferable because the ratio of gas species for functional group introduction can be used in a wide range.

<Plasma treatment>
When the surface layer portion of the fluorine-based resin is activated by low-pressure plasma treatment or the like, fluorine atoms are released from the skeleton of the fluorine-based resin to generate carbon radicals. Thereafter, it bonds with oxygen in the atmosphere, and a hydrogen atom supplied from the atmosphere further forms a functional group such as a hydroxyl group, a carboxyl group, an aldehyde group, or a ketone group. When a hydrogen atom is bonded to the skeleton of the fluorine resin, the hydrogen atom is similarly separated from the skeleton of the fluorine resin to generate carbon radicals. Then, functional groups such as a hydroxyl group, a carboxyl group, an aldehyde group, and a ketone group are formed by bonding with oxygen in the atmosphere and further hydrogen atoms released from the atmosphere or hydrogen atoms supplied from the atmosphere.
Alternatively, due to oxygen radicals generated in the atmosphere by low pressure plasma treatment, abstraction of fluorine atoms from the skeleton of the fluorine resin and addition reaction of oxygen to the fluorine resin occur, and further, hydroxyl groups are supplied by hydrogen atoms supplied from the atmosphere. And oxygen-containing functional groups such as carboxyl group, aldehyde group and ketone group are formed. Further, when a hydrogen atom is bonded to the skeleton of the fluorine resin, similarly, the hydrogen atom is extracted from the skeleton of the fluorine resin and the addition reaction of oxygen to the fluorine resin occurs, and the extracted hydrogen atom is further generated. And hydrogen atoms supplied from the atmosphere form functional groups such as hydroxyl group, carboxyl group, aldehyde group and ketone group.
When the surface activated by the low pressure plasma treatment returns to atmospheric pressure, functional groups derived from oxygen and nitrogen in air are formed. For this reason, oxygen or nitrogen is detected on the surface even under the processing condition in which there is no oxygen or nitrogen in the plasma atmosphere.
The surface layer in which these functional groups come to be present is considered to be such that the affinity and reactivity with other resins are significantly improved, and the adhesiveness of the fluorine-based resin is developed.

  On the other hand, when the carbon concentration in the surface layer is increased by plasma treatment, it becomes easy to be colored. In the present invention, by optimizing the plasma processing conditions, the carbon concentration in the surface layer is controlled, the oxygen concentration is increased, nitrogen is introduced, and the fluorine is reduced, thereby improving the adhesion and reducing the coloration. can do.

<Plasma processing device>
From the ease of control of the plasma atmosphere and the degree of freedom of usable gases, an apparatus capable of low pressure plasma processing is preferable. As the low pressure plasma processing apparatus, an ICP type plasma processing apparatus, a parallel plate type plasma processing apparatus, a roll-to-roll type plasma processing apparatus, or the like can be used. From the viewpoint of productivity, a roll-to-roll type plasma processing apparatus is preferable.
As a power source used for plasma generation, conventionally known power sources such as a high frequency power source and a pulse wave power source can be used. If the frequency of the power supply is in the range of 100 kHz or less, the degree of freedom of the gas is high, and a large proportion of gas types can be used to actively introduce functional groups. Such gases include O ₂ , CO, CO ₂ , NH ₃ , N ₂ O, SO ₂ , H ₂ S, and the like.

  A schematic configuration diagram is shown in FIG. 1 as an example of a roll-to-roll type plasma processing apparatus. The plasma processing apparatus shown in FIG. 1 is an apparatus for producing a surface-modified fluorine-based resin film 50 by subjecting the fluorine-based resin film 51 to a surface-modifying treatment by subjecting the fluorine-based resin film 51 to plasma treatment. It is. Such plasma processing apparatus includes a chamber 11, a film supply unit 12 and a film winding unit 13 disposed in the chamber 11, a mask 52 and a magnetic field generation unit 60 in the chamber 11, and plasma treatment in the chamber 11. And a processing gas supply unit 40 for supplying a processing gas for processing.

  Among them, the film supply unit 12 includes a supply roller 12 a on which the fluorine-based resin film 51 is wound and which supplies the fluorine-based resin film 51. In addition, the film winding unit 13 includes a winding roller 13 a on which the surface-modified fluorine-based resin film 50 is wound and which winds the surface-modified fluorine-based resin film 50. Furthermore, a rotary main roll 14 is disposed between the film supply unit 12 and the film winding unit 13. A fluorine-based resin film 51 is wound around the main roll 14 along the surface thereof, and the fluorine-based resin film 51 on the main roll 14 is subjected to plasma treatment. Furthermore, a plurality of fluorocarbon resin films 51 are guided from the film supply unit 12 to the film winding unit 13 between the film supply unit 12 and the main roll 14 and between the main roll 14 and the film winding unit 13. Guide rolls 16 are provided. The film supply unit 12, the film winding unit 13, the main roll 14, and the guide roll 16 constitute a roll-to-roll film transport device 15. Further, an exhaust pump 17 for evacuating the inside of the chamber 11 is connected to the chamber 11 via a connecting pipe 18. Further, the connecting pipe 18 is provided with a valve 19 for adjusting the degree of vacuum (pressure) in the chamber 11.

  Furthermore, the processing gas supply unit 40 includes a gas nozzle 34 for ejecting the processing gas into the chamber 11, gas supply pipes 44, 45, and 46 for supplying the processing gas, and processing gas storage units 41 and 42 for storing the processing gas. And 43. Note that mass flow controllers (MFC) 47, 48, 49 for controlling the flow rate of gas are provided in the gas supply pipes 44, 45, 46, respectively. As the supply gas, for example, three types of argon, helium and oxygen can be used.

  Furthermore, at a position facing the opening of the mask 52 in the chamber 11, a magnetic field generation unit 60 including a magnet 61 used in a sputtering apparatus is provided. A 40 kHz high frequency power supply is connected to the main roll. The plasma P is generated by the introduction of the processing gas, the adjustment of the pressure in the chamber 11, and the introduction of the high frequency power. By installing the magnetic field generating unit 60 and introducing high frequency power to the main roll, a region with high plasma density is formed in the vicinity of the fluorine-based resin film 51, and it becomes possible to perform plasma processing efficiently. In the chamber 11, a partition wall 65 is provided. The partition wall 65 plays a role of spreading the generated plasma P to the film supply unit 12 and the film winding unit 13 side, and suppressing deposition of a product generated by plasma processing on the film supply unit 12 and the film winding unit 13 side. Play.

<Compound rubber molding>
The composite rubber molding of the present invention comprises the above-mentioned fluorine-based resin film and rubber. By laminating the surface-modified side of the fluorine-based resin film so as to face the rubber, excellent chemical resistance, solvent resistance, slipperiness, and excellent chemical resistance on the surface of the rubber are realized while achieving good adhesion between the two. An adhesion preventing property etc. can be provided.

  As a compound rubber molding of the present invention, for example, a laminated rubber stopper in which the above-mentioned fluorine-based resin film is coated on the leg portion of the rubber stopper can be mentioned. In FIG. 2, the cross-sectional schematic of a lamination rubber stopper is shown, and the external appearance perspective view of one Embodiment of the lamination rubber stopper 4 of this invention is shown in FIG. The laminated rubber plug 1 shown in FIG. 2 is obtained by laminating the surface modified side of the surface modified fluorine-based resin film 2 on the leg of the rubber plug 3. With such a configuration, for example, when used as a stopper for a container containing a liquid, it is effective to prevent the liquid contained in the container from leaking while preventing the components contained in the rubber from eluting into the liquid. Can be prevented. In addition, the laminated rubber stopper according to the present invention is excellent in that it does not cause coloring of the fluorine resin, unlike the one obtained by the treatment with the conventional metal sodium complex.

  Another example of the composite rubber molded article of the present invention is a laminated rubber stopper in which the top surface portion of the rubber stopper is covered with the above-mentioned fluorine-based resin film. FIG. 4 shows a schematic cross-sectional view of the laminated rubber stopper. The laminated rubber stopper 5 shown in FIG. 4 is obtained by laminating the surface modification side of the surface modified fluorine-based resin film 6 on the top surface portion of the rubber stopper 7. With such a configuration, it can be used as a rubber stopper for a lyophilization vial. As a method of using this rubber plug, the rubber plug is half-stopped in the mouth of a vial filled with a drug solution, and in this state, it is put into a lyophilizer, and the drug solution is freeze-dried. Then, the rubber stopper is completely plugged in the same storage. At this time, by laminating the fluorocarbon resin film, it is possible to prevent the rubber stopper from adhering to the stopper press plate.

  Such a laminated rubber stopper may be obtained by in-mold molding a general rubber stopper with the fluorine resin laminated film according to the present invention. Examples of rubber materials used for such rubber plugs include butyl rubber, chlorinated butyl rubber, brominated butyl rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, ethylene-propylene rubber, silicone rubber and the like. Among them, chlorinated butyl rubber is particularly preferable from the viewpoint of the barrier property.

<Production of surface-modified fluorine resin film>
Example 1
As a fluorine-based resin film, a 300 mm wide ETFE film (manufactured by Daikin Corporation, Neoflon EF-0050) is passed through the roll-to-roll type plasma processing apparatus described above, the chamber is closed and the pressure is reduced to 0.01 Pa or less 200 sccm of Ar and 1500 sccm of oxygen were introduced. After adjusting the evacuation amount and adjusting the pressure in the vacuum chamber to 8 Pa, the power was set to 370 W and plasma treatment was performed. The transport speed of the fluorine-based resin film was 4.2 m / min, and the plasma treatment was repeated three times. After completion of the plasma treatment, discharge and gas supply were stopped, the pressure was reduced to 0.01 Pa or less, and the pressure was returned to atmospheric pressure to obtain a surface-modified fluorine-based resin film.

[Examples 2 to 19] [Comparative Examples 1 to 12]
Plasma treatment was carried out in the same manner as in Example 1 except that the plasma treatment conditions shown in Table 1 were changed to obtain a surface-modified fluorine-based resin film. In Examples 17 to 19 and Comparative Example 12, an ECTFE film (manufactured by Denka Co., Ltd., TEFKA) was used as the fluorine-based resin film.

<Performance test of surface-modified fluorinated resin film>
The following various performance evaluation tests were implemented about the surface-modified fluorine resin film obtained in Examples 1-19 and Comparative Examples 1-12. In addition, in Example 2 and Example 11, after performing a plasma processing, after performing normal temperature storage for 3 months, the following various performance evaluation tests were implemented.

[Measurement of color]
Place a sample of a surface-modified fluorocarbon resin film to be measured on a white calibration plate using a spectrophotometer CM-600d manufactured by Komikami Norta, and reflect it using the L * a * b * color system. Color was measured to evaluate the colorability. Measurement conditions were set to SCE (regular reflection light removal), 10 ° visual field, and D65 light source. The measurement results were as shown in Table 2.

[Measurement of surface composition]
Using a X-ray photoelectron spectrometer (ESCA-3400 manufactured by KRATOS), C1s, N1s, O1s, and F1s were measured under the conditions described in Table 3 as X-ray guns: MgKα, 20 mA, and 10 kV. Using analysis software, draw a background by the Shirley method to the peak of each element obtained by measurement, and calculate the element concentration in the plasma treatment area of the surface-modified fluorinated resin film from the integrated intensity (area) of the peak of each element did. The required elemental ratio was calculated from the obtained elemental concentration. The measurement results were as shown in Table 2.

[Adhesive evaluation during molding]
A rubber plug with a leg length of 10 mm, a leg diameter of 13 mm, a top thickness of 3 mm, and a top outer diameter of 19 mm, with the plasma-treated surface of the surface-modified fluorine resin film facing the unvulcanized butyl rubber sheet. In the upper and lower molds adjusted to the dimensions of (1), the film was made to be in contact with the top surface side of the rubber stopper, and was vulcanized and formed by a vacuum press.
About the obtained rubber stoppers (each 2 pieces), the adhesiveness (peelability) in a burr | flash part was confirmed visually, and the following references | standards evaluated. However, the mold temperature at molding was 170 ± 3 ° C., the vulcanization time was 420 seconds, and the film preheating time was 30 seconds. The evaluation results were as shown in Table 2.
(Evaluation criteria)
○: The surface-modified fluorinated resin film did not peel off at the burrs of the rubber stopper.
X: The surface-modified fluorinated resin film peeled off at the burr part of the rubber plug.

[Adhesive evaluation of sheet]
The plasma-treated surface of the surface-modified fluorine-based resin film and an unvulcanized rubber sheet (Exsobutyl manufactured by Exxon Chemical Co., Ltd., thickness 1 mm) are superposed and heated at 175 ° C. for 30 seconds for vulcanization and heating. Crimp lamination was performed to obtain a composite rubber sheet.
About the obtained composite rubber sheet, in order to investigate the adhesiveness of a film and a rubber substrate, according to JIS K 6854-2, a sample of the composite rubber sheet is pulled with a peeling angle at 180 ° with a peeling angle of 180 °, and a peeling test is carried out And evaluated according to the following criteria. The evaluation results were as shown in Table 2.
(Evaluation criteria)
○: Peeling strength was 5 N / cm or more.
X: Peeling strength was less than 5 N / cm.

1: Laminated rubber stopper 2: Surface modified fluorinated resin film 3: Rubber stopper 4: Laminated rubber stopper 5: Laminated rubber stopper 6: Surface modified fluorinated resin film 7: Rubber stopper P: Plasma 11: Chamber 12: Film Supply part 12a: Film roller 13: Film take-up part 13a: Take-up roller 14: Main roll 15: Film conveyance device 16: Guide roll 17: Exhaust pump 18: Connection pipe 19: Valve 34: Gas nozzle
40: Process gas supply part 41, 42, 43: Gas cylinder 44, 45, 46: Gas supply pipe 47, 48, 49: Mass flow controller 50: Surface-modified fluorine resin film 51: Fluoro resin film 52: Mask 60: Magnetic field generator 61: Magnet 65: Partition wall

Claims (8)

A fluorine-based resin film containing four elements of carbon, nitrogen, oxygen and fluorine in at least a partial region of the surface,
In the above region, the ratio of carbon is 45% or more and 70% or less, and the ratio of nitrogen is 0.1% or more and 5% or less, based on 100% in total of four elements of carbon, nitrogen, oxygen, and fluorine. A fluorine-based resin film in which the proportion of oxygen is 13% or more and the proportion of fluorine is 35% or less.   In the above region, the fluorine / carbon element ratio (F / C) is 0.70 or less, the oxygen / carbon element ratio (O / C) is 0.20 or more, and the nitrogen / oxygen element ratio (N / O) The fluorine-based resin film according to claim 1, wherein is 0.01 or more and 0.20 or less.   The fluorine resin film according to claim 1 or 2, wherein b * in the L * a * b * color system is 4.0 or less in the region.   The fluorine resin film according to any one of claims 1 to 3, wherein a * in the L * a * b * color system is -4.0 or more and 4.0 or less in the region.   5. The fluorine-based resin film according to any one of 1 to 4 above, wherein the fluorine-based resin film contains a copolymer resin of ethylene and tetrafluoroethylene.   5. The fluorine-based resin film according to any one of 1 to 5 above, wherein the fluorine-based resin film comprises a copolymer resin of ethylene and chlorotrifluoroethylene.   7. The fluorine-based resin film according to any one of 1 to 6, which is used for laminating on rubber.   The composite rubber molded object provided with the fluorine resin film as described in any one of Claims 1-7, and rubber | gum.

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