JP2017193658A - Adhesive composition and adhesive sheet prepared therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition that contains rubber, has excellent adhesive force, and sufficiently reduces the warps and wrinkles and an adhesive sheet prepared therewith.SOLUTION: An adhesive composition contains (A) a rubber component having a diene skeleton, (B) a monomer and/or an oligomer with the number of ethylenically unsaturated groups of 6 or more, and (C) a radical generator composed of an organic peroxide. Preferably, the (C) radical generator composed of an organic peroxide has an aromatic group in one molecule, and also has a symmetrical structure.SELECTED DRAWING: None

Description

  The present invention relates to an adhesive composition and an adhesive sheet using the same.

  Adhesive sheets formed with a thin film of uniform thickness on the base material can be bonded to the surface, simplifying the process and reducing the weight. It is used. As an adhesive composition used for an adhesive sheet, a thermosetting adhesive composition containing an epoxy resin, an acrylic resin, and a curing agent so as to have adhesiveness by heating is disclosed (patent) Reference 1). However, since the adhesive composition disclosed here uses an epoxy resin, the curing shrinkage when the adhesive is cured is large, and depending on the choice of the adherend when it is adhered to the adherend In some cases, warpage of the adherend and generation of wrinkles became a problem.

JP 2013-107957 A

  By making the adhesive composition for adhesive sheets into a composition containing rubber, there are advantages such as shrinkage during curing and stress concentration generated by thermal shock can be eased, and problems of warping and wrinkles can be solved it is conceivable that. However, the conventional adhesive composition containing rubber has a problem of low adhesive strength.

  The present invention advantageously solves the above problems, includes rubber, has excellent adhesive strength, relaxes stress concentration caused by thermal shock, and sufficiently suppresses and reduces warpage and wrinkles. It is an object to provide an adhesive composition that can be used and an adhesive sheet using the same.

  As a result of intensive studies to solve the above problems, the present inventor comprises a rubber component having a diene skeleton, a monomer and / or oligomer having 6 or more ethylenically unsaturated groups, and an organic peroxide. It has been found that a composition containing a radical generator has rubber elasticity after heating for curing and is excellent in adhesive strength, and the adhesive composition of the present invention was obtained therefrom.

  The adhesive composition of the present invention comprises (A) a rubber component having a diene skeleton, (B) a monomer and / or oligomer having 6 or more ethylenically unsaturated groups, and (C) an organic peroxide. And a radical generator.

In the adhesive composition of the present invention, it is preferable that the (C) radical generator has an aromatic group in one molecule and has a symmetrical structure. Moreover, it is preferable that the adhesive composition of this invention contains (D) tackifying resin further, In this case, the haze of the adhesive composition containing (D) tackifying resin contains the said (D) component. Higher than the haze of the non-adhesive composition is more preferred.
The adhesive sheet of the present invention is characterized by using the above adhesive composition.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the adhesive composition which has rubber | gum and has the outstanding adhesive force, and can fully suppress and reduce curvature and wrinkles, and an adhesive sheet using the same.

Hereinafter, the adhesive composition and adhesive sheet of the present invention will be described more specifically.
The adhesive composition of the present invention comprises (A) a rubber component having a diene skeleton, (B) a monomer and / or oligomer having 6 or more ethylenically unsaturated groups, and (C) an organic peroxide. And a radical generator. (A) a rubber component having a diene skeleton, (B) a monomer and / or oligomer having 6 or more ethylenically unsaturated groups, and (C) a radical generator composed of an organic peroxide. Depending on the composition, the adhesive composition of the present invention has excellent adhesive force, and can sufficiently suppress and reduce warpage and wrinkles.

  Each component contained in the adhesive composition of the present invention will be described.

<(A) Rubber component having a diene skeleton>
In the present invention, examples of the rubber component (A) having a diene skeleton include isoprene rubber, butadiene rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, chloroprene rubber, natural rubber, and butyl rubber.

  The adhesive composition of the present invention includes (A) a rubber component having a diene skeleton, and after curing by heating, the rubber component having the (A) diene skeleton is crosslinked to have rubber elasticity. . Therefore, it is possible to provide an adhesive that can alleviate shrinkage during curing and stress concentration caused by thermal shock and sufficiently suppress and reduce warpage and wrinkles.

<(B) Monomer and / or oligomer having 6 or more ethylenically unsaturated groups>
(B) The monomer and / or oligomer having 6 or more ethylenically unsaturated groups has an effect as a crosslinking agent for the rubber component having the (A) diene skeleton, and imparts adhesive force. When the number of ethylenically unsaturated groups of the monomer and / or oligomer is 6 or more, the adhesive force is remarkably improved as compared with those having an ethylenically unsaturated group of less than 6. Also, those having an ethylenically unsaturated group of less than 6 are not preferred because gas may be generated during heating.

  As the monomer and / or oligomer having 6 or more ethylenically unsaturated groups, for example, a polyfunctional (meth) acrylate having 6 or more ethylenically unsaturated groups can be used. The oligomer preferably has a number average molecular weight of 10,000 or less. The number average molecular weight in the present invention refers to the number average molecular weight in terms of polystyrene when GPC analysis is performed using tetrahydrofuran as a solvent. From the viewpoint of availability, the number of ethylenically unsaturated groups is preferably 15 or less. In the present invention, (meth) acrylate means acrylate or methacrylate.

  Examples of the polyfunctional (meth) acrylate having 6 or more ethylenically unsaturated groups include known polyester (meth) acrylates, polyether (meth) acrylates, and epoxy having 6 or more ethylenically unsaturated groups. (Meth) acrylate, urethane (meth) acrylate, silicone (meth) acrylate, and the like. These polyfunctional (meth) acrylates having 6 or more ethylenically unsaturated groups can be used alone or in combination of two or more.

  (B) The lower limit of the amount of the monomer and / or oligomer having 6 or more ethylenically unsaturated groups is preferably 1 part by mass with respect to 100 parts by mass of the rubber component (A) having a diene skeleton. More preferably, it is a part. The upper limit of the amount of the monomer and / or oligomer having 6 or more ethylenically unsaturated groups is preferably 20 parts by mass, and 15 parts by mass with respect to 100 parts by mass of the rubber component (A) having a diene skeleton. It is more preferable. By setting it as the said range, adhesive force can be adjusted to a more suitable range.

<(C) Radical generator composed of organic peroxide>
The adhesive composition of the present invention includes (C) a radical generator composed of an organic peroxide. (C) A radical generator composed of an organic peroxide generates radicals by heating, and (A) a rubber component having a diene skeleton and a monomer and / or oligomer having an ethylenically unsaturated group are crosslinked. In general, the radical generator includes an azo compound in addition to the organic peroxide, but the adhesive composition of the present invention uses a radical generator composed of an organic peroxide, so that it can be compared with an azo compound or the like. Excellent adhesion can be obtained.

  Examples of radical generators composed of organic peroxides include t-butyl-2-ethylperoxyhexanoate, dilauroyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate. Art, 1,1-di (t-hexylperoxy) cyclohexanone, di-t-butyl peroxide, t-butylcumyl peroxide, 1,1-di (t-hexylperoxy) -3,3,5- Trimethylcyclohexane, t-amylperoxy-2-ethylhexanoate, di (2-t-butylperoxyisopropyl) benzene, dibenzoyl peroxide, 1,1′-di (t-butylperoxy) cyclohexane, di (3,5,5-trimethylhexanoyl) peroxide, t-butylperoxyneodecanoate, -Hexylperoxyneodecanoate, dicumyl peroxide, di-t-hexyl peroxide, di (3-methylbenzoyl) peroxide, di (4-methylbenzoyl) peroxide, di-isopropylbenzene hydroperoxide, Cumene hydroperoxide, t-butyl hydroperoxide, t-butyl peroxylaurate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, 2,5-dimethyl-2,5-di (Benzoylperoxy) hexane, t-butylperoxyacetate, t-butylperoxybenzoate and the like can be mentioned. One of these can be used, or two or more can be used in combination. Among these, those having an aromatic group in the skeleton such as dicumyl peroxide, dibenzoyl peroxide, and t-butyl peroxybenzoate are preferable. A radical generator composed of an organic peroxide can be appropriately selected according to processing conditions.

As the radical generator composed of an organic peroxide, those having an aromatic group in one molecule and a symmetrical structure are particularly preferable. Here, the organic peroxide having a symmetric structure refers to one represented by the following general formula (1).
R1-O-O-R1 (1)
Since the radical generator has an aromatic group in one molecule and a symmetrical structure, it can dissociate oxygen radicals equivalently, has high reaction efficiency, and has mechanical strength that can withstand practical use. An adhesive composition can be obtained. The above-mentioned dicumyl peroxide and dibenzoyl peroxide have an aromatic group in one molecule and have a symmetrical structure.

  (C) The lower limit of the compounding amount of the radical generator is preferably 0.001 part by mass and more preferably 0.005 part by mass with respect to 100 parts by mass of the rubber component having the (A) diene skeleton. Preferably, it is 0.01 mass part. (C) The upper limit of the blending amount of the radical generator is preferably 5 parts by mass, more preferably 1 part by mass with respect to 100 parts by mass of the rubber component (A) having a diene skeleton. 2 parts by mass is particularly preferred. By setting it as said range, the bridge | crosslinking of adhesive composition can be adjusted to a more suitable range.

<(D) Tackifying resin>
The adhesive composition of this invention can contain (D) tackifying resin. (D) The adhesive force can be improved by including a tackifier resin. Moreover, tackiness can be imparted to the uncured adhesive composition. The adhesive composition having tackiness does not require thermocompression when temporarily attached to the adherend of the adhesive composition, and can improve workability.

  Tackifying resins include styrene resins, ethylene-vinyl acetate resins, xylene resins, terpene resins, phenol resins, rosins, polymerized rosins, disproportionated rosins and their derivatives, polyterpene resins, terpene phenols, rosin phenols and other phenol-modified resins Alkylphenol resins, coumarone-indene resins, xylene resins, aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic hydrocarbon resins and hydrogenated products thereof.

The tackifying resin is preferably a resin in which the haze of the adhesive composition containing (D) the tackifying resin is higher than the haze of the adhesive composition not containing the component (D). In other words, it is preferably a resin that increases the haze of the adhesive composition.
A method for measuring the haze of the adhesive composition will be described later.
(D) By selecting a resin in which the haze of the adhesive composition containing the tackifying resin is higher than the haze of the adhesive composition not containing the component (D), the adhesive composition Adhesive strength can be improved. On the other hand, when a resin is added such that the haze of the adhesive composition containing the (D) tackifying resin is equal to or less than the haze of the adhesive composition not containing the component (D), the (D) ) It is not preferable because the adhesiveness is lower than that of the adhesive composition containing no component.
(D) One type or two or more types of tackifying resins can be used in combination.

  The compounding amount of the tackifying resin is preferably 5 to 50 parts by mass and more preferably 15 to 35 parts by mass with respect to 100 parts by mass of the rubber component (A) having a diene skeleton.

  As other additives that can be further blended in the adhesive composition, for example, rubber other than the rubber component (A) having a diene skeleton as the elastomer component, for example, ethylene propylene rubber, urethane rubber, fluorine rubber, acrylic rubber, etc. Solid or liquid rubber, polyurethane, urethane prepolymer and the like. Also contains various fillers, functional fillers, antioxidants, UV absorbers, colorants, flame retardants, antifoaming agents, leveling agents, lubricants, dispersants, processing aids, plasticizers, coupling agents, etc. May be.

  The adhesive composition of the present invention comprises (A) a rubber component having a diene skeleton, (B) a monomer and / or oligomer having 6 or more ethylenically unsaturated groups, and (C) an organic peroxide. The peel strength can be adjusted by blending the radical generating agent, and (D) a tackifier resin and other additives, which are blended as necessary, in appropriate amounts.

  The adhesive composition of this invention can be obtained by mixing each component mentioned above in arbitrary orders. The raw materials can be mixed using a mixer or kneader such as a mixing roll, a planetary mixer, a butterfly mixer, a kneader, a single screw or twin screw extruder.

  Moreover, when the adhesive composition has tackiness at room temperature, workability is improved during temporary attachment. When the adhesive composition does not have tackiness at room temperature, it can be thermocompression bonded after being processed into the adhesive sheet of the present invention.

  Next, the adhesive sheet of the present invention will be described.

  The adhesive sheet of the present invention has an adhesive layer formed from the adhesive composition. Therefore, the adhesive sheet of the present invention comprises only the adhesive layer by peeling off the adhesive layer formed by applying the adhesive composition on the surface of the release film from the release film. May be. Moreover, what laminated | stacked the adhesive bond layer formed by apply | coating the said adhesive composition to at least one surface of a base material may be used. Hereinafter, the release film, the substrate, and the adhesive layer will be described.

  As release films, polyethylene film, polypropylene film, polymethylpentene (TPX) film, polyethylene terephthalate (PET) film, polyethylene film with silicone release agent, polypropylene film and PET film, polyimide film, polyphenylene sulfide film, polyethylene resin Examples thereof include coated paper, polypropylene resin coated paper, and TPX resin coated paper. The thickness of the release film is preferably 12 to 250 μm for a film base and 50 to 300 μm for a paper base, but an appropriate thickness may be selected as necessary.

  The substrate is not particularly limited and may be appropriately selected depending on the use of the adhesive sheet. Polyethylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, polycarbonate, triacetyl cellulose, aramid, polyimide, polyamide, polyphenylene sulfide, Examples include films made of synthetic resins such as polyetherimide, polyethersulfone, aromatic polyamide, and polysulfone, nonwoven fabrics, and paper. These substrates may be transparent or colored. Coloring can be performed by a method of blending various pigments or dyes into the constituent material of the substrate. Further, the surface of the substrate does not need to be smooth, and the surface may be processed into a mat shape.

  The thickness of a base material can be suitably selected according to the application to apply.

  What is necessary is just to select the thickness of the adhesive bond layer in an adhesive sheet suitably according to the use of an adhesive sheet. The lower limit is preferably about 1 μm, and more preferably 5 μm. The upper limit is preferably about 1000 μm, more preferably 400 μm, and even more preferably 200 μm. By setting the thickness of the adhesive composition to 1 μm or more, for example, it is possible to follow an adherend having irregularities, so that stable adhesive performance can be maintained. By setting the thickness of the adhesive composition to 1000 μm or less, it can be suitably used for applications that require thinning.

Next, the manufacturing method of the adhesive sheet of this invention is demonstrated.
First, the adhesive composition of the present invention is dissolved and / or dispersed in an appropriate solvent to prepare an adhesive layer forming coating solution having a solid content concentration of about 30 to 90% by mass. In the case where a release film is used in accordance with a conventional method, the adhesive layer forming coating solution is coated and dried on the surface of the release film, and formed into a film or sheet to form an adhesive. The adhesive sheet consists of only layers. Moreover, when using a base material instead of a mold release film, it apply | coats so that the surface of the single side | surface or both surfaces of a base material may be coat | covered, and it is set as an adhesive sheet by the method of drying this.

  The application method of the adhesive layer forming coating liquid is not particularly limited, and includes a wire bar, applicator, brush, spray, roller, gravure coater, die coater, lip coater, comma coater, knife coater, reverse coater, spin coater, etc. A conventionally known coating method using can be used. In addition, you may surface-treat in advance the surface of the release film and base material which apply | coat an adhesive bond layer formation coating liquid as needed.

  There is no restriction | limiting in particular also about the drying method of adhesive layer formation coating liquid, Conventionally well-known drying methods, such as hot air drying and reduced pressure drying, can be utilized. The drying conditions may be appropriately set according to the type of adhesive composition, the type of solvent used in the adhesive layer forming coating solution, the type of radical generator, the thickness of the adhesive layer, etc. It is common to perform drying at a temperature of about ~ 200 ° C.

  The adhesive sheet of this invention can be used for the use of a well-known and usual adhesive sheet. For example, adhesion between materials with different coefficient of linear expansion (CTE), adhesive sheet with reworkability, anisotropic conductive adhesive sheet, heat dissipation adhesive sheet, adhesive sheet that can follow the expansion and contraction of the material, silicon-based and urethane-based It is suitably used as an adhesive sheet with vibration resistance and an alternative to an adhesive sheet.

  The adhesive sheet of the present invention preferably has a peel strength of 7 N / cm or more, and more preferably a peel strength of 10 N / cm or more. When it is 7 N / cm or more, it has sufficient adhesive strength to withstand practical use.

  EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated concretely, this invention is not limited only to these Examples. In the following description, “part” means part by mass unless otherwise specified.

[Examples 1-9, Comparative Examples 1-3]
Each component of the rubber component having a diene skeleton shown in Table 1, the monomer and / or oligomer having an ethylenically unsaturated group, the radical generator, and the tackifier resin is blended in the ratio (unit: part) shown in Table 1. The mixture was stirred and mixed with separately prepared toluene and degassed under reduced pressure. After defoaming, an applicator was used on a release film (polyethylene terephthalate film with a silicone release agent) so as to have a dry thickness of 100 μm. Examples 1 to 9 and Comparative Examples 1 and 2 Was dried at 130 ° C. for 3 minutes, and Comparative Example 3 was dried at 60 ° C. for 30 minutes. After drying, the release film was peeled off to obtain an adhesive sheet.

In Tables 1 and 2, the following were used as components A1, A2, B1 to B6, C1 to C4, and D1 to D4.
(A) component (rubber component having a diene skeleton)
A1: Styrene butadiene rubber (styrene content: 25%, Mooney viscosity: 47)
A2: Acrylonitrile butadiene rubber (bound acrylonitrile content: 33.5%, Mooney viscosity: 27)
Component (B) (monomer and / or oligomer having an ethylenically unsaturated group)
B1: Dipentaerythritol hexaacrylate, a kind of polyester acrylate, number of ethylenically unsaturated groups: 6)
B2: Urethane acrylate (trade name: U-6LPA (manufactured by Shin-Nakamura Chemical Co., Ltd., number of ethylenically unsaturated groups: 6)
B3: Urethane acrylate (trade name: U-10PA (manufactured by Shin-Nakamura Chemical Co., Ltd., number of ethylenically unsaturated groups: 10)
B4: Urethane acrylate (trade name: U-15HA80E (manufactured by Shin-Nakamura Chemical Co., Ltd., number of ethylenically unsaturated groups: 15)
B5: Pentaerythritol tetraacrylate, number of ethylenically unsaturated groups: 4)
B6: Trimethylolpropane triacrylate, number of ethylenically unsaturated groups: 3)
Component (C) (radical generator)
C1: Dicumyl peroxide C2: Dibenzoyl peroxide C3: 2,2′-azobis (2-methylpropionic acid) dimethyl C4: t-butyl peroxybenzoate (D) component (tackifying resin)
D1: Ethylene-vinyl acetate resin (trade name: Everflex EV45LX, manufactured by Mitsui DuPont Polychemical Co., Ltd.)
D2: Xylene resin (trade name: Nikanol HP120, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
D3: Terpene resin (trade name: Clearon M115, manufactured by Yasuhara Chemical Co., Ltd.)
D4: Phenolic resin (trade name: MHEC7851-4H, manufactured by Meiwa Kasei Co., Ltd.)

The peel strength of the obtained adhesive sheet was examined. The peel strength test uses stainless steel (thickness 50 μm) and bright annealed stainless steel (thickness 1.5 mm) as the adherend, and is bonded by a hand roller with an adhesive sheet sandwiched at 180 ° C. It was heated and cured for 1 hour to obtain a test piece. The test was based on JISK6854 and measured 180 degree peel strength at a tensile speed of 300 mm / mm. For the measurement, a small tabletop testing machine EZ-LX (manufactured by Shimadzu Corporation) was used.
The results are also shown in Table 1.

  An appearance test was performed on the obtained adhesive sheet. In the test, a release film (polyimide film with a silicone release agent) was bonded to both sides of the adhesive sheet so that the silicone release agent surface was in contact with the adhesive sheet, and the laminate was heated and cured in an oven at 180 ° C. The presence or absence of appearance abnormalities such as warpage, wrinkles, and peeling of the subsequent laminate was confirmed.

From Table 1, it can be understood that Example 1 has high peel strength. Examples 2 and 3 are examples in which the blending amount of the (C) radical generator was changed as compared with Example 1, but it can be understood that both have sufficient peel strength. Examples 4, 5, and 8 are examples in which the type of (B) the monomer and / or oligomer having an ethylenically unsaturated group was changed as compared with Example 1, but even in this case, sufficient peel strength was obtained. I can understand that In contrast, Comparative Example 1 using trimethylolpropane triacrylate having 3 ethylenically unsaturated groups as the component (B) has a remarkably low peel strength, and the component (B) contains ethylenically unsaturated groups. The comparative example 2 using the pentaerythritol tetraacrylate whose number is 4 also has remarkably low peel strength. These results suggest that the number of ethylenically unsaturated groups is 6 to 15 is effective.
Examples 6 and 9 are examples in which the type of the (C) radical generator was changed as compared with Example 1, but it can be understood that this case also has sufficient peel strength. On the other hand, Comparative Example 3 using 2,2′-azobis (2-methylpropionic acid) dimethyl, which is an azo compound that is also widely used as a radical generator, has a remarkably low peel strength. It is suggested that there is selectivity.
Example 7 is an example in which the rubber component having the (A) diene skeleton was changed as compared with Example 1, but it can be understood that the peel strength is sufficient even in this case.

[Examples 10 to 13]
Examples 10-13 and Example 2 are examples showing the relationship between the peel strength and haze of (D) an adhesive composition containing a tackifying resin and (D) an adhesive composition not containing a tackifying resin. .
The rubber component having a diene skeleton shown in Table 2, monomers and / or oligomers having an ethylenically unsaturated group, a radical generator and a tackifier resin are blended in the proportions (unit: parts) shown in Table 2. The adhesive sheet was obtained by the same method as in Examples 1-9.

The peel strength and haze of the adhesive sheets obtained in the same manner as in Examples 1 to 9 were examined. The results are also shown in Table 2. In Table 2, the composition, peel strength, and haze of the adhesive composition of Example 2 are also shown for comparison. The obtained adhesive sheet was subjected to haze measurement in accordance with JISK7136. For the measurement, a haze meter NDH4000 (manufactured by Nippon Denshoku Industries Co., Ltd.) was used.
From Table 2, it can be understood that the peel strength can be improved by including a tackifier resin.
In any of the Examples and Comparative Examples, no abnormal appearance such as warpage, wrinkles, and peeling was observed in the laminate composed of the cured adhesive sheet and release film.

<External appearance evaluation test of conventional example>
Bisphenol A type liquid epoxy resin (JER828: manufactured by Mitsubishi Chemical Corporation) 100 parts by mass, bisphenol A type solid epoxy resin (JER1009: manufactured by Mitsubishi Chemical Corporation) 100 parts by mass, acrylic copolymer 100 parts by mass, dicyandiamide 7 mass parts was mix | blended and the adhesive composition was prepared by stirring and mixing with the methyl ethyl ketone prepared separately. The obtained adhesive composition was degassed under reduced pressure. After defoaming, use an applicator on a release film (polyethylene terephthalate film with a silicone release agent) to apply and dry to a thickness of 100 μm after drying, and then release the release film to form an adhesive sheet. It was. Next, the above-described appearance test was performed on this adhesive sheet.
As a result, many warps and wrinkles were observed in the release film in the laminate.
From this, it can be confirmed that warp and wrinkle are generated in the epoxy resin composition, and it can be understood that the adhesive composition containing a rubber component having a diene skeleton is excellent.

  It can be understood that the adhesive composition of the present invention is excellent in adhesive force without causing appearance abnormality such as warpage and wrinkles.

Claims (5)

(A) a rubber component having a diene skeleton;
(B) a monomer and / or oligomer having 6 or more ethylenically unsaturated groups;
(C) a radical generator composed of an organic peroxide;
An adhesive composition comprising:   The adhesive composition according to claim 1, wherein the radical generator (C) comprising an organic peroxide has an aromatic group in one molecule and has a symmetrical structure.   The adhesive composition according to claim 1 or 2, further comprising (D) a tackifying resin.   The adhesive composition according to claim 3, wherein the haze of the adhesive composition containing the (D) tackifying resin is higher than the haze of the adhesive composition not containing the (D) tackifying resin.   The adhesive sheet using the adhesive composition as described in any one of Claims 1-4.