Anaerobic curing composition

Abstract

(a) a non-encapsulated liquid anaerobic curing monomer that forms a liquid phase; (b) a solid component dispersed as a solid phase within a liquid phase formed by a non-encapsulated liquid anaerobically curable monomer, The solid component has (meth)acrylate functionality and: (i) in the form of particles having a particle size in the range of about 80 μm to about 300 μm; (ii) a solid component having a melting point of about 50°C to about 90°C, and (c) an anaerobically curable composition comprising a curing component for curing the anaerobically curable composition in a liquid phase, which can be readily coated in a flowable form onto a substrate such as a threaded fastener or other part and then converted to a solid form of the anaerobically curable composition.

Description

[Technical Field]

[0001] This invention relates to anaerobic curable compositions. In particular, this invention relates to anaerobic curable compositions that are easily distributed but remain in place. [Background technology]

[0002] Anaerobic curable compositions are generally well known. See, for example, RDRich, "Anaerobic Adhesives," in "Handbook of Adhesive Technology," 29, pp. 467-479, edited by A. Pizzi and KLMittal, Marcel Dekker, Inc., New York (1994), and the references cited therein. Their uses are diverse, and the development of new applications continues.

[0003] Anaerobic adhesive systems are stable in the presence of oxygen but polymerize in the absence of oxygen. Polymerization is often initiated by the presence of free radicals generated from peroxy compounds. Anaerobic adhesive compositions are well known for their ability to remain in a liquid state, remaining non-polymerized in the presence of oxygen and curing into a solid state when oxygen is removed.

[0004] In many cases, anaerobic adhesive systems contain resin monomers terminated with polymerizable acrylate esters such as methacrylate, ethyl acrylate, and chloroacrylate esters derived according to known urethane chemistry [e.g., polyethylene glycol dimethacrylate and urethane acrylate (e.g., U.S. Patent No. 3,425,988 (Gorman))].

[0005] Other components typically found in anaerobic curing adhesive compositions include initiators such as organic hydroperoxides, e.g., cumene hydroperoxide and tert-butyl hydroperoxide; accelerators that increase the rate at which the composition cures; and stabilizers such as quinones or hydroquinones that are included to prevent premature polymerization of the adhesive due to the decomposition of peroxy compounds.

[0006] A desirable curing-inducing composition for inducing and promoting anaerobic curing may include one or more saccharins, toluidines such as N,N-diethyl-p-toluidine ("DE-pT") and N,N-dimethyl-o-toluidine ("DM-oT"), and acetylphenylhydrazine ("APH") containing maleic acid. See, for example, U.S. Patent No. 3,218,305 (Krieble), No. 4,180,640 (Melody), No. 4,287,330 (Rich), and No. 4,321,349 (Rich).

[0007] Saccharin and APH are used as standard curing accelerator components in anaerobic adhesive curing systems. In fact, many of the LOCTITE® brand anaerobic adhesive products currently available from Henkel Corporation use either saccharin alone or both saccharin and APH.

[0008] Anaerobic curing adhesive compositions also generally contain chelating agents, such as ethylenediaminetetraacetic acid (EDTA), which are used to sequester metal ions.

[0009] For handling purposes, anaerobic curing adhesive compositions are desirable to be easily dispensed but to remain in place after dispensing. One problem that arises is that, to facilitate dispensing, it is desirable to have the anaerobic curing adhesive composition in liquid form. A fluid liquid is suitable for dispensing. However, if the composition is liquid and fluid, it can be problematic for it to remain on the substrate to which it is dispensed. Thus, what is desirable for dispensing can be problematic during subsequent handling.

[0010] Anaerobic curable compositions may dry somewhat, for example, by evaporation (by drying or by drying for a certain period of time), but the material often remains wet and sticky. This can lead to contamination of anything that comes into contact with the coated article, and also to unwanted removal of the coated material. The latter concern is that it may remain insufficient to form the desired bond or seal, potentially compromising the integrity of the bond or seal subsequently formed by the anaerobic curable composition.

[0011] And of course, if the liquid carrier material itself is a liquid monomer, it will remain in liquid form until it hardens anaerobically. Therefore, even if these compositions are applied to a substrate and left to be exposed to anaerobic conditions, they will remain wet or at least tacky until they harden.

[0012] In the past, additional ingredients such as thickeners were added to the material, reducing its fluidity, but because the other ingredients are liquid, the overall composition remains somewhat fluid and / or viscous.

[0013] Tape products such as Loctite® and 249Quicktape® existed. These products consisted of a liquid anaerobic thread locker sandwiched between two non-reactive polyamide / polyurethane films.

[0014] Compositions suitable for threadlocking applications can be applied in a contact-drying form but possess anaerobic curing capabilities in a later stage. Additional components are often used to achieve this.

[0015] In some cases, a curing mechanism is used to achieve a contact-drying state. For example, a first curing mechanism may form a dry contact state to hold the composition in place on the article, while a second (anaerobic) curing mechanism is activated later to achieve curing, for example, to achieve thread locking.

[0016] For example, European Patent No. 0077659 (Thompson) describes a pre-coated polymerizable fluid for sealing and locking engineering parts. The composition has two mechanisms for curing, and two curing reactions occur. The first mechanism is UV light curing. An opacifier is dispersed in the fluid, making the fluid substantially opaque to radiation. After the fluid is applied to a part, it is exposed to UV radiation, where a coating is formed, forming a surface layer which is a dry, non-sticky outer layer. The fluid beneath the surface is unaffected by radiation (due to the opacifier) ​​and generally remains in a liquid state. When the parts are screwed into one another, the surface layer breaks, initiating a second polymerization (such as free radical polymerization), and a second curing reaction occurs. The second polymerization mechanism acts to lock the screws together. In Thompson, only the outer layer is formed in the first polymerization, and the rest of the composition remains liquid beneath the outer layer. Therefore, there is a risk that the outer layer may break during handling of the coated industrial parts, causing the liquid composition to leak out.

[0017] European Patent No. 0548369 (Usami) describes a pre-coated adhesive composition for application to the threaded contact surface of a screw. The composition comprises a photocurable binder in which a second curable composition is dispersed. The second curable composition comprises a microencapsulated reactive monomer / activator / initiator.

[0018] International patent application WO2004 / 024841A2 (Haller) describes a curable composition for application to threaded articles. The composition comprises a first curing mechanism component comprising (a) a (meth)acrylate-functional monomer component, (b) a (meth)acrylate-functional oligomer component, and (c) a photoinitiator component; and a second curing mechanism component comprising (ii)(e) an amine component and (f) an encapsulated epoxy resin component; and a dispersion of (iii) a thickening agent component. The photoinitiator component is suitable for irradiation of the composition and achieves a first curing over the depth of the composition applied to a threaded article, and a binder matrix is ​​formed using the second curing mechanism component dispersed through the matrix.

[0019] The English abstract of Chinese Patent Publication CN102558490 clearly discloses a hot-meltable prepolymer which is a urethane or polyurethane (meth)acrylate prepolymer having (meth)acryloyl-terminated groups. The melting point of the prepolymer is 50-80°C. An anaerobic adhesive is prepared from the hot-meltable prepolymer, a monomer containing at least one acrylic acid ester group or methacryloyl group, an accelerator, a stabilizer, and an initiator. A liquid monomer is mixed with the prepolymer to form a gel.

[0020] International patent application WO2017 / 068196 describes an anaerobic curable composition comprising an anaerobic curable component which is a combination of a solid resin component and a solid anaerobic curable monomer. A curing component is included for curing the anaerobic curable component. The composition is solid and has a melting point in the range of 30°C to 100°C. The composition is contact-dry and can be used to form products such as tapes, elongated filaments, gaskets, and patches. [Overview of the Initiative] [Problems that the invention aims to solve]

[0021] Despite the technical limitations, it would be desirable to provide alternative anaerobic curable compositions suitable for typical end uses, including threadlock applications.

Means for Solving the Problem

[0022] In one aspect, the present invention provides (a) an uncapsulated liquid anaerobic curable monomer that forms a liquid phase; (b) a solid component dispersed as a solid phase in the liquid phase formed by the uncapsulated liquid anaerobic curable monomer, where the solid component has a (meth)acrylate functional group and: (i) is particulate of particles having an average particle size in the range of about 80 μm to about 300 μm, (ii) has a melting point in the range of about 50 °C to about 90 °C, and (c) an anaerobic curable composition comprising a curing component for curing the anaerobic curable composition in the liquid phase.

[0023] The uncapsulated liquid anaerobic curable monomer may be present in an amount of about 10 wt% to about 50 wt%, for example, about 10 wt% to about 40 wt%, for example, about 10 wt% to about 30 wt% based on the total weight of the composition.

[0024] The solid component may be present in an amount of about 15 wt% to about 50 wt%, for example, about 30 wt% to about 45 wt% based on the total weight of the composition.

[0025] The solid component becomes particulate when dispersed in the liquid phase.

[0026] The solid component is reactive and participates in the anaerobic curing reaction.

[0027] The curing component / initiator is present in an amount of about 4 wt% to about 6 wt% based on the total weight of the composition.

[0028] The anaerobic curable composition of the present invention may further contain about 10% to about 30% by weight of propoxylated bisphenol A fumarate polyester, based on the total weight of the composition dissolved in the liquid phase. This component imparts a desirable viscosity when the composition of the present invention is in paste form and gives it desirable physical properties when it is in solid form. Other viscosity modifiers, such as acrylic resins (available from Lucite International under the trade name Elvacite®), can be used. Silica can also be used. However, the use of propoxylated bisphenol A fumarate polyester is preferred. Overall, the amount of viscosity modifier (including propoxylated bisphenol A fumarate polyester) is typically about 10% to about 30% by weight, based on the total weight of the composition dissolved in the liquid phase.

[0029] The solid component preferably includes a solid anaerobic curable monomer having a melting point of about 50°C to about 90°C.

[0030] Optionally, the solid component may include a solid resin having a melting point of approximately 50°C to 90°C.

[0031] The solid resin has (meth)acrylate functional groups.

[0032] In one embodiment, the composition of the present invention is a fluid paste having a viscosity of approximately 40,000 mPa·s to 500,000 mPa·s, for example, approximately 60,000 to approximately 180,000 mPa·s, or for example, approximately 75,000 to approximately 125,000 mPa·s, as measured by ASTM D4287 at 25°C.

[0033] The anaerobic curable composition of the present invention may be provided in solid form, which is formed by heating the composition according to any prior claim such that the solid component melts into a molten form and mixes with an unencapsulated liquid anaerobic curable monomer to form a mixture, and by passively or actively cooling the mixture to a solid state.

[0034] The present invention also relates to a substrate to which a paste-like anaerobic curable composition of the present invention is applied.

[0035] The present invention also relates to a substrate to which a solid anaerobic curable composition is applied.

[0036] The present invention also provides a method for formulating an anaerobic curable composition. Anaerobic curable compositions, (a) Non-encapsulated liquid anaerobic curable monomers that form a liquid phase; (b) A solid component dispersed as a solid phase within a liquid phase formed by an unencapsulated liquid anaerobic curable monomer, The solid component has (meth)acrylate functional groups, and: (i) The particles are particulate and have a particle size in the range of approximately 80 μm to approximately 300 μm. (ii) Solid components having a melting point of approximately 50°C to approximately 90°C, (c) Containing a curing component for curing an anaerobic curable composition in the liquid phase, The method includes a step of dispersing solid components in a liquid phase.

[0037] In the method of the present invention, it is desirable to add the curing component after the step of dispersing the solid component in the liquid phase.

[0038] Preferably, the hardening component is added in a microencapsulated form.

[0039] The present invention also provides a method for applying the anaerobic curable composition of the present invention to a substrate. (a) Formulate the composition as a fluid composition, (b) Apply the fluid composition to the substrate, (c) The solid component melts into a molten form and mixes with the non-encapsulated liquid anaerobic curable monomer to form a mixture. (d) A step of passively or actively cooling the mixture onto a substrate until it becomes solid.

[0040] The present invention also relates to an assembly comprising a first substrate and a second substrate bonded together using any composition described in any one of claims 1 to 9.

[0041] The composition of the present invention may take two different forms.

[0042] At temperatures below the melting point of the solid components, for example below 50°C, and therefore at ambient temperature, the composition forms a fluid paste with a viscosity of approximately 40,000 mPa·s to 500,000 mPa·s, for example approximately 60,000 to 180,000 mPa·s, or for example approximately 75,000 to 125,000 mPa·s, at 25°C, as measured by ASTM D4287. The solid components remain solid and dispersed in the liquid phase. In this initial paste-like state formed by the solid dispersed in the liquid phase, the composition hardens anaerobically but retains fluidity. At temperatures below the melting point of the solid components, the solid components are insoluble in the liquid phase.

[0043] When the composition of the present invention is heated to a temperature above the melting point of the solid component, for example, above 50°C, and therefore far above the ambient temperature, the solid component melts into a liquid and moves into the liquid phase, forming a combined single phase. In its molten state, the solid component is miscible with the liquid phase. When the mixed materials are cooled below the melting point of the solid component, the composition does not return to a fluid paste-like state, but instead becomes a solid. For example, it may be a waxy solid.

[0044] In this second form, the solid component and the unencapsulated liquid anaerobic curable monomer are no longer in separate phases, but instead reside in a single solid phase. The composition remains uncured but is still anaerobic curable and solid.

[0045] The solid components, upon melting, become compatible with the liquid phase and mix well. They do not separate from the liquid phase.

[0046] As the composition cools, it changes from a paste-like state (before heating) to a solid state (to produce a homogeneous solid product).

[0047] The solid state can be particulate, such as a powder. Since the powder is essentially dry, the particles do not stick together or aggregate.

[0048] The solid components can be a suitable combination of materials.

[0049] The solid components are curable / reactive. The solid components participate in anaerobic curing reactions and are themselves anaerobic curable.

[0050] Therefore, all reactive components of the composition, whether liquid or solid, can participate in the anaerobic curing reaction.

[0051] In this invention, the particle size is determined by laser diffraction in accordance with ASTM E2651-13.

[0052] Melting and resolidification can be measured by DSC (Differential Scanning Calorimetry).

[0053] The present invention, disclosed herein, relates to a novel anaerobic curable composition having a novel physical form. This is an anaerobic adhesive composition that can be used to achieve a dry-touch solid coating for pre-coated applications. The anaerobic curable composition comprises a curable solid reactive component (optionally containing a non-reactive component) suspended and mixed in a liquid reactive monomer to form a paste. At the melting point of the solid, as the solid melts, the paste is converted to a liquid, and then, upon cooling, forms a solid material. When the composition is heated and the solid material melts, the solid and liquid materials mix and do not revert to a paste.

[0054] This new form of anaerobic product can be manufactured, handled, and dispensed as a high-viscosity liquid / paste, but readily converted to a solid material by applying heat. It is designed to address handling, processing, and stability issues.

[0055] And of course, it is fluid and anaerobic curable in its first form, and then solid, but is anaerobic curable in its solid form. Furthermore, its viscosity in its first form is 75,000 to 500,000 mPa·s (or actually within other viscosity ranges disclosed herein) at 25°C, meaning it can be dispensed onto a substrate in a curable and fluid form. This allows for a variety of applications. When the substrate is heated, the composition can be converted into a solid or cured form. The solid form is still anaerobic curable. The solid form has the advantage of being non-fluid, so the anaerobic curable composition is retained on the substrate. The initial fluid composition can be converted into a solid composition, and therefore the fluid composition can be considered a plastisol.

[0056] For example, an anaerobic curable composition can be easily coated onto a substrate such as a threaded fastener or other component in its fluid form and then converted into a solid anaerobic curable composition. Once solidified, the risk of handling problems associated with anaerobic curable compositions is eliminated because the material is fluid / liquid. Therefore, equipment for handling substrates and other substrates that come into contact with the coated substrate is less likely to be contaminated by anaerobic curable compositions that move from the equipment and / or other substrates through physical contact.

[0057] The inventors' objective was to develop an anaerobic curable composition, such as an anaerobic adhesive, that can be applied to a substrate such as a threaded fastener with a rapid drying contact time, and in particular to enable rapid turnaround of the substrate by eliminating the drying time.

[0058] This is of interest to products such as substrates coated with an anaerobic curable composition for later use. That is, since they are coated with the composition of the present invention, they are pre-applied with the anaerobic curable composition in situ (for later use, usually off-site).

[0059] The market for pre-applied anaerobic products is currently offered by water-based and solvent-based products. These are applied using large-footprint equipment in specialized coating centers. For example, Henkel's Dri-Loc® products are water-based anaerobic adhesive technology. Some of these conventional technology compositions are two-part or three-part formulations that are mixed at the application site and applied to a large number of threaded fasteners on specialized equipment. The water (or solvent) content of the formulation is then removed over several hours using a large drying oven, and the threaded bolts with the adhesive pre-applied are supplied.

[0060] The present invention provides an anaerobic adhesive containing a solid component that melts at a moderately low temperature (e.g., 55-80°C), can be applied to threaded portions in its molten state, and rapidly cools to leave a solid coating on the part. This eliminates the need for large drying ovens or specialized coating centers, and allows for the provision of pre-applied solutions for, for example, small-scale users.

[0061] The paste-like consistency at room temperature makes the composition easy to manufacture and handle, including in bottling / packaging.

[0062] Furthermore, the composition of the present invention may also be in solid form in a container that is removed for later use rather than being applied beforehand.

[0063] The paste form can be dispensed as a paste from a dispensing pack or cartridge pack.

[0064] As described herein, the composition can be converted into a solid form in a pre-coated state, and as a result, a product manufactured at a first location for use at a second location may have a solid composition pre-coated onto a substrate. Alternatively, the conversion to a solid state may occur at the site of distribution / application to the substrate.

[0065] One advantage of the present invention is that the composition is formulated as a one-part composition, yet is still anaerobic curable. When the composition of the present invention was exposed to a temperature of 22°C under ASTM:D1337, storage stability was achieved for at least 12 months. Some existing anaerobic curable compositions are formulated as at least two-part compositions because they lack storage stability or cure prematurely when formulated as a one-part composition.

[0066] Another advantage of the present invention is that the composition dries quickly, eliminating the need to dry the oven or extend the drying time, as is the case with water-based or solvent-based compositions.

[0067] Therefore, the compositions of the present invention are very suitable for small-scale operations.

[0068] The compositions of the present invention allow for unique combinations of forms. For example, the compositions of the present invention can be sequentially converted from paste (solid particles dispersed in a liquid phase) to liquid (solid particles melt and mix with the liquid phase) to solid (the composition solidifies upon cooling).

[0069] The unencapsulated liquid anaerobic curable monomer may be any liquid methacrylate or acrylate, or a functionalized monomer. Any combination of unencapsulated liquid anaerobic curable monomers can be used.

[0070] The solid components are curable / reactive.

[0071] The solid components are involved in the anaerobic curing reaction and are themselves anaerobic curable.

[0072] However, the other components of the composition may be liquid or solid, and may be non-reactive, and they may not be involved in the anaerobic curing reaction.

[0073] The solid component may be a solid anaerobic curable monomer, such as 2-methacrylateoxyethylphenylurethane-"2-MAPU".

[0074] The solid component may be a solid methacrylate-functionalized resin, such as a long-chain meth(acrylate) polyurethane with a molecular weight exceeding 2000 g / mol.

[0075] The solid component may be any other solid powder material, as long as it satisfies the parameters described above as a whole.

[0076] Preferably, the solid component does not contain polyethylene glycol, such as polyethylene glycol particles, which are inert in the anaerobic curing reaction.

[0077] It will be understood that the solid components can be any combination of the above materials, as long as the overall parameters are met.

[0078] The composition of the present invention has many end-use applications, similar to conventional anaerobic curable compositions.

[0079] The compositions of the present invention have applications in metal-to-metal bonding, such as thread compositions for fastening nuts and bolts, or for fastening female threads to male threads. The products harden when trapped between tightly adhering (metal, etc.) surfaces in an air-free state. They protect threads from rust and corrosion and prevent loosening due to impact and vibration.

[0080] The compositions of the present invention are suitable for storage and handling, such as shipping, even when applied to parts. This storage or handling does not adversely affect the integrity of the composition, for example, when it exists as a coating.

[0081] Machining surfaces such as flanges have historically been sealed, for example, in the automotive industry, by applying a liquid anaerobic curable composition to one of the surfaces. Then, two surfaces, such as flange surfaces, are assembled, and the product cures in the absence of oxygen, creating a gasket and seal.

[0082] The composition of the present invention can be applied to such a mating surface in either liquid or paste form. For example, it can be applied in paste form and then heated to convert it into a solid form.

[0083] Desirable curing-inducing components for inducing and accelerating anaerobic curing may include one or more saccharins, N,N-diethyl-p-toluidine ("DE-pT") and N,N-dimethyl-o-toluidine ("DM-oT"), and acetylphenylhydrazine ("APH") containing maleic acid. See, for example, U.S. Patent Nos. 3,218,305 (Krieble), 4,180,640 (Melody), and 4,287,330 (Rich).

[0084] It may contain stabilizers such as quinone or hydroquinone.

[0085] The unencapsulated liquid anaerobic curable monomer can be selected from any suitable anaerobic curable material (or any combination of materials) including those listed below. Preferably, it is a liquid.

[0086] Anaerobic curable compositions may have anaerobic curable components based on appropriate (meth)acrylate components.

[0087] One or more suitable (meth)acrylate components are given by the formula: H2C=CGCO2R 8 (In the formula, G may be hydrogen, a halogen, or an alkyl group having 1 to about 4 carbon atoms, R 8 The group may be selected from alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkaryl, aralkyl, or aryl groups having 1 to about 16 carbon atoms, and these groups may optionally be substituted or blocked in some cases with silane, silicon, oxygen, halogen, carbonyl, hydroxyl, ester, carboxylic acid, urea, urethane, polyurethane, carbonate, amine, amide, sulfur, sulfonate, and sulfone.) The group may be selected from (meth)acrylate monomers having

[0088] One or more suitable (meth)acrylate monomers, for example, but not limited to: Polyethylene glycol di(meth)acrylate, tetrahydrofuran(meth)acrylate and di(meth)acrylate, hydroxypropyl(meth)acrylate ("HPMA"), hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate ("TMPTMA"), diethylene glycol dimethacrylate, triethylene glycol dimethacrylate ("TRIEGMA"), tetraethylene glycol dimethacrylate, dipropylene diglycol dimethacrylate, di(pentamethylene glycol) dimethacrylate, tetraethylene diglycol dimethacrylate The selection may be made from polyfunctional (meth)acrylate monomers such as bisphenol-A-mono and di(meth)acrylates, including acrylate, diglycerol tetramethacrylate, tetramethylene dimethacrylate, ethylene dimethacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, and ethoxylated bisphenol-A (meth)acrylate ("EBIPMA"), and bisphenol-F-mono and di(meth)acrylates, including ethoxylated bisphenol-F (meth)acrylate, and other bifunctional or trifunctional (meth)acrylates.

[0089] For example, the anaerobic curable component may contain the following bisphenol A dimethacrylates (as anaerobic curable monomers) having a melting point of approximately 72-74°C.

[0090] [ka]

[0091] Further (meth)acrylate monomers suitable for use herein include silicone (meth)acrylate moieties ("SiMA") as taught and claimed by U.S. Patent No. 5,605,999 (Chu), the disclosure of which is expressly incorporated herein by reference.

[0092] Other suitable monomers may be selected from polyacrylate esters represented by the following formula.

[0093] [ka] During the ceremony, R 4 is a group selected from hydrogen, halogens, or alkyls having 1 to about 4 carbon atoms; q is an integer equal to at least 1, preferably 1 to about 4; and X is an organic group containing at least 2 carbon atoms with a total bond capacity of q+1. Regarding the upper limit of the number of carbon atoms in X, there are monomers that can function at essentially any value. However, in practice, the general upper limit is about 50 carbon atoms, preferably 30, and most preferably about 20.

[0094] For example, X may be an organic group as shown in the following formula.

[0095] [ka] During the ceremony, Y 1 and Y 2 Each of them is an organic group such as a hydrocarbon group containing at least two carbon atoms, preferably two to about ten carbon atoms, and Z is an organic group, preferably a hydrocarbon group containing at least one carbon atom, preferably two to about ten carbon atoms.

[0096] Other monomers may be selected from reaction products of di- or tri-alkylolamines (e.g., ethanolamine or propanolamine) with acrylic acid, as disclosed in French Patent No. 1,581,361.

[0097] Suitable oligomers having (meth)acrylate functional groups may also be used. Examples of such (meth)acrylate-functionalized oligomers include those having the following general formula:

[0098] [ka] In the formula, R 5 This includes hydrogen, alkyl groups having 1 to about 4 carbon atoms, hydroxyalkyl groups having 1 to about 4 carbon atoms, or

[0099] [ka] It is a base selected from, R 4 R is a group selected from hydrogen, halogens, or alkyl groups having 1 to about 4 carbon atoms; 6 is hydrogen, hydroxyl or

[0100] [ka] And, m is an integer at least equal to 1, e.g., 1 to about 15 or greater, preferably 1 to about 8; n is an integer at least equal to 1, e.g., 1 to about 40 or greater, preferably about 2 to about 10; and p is 0 or 1.

[0101] Typical examples of acrylic acid ester oligomers corresponding to the above general formula include di-, tri-, and tetraethylene glycol dimethacrylate; di(pentamethylene glycol) dimethacrylate; tetraethylene glycol diacrylate; tetraethylene glycol di(chloroacrylate); diglycerol diacrylate; diglycerol tetramethacrylate; butylene glycol dimethacrylate; neopentyl glycol diacrylate; and trimethylolpropane triacrylate.

[0102] Di- and other polyacrylate esters, particularly those described in the previous paragraph, are preferred, but monofunctional acrylate esters (esters containing one acrylate group) can also be used.

[0103] Suitable compounds can be selected from cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, t-butylaminoethyl methacrylate, cyanoethyl acrylate, and chloroethyl methacrylate.

[0104] Another useful class of materials are the reaction products of (meth)acrylate-functionalized, hydroxyl- or amino-containing materials with a suitable ratio of polyisocyanates to convert all isocyanate groups to urethane or ureido groups, respectively.

[0105] The (meth)acrylate urethanes or urea esters so formed may contain hydroxy or amino functional groups in their non-acrylate portions. Suitable (meth)acrylate esters for use are of the formula

[0106]

Chemical formula

[0107]

Chemical formula

[0108] These groups, upon suitable reaction with polyisocyanates, produce monomers of the following general formula.

[0109]

Chemical formula

[0110] Depending on the properties of B, these (meth)acrylate esters having urea or urethane bonds may have molecular weights that are oligomer class (e.g., about 1,000 g / mol to about 5,000 g / mol) or polymer class (e.g., about 5,000 g / mol or more).

[0111] Of course, these (meth)acrylate monomers may also be used.

[0112] Preferably, the anaerobic curing component includes at least one acrylate or methacrylate ester group.

[0113] Preferably, the anaerobic curing component is selected from at least one of the following: epoxy (meth)acrylate, urethane (meth)acrylate, urethane di(meth)acrylate, alkyl (meth)acrylate, stearyl (meth)acrylate, isocyanurate (meth)acrylate, bisphenol-A-(meth)acrylate, ethoxylated bisphenol-A-(meth)acrylate, bisphenol-F-(meth)acrylate, ethoxylated bisphenol-F-(meth)acrylate, bisphenol-A di(meth)acrylate, ethoxylated bisphenol-A-di(meth)acrylate, bisphenol-F-di(meth)acrylate, ethoxylated bisphenol-F-di(meth)acrylate, etc.

[0114] The compositions of the present invention may also contain other conventional components such as free radical initiators, free radical promoters, free radical generation inhibitors, and metal catalysts such as iron and copper.

[0115] Many well-known initiators of free radical polymerization, including hydroperoxides such as CHP, paramentane hydroperoxide, t-butyl hydroperoxide ("TBH"), and t-butyl perbenzoate, can be incorporated into the compositions of the present invention. Other peroxides include benzoyl peroxide, dibenzoyl peroxide, 1,3-bis(t-butylperoxyisopropyl)benzene, diacetyl peroxide, 4,4-bis(t-butylperoxy)butyl valerate, p-chlorobenzoyl peroxide, cumene hydroperoxide, t-butylcumyl peroxide, t-butyl perbenzoate, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane, 2,5-dimethyl-2,5-di-t-butylperoxyhexa-3-yne, 4-methyl-2,2-di-t-butylperoxypentane, and combinations thereof.

[0116] Such peroxide compounds are typically used in the present invention in a range of about 0.1 to about 10 weight percent based on the total weight of the composition, and preferably in a range of about 1 to about 5 weight percent based on the total weight of the composition.

[0117] If necessary, the initiator component can be encapsulated. For example, the initiator component may be an encapsulated peroxide, such as encapsulated benzoyl peroxide ("BPO").

[0118] For example, using the composition of the present invention, an initiator component, which may be an encapsulation material such as a microencapsulated material, or an encapsulated peroxide such as encapsulated benzoyl peroxide, can be dispersed into a first paste without heating. This is advantageous because the half-life of the microencapsulated peroxide initiator BPO is 1 hour at 92°C.

[0119] In paste form, microcaps and other powdered solids disperse easily, without settling, and are more stable.

[0120] The composition of the present invention may further comprise a thickener and / or a filler.

[0121] As described above, it will be understood that the compositions of the present invention may contain non-reactive species, including resins. Such components do not participate in the anaerobic curing reaction; they are non-reactive. However, such components may become part of the cured product incorporated into the curing of other components during their curing. Examples of such non-reactive species include fumed silica, polyethylene, PTFE, mica, polyamide wax, titanium dioxide, and barium sulfate. [Brief explanation of the drawing]

[0122] Embodiments of the present invention will be described only by reference to the accompanying drawings. [Figure 1] Figure 1 is a graph showing the 24-hour curing strength of the Example 2 composition in various threaded fasteners. [Modes for carrying out the invention]

[0123] <Detailed explanation> Embodiments of the present invention are described by reference to the following, only as examples. [Examples]

[0124] <Example 1 - Paste formulation 4158-045> [Table 1]

[0125] LID6882 is a functional solid resin, a bifunctional methacrylate PU resin derived from a semi-crystalline polyol. When pulverized, the average particle size is less than 100 μm.

[0126] The compositions in the table above are combined with the solid monomer 2-methacrylateoxyethylphenyl urethane.

[0127] <Example 2: Paste formulation 4158-063> [Table 2]

[0128] LID 6882 is a functional solid resin, a bifunctional methacrylate PU resin derived from a semi-crystalline polyol. When pulverized, the average particle size is less than 100 μm.

[0129] The compositions in the table above are combined with the solid monomer 2-methacrylateoxyethylphenyl urethane.

[0130] Figure 1 is a graph showing the 24-hour curing strength of the composition in this example on various M10 threaded fasteners. The composition in this example was applied to an M10 bolt heated to 90°C. The bolts used were made of stainless steel, zinc phosphate, zinc dichromate coated steel, brass, and black oxide coated mild steel. The paste was applied to the heated part, where it melted and then cooled to form a solid, waxy coating. After combining the mating nut with the coated part and curing the unassembled assembly for 24 hours, the strength required to disassemble the assembled nut and bolt was estimated using a torque measuring device with ASTM D5649.

[0131] <Example 3: Paste formulation 4158-064> [Table 2]

[0132] Non-reactive solid powder: Polyethylene glycol with an average molecular weight of 8000 g / mol. The compositions in the table above are combined with the solid monomer 2-methacrylateoxyethylphenyl urethane.

[0133] When used in reference to the present invention, the terms “contains / includes” and “have / includes” are used to identify the presence of a described feature, integer, step, or component, but do not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.

[0134] For clarity, certain features of the present invention described in the context of separate embodiments may be provided in combination in a single embodiment. Conversely, for brevity, various features of the present invention described in the context of a single embodiment may also be provided separately or in any suitable subcombination.

Claims

1. (a) A liquid phase containing an unencapsulated liquid anaerobic curable monomer in an amount of 10% to 50% by weight based on the total weight of the composition; (b) A solid component dispersed in the liquid phase, The solid component has (meth)acrylate functional groups, and: (i) The particulate matter consists of particles with an average particle size in the range of up to 300 μm, (ii) A solid phase containing a solid component having a melting point of 50°C to 90°C in an amount of 15% to 50% by weight based on the total weight of the composition, and (c) An anaerobic curable composition for forming a solid coating comprising a curing component for curing an unencapsulated liquid anaerobic curable monomer and a (meth)acrylate-functionalized solid component in the liquid phase, The composition is Based on the total weight of the composition dissolved in the liquid phase, it further contains 10% to 30% by weight of propoxylated bisphenol A fumarate polyester. An anaerobic curable composition that is a fluid paste having a viscosity of 40,000 mPa·s to 500,000 mPa·s at 25°C, as measured by ASTM D4287.

2. The anaerobic curable composition according to claim 1, wherein the curing component is present in an amount of 4% to 6% by weight based on the total weight of the composition.

3. The anaerobic curable composition according to claim 1 or 2, wherein the solid component comprises a solid anaerobic curable monomer having a melting point of 50°C to 90°C.

4. The anaerobic curable composition according to any one of claims 1 to 3, wherein the solid component comprises a solid resin having a melting point of 50°C to 90°C.

5. The anaerobic curable composition according to any one of claims 1 to 4, wherein the composition has a viscosity of 60,000 to 180,000 mPa·s at 25°C, as measured by ASTM D4287.

6. A substrate to which the anaerobic curable composition according to any one of claims 1 to 5 has been applied.

7. A method for formulating an anaerobic curable composition for forming a solid coating, Anaerobic curable compositions, (a) A liquid phase containing an unencapsulated liquid anaerobic curable monomer in an amount of 10% to 50% by weight based on the total weight of the composition; (b) A solid component dispersed in the liquid phase, The solid component has (meth)acrylate functional groups, and: (i) The particulate matter consists of particles with a particle size in the range of up to 300 μm, (ii) A solid phase containing a solid component having a melting point of 50°C to 90°C in an amount of 15% to 50% by weight based on the total weight of the composition, and (c) comprising a curing component for curing unencapsulated liquid anaerobic curable monomers and (meth)acrylate-functionalized solid components in the liquid phase, The composition is Based on the total weight of the composition dissolved in the liquid phase, it further contains 10% to 30% by weight of propoxylated bisphenol A fumarate polyester. As measured by ASTM D4287, it is a fluid paste having a viscosity of 40,000 mPa·s to 500,000 mPa·s at 25°C. A method comprising the step of dispersing a solid component in a liquid phase.

8. The method according to claim 7, further comprising the step of dispersing a solid component in a liquid phase, followed by the addition of a curing agent component.

9. The method according to claim 8, wherein the hardening component is added in a microencapsulated form.

10. A method for applying an anaerobic curable composition according to any one of claims 1 to 5 to a substrate, (a) Formulate the composition as a fluid composition, (b) Apply the fluid composition to the substrate, (c) The solid component melts into a molten form and mixes with the non-encapsulated liquid anaerobic curable monomer to form a mixture. (d) A method comprising the step of passively or actively cooling a mixture onto a substrate into a solid state.

11. An assembly comprising a first substrate and a second substrate bonded together using the composition according to any one of claims 1 to 5.

Images