Development and manufacturing process of powdered additive for its use in coatings or substrates to repel, reduce and control insects

Abstract

The innovation herein refers to a formulation of powdered additive for its incorporation in coatings or substrates to repel, reduce and control insects, consisting of at least one active insecticide ingredient, or a combination of two or more active insecticide ingredients with high-performance double microencapsulation, and alternatively with least one reflective and/or photoluminescent, high-luminosity micro-encapsulated pigment, generating a dual insecticide effect, preventing insects from creating immunity to insecticides, which stops mutation, as completely different insecticides are delivered overtime. It is also very effective during night and day, over long period of time (years), with an efficient manufacturing process.

Claims

1. A formulation of powdered additive for incorporating in coatings or substrates to repel, reduce, or control insects comprising: A) 0.01-1.5 g microencapsulated deltamethrin, B) 1-10 g boric acid, C) 1-8.5 g microencapsulated cypermethrin, D) 1-8 g calcium oxide, E) a photoluminescent microencapsulated pigment, and F) a reflective microencapsulated pigment.

Description

INVENTION DESCRIPTION

(1) The powdered additive formulation for its incorporation in coatings or substrates to repel, reduce and control insects consists of at least one active insecticide ingredient, or a mixture of two or more active insecticide ingredients with high-efficiency double microencapsulation and, alternatively, at least one reflecting and/or photoluminescent micro-encapsulated pigment with high luminosity, generating a dual insecticide effect, very effective during day and night.

(2) In the preferred mode of the invention, such active insecticide ingredients are selected from a group formed by organochloride, organophosphate, carbamate, pyrethrin insecticides, biorational pesticides, among others: as well as insecticides made of plant extracts.

(3) The basic formula of the powdered additive for its incorporation in coatings or substrates to repel, reduce and control insects without luminescent pigments can control the insect population without attracting lucifuge insects with positive phototaxis, where due to the double microencapsulation, a more stable and lasting effect is achieved, and the combination of active ingredients acting simultaneously achieve the expected results.

(4) In the case of the formulation that includes at least one reflecting and/or photoluminescent micro-encapsulated pigment, high luminosity is generated in the formulation, with a dual effect that attracts a strong attraction of insects when the product is applied, for example, on paint, on any kind of surface. Due to the luminosity derived from the mixture of the aforementioned components, it works with high efficiency and efficacy, during day and night, thanks to the high-luminosity pigments that have the main purpose of shining in the dark by charging on luminous and/or thermal power through natural or artificial sources; that is to say, with the attraction effect for lucifuge insects with positive phototaxis, it works 24 hours a day, in comparison to other traditional products that only work for 8 hours.

(5) Some of the insects attracted by the luminescent component of the powdered additive formulation defined by at least one insecticide component, or a mixture of two or more insecticide components, with double high-efficacy microencapsulation, and alternatively with at least one reflecting and/or photoluminescent micro-encapsulated, high-luminosity pigments, include moths, flies, mosquitos, and many other lucifuge insects with positive phototaxis, which means they are naturally attracted to it.

(6) Other insects such as cockroaches, insect maggots, have negative phototaxis, which means they will not be attracted by the luminosity of the formulation, but they will be repelled or killed by it, due to the insecticide components.

(7) The microencapsulation of at least one active insecticide ingredient, or the mixture of two or more active insecticide ingredients, and of at least one reflecting and/or photoluminescent, high-luminosity micro-encapsulated pigment, are preferably done separately.

(8) In the preferred mode of the invention, the microencapsulation of at least one insecticide component, or a mixture of two or more insecticide components and at least one reflective and/or photoluminescent, high-luminosity micro-encapsulated pigment, is performed through a microencapsulation processes by coacervation, or through an ionic microencapsulation process.

(9) The microencapsulation comprises a rather heterogeneous set of procedures, and it applies diverse techniques and materials. There are three main stages to consider: The core The coating material Characterization

(10) In microencapsulation, the core material is formed by solid particles or small liquid drops, and their integration is performed by agitation, using adjuvants, stabilizers, antioxidants and diluents.

(11) The coating materials used must be compatible with the final product to apply; for example, if the core of water steam action is to be protected, or if the coating must resist the extracting action of water, it must be hydrophobic, to provide a proper protecting barrier.

(12) In the characterization, the core material is released under certain conditions that promote releasing, these conditions do not depend on moisture or pH, or pressure and mechanical strength applied on them.

(13) The proposed micro-capsules to be designed were developed considering the following:

(14) a.nucleation

(15) B.shell hardness

(16) c.dispersibility

(17) d.pH

(18) Variable Identification

(19) The micro-capsules release process involves the following:

(20) 1.minimum percentage concentration

(21) 2.concentration of active ingredient to release

(22) 3.medium pH

(23) 4.type of paint to use

(24) 5.application temperature

(25) 6.ambient temperature

(26) 7.roughness of surface to paint

(27) 8.insects to eliminate

(28) 9.endemic insects

(29) 10.invasive insects

(30) 11.plagues

(31) 12.film thickness

(32) Microencapsulation Processes Used

(33) 1.Polymeric microencapsulation

(34) 2.Microencapsulation by coacervation

(35) 3.Ionic microencapsulation

(36) With the use of these microencapsulation processes, several types of micro-capsules are obtained, with different characteristics, offering several functions regarding their releasing behavior.

(37) 1. Polymeric Microencapsulation

(38) The micro-capsule has a relatively simple morphological structure, it is formed by two clearly differentiated elements, the active core and a thin polymeric shell covering the core. Due to the polymer characteristics, a gradual release of these active ingredients is achieved, which are integrated according to the specific application requirements of the substrate into which the micro-capsules will be deposited.

(39) The core consists of liquid substances (mineral oil), which contain the active insecticide ingredients.

(40) The micro-capsule formation is a complex chemical-physical process through which a suspension is obtained with micro-capsules that Rank from one to several hundred micrometers. The gradual and controlled release of the micro-encapsulated actives is obtained thanks to the nature of the coating polymer.

(41) The key element of the additive formulation is the insecticide polymeric micro-capsule, that can also contain other components, such as a photoluminescent, high-luminosity pigment, whose main charge is calcium carbonate, the polymer is a vinyl, and the insecticides vary according to the type of vector, place of application, strategy to follow to control the plague and the applicable regulations.

(42) In any case, it is always insecticide and acaricide active principles of wide action spectrum frequently used in insecticide formulations; thus, pyrethroids are used when immediate control is necessary, as well as a significant shock effect, without long residuality. In case prolonged efficacy is necessary, instead of an immediate effect, organophosphates are used. In all cases, paint is added a crawling-insect/cockroaches-repelling insecticide.

(43) MICRO-CAPSULE CHEMICAL DEVELOPMENT. A polymer is a chemical substance formed by macromolecules, usually of organic nature, that were formed due to the binding of repeating smaller molecules called monomers.

(44) Thus, obtaining a formula with gradual release, which is also effective, depends on the ratio in which these two monomers are included when the resulting polymer is produced, as well as other factors inherent to the manufacturing process, such as the moment in which the insecticide actives are incorporated, and the temperatures reached.

(45) Life stages of paint (manufacturingliquid paint) (applicationliquid/dry paint) of different kind of polymer. First, during the manufacturing stage in which the polymer is scattered in water, the hardness of its shell is low, when it is applied and it starts to dry, the hardness increases. In the case of hard polymers, the microcapsule would be so rigid that it would not allow the active ingredient to be released, unlike the soft polymers, with which the release would be so fast that the efficacy persistency would be too low. In the case of the polymer used in this invention, there is a proper balance between hardness and flexibility, achieving a high efficacy persistency through the controlled release of active ingredients.

(46) Other steps that are just as important are the addition of loads and pigments, and the load of active insecticide and stabilizing ingredients, required to dorm the insecticide polymeric micro-capsule protecting the actives in an acid medium (pH 4-5) to maintain the chemical stability of the ingredients for a long time, as well as all the insecticide properties.

(47) A double shell can be provided for an active ingredient, for a longer release, controlling this characteristics overtime.

Example 1 Powdered Insecticide Polymer Microcapsules Components

(48) Melamine Chitosan Glutaraldehyde Calcium chloride Lauryl ether sulfate Acetic acid Powdered/mineral oil insecticides Propylene glycol Distilled water

(49) TABLE-US-00001 FORMULATION PRODUCT % Melamine 1-5 Chitosan 1-3 Glutaraldehyde 5-20 Calcium chloride 1-10 Lauryl Ether Sulphate 1-10 Acetic Acid 0.1-0.5 Insecticide Oil 1-15 Propylene Glycol 10-30
Methodology
1.Weight the melamine and the active ingredient (insecticide with mineral oil), and the propylene glycol;
2.In a reactor, add the melamine, the active ingredient and the propylene glycol homogeneously for around 30 minutes, and then add previously dispersed chitosan in a solution with acetic acid;
3.Stir vigorously until a paste id formed, and add a sodium hydroxide solution, lauryl ether sulfate, and a little glutaraldehyde;
4.Stir for around 30 minutes, and add the rest of the glutaraldehyde, followed by the calcium chloride;
5.Stir the resulting mix for 40 minutes, and set for filtration. Decant of necessary. The filter paper must be washed three times with distilled water, and the resulting product is set aside;
6.Dry the ambient or centrifuge or dry by heat at 30 C. in a stove for 24 hr.
7.For convenience purposes, use the material scattered in aqueous solution (slurry) or use the wet powder
8.Pack and save in sealed containers, away from the light
2. Micro-Encapsulation by Coacervation

(50) Among the microencapsulation methods, we can find the stirring or complex coacervation microencapsulation, which is appropriate for the liquid active ingredients processing, as a shell-forming polysaccharide is used as reticulation matrix, followed by the addition of other agents such as chelating agents, sequestrants, colorants and preservatives, that make the system so complex that it would have to be chemically fractioned to understand its release mechanism in the dispersed system in question, on the other hand, it is considered that the shell formed must be hard and friable at the same time, in order to release the encapsulated materials, and to make the process reversible.

(51) The coacervation process is a partial dehydration/dissolution of macromolecules derived from two stages, one rich in polymers, and low in solvent, called coacervated, and the other low in polymers and rich in solvent, called floating.

(52) Partial dehydration is performed under highly controlled conditions in order to avoid polymer precipitation, and in the process, several phenomena can be observed. When the solution is being stirred, there is a colloid-rich stage in scattered status, which can be observed as amorphous liquid drops.

(53) These drops are bound in a clear, homogeneous liquid film, rich in colloids, known as coacervated film, which is deposited and produced the material for the wall of the resulting capsules. Complex coacervation produces the simultaneous dissolution of 2 polymers, modifying the pH, as the ionic charges can neutralize each other, integrating a property into the rheology of the initial solution, either increasing or reducing viscosity.

Example 2. Liquid Ingredient Micro-Capsules Preparation Mode

(54) Process Description

(55) 1.active ingredient emulsion

(56) 2.matrix formation

(57) 3.coacervated cross-linking

(58) First stage: the emulsion is generated by adding the first materials as active ingredient with enough stirring to integrate them evenly. There is no increase in viscosity of the solution, only dispersion is obtained. The polymeric matrix-forming agent is added, and stirring continues for a certain period, in order to form appropriate globules to sequester the flavor, at this point, a light viscosity is reached, which does not interfere with the established flow, the vortex is appropriate, and there is enough shear force.

(59) Second stage: the surfactant and pH-modifying agents are added, as well as the rest of the matrix-forming agent, and the preservative. In case the micro-capsule must be pigmented, the previously dispersed colorant in water or oil is added, and stirring continues. Balance is reached, which can be observed through the increase or reduction in viscosity, and a change of color in the emulsion.

(60) Third stage: the cross-linking agent or the agent to harden the double film formed is added, making sure the stirring is not reduced. The emulsion is reduced, as well as the viscosity, which could even disappear. Stirring continues at a much slower speed, in order not to destroy the resulting micro-capsules with a weak shell, and not to go back to the emulsion-stage reaction. In this stage, the non-reactive supernatant material can be filtered or reintegrated into the dissolution bulk to obtain the solution with the appropriate particle size for the desired applications.

(61) 3. Ionic Microencapsulation

(62) Powdered Insecticide Micro-Capsules

(63) Components

(64) a.gelatin

(65) b.xanthan gum

(66) c.glutaraldehyde

(67) d.calcium chloride

(68) e.sodium hydroxide

(69) f.distilled water

(70) g.powdered active ingredient

(71) The main physical-chemical properties of insecticides to consider for the selection of the micro-capsules are as follows:

(72) a.Resistance to Alkalinity

(73) Alkalinity is natural and common in almost all materials used in the construction of houses and; thus, the supports on which the anti-insects paint is going to be applied. This is a relevant factor for the application of pesticides, as most active ingredients, especially organophosphates and carbamates, are decomposed in alkaline mediums. A pH between 5 and 6 is required for these ingredients to remain relatively stable (Table A).

(74) TABLE-US-00002 TABLE A Mean life of some active insecticide ingredients in aqueous mediums. Active ingredient Time to decompose (Mean life) Diflubenzuron Stable in pH between 5 and 7. Hydrolyzed at pH 9. Cypermethrin pH 9 (7 day). Stable at pH 4. Very stable in acid solutions. Deltamethrin pH 7 (8 hrs) more stable in medium acid solutions, than alkaline solutions D-allethrin Stable at pH 5 after 31 days. pH 7 (500 days) pH 9 (4.3 days) Chlorpyrifos At pH 10 (7 days). It is stable in neutral and lightly acid solutions. Diazinon pH 9 (136 days). pH 7.5 (185 days). pH 5 (31 days). Malathion Quickly hydrolyzed at pHs over 7. The optimal pH range is 5 and 6. Permethrin Stable at pH between 5 and 6. Methyl pirimiphos pH 8 (5 days). pH 5 (7 days). Pyriproxyfen Stable in a pH range between 4 and 9.

(75) The active micro-capsule release mechanisms are release by micro-capsule porosity, by thermal expansion, fracture by force, or pressure and friction.

(76) This alkaline hydrolysis causes a large reduction of the real efficacy of the formulation and, in general, it is directly proportional to the water alkalinity, or the alkalinity of the medium with which the formula makes contact.

(77) The micro-capsules of the invention herein maintain the insecticide active ingredients with an acid pH; thus, it is more resistant to alkalinity than other conventional paints.

(78) b. Adherence.

(79) Usually, exterior paint has adherence on surfaces such as concrete, cement and other mineral components frequently found on facades or walls. Nevertheless, other kind of materials can be found, on which the adherence of this paint is not satisfactory. The microcapsules of this invention do not interfere with high-adherence paint.

(80) c. Outdoor Durability.

(81) With this property, the capacity of the formulas to maintain their properties in the face of all kinds of external abiotic agents is measured, agents such as moisture, sunlight, temperature, pressure, and even biotic agents such as microorganisms, fungus, and other live beings.

(82) In the case of paint, all kinds of paint suffer from deterioration, in a higher or lower degree, when exposed to the weather. The most common effects are yellowing, cracking and chalk (superficial dust is released). In order to measure its resistant to the weather, they are exposed to accelerated aging, subjecting a sample to UV light, in more intense levels than usual, as well as variable moisture and temperature conditions. See Bureau Veritas study

(83) d. Resistance to Temperature.

(84) This property us particularly important in insecticides with active ingredients from the pyrethroid family, as these are quickly decomposed if exposed to high temperatures. Due to its formulation, this additive with microcapsules has a higher resistance to temperature than individual conventional insecticides.

(85) e. Wet Scrub Resistance.

(86) This property, additional to water resistance, indicates the washability degree of any coating. It is also a way to measure the paint resistance, in case of intense rain.

(87) In the preferred mode of the invention, as a receiving capsule (carrier) to encapsulate the microcapsules with at least one insecticide component or a mixture of two or more insecticide components and at least one reflective and/or photoluminescent, high-luminosity micro-encapsulated pigment, microsilica is used.

(88) In the preferred mode of the invention, the formula includes calcium carbonate as powdered excipient.

(89) Studies and investigations on the existing insecticides were carried out to determine the appropriate insecticides for the interaction with human beings, pets, farm animals and, specially, the ones that could repel and eliminate flying and crawling insects. After these studies, the optimal components for this development were determined and selected.

(90) On the other hand, options were analyzed to increase the product mean life, as well as its effectiveness from the double microencapsulation process; vital process in which the product increases its mean life and action for over 24 months.

(91) Below, some insecticides are described, which can be included in the formulation, among others.

(92) TABLE-US-00003 Insecticides Product Active Formu- Naming type ingredient Toxicity lation Coumaphos Insecticide Coumaphos Toxic Powder Trichlorfon Insecticide Metrifonate Mildly toxic Powder Boric acid Insecticide Hydrogen Group II Powder borate Mildly toxic N-methyl Insecticide Carbamate Group II Liquid carbamate Mildly toxic Carbofuran Insecticide Carbamate Group II Mildly toxic Alphacypermethrin Insecticide Cypermethrin powder

(93) In the preferred modality of the invention, the powdered additive formulation for its incorporation in coatings or substrates to repel, reduce and control insects consists of micro-encapsulated cypermethrin, micro-encapsulated deltamethrin, and boric acid, as insecticide actives, photoluminescent micro-encapsulated pigment (glow in the dark pigment), calcium carbonate as powdered excipient, and microsilica as receiving capsule (carrier).

(94) The insecticide mixes (active ingredients), their types and amounts, are handled by ranges according to the specific insects, as well as the gradual release effect.

(95) Formulation example:

(96) TABLE-US-00004 Active Amount in g Percentage (%) ingredient Minimum Maximum Minimum Maximum Micro- 0.01 1.5 0.07 10.0 encapsulated deltamethrin Boric acid 1 10 6.67 66.67 Micro- 1 8.5 6.67 56.67 encapsulate cypermethrin Calcium oxide 1 8 6.67 53.33

(97) The invention provides a production process for the powdered additive formulation for its incorporation in coatings or substrates to repel, reduce and control insects, which consists of: a) Microencapsulating the insecticide actives through microencapsulation by coacervation or ionic microencapsulation; b) Incorporating, in a food grade, stainless steel container, the micro-encapsulated insecticide actives, and the microsilica for around 25 to 30 minutes at a highest revolution of 400 rpm, otherwise, the microcapsule could be broken. Only these three elements must be added first, for the gaps in the microsilica to be filled with the insecticide actives, and to make those actives durable; c) Incorporating boric acid to the mix carefully, as the mix in the previous step is very volatile, and it can be toxic if inhaled. It is recommended to wear safety equipment at all times, and mix again at a speed of 400 rpm, for at least 20 more minutes, to obtain the optimal result; d) Adding calcium carbonate, only to give substance to the formula. Nevertheless, calcium carbonate of the highest quality possible must be used, otherwise, it will not be easily incorporated, which can result in a bad color in the final product. The mix must be done at a speed lower than 400 rpm for 20 more minutes.

(98) The production process of a powdered additive formulation for its incorporation to coatings or substrates to repel, reduce and control insects also consists of the following stage: e) Adding microcapsules with, at least, one reflective pigment and microcapsules with at least one photoluminescent pigment.

(99) In the modality in which the powdered additive formulation for its incorporation in coatings or substrates to repel, reduce and control insects is used as an ingredient in paint, 15 g of the formulation must be added per liter of water-based vinyl paint.

(100) The useful life of the paint may vary depending on the manufacturer. In this case, it is recommended to use paint with a 5-year useful life.

(101) For its production, special stainless steel, food grade equipment is required. This includes a mixer with sealed doors to avoid the mix volatility, with a speed regulator, as high speeds can break the microcapsule and/or generate excessive heat, which can break the microcapsule, and make the desired effect be reduced or disappear.

(102) This innovation is oriented towards the control and reduction of diseases transmitted by insects, mainly to vulnerable classes. This is a low-cost additive, and it is compatible with 90% of paint formulas, regardless of the price or brand.

(103) In addition, the invention provides the use of the powdered additive formulation defined by, at least, one active insecticide ingredient, or a combination of two or more active insecticide ingredients, with at least one reflective and/or photoluminescent, high-luminosity micro-encapsulated pigment, for its incorporation in coatings, paint, traditional insecticides, adhesives, binders, and other vehicles to repel, reduce and control insects.

(104) The formulation, according to the innovation herein, contains several competitive and differentiating advantages, from the technical and processing point of view (double microencapsulation, original formula and combination with luminescent elements), as well as from the practical point of view, as this formulation has a better performance for insect control, due to its mean life, over 24 months, as well as its luminescent effect to attract lucifuge insects with positive phototaxis, also repelling insects with negative phototaxis. Lastly, from the financial point of view, our product has a lower cost, in comparison to the products in the market, and it can be used on any kind of surface, which include, but are not limited to, the following: substrates such as textiles, paper, plastic, wood metal, stone, concrete, plaster, and any construction and interior decoration element. The social benefits are high, as our invention will have an important role in plague control, and the reduction of diseases transmitted by insects.

(105) An important part of double encapsulation is that, in the system, we incorporate the use of several micro-encapsulated insecticide elements that are released in different time lapses (two or more, depending on the number of insecticide families that are added to the formula). The release scheduled is controlled by the specific characteristics of the microcapsules used during the manufacturing process (size and shell). The benefits from this system allow the elimination of the immunity developed by insects to certain insecticides overtime, as different insecticide families are released overtime, it reduces the natural evolution of insects to generate immunity; hence, it allows an efficient plague control.

(106) The invention has been described enough, for a person with average knowledge on the matter to be able to reproduce and obtain the results mentioned in the innovation herein. Nevertheless, any person with skills on the field can make modifications that are not written in this application, but in order to apply these modifications on a certain structure, or in the manufacturing process thereof, the matters stated in the following claims are required, such structures must be included in the invention scope.