EP4247930A1

EP4247930A1 - Method of making detergent compositions comprising perfume

Info

Publication number: EP4247930A1
Application number: EP20961922.0A
Authority: EP
Inventors: Dan Xu; Xi Chen; Hanjiang ZHU
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 2020-11-19
Filing date: 2020-11-19
Publication date: 2023-09-27
Also published as: CN116507708A; WO2022104631A1

Abstract

A process of making a granular detergent composition comprising the steps of: a) providing a plurality of detergent particles; b) forming a premix comprising a liquid protective agent and a perfume; and c) adding the premix from step b) to at least a portion of said plurality of detergent particles.

Description

METHOD OF MAKING DETERGENT COMPOSITIONS COMPRISING PERFUME

FIELD OF THE INVENTION

The present invention is directed to methods of making granular detergent compositions containing perfume.

BACKGROUND OF THE INVENTION

Granular laundry detergent compositions are well known. Granular laundry detergent compositions comprise one or more surfactants which can provide a good fabric-cleaning performance. Genearlly, granular laundry detergent compositions can be prepared by using different processes including spray-drying and agglomerate. Spray-drying is the standard method for manufacturing laundry detergent base powder. Typically, detergent ingredients are mixed together to form an aqueous detergent slurry in a mixer, such as a crutcher mixer. This slurry is then transferred along a pipe through a first low pressure pump and then through a second high pressure pump to a spray nozzle, and the slurry is sprayed into a spray-drying tower, and spray-dried to form a spray-dried powder. Typically, a suitable agglomeration process comprises the step of contacting a detersive ingredient, such as a detersive surfactant, e.g. linear alkyl benzene sulphonate (LAS) and/or alkyl alkoxylated sulphate, with an inorganic material, such as sodium carbonate and/or silica, in a mixer.
Preferably, in addition to surfactants, perfume is often added in laundry detergents to delight consumers. For granular detergent products, perfume is generally added by spraying onto base detergent particles, such as spray-dried base detergent particles and/or agglomerated base detergent particles. Typically, this spray-on step is carried out in a tumbling drum mixer.
However, the inventors of the present invention notice that the spray-on perfume is not sufficiently stable due to various causes, e.g. evaporation and/or degradation during the making and storage. Currently, one of the solutions is to increase perfume level so as to secure superiority of the final products to consumers, which apparently results in a higher cost.
Thus, there is a need in the art for a new approach to improve the stability of the spray-on perfume in the granular detergent products.
The inventors of the present invention have surprisingly found that if perfume is pre-mixed with a liquid protective agent before spraying onto the detergent particles, the stability is significantly improved. As such, the total amount of perfume needed for the making of granular detergent products can be reduced, resulting in cost saving.
SUMMARY OF THE INVENTION
The present invention addresses the aforementioned needs by providing the following method of making a granular detergent composition.
In one aspect, the present invention relates to a process of making a granular detergent composition comprising the steps of: a) providing a plurality of detergent particles; b) forming a premix comprising a liquid protective agent and a perfume; and c) adding the premix from step b) to at least a portion of said plurality of detergent particles.
In another aspect, the present invention relates to a system for making a granular detergent composition, wherein said system comprises i) a rotating drum comprising a nozzle located inside said rotating drum, ii) a static mixer which is in fluid communication with said nozzle, and iii) a first reservoir for containing a perfume and a second reservoir for containing a liquid protective agent, in which said first and second reservoirs are both in fluid communication with said static mixer. Preferably, the liquid protective agent is selected from a non-ionic surfactant, a non-ionic polymer, α‐aryl esters and any combinations thereof. More preferably, the liquid protective agent is selected from alkyl alkoxylated alcohols, polyethylene glycols, benzyl benzoate, phenyl salicylate, and any combinations thereof.
It is an advantage of the process to improve the stability of perfume in the granular detergent products.
It is another advantage of the process to reduce the amount of perfume needed in the granular detergent products.
It is another advantage of the process to save cost for making granular detergent products.
These and other features, aspects and advantages of specific embodiments will become evident to those skilled in the art from a reading of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments set forth in the drawings are illustrative in nature and not intended to limit the invention defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, and in which:
Figure 1 illustrates the step of spraying perfume onto detergent particles in the current process (Comparative Process) and the test processes (Test Process 1 and Test Process 2) .
Figure 2 illustrates the improved stability of perfume in the test processes compared to the current process.

DETAILED DESCRIPTION OF THE INVENTION

All percentages, parts and ratios are based upon the total weight of the composition of the present invention and all measurements made are at 25℃, unless otherwise specified. All such weights as they pertain to listed ingredients are based on the active level and therefore do not include carriers or by-products that may be included in commercially available materials, unless otherwise specified.
Process of making
The present invention is related to a process of making a granular detergent composition comprising the steps of:
a) providing a plurality of detergent particles;
b) forming a premix comprising a liquid protective agent and a perfume; and
c) adding the premix from step b) to at least a portion of said plurality of detergent particles.
Particularly, the detergent particles can be prepared by any suitable process. For example: spray-drying, agglomeration, extrusion and any combination thereof.
Typically, the spray drying process includes spraying an aqueous slurry comprising detergent ingredients into a spray-drying tower through which hot air flows. As it falls through the tower, the aqueous slurry forms droplets, the hot air causes water to evaporate from the droplets, and a plurality of spray-dried granules is formed. Preferably, the spray-drying tower is a counter-current spray-drying tower, although a co-current spray-drying tower may also be suitable. The resulting granules may form the finished granular detergent composition. Alternatively, the resulting granules may be further processed (such as via agglomeration) and/or further components (such as detergent adjuncts) may be added thereto.
Typically, the spray-dried powder is subjected to cooling, for example an air lift. Typically, the spray-drying powder is subjected to particle size classification, for example a sieve, to obtain the desired particle size distribution. Preferably, the spray-dried powder has a particle size distribution such that weight average particle size is in the range of from 300 micrometers to 500 micrometers, and less than 10wt%of the spray-dried particles have a particle size greater than 2360 micrometers.
It may be preferred to heat the aqueous slurry mixture to elevated temperatures prior to atomization into the spray-drying tower, such as described in WO2009/158162.
It may be preferred for anionic surfactant, such as linear alkyl benzene sulphonate, to be introduced into the spray-drying process after the step of forming the aqueous slurry mixture: for example, introducing an acid precursor to the aqueous slurry mixture after the pump, such as described in WO 09/158449.
It may be preferred for a gas, such as air, to be introduced into the spray-drying process after the step of forming the aqueous slurry, such as described in WO2013/181205.
It may be preferred for any inorganic ingredients, such as sodium sulphate and sodium carbonate, if present in the aqueous slurry mixture, to be micronized to a small particle size such as described in WO2012/134969.
Typically, a suitable agglomeration process comprises the step of contacting a detersive ingredient, such as a detersive surfactant, e.g. linear alkyl benzene sulphonate (LAS) and/or alkyl alkoxylated sulphate, with an inorganic material, such as sodium carbonate and/or silica, in a mixer. The agglomeration process may also be an in-situ neutralization agglomeration process wherein an acid precursor of a detersive surfactant, such as LAS, is contacted with an alkaline material, such as carbonate and/or sodium hydroxide, in a mixer, and wherein the acid precursor of a detersive surfactant is neutralized by the alkaline material to form a detersive surfactant during the agglomeration process.
Other suitable detergent ingredients that may be agglomerated include polymers, chelants, bleach activators, silicones and any combination thereof.
The agglomeration process may be a high, medium or low shear agglomeration process, wherein a high shear, medium shear or low shear mixer is used accordingly. The agglomeration process may be a multi-step agglomeration process wherein two or more mixers are used, such as a high shear mixer in combination with a medium or low shear mixer. The agglomeration process can be a continuous process or a batch process.
It may be preferred for the agglomerates to be subjected to a drying step, for example to a fluid bed drying step. It may also be preferred for the agglomerates to be subjected to a cooling step, for example a fluid bed cooling step.
Typically, the agglomerates are subjected to particle size classification, for example a fluid bed elutriation and/or a sieve, to obtain the desired particle size distribution. Preferably, the agglomerates have a particle size distribution such that weight average particle size is in the range of from 300 micrometers to 800 micrometers, and less than 10wt%of the agglomerates have a particle size less than 150 micrometers and less than 10wt%of the agglomerates have a particle size greater than 1200 micrometers.
It may be preferred for fines and over-sized agglomerates to be recycled back into the agglomeration process. Typically, over-sized particles are subjected to a size reduction step, such as grinding, and recycled back into an appropriate place in the agglomeration process, such as the mixer. Typically, fines are recycled back into an appropriate place in the agglomeration process, such as the mixer.
It may be preferred for ingredients such as polymer and/or non-ionic detersive surfactant and/or perfume to be sprayed onto base detergent particles, such as spray-dried base detergent particles and/or agglomerated base detergent particles. Typically, this spray-on step is carried out in a tumbling drum mixer.
Particularly, the addition of the premix in step c) is achieved by spraying the premix on said plurality of detergent particles, preferably inside a rotating drum.
In some embodiments, in step b) , the premix is formed by mixing the liquid protective agent and the perfume in a mixer, preferably a static mixer.
In some embodiments, in step b) , said liquid protective agent and said perfume are mixed at an average shear rate of from 10 to 10000 s ^-1 , preferably from 20 to 5000 s ^-1, more preferably from 40 to 7000 s ^-1.
In some embodiments, the liquid protective agent is an alkyl alkoxylated alcohol having an average degree of alkoxylation of from 1 to 50, preferably a linear or branched, substituted or unsubstituted C _8-18 alkyl ethoxylated alcohol having an average degree of ethoxylation of from 1 to 12, more preferably from 5 to 10.
In some embodiments, the weight ratio of the liquid protective agent to the perfume in the premix is from 0.05 to 50, preferably from 0.1 to 20, more preferably from 0.2 to 10.
In some embodiments, the detergent particles are spray-dried, extruded or agglomerate particles.
In some embodiments, the detergent particles may comprise a detersive surfactant preferably selected from the group of: alkyl benzene sulfonate; alkoxylated alkyl sulfate; alkyl sulfate; alkoxylated alcohol; and mixtures thereof.
In some embodiments, the detergent particles may comprise at least one additional detergent ingredient preferably selected from the group of: polymeric carboxylate; chelant; starch; sodium sulphate; citric acid; cellulosic polymer; suds suppressor; fluorescent whitening agent; hueing agent; flocculating agent; polyester soil release agent; or a mixture thereof.
In another aspect, the present invention relates to a system for making a granular detergent composition, wherein said system comprises i) a rotating drum comprising a nozzle located inside said rotating drum, ii) a static mixer which is in fluid communication with said nozzle, and iii) a first reservoir for containing a perfume and a second reservoir for containing a liquid protective agent, in which said first and second reservoirs are both in fluid communication with said static mixer.
Detersive Surfactant
Any suitable detersive surfactant is of use in the granular detergent composition.
Suitable detersive surfactants include, but are not limited to: anionic surfactants, non-ionic surfactants, cationic surfactants, zwitterionic surfactants, amphoteric surfactants and any mixtures thereof. Preferred surfactants include anionic surfactants, cationic surfactants, non-ionic surfactants and any mixtures thereof.
Suitable anionic surfactants can include alkyl benzene sulphonate. Preferably the anionic detersive surfactant comprises at least 50 wt%, at least 55 wt%, at least 60 wt%, at least 65 wt%, at least 70 wt%, at least 75 wt%, at least 80 wt%, at least 85 wt%, at least 90 wt%, or even at least 95 wt%, by weight of the anionic detersive surfactant, of alkyl benzene sulphonate. The alkyl benzene sulphonate is preferably a linear or branched, substituted or unsubstituted, C _8-18 alkyl benzene sulphonate. This is the optimal level of the C _8-18 alkyl benzene sulphonate to provide a good cleaning performance. The C _8-18 alkyl benzene sulphonate can be a modified alkylbenzene sulphonate (MLAS) as described in more detail in WO 99/05243, WO 99/05242, WO 99/05244, WO 99/05082, WO 99/05084, WO 99/05241, WO 99/07656, WO 00/23549, and WO 00/23548. Highly preferred C _8-18 alkyl benzene sulphonates are linear C _10-13 alkylbenzene sulphonates. Especially preferred are linear C _10-13 alkylbenzene sulphonates that are obtainable by sulphonating commercially available linear alkyl benzenes (LAB) ; suitable LAB include low 2-phenyl LAB, such as those supplied by Sasol under the trade name or those supplied by Petresa under the trade name Other suitable LAB include high 2-phenyl LAB, such as those supplied by Sasol under the trade name
The anionic detersive surfactant may preferably comprise other anionic detersive surfactants. A suitable anionic detersive surfactant is a non-alkoxylated anionic detersive surfactant. The non-alkoxylated anionic detersive surfactant can be an alkyl sulphate, an alkyl phosphate, an alkyl phosphonate, an alkyl carboxylate or any mixture thereof. The non-alkoxylated anionic surfactant can be selected from the group consisting of; C ₁₀-C ₂₀ primary, branched-chain, linear-chain and random-chain alkyl sulphates (AS) , typically having the following formula (I) :
CH ₃ (CH ₂) _xCH ₂-OSO ₃ ^-M ⁺
wherein, M is hydrogen or a cation which provides charge neutrality, preferred cations are sodium and ammonium cations, wherein x is an integer of at least 7, preferably at least 9; C ₁₀-C ₁₈ secondary (2, 3) alkyl sulphates, typically having the following formulae:
wherein, M is hydrogen or a cation which provides charge neutrality, preferred cations include sodium and ammonium cations, wherein x is an integer of at least 7, preferably at least 9, y is an integer of at least 8, preferably at least 9; C ₁₀-C ₁₈ alkyl carboxylates; mid-chain branched alkyl sulphates as described in more detail in US 6,020,303 and US 6,060,443; methyl ester sulphonate (MES) ; alpha-olefin sulphonate (AOS) ; and mixtures thereof.
Another preferred anionic detersive surfactant is an alkoxylated anionic detersive surfactant. The presence of an alkoxylated anionic detersive surfactant in the spray-dried powder provides good greasy soil cleaning performance, gives a good sudsing profile, and improves the hardness tolerance of the anionic detersive surfactant system. It may be preferred for the anionic detersive surfactant to comprise from 1%to 50%, or from 5%, or from 10%, or from 15%, or from 20%, and to 45%, or to 40%, or to 35%, or to 30%, by weight of the anionic detersive surfactant system, of an alkoxylated anionic detersive surfactant.
Preferably, the alkoxylated anionic detersive surfactant is a linear or branched, substituted or unsubstituted C _12-18 alkyl alkoxylated sulphate having an average degree of alkoxylation of from 0.5 to 30, preferably from 0.5 to 10, more preferably from 0.5 to 3. Preferably, the alkoxylated anionic detersive surfactant is a linear or branched, substituted or unsubstituted C _12-18 alkyl ethoxylated sulphate having an average degree of ethoxylation of from 0.5 to 10, more preferably from 0.5 to 3. Most preferably, the alkoxylated anionic detersive surfactant is a linear unsubstituted C _12-18 alkyl ethoxylated sulphate having an average degree of ethoxylation of from 0.5 to 7, more preferably from 0.5 to 3.
The alkoxylated anionic detersive surfactant, when present with an alkyl benzene sulphonate may also increase the activity of the alkyl benzene sulphonate by making the alkyl benzene sulphonate less likely to precipitate out of solution in the presence of free calcium cations. Preferably, the weight ratio of the alkyl benzene sulphonate to the alkoxylated anionic detersive surfactant is in the range of from 1: 1 to less than 5: 1, or to less than 3: 1, or to less than 1.7: 1, or even less than 1.5: 1. This ratio gives optimal whiteness maintenance performance combined with a good hardness tolerance profile and a good sudsing profile. However, it may be preferred that the weight ratio of the alkyl benzene sulphonate to the alkoxylated anionic detersive surfactant is greater than 5: 1, or greater than 6: 1, or greater than 7: 1, or even greater than 10: 1. This ratio gives optimal greasy soil cleaning performance combined with a good hardness tolerance profile, and a good sudsing profile.
Additional Detergent Ingredients
The additional detergent ingredient may include a builder. Any suitable builder may be of use in the granular detergent composition. Suitable builders include, but are not limited to those selected from the group of: zeolite builder; phosphate builder; and mixtures thereof. Non-limiting examples of useful zeolite builders include: zeolite A; zeolite X; zeolite P; zeolite MAP; and combinations thereof. Sodium tripolyphosphate is a non-limiting example of a useful phosphate builder. The zeolite builder (s) may be present at from about 1 to about 20 %by weight of the detergent composition. It may also be especially preferred for the granular detergent composition to comprise low levels, or even be essentially free, of builder. By essentially free of it is typically meant herein to mean: “comprises no deliberately added” . In a preferred embodiment, the granular detergent composition is essentially free of zeolite, preferably has no zeolite. In a preferred embodiment, the granular detergent composition is essentially free of phosphate, preferably has no phosphate.
The additional detergent ingredient may include a polymer. Any suitable polymer may be of use in the granular detergent composition. Suitable polymers include, but are not limited to: polymeric carboxylate; polyester soil release agent; cellulosic polymer; and mixtures thereof. One preferred polymeric material is a polymeric carboxylate, such as a co-polymer of maleic acid and acrylic acid. However, other polymers may also be suitable, such as polyamines (including the ethoxylated variants thereof) , polyethylene glycol and polyesters. Polymeric soil suspending aids and polymeric soil release agents are also particularly suitable.
Another suitable polymer is cellulosic polymer, such as cellulosic polymer selected from the group of: alkyl alkoxy cellulose, preferably methyl hydroxyethyl cellulose (MHEC) ; alkyl cellulose, preferably methyl cellulose (MC) ; carboxy alkyl cellulose, preferably carboxymethylcellulose (CMC) ; and mixtures thereof.
Polymers may be present at from about 0.5 to about 20%or from about 1 to about 10%by weight of the detergent composition.
Other suitable detergent ingredients may be selected from the group of: chelants such as ethylene diamine disuccinic acid (EDDS) ; hydroxyethylene diphosphonic acid (HEDP) ; starch; sodium sulphate; carboxylic acids such as citric acid or salts thereof such as citrate; suds suppressor; fluorescent whitening agent; hueing agent; flocculating agent such as polyethylene oxide; and mixtures thereof. If the present detergent comprises masking agents and/or whiteners (e.g. Titanium dioxide) , they may be present at less than about 1 wt%or less.
Liquid protective agent
Surprisingly, the inventors of the present invention found that it can significantly improve the stability of perfume to premix the perfume with a liquid protective agent before spraying onto the detergent particles.. Without wishing to be bound by theory, it is believed that the non-ionic surfanct may play a protective role for perfume to prevent evaporation during the making (i.e. inside the rotating drum) and/or the storage. Preferably, the liquid protective agent is selected from a non-ionic surfactant, a non-ionic polymer, α‐aryl esters and any combinations thereof. More preferably, the liquid protective agent is selected from alkyl alkoxylated alcohols, polyethylene glycols, benzyl benzoate, phenyl salicylate, and any combinations thereof.
The non-ionic surfactant for use in the premix could be an alkyl polyglucoside and/or an alkyl alkoxylated alcohol. Preferably the non-ionic surfactant is a linear or branched, substituted or unsubstituted C _8-18 alkyl ethoxylated alcohol having an average degree of ethoxylation of from 1 to 10.
Suitable non-ionic surfactants include alkyl polyglucoside and/or an alkyl alkoxylated alcohol. Preferred non-ionic alkyl alkoxylated alcohols include C _8-18 alkyl alkoxylated alcohol, preferably a C _8-18 alkyl ethoxylated alcohol, preferably the alkyl alkoxylated alcohol has an average degree of alkoxylation of from 1 to 50, preferably from 1 to 30, or from 1 to 20, or from 1 to 10, preferably the alkyl alkoxylated alcohol is a C _8-18 alkyl ethoxylated alcohol having an average degree of ethoxylation of from 1 to 20, preferably from 5 to 10. The alkyl alkoxylated alcohol can be linear or branched, and substituted or un-substituted. Suitable non-ionic surfactants can be selected from the group consisting of: C ₈-C ₁₈ alkyl ethoxylates, such as, non-ionic surfactants from Shell; C ₆-C ₁₂ alkyl phenol alkoxylates wherein preferably the alkoxylate units are ethyleneoxy units, propyleneoxy units or a mixture thereof; C ₁₂-C ₁₈ alcohol and C ₆-C ₁₂ alkyl phenol condensates with ethylene oxide/propylene oxide block polymers such as from BASF; C ₁₄-C ₂₂ mid-chain branched alcohols; C ₁₄-C ₂₂ mid-chain branched alkyl alkoxylates, preferably having an average degree of alkoxylation of from 1 to 30; alkylpolysaccharides, preferably alkylpolyglycosides; polyhydroxy fatty acid amides; ether capped poly (oxyalkylated) alcohol surfactants; and mixtures thereof.
Suitable non-ionic surfactants for use in the premix can be selected from the group of: C ₈-C ₁₈ alkyl ethoxylates, such as, non-ionic surfactants from Shell; C ₆-C ₁₂ alkyl phenol alkoxylates wherein the alkoxylate units are ethyleneoxy units, propyleneoxy units or a mixture thereof; C ₁₂-C ₁₈ alcohol and C ₆-C ₁₂ alkyl phenol condensates with ethylene oxide/propylene oxide block polymers such as from BASF; C ₁₄-C ₂₂ mid-chain branched alcohols, BA, as described in more detail in US 6,150,322; C ₁₄-C ₂₂ mid-chain branched alkyl alkoxylates, BAEx, wherein x = from 1 to 30, as described in more detail in US 6,153,577, US 6,020,303 and US 6,093,856; alkylpolysaccharides as described in more detail in US 4,565,647, specifically alkylpolyglycosides as described in more detail in US 4,483,780 and US 4,483,779; polyhydroxy fatty acid amides as described in more detail in US 5,332,528, WO 92/06162, WO 93/19146, WO 93/19038, and WO 94/09099; ether capped poly (oxyalkylated) alcohol surfactants as described in more detail in US 6,482,994 and WO 01/42408; and mixtures thereof.
Suitable non-ionic polymers for use in the premix can be selected from the group consisting of polyethylene glycols, polypropylene glycols, and other polymers.
Suitable α‐aryl esters for use in the premix can be selected from the group consisting of benzoates, salicylates, and any combinations thereof, for example benzyl benzoate, phenyl salicylate.
The Granular Detergent Composition
The granular detergent composition is suitable for any laundry detergent application, for example: laundry, including automatic washing machine laundering and hand laundering, and even bleach and laundry additives.
The granular detergent composition can be a fully formulated detergent product, such as a fully formulated laundry detergent product, or it can be combined with other particles to form a fully formulated detergent product, such as a fully formulated laundry detergent product. The granular detergent composition may be combined with other particles such as: enzyme particles; perfume particles including agglomerates or extrudates of perfume microcapsules, and perfume encapsulates such as starch encapsulated perfume accord particles; surfactant particles, such as non-ionic detersive surfactant particles including agglomerates or extrudates, anionic detersive surfactant particles including agglomerates and extrudates, and cationic detersive surfactant particles including agglomerates and extrudates; polymer particles including soil release polymer particles, cellulosic polymer particles; buffer particles including carbonate salt and/or silicate salt particles, preferably a particle comprising carbonate salt and silicate salt such as a sodium carbonate and sodium silicate co-particle, and particles and sodium bicarbonate; other spray-dried particles; fluorescent whitening particles; aesthetic particles such as coloured noodles or needles or lamellae particles; bleaching particles such as percarbonate particles, especially coated percarbonate particles, including carbonate and/or sulphate coated percarbonate, silicate coated percarbonate, borosilicate coated percarbonate, sodium perborate coated percarbonate; bleach catalyst particles, such as transition metal catalyst bleach particles, and imine bleach boosting particles; performed peracid particles; hueing dye particles; and any mixture thereof.
The granular detergent composition according to the present invention may have a bulk density of from about 250 to about 550 grams per liter, or from about 400 to about 800 grams per liter. The granular detergent composition may have a mean particle granule size of from about 300 to about 550 microns, or from about 350 to about 450 microns.
EXAMPLES
Example 1. Improved stability of perfume by premixing the perfume with non-ionic surfactant compared to separately adding perfume and non-ionic surfactant
Comparative Process and Test Proces 1 and 2 for making granular detergent products are summarized in Fig. 1 in which non-ionic surfactants (NI) and perfume were separately sprayed onto the blended particles of blown powder (BP) of detersive surfactants and other solid particles for other ingredients in Comparative Process and then final products (FP) were prepared after the perfume was added. NI was pre-heated at 40-45 ℃ before the experiments in all 3 processes. In Test Process 1 and 2, NI and perfume were firstly mixed with an IKA mixer (type: ULTRA TURRAX T25 basic) at 6500 rpm for 20 seconds to provide a premix before spraying onto the detergent particles, the shear head was located under the interface to avoid aeration; in which the premix was sprayed onto the blended particles of BP and other solids in Test Process 1 and the premix was sprayed onto BP and then blended with other solid particles in Test Process 2.
The processes as mentioned above were conducted in an Aichi rocking mixer (type: RM-10-3) . The composition of the final products is summarized in the following table.
Table 1. Composition of the finished product

Raw material	wt%
Tide BP ¹	72.0

Sodium sulfate	22.3
Zeolite	2.7
Alkyl sulfate	0.6
Non-ionic surfactant ²	1.0
Perfume	0.3
Fluorescent whitening agent	0.1
Miscellaneous	Balance

1: Tide BP from P&G containing C ₈-C ₂₄ alkyl benzene sulphonate; silicate; acrylic acid/maleic acid copolymer ; brightener, Na ₂CO ₃, and Na ₂SO ₄
2: C ₁₂-C ₁₅ alkyl ethoxylate from Shell
The stability of perfume in the final products was assessed via the standard odor stability test, in which every1 kg FP was loaded into P&G Ariel NL230 carton and then the cartons were placed in a 32 ℃/80%RH CTCH oven for three weeks. One carton was taken out every week for perfume content determination. The remaining perfume content was measured by a GC-MS (Agilent, GC type: 7890B MS type: 5977B) and odor was graded by the sensory panel. Normalized percentage of perfume was calculated by the equation:
Normalized percentage of perfume = perfume content in FP prepared by Test Process ÷perfume content in FP prepared by Comparative Process
The results shown in Fig. 2 indicate that mixing perfume and NI before the spraying brings about improved stability compared to separately spraying perfume and NI.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm. ”
Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

A process of making a granular detergent composition comprising the steps of:

a) providing a plurality of detergent particles;

b) forming a premix comprising a liquid protective agent and a perfume; and

c) adding said premix from step b) to at least a portion of said plurality of detergent particles so as to provide said granular detergent composition.
The process according to claim 1, wherein the addition of said premix in step c) is achieved by spraying said premix on said plurality of detergent particles, preferably inside a rotating drum.
The process according to claim 1 or 2, wherein in step b) , said premix is formed by mixing said liquid protective agent and said perfume in a mixer, preferably a static mixer.
The process according to claim 3, wherein in step b) , said liquid protective agent and said perfume are mixed at an average shear rate of from 10 to 10000 s ^-1 , preferably from 20 to 5000 s ^-1, more preferably from 40 to 7000 s ^-1.
The process according to any one of claims 1 to 4, wherein the liquid protective agent is selected from the group consisting of a non-ionic surfactant, a non-ionic polymer, α‐aryl esters and any combinations thereof,

preferably, the non-ionic surfactant liquid protective agent is selected from the group consisting of alkyl alkoxylated alcohols, polyethylene glycols, benzyl benzoate, phenyl salicylate, and any combinations thereof, and

more preferably, the non-ionic surfactant liquid protective agent is selected from the group consisting of alkyl alkoxylated alcohols.
The process according to claim 5, wherein said liquid protective agent is an alkyl alkoxylated alcohol having an average degree of alkoxylation of from 1 to 50, preferably a linear or branched, substituted or unsubstituted C _8-18 alkyl ethoxylated alcohol having an average degree of ethoxylation of from 1 to 10, more preferably from 5 to 10.
The process according to any one of claims 1 to 6, wherein the weight ratio of said liquid protective agent to said perfume in said premix is from 0.1 to 50, preferably from 0.5 to 20, more preferably from 0.2 to 10.
The process according to any one of claims 1 to 7, wherein said plurality of detergent particles are spray-dried, extruded or agglomerate particles.
The process according to any one of claims 1 to 8, wherein said plurality of detergent particles comprise a detersive surfactant preferably selected from the group consisting of alkyl benzene sulfonate, alkoxylated alkyl sulfate, alkyl sulfate, alkoxylated alcohol, and mixtures thereof.
The process according to any one of claims 1 to 9, wherein said plurality of detergent particles further comprise at least one additional detergent ingredient preferably selected from the group consisting of polymeric carboxylate, chelant, starch, sodium sulphate, citric acid, cellulosic polymer, suds suppressor, fluorescent whitening agent, hueing agent, flocculating agent, polyester soil release agent, and mixtures thereof.
A process of making a granular detergent composition comprising the steps of:

a) providing a first plurality of detergent particles and a second plurality of detergent particles in which said first plurality of detergent particles comprise a detersive surfactant selected from the group consisting of alkyl benzene sulfonate, alkoxylated alkyl sulfate, alkyl sulfate, alkoxylated alcohol, and mixtures thereof and said second plurality of detergent particles further comprise at least one additional detergent ingredient selected from the group consisting of polymeric carboxylate, chelant, starch, sodium sulphate, citric acid, cellulosic polymer, suds suppressor, fluorescent whitening agent, hueing agent, flocculating agent, polyester soil release agent, and mixtures thereof;

b) forming a premix comprising a liquid protective agent and a perfume;

c) adding said premix from step b) to at least a portion of said first plurality of detergent particles to provide a plurality of perfume-containing detergent particles; and

d) mixing said second plurality of detergent particles and said plurality of perfume-containing detergent particles so as to provide said granular detergent composition.
A system for making a granular detergent composition, wherein said system comprises:

i. a rotating drum comprising a nozzle located inside said rotating drum,

ii. a static mixer which is in fluid communication with said nozzle, and

iii. a first reservoir for containing a perfume and a second reservoir for containing a liquid protective agent, in which said first and second reservoirs are both in fluid communication with said static mixer.