Patent Publication Number: US-4253981-A

Title: Viscous lubricant composition comprising mixed esters and a silicone oil

Description:
This invention is concerned with the provision of a viscous composition adapted to be used as a lubricant, surface protectant, moisture repelling agent, carrier for additives, or as a means for supplying agents for topical application. More particularly among the objects of this invention is the provision of a viscous composition whose manufacture is relatively simple, economical, and requires minimal space and machinery. Additionally, it is an object of this invention to provide such viscous preparation having substantially no tendency toward separation of ingredients and having the ability to retain its viscosity over a range of temperatures outside of those ordinarily encountered in vehicles used for topical application. 
     In accordance with the foregoing objects and desiderata I have discovered that a composition comprising a mixture of diisopropyl adipate, octanoic acid esters such as cetyl and stearyl, glyceryl tribehenate, a silicone oil and a surfactant possesses the aforesaid properties and characteristics and in addition exhibits pseudoplastic behavior. 
     In the practice of my invention I prefer that diisopropyl adipate and the mixture of cetyl and stearyl octanoates, sometimes referred to as purcellin oil, constitute the bulk of the composition, being present in the amount from 79-92% of its total weight. The silicone oil, having a viscosity of from 5-1000 cps, provides from 2.5-10% of the composition. The triglyceride, glyceryl tribehenate, may be present at a level from 5-15% but preferably 10% and a nonionic surfactant having a hydrophile-lipophile balance from 1.8-4 but preferably 4 at a level of 0.2-1.5% but preferably 0.5% makes up the remainder. 
    
    
     Representative formulae are the following: 
     EXAMPLE 1 
     
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                        %                                                 
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Diisopropyl Adipate       20.0                                            
Purcellin Oil             59.5                                            
Glyceryl Tribehenate      10.0                                            
Silicone Oil 100 cps      10.0                                            
Surfactant                 0.5                                            
(88% Sorbitan Monooleate +                                                
12% Sorbitan Trioleate).                                                  
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     EXAMPLE 2 
     
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                        %                                                 
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Diisopropyl Adipate       20.0                                            
Purcellin Oil             64.5                                            
Glyceryl Tribehenate      10.0                                            
Silicone Oil 100 cps      5.0                                             
Surfactant                0.5                                             
(88% Sorbitan Monooleate +                                                
12% Sorbitan Trioleate).                                                  
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     Viscosity measurements using a Brookfield Viscometer Model LV, spindle T-A on the composition of Example 1 at different temperatures were: 
     
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Temp. ° C.                                                         
                 Viscosity cps                                            
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30°       28,000                                                   
24°       30,000                                                   
10°       32,000                                                   
 5°       30,000                                                   
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     The preparation of the compositions of my invention is described as follows; temperatures are in Celsius. 
     The components are melted at a temperature of 65-70° and stirred until homogenous. The mixture is then rapidly cooled with vigorous stirring until the temperature is below 12°. Preferably between 8° and 10°. The preparation is passed through a conventional spring jet homogeniser. Any conventional homogenisation method may be used providing the temperature is kept between 8° and 10°.