Abstract:
A combination of low frequency high amplitude sonic frequency vibrations and high frequency low intensity ultrasonic pressure waves are applied to cosmetic compounds and to the skin to promote improved penetration of the cosmetic compounds into the epidermis. The cosmetic applicator device includes means for generating both sonic frequency vibrations and ultrasonic pressure waves adopted to deliver cosmetic compounds into the epidermis safely without significant temperature rise in the skin. Various removable applicator and skin cleaning attachments are also disclosed, including some with ultrasound waveguide.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a Continuation-in-Part application of Ser. No. 14/634,556 filed Feb. 27, 2015, the contents of which are hereby incorporated by reference in their entireties as if fully set forth herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to sonic and/or ultrasonic devices for cosmetic applications. 
       BACKGROUND OF THE INVENTION 
       [0003]    The stratum corneum, the outermost layer of the epidermis consists of dead cells (corneocytes). The purpose of this layer of dead skin is to form a barrier to protect underlying living tissue from infection, dehydration, and chemical attacks. 
         [0004]    Unfortunately, the same low permeability barrier characteristic of the stratum corneum, which protects the body from infections, also resists the penetration of beneficial cosmetic and chemical compounds, such as moisturizers, alpha-hydroxyl acids, collagen, vitamins and vasodilators. In addition, oily and congested skin conditions are also reducing the penetration of beneficial skin treatment compounds. 
         [0005]    The invention is concerned with methods and apparatus facilitating the use of sonic and ultrasonic energy coupled to the skin to temporarily increase the permeability of the skin and enhance the absorption of beneficial cosmetic and chemical compounds into the skin, and particularly to direct and focus the ultrasound energy into small restricted areas such as the nose and face interface by the utilization of an ultrasound waveguide. 
       DESCRIPTION OF PRIOR ART 
       [0006]    Numerous attempts have been made in the past to enhance the penetrations of cosmetic compounds into the skin by chemical, electrical and ultrasonic means. 
         [0007]    The application of chemicals to modify the skin structure to allow the penetration of cosmetics was found to be dangerous because while it provided access for cosmetics to penetrate, it left the body unprotected against harmful environments, interacting with corneocytes causing irritation, erythema (red skin) and contact dermatitis. 
         [0008]    The application of electrical fields to create transient transport pathways by a method called electroporation, and the method to electrically charge molecules to increase their penetration into the skin called iontophoresis (U.S. Pat. No. 6,169,920), have both been proven costly and ineffective. Electrical abrasion devices for increasing the skin&#39;s permeability (U.S. Pat. No. 8,386,027) remove some layers of the stratum corneum causing intense irritation and discomfort. 
         [0009]    The effort of prior art of ultrasonically induced drug delivery (sonophoresis) described in U.S. Pat. No. 6,322,532 is focused in driving drug molecules through the skin by high frequency and high intensity ultrasonic pressure waves. This procedure suffers from the disadvantage of tissue heating and the associated modification and sometimes destruction of healthy cells. 
         [0010]    To achieve a non tissue heating modality, ultrasound devices described by McDaniel (US 2001/0041856), Reed (US 2009/0318853 A1), and Bock (U.S. Pat. No. 5,618,275) are typically operate at 35 mW/cm 2  intensity and utilizing ultrasound transducers of 12 mm diameter and larger. While these devices are highly suitable for use on large flat surface areas of the face, these devices will not fit into and cannot apply the compounds into restricted areas such as the intersection of the face and the nose and particularly between the eyes and the nose. Merely creating a smaller device to fit into these restricted areas would defeat the purpose of having a general purpose application device for the larger flat areas of the face. 
         [0011]    Notwithstanding the teaching of the prior art, the ability to deliver cosmetic compounds into the skin by a general purpose device for both in small and restricted areas and the large flat areas of the face safely and effectively has remained unsolved. 
         [0012]    Responding to the above described unresolved needs, the object of this invention is to provide a general purpose skin care apparatus to safely increase the permeability of the stratum corneum and deliver cosmetic compounds deeply into the dermis in both the small and restricted areas and the large flat areas of the face. 
       SUMMARY OF THE INVENTION 
       [0013]    As noted in the description of the prior art, the safety of the typical sonophoresis apparatus is compromised by the high intensity requirements of the process, resulting in excessive tissue heating and its associated consequences. 
         [0014]    An objective of the invention is to improve the safety of typical sonophoresis apparatus to deliver cosmetic compounds into the dermis at reduced ultrasound intensity, particularly in small and restricted areas of the face, such as between the eyes and the nose. 
         [0015]    The invention achieves this objective of utilizing lower intensity ultrasonic pressure waves by augmenting the ultrasonic pressure waves with non-tissue heating low frequency sonic vibrations applied to the skin in combination with the high frequency ultrasound. The low frequency sonic vibration component of this new method increases the permeability of the skin and allows a lower intensity non-tissue heating ultrasound component to drive the cosmetic compound through the stratum corneum into the dermis. Furthermore, since oils and various contaminants on the skin can reduce the penetration of cosmetic compounds, an optional pre treatment skin-cleansing step is part of the disclosed method. To reach into small and restricted areas, the invention utilizes slim metallic ultrasound waveguides. 
         [0016]    In the above discussion, the terms cosmetic compounds and vasodilators includes but not limited to skin care products such as anti wrinkle lotions, moisturizers, antioxidant vitamins, alpha-hydroxyl acids, liposomes, collagen, elastin, hair growth and hair remover compounds and others. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  shows a longitudinal cross section of the invention consisting of the device handle, the motion transducer neck, the applicator portion including an ultrasonic transducer, the driving motor, electronic controls and battery. 
           [0018]      FIG. 2  shows the cross section of the neck of the device, which is configured to act as a motion transducer. 
           [0019]      FIG. 3A  shows the applicator head of the device in contact with the skin. 
           [0020]      FIG. 3B  illustrates the sonic frequency component of the device and its effects on the stratum corneum. 
           [0021]      FIG. 4  illustrates the simultaneous application of the sonic frequency vibration and ultrasound pressure wave components of the device and their combined effects on the stratum corneum. 
           [0022]      FIG. 5  shows a longitudinal cross section of an alternative configuration of the invention. 
           [0023]      FIG. 6  shows a removable applicator head designed for convex areas of the anatomy. 
           [0024]      FIG. 7A  shows a removable applicator head designed for concave areas of the anatomy. 
           [0025]      FIG. 7B  shows a removable applicator head designed for concave areas of the anatomy having an ultrasound waveguide. 
           [0026]      FIG. 8  shows a removable brush head for cleansing the skin. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]      FIG. 1  and  FIG. 2  show the invention of the ultrasonic cosmetic applicator  20  in a preferred configuration. The applicator  20  comprises a tubular shaped handle portion  22 , a neck portion  24 , and an applicator head portion  26  constructed of a rigid plastic material such as Acrylonitrile Butadiene Styrene (ABS), an ultrasound transducer  28 , a driving motor  30 , an eccentric weight  32  mounted on the output shaft of the driving motor  30 , an electronic module  36 , a battery pack  38 , and interconnecting wiring  40 . 
         [0028]    The ultrasound transducer  28  is typically constructed of a piezo-electric ceramic material such as PZT-8 grade Lead Zirconate Titanate manufactured by Morgan Matroc, Inc., or similar products manufactured by numerous other entities. The construction of the ultrasound transducer  28  can be a single or a multiple element unit, as it is commonly practiced by people familiar in the art. 
         [0029]    The ABS material utilized for the applicator  20  is due to the ABS excellent acoustic characteristics. However, numerous other rigid plastic materials could be substituted to achieve various cost and performance goals of the designers. 
         [0030]    Control switch  34  energizes the driving motor  30 , which rotates the eccentrically mounted weight  32  between 2,000 and 25,000 RPM, ideal speed being at 9,000 RPM, generating a 33 to 417 Hertz sonic frequency rotational vibration  44  of the handle  22  and neck  24  portions of the applicator  20 , which is considered a relatively low sonic frequency vibration in the art, which defines sonic frequency vibration as being 10 to 20,000 Hertz. As shown in  FIG. 2  the cross section of the neck  24  is designed to be relatively thin in the vertical direction X compared to the lateral direction Y thereby significantly increasing the vertical vibration  42  amplitude of the applicator head  26  while significantly decreasing lateral vibration  46  amplitude of the applicator head  26 . In other words, the neck portion  24  of the applicator  20  is designed to be a motion transducer to convert the rotational vibration  44  of the handle  22  portion of the applicator  20  into a substantially vertical vibration  42  of the applicator head  26 , converting the rotational energy of the motor  30  into vertically vibrating energy of the applicator head  26 . 
         [0031]    The battery pack  38  can be constructed as a single cell or multi cell battery pack, of various chemistries, such as Alkaline Manganese, Nickel-Cadmium, Ni-Mh, Lithium or other newer construction. 
         [0032]    The major function of the electronic module  36  is to convert the low voltage DC power, typically 1.5 to 4.8 VDC, of the battery pack  38  into high voltage (4.8 to 60 Volt) typically sinusoidal wave ultrasonic frequency (typically 15 kHz to 20 MHz) DC power in a continuous wave or burst wave modality. 
         [0033]    Simultaneously with energizing the driving motor  30 , switch  34  also activates the electronic module  36 . Through the interconnecting wiring  40  the electronic module  36  energizes the ultrasound transducer  28  which contracts and expands in tune with the high frequency DC power and converts this electronic power into ultrasonic pressure waves  48  at a typical intensity from 0.05 to 0.5 W/cm 2 . 
         [0034]    In  FIG. 3A  the applicator head  26  of the applicator  20  is shown in position on top of the outer surface of the stratum corneum  52 , consisting of flat dead cells filled with keratin fibers surrounded by ordered lipid bilayers  54 A shown in a relaxed position  58 . The ordered structure of the stratum corneum  52  and the ordered lipid bilayers  54 A are forming a normally almost impermeable skin structure. A thin layer of cosmetic compound  50  is shown to be disposed between the applicator contact surface  92  of the applicator head  26  and the stratum corneum  52 . A typically very limited amount of small molecules  56  of the cosmetic compound  50  are shown to be penetrating slightly into the ordered lipid bilayers  54 A without assistance from the applicator head  26 . 
         [0035]      FIG. 3B  shows the applicator head  26  activated in the vertically vibrating  42  mode on top of the stratum corneum  52  and a thin layer of cosmetic compound  50  is shown to be disposed between the applicator contact surface  92  of the applicator head  26  and the stratum corneum  52 . The vertical vibration  42  of the applicator head  26  (also depicted with solid and dashed lines to illustrate vibration) repeatedly compresses and relaxes the stratum corneum  52  and the ordered lipid bilayers  54 A from the relaxed position  58  to the compressed position  60  in tune with the high amplitude low frequency vibration mode of the applicator head  26 . Under the repeated and continuing influence of this high amplitude low sonic frequency vibration  42  and the resulting repeated compression and relaxation cycles of the stratum corneum  52  and the ordered lipid bilayers  54 A, the ordered lipid bilayers  54 A beginning to disorganize and develop larger passage ways for the molecules  56  of the cosmetic compound  50  to pass through. The disorganized lipid bilayers  54 B are depicted with dashed lines. 
         [0036]      FIG. 4  shows the applicator head  26  in contact with the stratum corneum  52  while having a thin layer of cosmetic compound  50  disposed between the applicator contact surface  92  of the applicator head  26  and the stratum corneum  52 . The ultrasound transducer  28  is shown being energized by the electronic module  36  through the connective wiring  40  and radiating ultrasonic pressure waves  48  into the stratum corneum  52  and the disorganized lipid bilayers  54 B. While the sonophoresis art has been demonstrated to work in the frequency range of 20 kHz to 20 MHz and in both of a continuous wave and a burst wave modality, it is important to select the right combination of frequency, driving voltage, and modality to match the size and characteristics of the piezo electric transducer selected for the system. Hard piezo materials such as the PZT8 formulation will output high ultrasonic power intensities with the associated heating of tissues when driven by high voltages. To avoid overheating the tissue, a 20% duty cycle (20% on 80% off) burst modality has been proven helpful in prior art. 
         [0037]    Now, according to the invention, safety of the sonophoresis process can be further enhanced by the simultaneous application of a non tissue heating high amplitude low sonic frequency mechanical vibration  42  and the ultrasonic pressure waves  48  to the stratum corneum  52 . Due to the presence of the high amplitude low sonic frequency vibration  42  applied to the stratum corneum  52 , which establishes the initial pathways through the stratum corneum  52 , the intensity of the ultrasonic pressure waves  48  can be reduced significantly, resulting in proportional reduction of tissue heating, while maintaining the effectiveness of the process. 
         [0038]    The high frequency ultrasonic pressure waves  48 , as shown in  FIG. 4 , penetrate the disorganized lipid bilayers  54 B much deeper than the lower sonic frequency vibrations  42  do. These ultrasonic pressure waves  48  in a preferred frequency range of 20 kHz to 2 MHz and in a 20% duty cycle burst modality are developing mild cavitation deep within the lipid bilayers  54 B resulting in microscopic air and/or vacuum pockets  66  which act to further break up the organized lipid bilayers  54 A shown in  FIG. 3A  into disorganized lipid bilayers  54 B, generating more and deeper passage ways for the cosmetic compound molecules  56  to penetrate through the stratum corneum  52 , through the disorganized lipid bilayers  54 B, through the bottom layer of the epidermis  62  and into the dermis  64 . 
         [0039]      FIG. 5  shows a longitudinal cross section of an alternative configuration of the invention wherein the applicator  80  comprises a tubular shaped handle portion  82  terminating in an angular applicator head portion  90  constructed of a rigid plastic material such as Acrylonitrile Butadiene Styrene (ABS), an ultrasound transducer  28 , a driving motor  30 , an eccentric weight  32  mounted on the output shaft of the driving motor  30 , an electronic module  36 , a battery pack  38 , and interconnecting wiring  40 . 
         [0040]    The ultrasound transducer  28  is typically constructed of a piezo-electric ceramic material such as PZT-8 grade Lead Zirconate Titanate manufactured by Morgan Matroc, Inc., or similar products manufactured by numerous other entities. The construction of the ultrasound transducer  28  can be a single or a multiple element unit, as it is commonly practiced by people familiar in the art. 
         [0041]    The ABS material utilized for the applicator  80  is due to the ABS excellent acoustic characteristics. However, numerous other materials could be substituted to achieve various cost and performance goals of the designers. For example, the applicator contact surface  92  may be constructed of stainless steel or other metallic material. 
         [0042]    Control switch  34  energizes the driving motor  30 , which rotates the eccentrically mounted weight  32  between 2,000 and 25,000 RPM, ideal speed being at 9,000 RPM, generating a 33 to 417 Hertz sonic frequency rotational vibration  44  of the handle portion  82  of the applicator  80 . 
         [0043]    The angular positioning  87  of the applicator contact surface  92  of the applicator head portion  90  acts as a motion transducer converting the rotational vibration  44  of the handle portion  82  into an angular rotational vibration  84  of the applicator contact surface  92  of the applicator head portion  90 . The angular rotational vibration  84  creates a two dimensional vibration motion of the applicator contact surface  92  in the directions of motion vector  86  and motion vector  88 . 
         [0044]    While  FIG. 5  depicts an angularly fixed applicator head portion  90  construction, applicator  80  can also be constructed having a user adjustable angular applicator head portion  90  wherein the user can vary the angular positioning  87  of the applicator contact surface  92  to increase or decrease the vibratory motion in the directions of motion vector  86  and motion vector  88 . A decreasing angle  87  will decrease the vibration amplitude of motion vector  88  and increase the vibration amplitude of motion vector  86 . 
         [0045]    The battery pack  38  can be constructed as a single cell or multi cell battery pack, of various chemistries, such as Alkaline Manganese, Nickel-Cadmium, Ni-Mh, Lithium or other newer construction. 
         [0046]    The major function of the electronic module  36  is to convert the low voltage DC power, typically 1.5 to 4.8 VDC, of the battery pack  38  into high voltage (4.8 to 60 Volt) typically sinusoidal wave ultrasonic frequency (typically 15 kHz to 20 MHz) DC power in a continuous wave or burst wave modality. 
         [0047]    Simultaneously with energizing the driving motor  30 , switch  34  also activates the electronic module  36 . Through the interconnecting wiring  40  the electronic module  36  energizes the ultrasound transducer  28  which contracts and expands in tune with the high frequency DC power and converts this electronic power into ultrasonic pressure waves  48  at a typical intensity from 0.05 to 0.5 W/cm 2 . 
         [0048]    The embodiment of the invention as applicator  80  depicted in  FIG. 5  functions the same way as the embodiment of the invention as applicator  20  depicted in  FIGS. 1, 2, 3A, 3B, and 4 . More particularly, the sonic frequency vibration of the applicator contact surface  92  of the applicator head portion  90  in the direction of motion vector  86  described in  FIG. 5  functions the same way as the sonic frequency vibration of the applicator contact surface  92  of applicator head portion  26  in the direction of motion vector  42  described in  FIG. 3B  and  FIG. 4 . The ultrasonic pressure waves  48  radiated from applicator  80  described in  FIG. 5  function the same way as the ultrasonic pressure waves  48  radiated from applicator head  26  described in  FIG. 4 . The underlying science of the two embodiments are identical. 
         [0049]      FIG. 6  shows a applicator head  98  designed to conduct the low frequency orbital vibration  84  and vibration motion vectors  86  and  88  and the ultrasound pressure waves  48  into the hard convex areas of the anatomy, such as the scalp, the elbows, and similar areas. 
         [0050]    The applicator contact surface  92  of the applicator head portion  90  as described earlier in  FIG. 5  is typically made of rigid or semi rigid material designed for soft flexible surfaces of the anatomy, such as the cheeks, where the anatomy conforms to the applicator contact surface  92  under slight pressure and transmission of the ultrasonic pressure waves  48  to the anatomy is easily achieved. However, when the flat rigid applicator contact surface  92  is applied to a hard convex area, such as the scalp, it results in a very small single point contact, which limits the transmission of the ultrasonic pressure waves to the anatomy. 
         [0051]    To maximize transmission of the ultrasonic pressure waves  48  to the hard convex areas of the anatomy the applicator head  98  is made of a flexible ultrasound conductive material such as silicone rubber and features a concave contact surface  96  which easily conforms to the anatomy under slight pressure. The thickness of the soft silicone rubber material at the central point must be minimized in the sub-millimeter region to minimize ultrasound attenuation losses by the soft silicone rubber material. To further assure excellent transmission of the ultrasound pressure waves  48  from the ultrasound transducer  28  to the applicator head  98  a slight coating of ultrasound conductive material such as water or contact gel can be applied between the applicator contact surface  92  and the removable applicator head  98 . 
         [0052]    The applicator head  98  design depicted in  FIG. 6  can be executed either as permanently fixed to the applicator  80  or constructed to be easily removable for replacement or exchange with other optional accessories of the device. 
         [0053]      FIG. 7A  shows a simple inexpensive cone shaped applicator head  100  designed for concave areas of the anatomy. Such small concave areas as between the eyes and the nose or between the cheeks and the nose are typically not accessible by the flat applicator contact surface  92  of the applicator head portion  90  of applicator  80  designed for larger soft surfaces of the anatomy. The applicator head  100  is constructed of flexible materials, such as flexible silicone rubber conducting the low frequency orbital vibration  84  and vibration motion vectors  86  and  88  and the ultrasound pressure waves  48  into these small concave areas. While the conical shape of the applicator head  100  allows the contact with the restricted areas, the ultrasound pressure waves  48  must travel through a long path of 20 mm or longer ultrasound attenuating flexible plastic material, which significantly attenuates the ultrasound pressure waves  48  emitted by transducer  28 , reducing the effectiveness of the device. 
         [0054]    The applicator head  100  design depicted in  FIG. 7A  can be executed either as permanently fixed to the applicator  80  or constructed to be easily removable for replacement or exchange with other optional accessories of the device. 
         [0055]      FIG. 7B  depicts a solution to the excessive ultrasound pressure waves  48  attenuation described in  FIG. 7A , which eliminates the attenuation of the ultrasound pressure waves  48  emitted by the ultrasound transducer  28  and allow the ultrasound pressure waves  48  to reach the small and restricted areas between the eyes and the nose practically un-attenuated. The invention employs a conically shaped non-attenuating ultrasound waveguide  122  insert within the applicator head  120  made of metal such as aluminum, titanium or similar metals in solid contact with the flat applicator surface  92  of the applicator head portion  90  of the device. Aluminum or titanium metal is preferred for the waveguide due to their light weight and their non-attenuating characteristic of the ultrasound pressure waves  48 . The waveguide  122  is a long aspect ratio design, typically having a ratio of 4 to 1 or larger between the length A and the tip diameter B. The larger base diameter of the waveguide  122  is designed to match the size of the ultrasound transducer  28  in the applicator head portion  90  of the device. Tip diameter B is typically ranges between 4 mm and 6 mm. The tapered construction of waveguide  122  focuses the acoustic energy from the larger ultrasound transducer  28  into the smaller tip diameter B and increases the efficiency of the device. 
         [0056]    The shell of the applicator head  120  surrounding and securing the metallic ultrasound waveguide  122  is typically made of a flexible material, such as silicone rubber to provide a pleasant tactile feeling for the user. Dimension C shown at the tip of the applicator head  120  should be minimized to 1 mm or less to reduce the attenuation of the ultrasound pressure waves  48  reaching the skin of the user. 
         [0057]    The applicator head  120  design depicted in  FIG. 7B  can be executed either as permanently fixed to the applicator  80  or constructed to be easily removable for replacement or exchange with other optional accessories of the device. 
         [0058]      FIG. 8  shows a removable cleansing brush head  112  installed on the applicator head portion  90  of applicator  80 . The brush head  112  is typically constructed of a semi rigid ABS plastic material housing multiple tufts of bristles  114 . As described in detail in  FIG. 5  the applicator motor  30  vibrates the applicator head portion  90  in an orbital vibration  84  pattern. This orbital vibration  84  is transferred to the brush head  112  and the plurality of bristle tufts  114 . When energized through the interconnecting wiring  40  the ultrasound transducer  28  generates and emits ultrasound pressure waves  48  which are conducted by the applicator contact surface  92  to the brush head  112  and the bristle tufts  114  and radiated from the bristle tufts  114  to the skin of the user. Applying slight pressure of the orbitally vibrating  84  bristle tufts  114  against the skin the user effectively cleansing the skin by the synergistic scrubbing action of the bristle tufts  114  and the ultrasound pressure waves  48  radiated by the bristle tufts  114 . 
         [0059]      FIG. 8  also shows an optional construction of the applicator head portion  90  incorporating a stainless still cup  110 . 
         [0060]    While the preceding description contains much specificity, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of preferred and additional embodiments thereof. Skilled artisans will readily be able to change dimensions, shapes, and construction materials of the various components described in the embodiments and adopt the invention to various types of sonic and ultrasonic energy applications. For example, additional removable and interchangeable applicators for enhanced cleansing of the skin such as sponges, cotton pads, lotion dispensers enhanced by the sonic and ultrasonic frequency motion of the applicator head are possible. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.