Patent Publication Number: US-9890944-B2

Title: Recessed light fixture

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority from a provisional application of U.S. Patent Application No. 62/009,393 filed on Jun. 9, 2014, entitled “THE METHOD FOR THE RECESSED LIGHTING FIXTURES WITH FIRE, ACOUSTICS, AND MOISTURE PROOF FUNCTION”, the entirety of which is incorporated by reference herein. 
    
    
     BACKGROUND 
     Technical Field 
     The disclosure relates to a recessed light fixture, and in particular to a recessed light fixture with an intumescent material. 
     Description of the Related Art 
     Recessed lighting fixtures are installed into apertures in building structures, wherein the apertures may be on a ceiling or in a roof space of the building structures. However, it is impossible to make the dimensions of the aperture fit the light fixtures perfectly. There is always a gap between the recessed lighting fixture and ceiling. The gap can result in a high risk. When a fire breaks out, the fire and high-temperature smoke flows into the gap and then crosses to other spaces to spread. 
     Furthermore, when recessed lighting fixtures are installed in a humid environment such as a kitchen or a bathroom, moisture can pass through the gap, and the moisture can corrode the electric cables and terminals, which can cause a short-circuit and hence fire risk. 
     In addition, sometimes wind can blow into the roof or top ceiling space at a very high pressure, and the air flows through the gap at high speeds, causing a whistling noise. This can be uncomfortable for residents. 
     Therefore, a recessed light fixture which is fire-proof, moisture-proof and sound-muffling is needed. 
     SUMMARY 
     The present disclosure provides a recessed light fixture, including: a casing having an inner wall and an outer wall to define a space; a front flange extending outward from the casing and surrounding the space, wherein the front flange has a top surface and a bottom surface; and an intumescent material disposed in a first recess of the outer wall and/or disposed on the top surface of the front flange. 
     A detailed description is given in the following embodiments with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure may be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein: 
         FIG. 1A  is a perspective view of a recessed light fixture when viewed from a tilted angle in accordance with some embodiments of the present disclosure; 
         FIG. 1B  is an exploded view of the recessed light fixture in  FIG. 1A ; 
         FIG. 1C  is a cross-sectional view of a recessed light fixture in accordance with some embodiments of the present disclosure; 
         FIG. 1D  is an enlarged figure of portion A of the recessed light fixture in  FIG. 1C ; 
         FIG. 1E  is a cross-sectional view of the recessed light fixture in accordance with some embodiments of the present disclosure after being installed in a building; 
         FIG. 1F  is an enlarged figure of portion A of the recessed light fixture in  FIG. 1E ; 
         FIG. 2  is a cross-sectional view of a recessed light fixture in accordance with another embodiment of the present disclosure; 
         FIG. 3A  is a top view of a recessed light fixture in accordance with a further embodiments of the present disclosure; 
         FIG. 3B  is a perspective view of the recessed light fixture in  FIG. 3A ; 
         FIGS. 4A-4D  are cross-sectional views of a recessed light fixture in accordance with some embodiments of the present disclosure; 
         FIGS. 5A-5B  are cross-sectional views of a recessed light fixture in accordance with another embodiment of the present disclosure; 
         FIG. 6A  is a cross-sectional view of a recessed light fixture in accordance with another embodiment of the present disclosure; 
         FIG. 6B  is a cross-sectional view of a recessed light fixture in accordance with another embodiment of the present disclosure; and 
         FIG. 7  is a cross-sectional view of a recessed light fixture in accordance with yet another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The recessed light fixture of the present disclosure are described in detail in the following description. In the following detailed description, for purposes of explanation, numerous specific details and embodiments are set forth in order to provide a thorough understanding of the present disclosure. The specific elements and configurations described in the following detailed description are set forth in order to clearly describe the present disclosure. It will be apparent, however, that the exemplary embodiments set forth herein are used merely for the purpose of illustration, and the inventive concept may be embodied in various forms without being limited to those exemplary embodiments. In addition, the drawings of different embodiments may use like and/or corresponding numerals to denote like and/or corresponding elements in order to clearly describe the present disclosure. However, the use of like and/or corresponding numerals in the drawings of different embodiments does not suggest any correlation between different embodiments. In addition, in this specification, expressions such as “one element disposed on/over one layer”, may indicate not only the direct contact of the two elements, but also, a non-contact state of the two elements. In the above situation, the two elements may not directly contact. 
     It should be noted that the elements or devices in the drawings of the present disclosure may be present in any form or configuration known to those skilled in the art. In addition, the expression “a layer overlying another layer”, “a layer is disposed above another layer”, “a layer is disposed on another layer” and “a layer is disposed over another layer” may indicate that the layer directly contacts the other layer, but it may also indicate that the layer does not directly contact the other layer, there being one or more intermediate layers disposed between the layer and the other layer. 
     In addition, in this specification, relative expressions are used. For example, “lower”, “bottom”, “higher” or “top” are used to describe the position of one element relative to another. It should be appreciated that if a device is flipped upside down, an element that is “lower” will become an element that is “higher”. 
     The terms “about” and “substantially” typically mean +/−20% of the stated value, more typically +/−10% of the stated value, more typically +/−5% of the stated value, more typically +/−3% of the stated value, more typically +/−2% of the stated value, more typically +/−1% of the stated value and even more typically +/−0.5% of the stated value. The stated value of the present disclosure is an approximate value. When there is no specific description, the stated value includes the meaning of “about” or “substantially”. 
     It should be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention. 
     Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. It should be appreciated that, in each case, the term, which is defined in a commonly used dictionary, should be interpreted as having a meaning that conforms to the relative skills and the background or the context of the present disclosure, and should not be interpreted in an idealized or overly formal manner unless so defined. 
     The present disclosure utilizes an intumescent material disposed in a recess to improve the fireproof ability of the recessed light fixture. In addition, the present disclosure also utilizes a barrier pad to give the recessed light fixture moisture-proofing and sound-proofing properties. 
     Referring to  FIGS. 1A-1D   FIG. 1A  is a perspective view of a recessed light fixture when viewed from a tilted angle in accordance with some embodiments of the present disclosure,  FIG. 1B  is an exploded view of the recessed light fixture in  FIG. 1A ,  FIG. 1C  is a cross-sectional view of this recessed light fixture, and  FIG. 1D  is an enlarged figure of portion A of the recessed light fixture in  FIG. 1C . As shown in these figures, the recessed light  100  includes a recessed light fixture  101  and a lamp  106 . The recessed light fixture  101  includes a casing  102  and a front flange  104 . The recessed lighting fixtures  101  may be installed into the aperture in a building  200  as shown in  FIGS. 1E and 1F .  FIG. 1E  is a cross-sectional view of the recessed light fixture  101  after being installed into the building  200 , and  FIG. 1F  is an enlarged figure of portion A of the recessed light fixture in  FIG. 1E . The building  200  may include, but is not limited to, a ceiling, a roof space, a wall, a floor, or any other structure which is suitable to have an aperture for installing the lighting fixtures. 
     The casing  102  is adapted to house the lamp  106 . The casing  102  having an inner wall  102 S 1  and an outer wall  102 S 2 , and the inner wall  102 S 1  defines a space  102 A. The front flange  104  extends outwardly from the casing  102  and surrounds the space  102 A. In addition, the front flange  104  has a top surface  104 S 1  and a bottom surface  104 S 2 . The lamp  106  is disposed within the space  102 A of the casing  102 . In addition, the lamp  106  may include a base  106 A and a light-emitting element  106 B. Further, a heat spreader  107  is provided to spread out the heat produced by the lamp  106 . The base  106 A is used to hold the light-emitting element  106 B. The light-emitting element  106 B may include, but is not limited to, a light emitting diode, a halogen lamp, or any other suitable lamp. 
     In addition, the outer wall  102 S 2  of the casing  102  has a first recess  108  which may be near the front flange  104 , and the front flange  104  includes a second recess  110  disposed on the top surface  104 S 1 . The first recess  108  may connect with the second recess  110  as shown in  FIG. 1C . The recessed light fixture  101  further includes an intumescent material  112  disposed in the first recess  108  and/or disposed on the top surface  104 S 1  of the front flange  104 . In particular, the intumescent material  112  is disposed in the first recess  108  of the outer wall  102 S 2  of the casing  102  and/or the second recess  110  of the top surface  104 S 1  of the front flange  104 . 
     For example, in one embodiment, referring to  FIGS. 1A-1C , the intumescent material  112  may include a first intumescent material  112 A and a second intumescent material  112 B. The first intumescent material  112 A is disposed in the first recess  108  of the outer wall  102 S 2 , and the second intumescent material  112 B is disposed in the second recess  110 . In addition, one side of the first intumescent material  112 A may directly contact the top surface  104 S 1  of the front flange  104 , and the second intumescent material  112 B may directly contact the first intumescent material  112 A, as shown in  FIG. 1C . 
     As shown in  FIG. 1F , by disposing the intumescent material  112 , which is fire protection material, in the recess such as the first recess  108  and/or the second recess  110 , the fireproof ability of the recessed light fixture  101  may be improved. Specifically, in the event of a fire, the intumescent material  112  (or the first intumescent material  112 A and the second intumescent material  112 B) may expand at its onset temperature to fill any gaps  204  between the recessed light fixture  101  and the building  200 . The gaps  204  refer to the region between the top surface  104 S 1  of the front flange  104  and the building  200  and the region between the outer wall  102 S 2  of the casing  102  and the building  200 . Note that the gap  204  between the top surface  104 S 1  of the front flange  104  and the building  200  is resulted from the irregularities  202  of the recessed light fixture  101 . Specifically, since the irregularities  202  of the recessed light fixture  101  merely contact the top surface  104 S 1  of the front flange  104  at several points rather than an entire surface, the gap  204  is formed therebetween. Note that the gap  204  is also formed outward and inward the plane of  FIG. 1F  at the region corresponding to the irregularities  202 . Hence, the first intumescent material  112 A and the second intumescent material  112 B provide an effective seal against the passage of fire and smoke. Besides, by disposing the first intumescent material  112 A in the first recess  108 , the damage and malfunction of the first intumescent material  112 A may be prevented when installing the recessed light fixture  101  into the building  200  and the fireproof ability of the recessed light fixture  101  may be ensured. 
     In addition, since the second intumescent material  112 B is closer to the fire in the event of a fire, the second intumescent material  112 B would be heated and expand more quickly than the first intumescent material  112 A and may also fill the gaps  204  between the recessed light fixture  101  and the building  200 . Therefore, the second intumescent material  112 B may further improve the fireproof ability of the recessed light fixture  101 . Alternatively, since the second intumescent material  112 B may fill the gaps  204  between the recessed light fixture  101  and the building  200  by itself, the second intumescent material  112 B itself alone may also provide the fireproof ability of the recessed light fixture  101 . 
     The intumescent material  112  may include, but is not limited to, graphite-based intumescent material, silicone-based intumescent material, mastic-based intumescent material, organic-based intumescent material or water-based intumescent material, or any other suitable intumescent material, or a combination thereof. For example, one suitable intumescent material is a (preferably non-alkaline) fibreglass containing intumescent sheet material, including 50 wt % of ceramic fibre, 10 wt % of organic fibre, 10 wt % of adhesive and 30 wt % of intumescent, and the intumescent material may be doped with SiO 2 , Al 2 O 3 , CaO, MgO and B 2 O 3 . 
     In addition, the onset temperature of the intumescent material  112  is 100° C. or higher. For example, the onset temperature of the intumescent material  112  is 150° C. or higher. The onset temperature is the temperature at which the intumescent material  112  begins to expand. In addition, the free expansion ratio of the intumescent material  112  is 20:1 or higher. For example, the free expansion ratio of the intumescent material  112  is 50:1, 60:1 or higher. It should be noted that, if the free expansion ratio of the intumescent material  112  is too low, for example, lower than 20:1, the expanded intumescent material  112  cannot effectively fill the gaps  204  between the recessed light fixture  101  and the building  200  in the event of a fire, which in turn makes the recessed light fixture  101  unable to stop the fire or smoke from spreading. The free expansion ratio of the intumescent material refers to the expansion ratio of the intumescent material without any obstruction. In other words, if an intumescent material has a free expansion ratio of 20:1, it means the intumescent material is able to expand to fill  20  times its own initial volume when exposed to the heat of a fire without any obstruction. 
     Referring to  FIG. 1C , the recessed light  100  may further include a gap  114  between the wall  106 W of the lamp  106  and the inner wall  102 S 1  of the casing  102 . An intumescent glue  116  may be partially filled into the gap  114  to further improve the fireproof ability of the recessed light  100 . Specifically, in the event of a fire, the casing  102  may be melted due to the heat of the fire. The fire and high-temperature smoke will flow into the gap  114  between the lamp  106  and the casing  102  and then cross to the other space to spread the fire. Therefore, by putting the intumescent glue  116  in the gap  114 , the intumescent glue  116  may expand in the event of a fire to completely fill the gap  114  and stop the fire and high-temperature smoke from flowing into the gap  114 . Therefore, the intumescent glue  116  may further improve the fireproof ability of the recessed light  100 . 
     The intumescent glue  116  may include, but is not limited to, graphite-based intumescent material, silicone-based intumescent material, mastic-based intumescent material, organic-based intumescent material or water-based intumescent material, or any other suitable intumescent material, or a combination thereof. For example, one suitable intumescent material is a (preferably non-alkaline) fibreglass containing intumescent sheet material, including 50 wt % of ceramic fibre, 10 wt % of organic fibre, 10 wt % of adhesive and 30 wt % of intumescent, and the intumescent material may be doped with SiO 2 , Al 2 O 3 , CaO, MgO and B 2 O 3 . 
     As illustrated in  FIGS. 1A and 1B , the recessed light fixture  101  may further include a barrier pad  118  disposed in the second recess  110 . According to the aforementioned description, when the recessed lighting fixtures  101  are installed in a humid environment such as a kitchen or a bathroom, moisture will pass through gaps  204  between the recessed light fixture  101  and the building  200 , and then the moisture can corrode the electric cables and terminals, which can cause a short-circuit and fire risk. By disposing a barrier pad  118  in the second recess  110 , the moisture may be prevented from passing through the gaps  204  between the recessed light fixture  101  and the building  200  and the risk of fire may be lowered. 
     In addition, the air flowing through the gaps  204  at high wind speed would make big noise. The barrier pad  118  in the second recess  110  may also prevent the air from flowing through the gaps  204 , and thus lower the noise. Therefore, the barrier pad  118  in the second recess  110  of the present disclosure may give the recessed light fixture  101  moisture-proofing and sound-proof ability and may lower the risk of fire. The material of the barrier pad  118  may include, but is not limited to, polymer, synthetic rubber, or any other suitable barrier material, or a combination thereof. 
     In one embodiment, referring to  FIG. 1C  or  FIG. 1D , the barrier pad  118  is directly disposed over the second intumescent material  112 B in the second recess  110 . The second intumescent material  112 B and the barrier pad  118  are both in direct contact with the inner wall  104 S 3  in the second recess  110  of the front flange  104 . In addition, the barrier pad  118  is not in contact with the first intumescent material  112 A. In other words, the barrier pad  118  does not completely cover all top surface of the second intumescent material  112 B, and a portion of the second intumescent material  112 B is exposed from the barrier pad  118 , as shown in  FIG. 1C  or  FIG. 1D . Since the intumescent material  112  such as the second intumescent material  112 B needs space to initiate expansion, if the barrier pad  118  completely covers all top surface of the second intumescent material  112 B, the second intumescent material  112 B may not be able to successfully initiate the expansion. Therefore, the exposure of the second intumescent material  112 B from the barrier pad  118  can help the second intumescent material  112 B initiate the expansion successfully. 
     Similarly, in one embodiment, the first intumescent material  112 A does not completely fill the first recess  108 . A space is left in the first recess  108  to make the first intumescent material  112 A be able to initiate the expansion successfully, as shown in  FIG. 1C . 
     It should be noted that, although the barrier pad is directly disposed over the second intumescent material in the embodiments shown in  FIGS. 1A and 1B , those skilled in the art will appreciate that other configurations of the barrier pad and the intumescent material may also be applicable. This will be described in detail in the following description. Therefore, the exemplary embodiments set forth in  FIGS. 1A and 1B  are merely for the purpose of illustration, and the inventive concept may be embodied in various forms without being limited to the exemplary embodiments as shown in  FIGS. 1A and 1B . 
     Referring to  FIG. 2 , which is a cross-sectional view of a recessed light fixture in accordance with another embodiment of the present disclosure. Note that the same or similar elements or layers corresponding to those of the recessed light fixture are denoted by like reference numerals. The same or similar elements or layers denoted by like reference numerals have the same meaning and will not be repeated for the sake of brevity. 
     Unlike the embodiment shown in  FIGS. 1A and 1B , the barrier pad  118  in  FIG. 2  does not contact the intumescent material  112  such as the second intumescent material  112 B, and is not directly disposed over the second intumescent material  112 B, as shown in the embodiments shown in  FIGS. 1A and 1B . In  FIG. 2 , the barrier pad  118  and the second intumescent material  112 B surround the casing. Besides, one side of the barrier pad  118  directly contacts the inner wall  104 S 3  of the front flange  104 , and the other side of the barrier pad  118  is spaced apart from the second intumescent material  112 B by a distance in the second recess  110 . Since the second intumescent material  112 B is not covered by the barrier pad  118 , the second intumescent material  112 B has sufficient space to initiate the expansion. Therefore, this configuration shown in  FIG. 2  may further improve the fireproof ability of the recessed light fixture  101 . 
       FIG. 3A  is a top view of a recessed light fixture in accordance with a further embodiments of the present disclosure.  FIG. 3B  is a perspective view of the recessed light fixture in  FIG. 3A . As shown in these figures, the barrier pad  118  may include a plurality of cuts  118 R at an inner side  118 S 1  of the barrier pad  118 . In particular, the barrier pad  118  has an inner portion  118 A and an outer portion  118 B which are divided by the dotted line  118 C located at about 50% width of the barrier pad  118 . The inner portion  118 A is the portion of the barrier pad  118  inside the dotted line  118 C and closer to the casing  102 , whereas the outer portion  118 B is the portion of the barrier pad  118  outside the dotted line  118 C and closer to the inner wall  104 S 3  of the front flange  104 . The plurality of the cuts  118 R is disposed at the inner portion  118 A of the barrier pad  118 . 
     As shown in  FIG. 3A , the cuts  118 R may further expose the underlying second intumescent material  112 B. Therefore, the second intumescent material  112 B may initiate the expansion more successfully due to the cuts  118 R, and the fireproof ability of the recessed light fixture  101  may be further improved. In addition, since the cuts  118 R expose specific portions of the underlying second intumescent material  112 B, the cuts  118 R may be used to control which portion of the second intumescent material  112 B is used to initiate the expansion. 
     In addition, the plurality of the cuts  118 R may have a triangular shape, a semicircular shape, a rectangular shape, a trapezoidal shape, or a shape of any other suitable shape, as shown in  FIG. 3A . The area ratio of the plurality of the cuts  118 R to the barrier pad  118  without the cuts  118 R may range from about 5% to 30%, for example from about 10% to 20%. It should be noted that, if the area ratio of the plurality of the cuts  118 R to the barrier pad  118  without the cuts  118 R is too large, for example greater than 30%, the area of the barrier pad  118  having the cuts  118 R would be too small and thus the barrier pad  118  cannot effectively prevent the moisture and air from passing through the gaps  204  between the recessed light fixture and the building  200 . However, if the area ratio of the plurality of the cuts  118 R to the barrier pad  118  without the cuts  118 R is too small, for example smaller than 5%, the cuts  118 R cannot effectively improve the fireproof ability of the recessed light fixture  101 . 
     As seen in  FIG. 3A , the barrier pad  118  may further include at least one annular protrusion  118 P. In particular, the annular protrusion  118 P is disposed at the outer portion  118 B of the barrier pad  118 . Since the annular protrusion  118 P protrudes upward from the surface of the barrier pad  118 , it may further fill the gaps  204  between the recessed light fixture  101  and the building  200  and may further prevent moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . Therefore the risk of fire may be further decreased and noise may be further reduced. 
       FIGS. 4A-4D  are cross-sectional views of a recessed light fixture  101  in accordance with some embodiments of the present disclosure. Note that the casing  102  and the lamp  106  are omitted in  FIGS. 4A-4D  for the sake of brevity. As shown in  FIGS. 4A-4D , the annular protrusion  118 P may have a triangular cross-section, a semicircular cross-section, a rectangular cross-section, a trapezoidal cross-section, or a cross-section of any other suitable shape. 
     Still referring to  FIGS. 4A-4D , the pitch P between any two of the plurality of annular protrusions  118 P may range from about 0.3 mm to 1 mm, for example from about 0.5 mm to 0.7 mm. It should be noted that, if the pitch P is too large, for example greater than 1 mm, the annular protrusion  118 P cannot effectively prevent moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . 
     In addition, the distance D from an edge of one annular protrusion  118 P to an edge of an adjacent annular protrusion  118 P may range from about 0.2 mm to 0.8 mm, for example from about 0.3 mm to 0.7 mm. It should be noted that, if the distance D is too large, for example greater than 0.8 mm, the annular protrusion  118 P cannot effectively prevent the moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . 
     Still referring to  FIGS. 4A-4D , the width W of the annular protrusion  118 P may range from about 0.1 mm to 0.4 mm, for example from about 0.2 mm to 0.3 mm. It should be noted that, if the width W is too great, for example greater than 0.4 mm, the annular protrusion  118 P cannot effectively prevent the moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . 
     In addition, the height H of the annular protrusion  118 P may range from about 0.1 mm to 1 mm, for example from about 0.3 mm to 0.7 mm. It should be noted that, if the height H is too small, for example smaller than 0.1 mm, the annular protrusion  118 P cannot effectively prevent the moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . 
       FIGS. 5A-5B  are cross-sectional views of a recessed light fixture  101  in accordance with some embodiment of the present disclosure. In one embodiment, as shown in  FIG. 5A , the heights H of the plurality of the annular protrusions  118 P may decrease from a periphery  120  (or the outer side  118 S 2 ) of the barrier pad  118  to a center  122  (or the inner side  118 S 1 ) of the barrier pad  118 . This height variation of the annular protrusions  118 P may further prevent the moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . Therefore the risk of fire may be further decreased and the noise may be further reduced. 
     In another embodiment, as shown in  FIG. 5B , the heights H of the plurality of annular protrusions  118 P may increase from a periphery  120  (or the outer side  118 S 2 ) of the barrier pad  118  to a center  122  (or the inner side  118 S 1 ) of the barrier pad  118 . This height variation of the annular protrusions  118 P may also further prevent the moisture and air from passing through the gaps  204  between the recessed light fixture  101  and the building  200 . Therefore the risk of fire may be further decreased and the noise may be further reduced. 
     It should be noted that, although the barrier pad  118  includes only three annular protrusions  118 P in the embodiments shown in  FIGS. 5A and 5B , those skilled in the art will appreciate that the barrier pad may include one, two or more than three annular protrusions. Therefore, the exemplary embodiments set forth in  FIGS. 5A and 5B  are merely for the purpose of illustration, and the inventive concept may be embodied in various forms without being limited to the exemplary embodiments as shown in  FIGS. 5A and 5B . 
     It should be noted that, although the recessed light fixture includes the first intumescent material and the second intumescent material in the embodiments shown in  FIGS. 1A-5B , those skilled in the art will appreciate that the recessed light fixture may include only the first intumescent material or only the second intumescent material in other embodiments. This will be described in detail in the following description. Therefore, the exemplary embodiments set forth in  FIGS. 1A-5B  are merely for the purpose of illustration, and the inventive concept may be embodied in various forms without being limited to the exemplary embodiments as shown in  FIGS. 1A-5B . 
       FIG. 6A  is a cross-sectional view of a recessed light fixture  101  in accordance with another embodiment of the present disclosure. Note that the same or similar elements or layers corresponding to those of the recessed light fixture are denoted by like reference numerals. The same or similar elements or layers denoted by like reference numerals have the same meaning and will not be repeated for the sake of brevity. 
     The difference between the embodiment shown in  FIG. 6A  and the embodiment shown in  FIGS. 1A-5B  is that the recessed light fixture  101  only includes the first intumescent material  112 A, and does not include the second intumescent material. In addition, the barrier pad  118  directly contacts the top surface  104 S 1  and the inner wall  104 S 3  of the front flange  104 . 
     Next, referring to  FIG. 6B , which is a cross-sectional view of a recessed light fixture  101  in accordance with another embodiment of the present disclosure. The difference between the embodiment shown in  FIG. 6B  and the embodiments shown in  FIGS. 1A-6A  is that the recessed light fixture  101  only includes the second intumescent material  112 B, and does not include the first intumescent material  112 A. In addition, the second intumescent material  112 B directly contacts the first recess  108 . 
     It should be noted that, although the top surface of the front flange is substantially perpendicular to the outer wall of the casing in the embodiments shown in  FIGS. 1A-6B , those skilled in the art will appreciate that the top surface of the front flange may intersect the outer wall of the casing at an acute angle. This will be described in detail in the following description. Therefore, the exemplary embodiments set forth in  FIGS. 1A-6B  is merely for the purpose of illustration, and the inventive concept may be embodied in various forms without being limited to the exemplary embodiments as shown in  FIGS. 1A-6B . 
       FIG. 7  is a cross-sectional view of a recessed light fixture  101  in accordance with another embodiment of the present disclosure. In this embodiment, the top surface  104 S 1  of the front flange  104  intersects the outer wall  102 S 2  of the casing  102  at an acute angle θ, rather than being perpendicular to the outer wall  102 S 2  of the casing  102  as in the embodiments of  FIGS. 1A-2 and 6A-6B . 
     It will be appreciated that, while the examples show the casing or the recessed light fixture having a generally circular cylindrical tubular shape, this is not essential. Any form of casing or recessed light fixture may be used. 
     In summary, the present disclosure utilizes the intumescent material disposed in the recess to improve the fireproof ability of the recessed light fixture. In addition, the present disclosure also utilizes the barrier pad to prevent the moisture and air from passing through the gaps or irregularities between the recessed light fixture and the building. Therefore the risk of fire may be further decreased and the noise may be further reduced. 
     Although some embodiments of the present disclosure and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. For example, it will be readily understood by those skilled in the art that many of the features, functions, processes, and materials described herein may be varied while remaining within the scope of the present disclosure. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.