以下,對於本發明之實施形態詳細地說明。 冷凍機油於100℃下之動黏度為0.5 mm2
/s以上且1.5 mm2
/s以下。冷凍機油於100℃下之動黏度就耐磨耗性與冷凍機之省能量化之平衡進而優異之觀點而言,較佳為0.6 mm2
/s以上且1.4 mm2
/s以下,更佳為0.8 mm2
/s以上且1.3 mm2
/s以下,進而較佳為1.0 mm2
/s以上且1.3 mm2
/s以下。本發明之動黏度意指基於JIS K2283:2000所測定之動黏度。 冷凍機油於40℃下之動黏度例如亦可為2.0 mm2
/s以上,為2.5 mm2
/s以上,或為2.8 mm2
/s以上,例如亦可為4.5 mm2
/s以下,為4.0 mm2
/s以下,或為3.5 mm2
/s以下。 冷凍機油之苯胺點為70℃以上,就耐磨耗性進而優異之觀點而言,較佳為73℃以上,更佳為76℃以上,進而較佳為80℃以上。又,若苯胺點為70℃以上,則有極壓劑之效果變好之傾向。冷凍機油之苯胺點就與用於冷凍裝置(冷凍機)內之PET(聚對苯二甲酸乙二酯)材料、密封材料等有機材料之適合性之觀點而言,較佳為100℃以下,更佳為95℃以下,進而較佳為90℃以下。本發明之苯胺點意指基於JIS K2256:2013所測定之值。 冷凍機油之藉由氣相層析法蒸餾之蒸餾性狀就冷凍機油之低黏度化與潤滑性之平衡進而優異,進而將引火點維持為較高之觀點而言,較佳為一面提高低沸點側之蒸餾溫度,一面將高沸點側之蒸餾溫度維持為適當之範圍。此種冷凍機油較理想為具有以下說明之蒸餾性狀。 冷凍機油之初餾點(IBP)例如亦可為200℃以上,為220℃以上,或為230℃以上,例如亦可為260℃以下,為250℃以下,或為240℃以下。 冷凍機油之5%蒸餾溫度T5
例如亦可為205℃以上,為225℃以上,或為235℃以上,例如亦可為265℃以下,為255℃以下,或為245℃以下。 冷凍機油之10%蒸餾溫度T10
例如亦可210℃以上,為230℃以上,或為235℃以上,例如亦可為270℃以下,為260℃以下,或為250℃以下。 冷凍機油之50%蒸餾溫度T50
例如亦可為230℃以上,為250℃以上,或為260℃以上,例如亦可為300℃以下,為280℃以下,或為270℃以下。 冷凍機油之70%蒸餾溫度T70
就潤滑性與高引火點之觀點而言,較佳為250℃以上,更佳為260℃以上,進而較佳為270℃以上。冷凍機油之70%蒸餾溫度T70
就低黏度化之觀點而言,較佳為未達330℃,更佳為未達300℃,進而較佳為295℃以下,尤佳為290℃以下。 冷凍機油之90%蒸餾溫度T90
就耐磨耗性進而優異之觀點而言,較佳為280℃以上且未達360℃,更佳為290℃以上且355℃以下,亦可為280℃以上且未達350℃,為290℃以上且345℃以下,為300℃以上且340℃以下,或為300℃以上且330℃以下。 冷凍機油之95%蒸餾溫度T95
例如為290℃以上,為310℃以上,或為330℃以上,例如亦可為390℃以下,為385℃以下,為370℃以下,為360℃以下,或為350℃以下。 冷凍機油之蒸餾終點EP就潤滑性之觀點而言,較佳為390℃以上,更佳為395℃以上,進而較佳為400℃以上。冷凍機油之蒸餾終點EP就低黏度化之觀點而言,較佳為440℃以下,更佳為430℃以下,進而較佳為425℃以下,亦可為420℃以下,為415℃以下,或為410℃以下。蒸餾終點EP較佳為390℃以上且440℃以下,更佳為390℃以上且430℃以下,進而較佳為390℃以上且425℃以下,尤佳為395℃以上且425℃以下,亦可為390℃以上且420℃以下,為395℃以上且410℃以下,或為400℃以上且415℃以下。 就冷凍機油之低黏度化與潤滑性之平衡進而優異,進而將引火點維持為較高之觀點而言,較佳為如上所述般,一面提高低沸點側之蒸餾溫度,一面將高沸點側之蒸餾溫度維持為適當之範圍。除上述外,較理想為與其增大蒸餾範圍,不如如下般維持為適度狹窄之範圍且不過於狹窄之範圍。 冷凍機油之初餾點IBP與95%蒸餾溫度T95
之差(T95
-IBP)較佳為60℃以上,更佳為70℃以上,進而較佳為80℃以上。冷凍機油之初餾點IBP與95%蒸餾溫度T95
之差(T95
-IBP)較佳為160℃以下,更佳為150℃以下,進而較佳為140℃以下,尤佳為130℃以下。初餾點IBP與95%蒸餾溫度T95
之差(T95
-IBP)較佳為60℃以上且160℃以下,更佳為60℃以上且150℃以下,較佳為70℃以上且150℃以下,亦可為70℃以上且140℃以下,或為80℃以上且130℃以下。 冷凍機油之蒸餾終點EP與90%蒸餾溫度T90
之差(EP-T90
)就潤滑性之觀點而言,較佳為40℃以上,更佳為50℃以上,進而較佳為55℃以上,亦可為60℃以上,較佳為140℃以下,更佳為130℃以下,進而較佳為120℃以下。冷凍機油之蒸餾終點EP與90%蒸餾溫度T90
之差(EP-T90
)較佳為40℃以上且140℃以下,更佳為50℃以上且130℃以下,進而較佳為55℃以上且120℃以下,亦可為60℃以上且120℃以下。 冷凍機油之95%蒸餾溫度T95
與90%蒸餾溫度T90
之差(T95
-T90
)就潤滑性之觀點而言,較佳為3℃以上,更佳為10℃以上,進而較佳為20℃以上,尤佳為25℃以上,亦可為30℃以上,較佳為80℃以下,更佳為70℃以下,進而較佳為60℃以下。95%蒸餾溫度T95
與90%蒸餾溫度T90
之差(T95
-T90
)較佳為3℃以上且80℃以下,更佳為10℃以上且80℃以下,進而較佳為20℃以上且70℃以下,尤佳為25℃以上且60℃以下,亦可為30℃以上且60℃以下。 本發明之初餾點、5%蒸餾溫度、10%蒸餾溫度、50%蒸餾溫度、70%蒸餾溫度、90%蒸餾溫度、95%蒸餾溫度及蒸餾終點分別意指依據ASTM D7213-05中規定之藉由氣相層析法之蒸餾試驗方法所測定之初餾點、5(容量)%蒸餾溫度、10(容量)%蒸餾溫度、50(容量)%蒸餾溫度、70(容量)%蒸餾溫度、90(容量)%蒸餾溫度、95(容量)%蒸餾溫度及蒸餾終點。 冷凍機油於20℃下之折射率就冷凍機油之低黏度化與潤滑性之平衡進而優異,進而將引火點維持為較高之觀點而言,例如亦可為1.440以上,為1.445以上,或為1.450以上,例如亦可為1.470以下,為1.465以下,或為1.460以下。本發明之折射率意指依據JIS K0062:1992於20℃下所測定之折射率。 冷凍機油於15℃下之密度就冷凍機油之低黏度化與潤滑性之平衡進而優異,進而將引火點維持為較高之觀點而言,亦可較佳為0.86 g/cm3
以下,更佳為0.85 g/cm3
以下,進而較佳為0.84 g/cm3
以下,例如亦可為0.81 g/cm3
以上,為0.815 g/cm3
以上。本發明之密度意指依據JIS K2249:2011於15℃下所測定之密度。 冷凍機油之硫分並無特別限制,就穩定性及與金屬材料之適合性優異之觀點而言,較佳為0.001質量%以上,亦可為0.02質量%以上,或為0.3質量%以下,為0.1質量%以下或為0.05質量%以下。於本實施形態中,冷凍機油於將下述之極壓劑添加例如0.2質量%以上之情形時,冷凍機油之硫分亦可為未達0.05質量%,為未達0.02質量%,為未達0.01質量%或未達0.005質量%。本發明之硫分意指JIS K2541-6:2013中規定之藉由紫外線螢光法所測定之硫分。 冷凍機油或其中所含之潤滑油基油之藉由環分析之組成比率就冷凍機油之低黏度化與潤滑性之平衡進而優異,進而將引火點維持為較高之觀點而言,較佳為以下所示之範圍。 冷凍機油或其中所含之潤滑油基油之%CP
較佳為40以上,更佳為42以上,更佳為44以上,較佳為60以下,更佳為57以下,進而較佳為54以下。冷凍機油或其中所含之潤滑油基油之%CP
較佳為40以上且60以下,更佳為42以上且57以下,進而較佳為44以上且54以下。 冷凍機油或其中所含之潤滑油基油之%CN
較佳為40以上,更佳為42以上,進而較佳為44以上,較佳為65以下,更佳為60以下,進而較佳為57以下,尤佳為54以下。冷凍機油或其中所含之潤滑油基油之%CN
較佳為40以上且65以下,更佳為42以上且60以下,進而較佳為44以上且57以下,尤佳為44以上且54以下。 冷凍機油或其中所含之潤滑油基油之%CP
相對於%CN
之比(%CP
/%CN
)較佳為0.6以上,更佳為0.7以上,進而較佳為0.8以上,較佳為1.4以下,更佳為1.3以下,進而較佳為1.2以下。冷凍機油或其中所含之潤滑油基油之%CP
相對於%CN
之比(%CP
/%CN
)較佳為0.6以上且1.4以下,更佳為0.7以上且1.3以下,進而較佳為0.8以上且1.2以下。 冷凍機油或其中所含之潤滑油基油之%CA
就潤滑性或穩定性之觀點而言,亦可較佳為5以下,更佳為3以下,進而較佳為2以下,亦可為0,亦可較佳為0.5以上,為1以上。 本發明之%CP
、%CN
及%CA
分別意指藉由依據ASTM D3238-95(2010)之方法(n-d-M環分析)所測定之值。 冷凍機油之引火點就安全性之觀點而言,較佳為110℃以上,更佳為120℃以上,尤佳為130℃以上,為了使40℃下之動黏度成為2~4 mm2
/s左右之低黏度油,較佳為155℃以下,更佳為145℃以下。本發明下之引火點意指依據JIS K2265-4:2007(克氏開杯式(COC)法)所測定之引火點。 冷凍機油之流動點例如亦可為-10℃以下,或為-20℃以下,亦可為-50℃以下,但就精製成本之觀點而言,亦可為-40℃以上。本發明之流動點意指依據JIS K2269:1987所測定之流動點。 冷凍機油之酸值例如亦可為1.0 mgKOH/g以下,或為0.1 mgKOH/g以下。本發明之酸值意指依據JIS K2501:2003所測定之酸值。 冷凍機油之體積電阻率例如亦可為1.0×109
Ω・m以上,為1.0×1010
Ω・m以上,或為1.0×1011
Ω・m以上。本發明之體積電阻率意指依據JIS C2101:1999所測定之25℃下之體積電阻率。 冷凍機油之水分含量係以冷凍機油總量基準計,例如亦可為200 ppm以下,為100 ppm以下,或為50 ppm以下。 冷凍機油之灰分例如亦可為100 ppm以下,或為50 ppm以下。本發明之灰分意指依據JIS K2272:1998所測定之灰分。 冷凍機油係具有如下性狀之冷凍機油:於一實施形態中,上述之性狀中,至少100℃下之動黏度為0.5 mm2
/s以上且1.5 mm2
/s以下,藉由氣相層析法蒸餾之90%蒸餾溫度為280℃以上且未達360℃,苯胺點為70℃以上。冷凍機油係具有如下性狀之冷凍機油:於另一實施形態中,上述之性狀中,至少100℃下之動黏度為0.5 mm2
/s以上且1.5 mm2
/s以下,藉由氣相層析法蒸餾之70%蒸餾溫度為270℃以上且未達300℃,苯胺點為70℃以上。 具有如上所述之性狀之冷凍機油含有例如潤滑油基油與潤滑油添加劑。潤滑油基油例如可列舉:礦物油。礦物油可藉由使將石蠟系、環烷系等原油進行常壓蒸餾及減壓蒸餾所獲得之潤滑油蒸餾分利用脫溶劑、溶劑精製、加氫精製、加氫裂解、溶劑脫蠟、加氫脫蠟、白土處理、硫酸洗淨等方法進行精製而獲得。該等精製方法可單獨使用一種,亦可將兩種以上組合而使用。作為潤滑油基油,就獲取性之觀點而言,較佳為使用適宜選擇通常用於溶劑、稀釋劑、金屬加工油等用途之低黏度之潤滑油基油者。 為了製造具有如上所述之性狀之冷凍機油,關於成為主成分(例如90質量%以上)之潤滑油基油之性狀,只要於本說明書中並無特別規定,則較理想為與上述同等。因此,雖然於上述中對於冷凍機油之各項目之性狀顯示較佳之範圍,但只要於本說明書中並無規定,則亦可改稱為關於冷凍機油中所含之潤滑油基油之各項目之較佳之範圍。 潤滑油基油之硫分並無特別限制,但就穩定性及與金屬材料之適合性優異之觀點而言,較佳為0.001質量%以上,為0.02質量%以上,或為0.3質量%以下,亦可為0.1質量%以下或為0.05質量%以下。於本實施形態中,冷凍機油於添加下述之極壓劑例如0.2質量%以上之情形時,潤滑油基油之硫分亦可為未達0.05質量%,為未達0.02質量%,為未達0.01質量%或未達0.005質量%。 潤滑油基油亦可包含上述礦物油,通常以潤滑油基油總量基準計,礦物油之比率亦可為50質量%以上,較佳為70質量%以上,尤佳為90質量%以上,只要不明顯阻礙本發明之效果,除上述礦物油以外,亦可進而含有烷基苯等烴油、或酯等含氧油。 烷基苯亦可為選自由下述烷基苯(a1)及烷基苯(a2)所組成之群中之至少一種。 烷基苯(a1):具有1~4個碳數1~19之烷基,且該烷基之合計碳數為9~19之烷基苯(較佳為具有1~4個碳數1~15之烷基,且烷基之合計碳數為9~15之烷基苯) 烷基苯(a2):具有1~4個碳數1~40之烷基,且該烷基之合計碳數為20~40之烷基苯(較佳為具有1~4個碳數1~30之烷基,且烷基之合計碳數為20~30之烷基苯) 酯例如亦可為一元醇或二元醇與脂肪酸之酯。一元醇或二元醇例如亦可為碳數4~12之脂肪族醇。脂肪酸例如亦可為碳數4~18之脂肪酸。 潤滑油基油於40℃下之動黏度例如亦可為2.0 mm2
/s以上,為2.5 mm2
/s以上,或為2.8 mm2
/s以上,例如亦可為4.5 mm2
/s以下,為4.0 mm2
/s以下,或為3.5 mm2
/s以下。潤滑油基油於100℃下之動黏度例如亦可為0.5 mm2
/s以上,為0.6 mm2
/s以上,為0.8 mm2
/s以上,或為1.0 mm2
/s以上,例如亦可為1.5 mm2
/s以下,為1.4 mm2
/s以下,或為1.3 mm2
/s以下。 潤滑油基油之含量係以冷凍機油總量基準計,亦可為50質量%以上,為60質量%以上,為70質量%以上,為80質量%以上,為90質量%以上,或為95質量%以上。 作為潤滑油添加劑,例如可列舉:酸捕捉劑、抗氧化劑、極壓劑、油性劑、消泡劑、金屬減活劑、耐磨耗劑、黏度指數提高劑、降流動點劑、淨化分散劑等。該等添加劑之含量以冷凍機油總量基準計,亦可為10質量%以下或5質量%以下。 冷凍機油基於上述之添加劑中,耐磨耗性亦進而優異之觀點而言,較佳為含有極壓劑。作為較佳之極壓劑,可列舉:磷系極壓劑。磷系極壓劑例如可列舉:磷酸酯、酸性磷酸酯、酸性磷酸酯之胺鹽、氯化磷酸酯、亞磷酸酯、硫代磷酸酯等。磷酸酯較佳為三苯基磷酸酯(TPP)或磷酸三甲苯酯(TCP)。磷系極壓劑之含量係以冷凍機油總量基準計,例如亦可為0.2質量%以上,較佳為0.5~5質量%,更佳為1~4質量%,尤佳為1.5~3質量%。若使用苯胺點為70℃以上之潤滑油基油,則有極壓劑之效果變得更良好之傾向。 本實施形態之冷凍機油通常於冷凍機中,以與冷媒混合之冷凍機用作動流體組成物之狀態下存在。即,本實施形態之冷凍機用作動流體組成物含有上述之冷凍機油與冷媒。冷凍機用作動流體組成物中之冷凍機油之含量亦可相對於冷媒100質量份,為1~500質量份,或為2~400質量份。 作為冷媒,可列舉:烴冷媒、飽和氟化烴冷媒、不飽和氟化烴冷媒、全氟醚類等含氟醚系冷媒、雙(三氟甲基)硫醚冷媒、三氟化碘化甲烷冷媒、及氨、二氧化碳等自然系冷媒。 烴冷媒較佳為碳數1~5之烴,更佳為碳數2~4之烴。作為烴,具體而言,例如可列舉:甲烷、乙烯、乙烷、丙烯、丙烷(R290)、環丙烷、正丁烷、異丁烷(R600a)、環丁烷、甲基環丙烷、2-甲基丁烷、正戊烷或該等兩種以上之混合物。該等之中,烴冷媒較佳為25℃、1氣壓下氣體之烴冷媒,更佳為丙烷、正丁烷、異丁烷、2-甲基丁烷或該等之混合物。 飽和氟化烴冷媒較佳為碳數1~3,更佳為1~2之飽和氟化烴。作為飽和氟化烴冷媒,具體而言,可列舉:二氟甲烷(R32)、三氟甲烷(R23)、五氟乙烷(R125)、1,1,2,2-四氟乙烷(R134)、1,1,1,2-四氟乙烷(R134a)、1,1,1-三氟乙烷(R143a)、1,1-二氟乙烷(R152a)、氟乙烷(R161)、1,1,1,2,3,3,3-七氟丙烷(R227ea)、1,1,1,2,3,3-六氟丙烷(R236ea)、1,1,1,3,3,3-六氟丙烷(R236fa)、1,1,1,3,3-五氟丙烷(R245fa)、及1,1,1,3,3-五氟丁烷(R365mfc)、或該等兩種以上之混合物。 飽和氟化烴冷媒可自上述之中根據用途或要求性能而適宜選擇。飽和氟化烴冷媒例如R32單獨;R23單獨;R134a單獨;R125單獨;R134a/R32=60~80質量%/40~20質量%之混合物;R32/R125=40~70質量%/60~30質量%之混合物;R125/R143a=40~60質量%/60~40質量%之混合物;R134a/R32/R125=60質量%/30質量%/10質量%之混合物;R134a/R32/R125=40~70質量%/15~35質量%/5~40質量%之混合物;R125/R134a/R143a=35~55質量%/1~15質量%/40~60質量%之混合物等。飽和氟化烴冷媒進而具體而言,亦可為:R134a/R32=70/30質量%之混合物;R32/R125=60/40質量%之混合物;R32/R125=50/50質量%之混合物(R410A);R32/R125=45/55質量%之混合物(R410B);R125/R143a=50/50質量%之混合物(R507C);R32/R125/R134a=30/10/60質量%之混合物;R32/R125/R134a=23/25/52質量%之混合物(R407C);R32/R125/R134a=25/15/60質量%之混合物(R407E);R125/R134a/R143a=44/4/52質量%之混合物(R404A)等。 不飽和氟化烴(HFO)冷媒較佳為碳數2~3之不飽和氟化烴,更佳為氟丙烯,進而較佳為氟數為3~5之氟丙烯。不飽和氟化烴冷媒較佳為1,2,3,3,3-五氟丙烯(HFO-1225ye)、1,3,3,3-四氟丙烯(HFO-1234ze)、2,3,3,3-四氟丙烯(HFO-1234yf)、1,2,3,3-四氟丙烯(HFO-1234ye)、及3,3,3-三氟丙烯(HFO-1243zf)中之任一種或兩種以上之混合物。不飽和氟化烴冷媒就冷媒物性之觀點而言,較佳為選自HFO-1225ye、HFO-1234ze及HFO-1234yf中之一種或兩種以上。不飽和氟化烴冷媒亦可為氟乙烯,較佳為1,1,2,3-三氟乙烯。 本實施形態之冷凍機油及冷凍機用作動流體組成物可較佳地用於:具有往復移動式或旋轉式之密封型壓縮機之空調、冰箱、開放型或密封型之車載空調、除濕機、熱水器、冷凍庫、冷凍冷藏倉庫、自動販賣機、展示櫃、化學設備等冷凍機、具有離心式之壓縮機之冷凍機等。 本實施形態之冷凍機油可與上述冷媒一併使用,但就冷媒混合時之低溫特性及相溶性之方面而言,尤其較佳為與烴冷媒一併使用。同樣,本實施形態之冷凍機用作動流體組成物尤佳為含有烴冷媒。 [實施例] 以下,基於實施例進而具體地說明本發明,但本發明並不限定於實施例。 製備以下所示之冷凍機油(試驗油1~4)。將市售低黏度冷凍機油(試驗油5)與各冷凍機油之性狀一併示於表2。 (試驗油) 試驗油1:於將表1所示之市售之基油1、2及3混合而成之基油(硫分:未達0.005質量%)中,以冷凍機油總量基準計,添加磷酸三甲酚酯1.7質量%及消泡劑5質量 ppm之冷凍機油。 試驗油2:於將表1所示之市售之基油1、2及3混合而成之基油(硫分:未達0.005質量%)中,以冷凍機油總量基準計,添加磷酸三甲酚酯1.7質量%及消泡劑5質量 ppm之冷凍機油。 試驗油3:於將表1所示之市售之基油1、4及5混合而成之基油(硫分:0.005質量%)中,以冷凍機油總量基準計,添加磷酸三甲酚酯1.7質量%及消泡劑5質量 ppm之冷凍機油。 試驗油4:於表1所示之市售之基油1(硫分:未達0.005質量%)中,以冷凍機油總量基準計,添加磷酸三甲酚酯1.7質量%及消泡劑5質量 ppm之冷凍機油。 試驗油5:市售低黏度冷凍機油 [表1]
(耐磨耗性) 對於各冷凍機油,按照以下所示之順序評價耐磨耗性。將結果示於表2。 依據ASTM D2670“FALEX WEAR TEST”,於冷凍機油之溫度60℃、450 N荷重之下進行5分鐘之慣性運動,於890 N荷重之下運行30分鐘試驗機,測定試驗後之測試日誌(接腳)之磨耗量(mg)。 (不良潤滑扭矩試驗) 針對各冷凍機油,按照以下所示之順序進行不良潤滑扭矩試驗。將結果示於表2。 使用上述FALEX試驗機,將潤滑部位於表2所示之各試驗油浴中浸漬一次後,於脫離油浴之狀態下,測定重複10次於100 rpm、荷重890 N之條件下旋轉30秒、停止1分鐘之操作時之平均扭矩(N-m)。 [表2]
(烴冷媒混合時之低溫析出性) 針對試驗油1及2,基於JIS K2211:2009附屬書A「低溫析出性試驗方法」,使用異丁烷(R600a)作為冷媒,測定將試驗油濃度設為10質量%時之低溫析出溫度。此時之低溫析出溫度為-50℃以下,確認試驗油1及2可用作烴冷媒用冷凍機油。 (烴冷媒混合時之雙層分離溫度) 又,針對試驗油1及2,依據JIS K2211:2009附屬書D「與冷媒之相溶性試驗方法」,使用異丁烷(R600a)作為冷媒,測定將試驗油濃度設為10質量%之雙層分離溫度。此時之雙層分離溫度為-50℃以下,確認試驗油1及2可用作烴冷媒用冷凍機油。Hereinafter, the embodiments of the present invention will be described in detail. The dynamic viscosity of refrigerating machine oil at 100°C is 0.5 mm 2 /s or more and 1.5 mm 2 /s or less. The dynamic viscosity of refrigerating machine oil at 100°C is excellent in terms of the balance of wear resistance and energy saving of the refrigerating machine, preferably 0.6 mm 2 /s or more and 1.4 mm 2 /s or less, more preferably 0.8 mm 2 /s or more and 1.3 mm 2 /s or less, more preferably 1.0 mm 2 /s or more and 1.3 mm 2 /s or less. The dynamic viscosity in the present invention means the dynamic viscosity measured based on JIS K2283:2000. The dynamic viscosity of refrigerating machine oil at 40°C may be, for example, 2.0 mm 2 /s or more, 2.5 mm 2 /s or more, or 2.8 mm 2 /s or more, for example, 4.5 mm 2 /s or less, which is 4.0 mm 2 /s or less, or 3.5 mm 2 /s or less. The aniline point of the refrigerating machine oil is 70°C or higher, and from the viewpoint of further excellent abrasion resistance, it is preferably 73°C or higher, more preferably 76°C or higher, and even more preferably 80°C or higher. In addition, if the aniline point is 70°C or higher, the effect of the extreme pressure agent tends to be improved. The aniline point of the refrigerating machine oil is preferably below 100°C from the viewpoint of compatibility with organic materials such as PET (polyethylene terephthalate) materials and sealing materials used in refrigeration equipment (freezers). It is more preferably 95°C or lower, and still more preferably 90°C or lower. The aniline point in the present invention means the value measured based on JIS K2256:2013. The distillation properties of refrigerating machine oil by gas chromatography distillation are excellent in the balance of low viscosity and lubricity of refrigerating machine oil, and furthermore, from the viewpoint of maintaining high ignition point, it is better to increase the low boiling point side. At the same time, the distillation temperature of the high boiling point side is maintained in an appropriate range. Such refrigerating machine oil preferably has the distillation properties described below. The initial boiling point (IBP) of the refrigerating machine oil may be 200°C or higher, 220°C or higher, or 230°C or higher, for example, 260°C or lower, 250°C or lower, or 240°C or lower. The 5% distillation temperature T 5 of the refrigerating machine oil may be, for example, 205°C or higher, 225°C or higher, or 235°C or higher, for example, 265°C or lower, 255°C or lower, or 245°C or lower. The 10% distillation temperature T 10 of the refrigerating machine oil may be, for example, 210°C or higher, 230°C or higher, or 235°C or higher, for example, 270°C or lower, 260°C or lower, or 250°C or lower. The refrigerating machine oil 50% distillation temperature T 50 or more, for example, may also be 230 ℃, less than 250 ℃, or less than 260 ℃, for example, it may also be less 300 ℃, higher than 280 ℃, or higher than 270 ℃. The 70% distillation temperature T 70 of the refrigerating machine oil is preferably 250° C. or higher, more preferably 260° C. or higher, and still more preferably 270° C. or higher from the viewpoint of lubricity and high flash point. The 70% distillation temperature T 70 of the refrigerating machine oil is preferably less than 330°C, more preferably less than 300°C, more preferably 295°C or less, and particularly preferably 290°C or less from the viewpoint of lowering viscosity. The 90% distillation temperature T 90 of the refrigerating machine oil is preferably 280°C or higher and less than 360°C, more preferably 290°C or higher and 355°C or lower, and may also be 280°C or higher in terms of excellent abrasion resistance. And below 350°C, 290°C or higher and 345°C or lower, 300°C or higher and 340°C or lower, or 300°C or higher and 330°C or lower. The 95% distillation temperature T 95 of refrigerating machine oil is, for example, 290°C or higher, 310°C or higher, or 330°C or higher, for example, 390°C or lower, 385°C or lower, 370°C or lower, 360°C or lower, or Below 350°C. From the viewpoint of lubricity, the distillation end point EP of the refrigerating machine oil is preferably 390°C or higher, more preferably 395°C or higher, and still more preferably 400°C or higher. From the viewpoint of lowering the viscosity of the refrigerating machine oil, the end point EP of the distillation is preferably 440°C or lower, more preferably 430°C or lower, still more preferably 425°C or lower, or 420°C or lower, or 415°C or lower, or Below 410°C. The end point EP of the distillation is preferably 390°C or higher and 440°C or lower, more preferably 390°C or higher and 430°C or lower, still more preferably 390°C or higher and 425°C or lower, particularly preferably 395°C or higher and 425°C or lower. It is 390°C or higher and 420°C or lower, 395°C or higher and 410°C or lower, or 400°C or higher and 415°C or lower. In terms of the balance of low viscosity and lubricity of refrigerating machine oil and the maintenance of high ignition point, it is preferable to increase the distillation temperature on the low boiling point side while increasing the high boiling point side as described above. The distillation temperature is maintained in an appropriate range. In addition to the above, it is more desirable that instead of increasing the distillation range, it is better to maintain a moderately narrow range and not too narrow as follows. The difference between the initial boiling point IBP of the refrigerating machine oil and the 95% distillation temperature T 95 (T 95 -IBP) is preferably 60° C. or higher, more preferably 70° C. or higher, and even more preferably 80° C. or higher. The difference between the initial boiling point IBP of the refrigerating machine oil and the 95% distillation temperature T 95 (T 95- IBP) is preferably below 160°C, more preferably below 150°C, further preferably below 140°C, particularly preferably below 130°C . The difference between the initial boiling point IBP and the 95% distillation temperature T 95 (T 95- IBP) is preferably 60°C or more and 160°C or less, more preferably 60°C or more and 150°C or less, preferably 70°C or more and 150°C Below, it may be 70°C or more and 140°C or less, or 80°C or more and 130°C or less. The difference between the end point EP of the refrigeration oil distillation and the 90% distillation temperature T 90 (EP-T 90 ) From the viewpoint of lubricity, it is preferably 40°C or higher, more preferably 50°C or higher, and even more preferably 55°C or higher It may also be 60°C or higher, preferably 140°C or lower, more preferably 130°C or lower, and still more preferably 120°C or lower. The difference between the end point EP of the refrigerating machine oil distillation and the 90% distillation temperature T 90 (EP-T 90 ) is preferably 40°C or more and 140°C or less, more preferably 50°C or more and 130°C or less, and more preferably 55°C or more In addition, 120°C or less may also be 60°C or more and 120°C or less. The difference between the 95% distillation temperature T 95 and the 90% distillation temperature T 90 of the refrigerating machine oil (T 95 -T 90 ) From the viewpoint of lubricity, it is preferably 3°C or higher, more preferably 10°C or higher, and more preferably It is 20°C or higher, particularly preferably 25°C or higher, and may also be 30°C or higher, preferably 80°C or lower, more preferably 70°C or lower, and still more preferably 60°C or lower. The difference between the 95% distillation temperature T 95 and the 90% distillation temperature T 90 (T 95 -T 90 ) is preferably 3°C or more and 80°C or less, more preferably 10°C or more and 80°C or less, and still more preferably 20°C Above and below 70°C, particularly preferably above 25°C and below 60°C, and may also be above 30°C and below 60°C. In the present invention, the initial boiling point, 5% distillation temperature, 10% distillation temperature, 50% distillation temperature, 70% distillation temperature, 90% distillation temperature, 95% distillation temperature and distillation end point respectively refer to those specified in ASTM D7213-05 The initial boiling point, 5 (volume)% distillation temperature, 10 (volume)% distillation temperature, 50 (volume)% distillation temperature, 70 (volume)% distillation temperature, 90 (volume)% distillation temperature, 95 (volume)% distillation temperature and distillation end point. The refractive index of refrigerating machine oil at 20°C is excellent in terms of the low viscosity of refrigerating machine oil and the balance of lubricity, thereby maintaining the high flash point. For example, it may be 1.440 or higher, 1.445 or higher, or 1.450 or more, for example, it may be 1.470 or less, 1.465 or less, or 1.460 or less. The refractive index in the present invention means the refractive index measured at 20°C in accordance with JIS K0062: 1992. The density of refrigerating machine oil at 15°C is excellent in terms of the low viscosity of refrigerating machine oil and the balance of lubricity, and the point of keeping the ignition point high, it can also be preferably 0.86 g/cm 3 or less, more preferably It is 0.85 g/cm 3 or less, more preferably 0.84 g/cm 3 or less, for example, it may be 0.81 g/cm 3 or more and 0.815 g/cm 3 or more. The density in the present invention means the density measured at 15°C in accordance with JIS K2249:2011. The sulfur content of the refrigerating machine oil is not particularly limited. From the standpoint of excellent stability and compatibility with metal materials, it is preferably 0.001% by mass or more, 0.02% by mass or more, or 0.3% by mass or less. 0.1% by mass or less or 0.05% by mass or less. In this embodiment, when the following extreme pressure agent is added to the refrigerating machine oil, for example, 0.2% by mass or more, the sulfur content of the refrigerating machine oil may be less than 0.05% by mass, less than 0.02% by mass, or less than 0.01% by mass or less than 0.005% by mass. The sulfur content in the present invention means the sulfur content measured by ultraviolet fluorescence method specified in JIS K2541-6:2013. The composition ratio of the refrigerating machine oil or the lubricating base oil contained in it by the ring analysis is excellent in terms of the low viscosity of the refrigerating machine oil and the balance of lubricity, and the point of keeping the ignition point high, it is preferable to be The range shown below. Wherein the lubricating oil contained in the refrigerating machine oil or the base oil of the% C P is preferably 40 or more, more preferably 42 or more, more preferably 44 or more, preferably 60 or less, more preferably 57 or less, and further preferably 54 the following. Wherein the lubricating oil contained in the refrigerating machine oil or the base oil of the% C P is preferably 40 or more and 60 or less, more preferably 42 or more and 57 or less, and further preferably 44 or more and 54 or less. The %CN of the refrigerating machine oil or the lubricating base oil contained therein is preferably 40 or more, more preferably 42 or more, still more preferably 44 or more, preferably 65 or less, more preferably 60 or less, and still more preferably 57 or less, especially 54 or less. The %CN of the refrigerating machine oil or the lubricating base oil contained therein is preferably 40 or more and 65 or less, more preferably 42 or more and 60 or less, still more preferably 44 or more and 57 or less, and particularly preferably 44 or more and 54 the following. Wherein the lubricating oil contained in the refrigerating machine oil or the base oil of the% C P with respect to the ratio of the% C N (% C P /% C N ) is preferably 0.6 or more, more preferably 0.7 or more, and further preferably 0.8 or more, It is preferably 1.4 or less, more preferably 1.3 or less, and still more preferably 1.2 or less. Wherein the lubricating oil contained in the refrigerating machine oil or the base oil relative to the% C P% C N ratio (% C P /% C N ) is preferably 0.6 or more and 1.4 or less, more preferably 0.7 or more and 1.3 or less, Preferably it is 0.8 or more and 1.2 or less. Wherein the lubricating oil contained in the refrigerating machine oil or the% C A of base oil or lubricating the viewpoint of stability, it also is preferably 5 or less, more preferably 3 or less, and further preferably 2 or less, may also be 0 may also be preferably 0.5 or more, and 1 or more. The present invention% C P,% C N and% C A values mean respectively method according to ASTM D3238-95 (2010) by the (the ndM ring analysis) of determined. From the standpoint of safety, the ignition point of refrigerating machine oil is preferably 110°C or higher, more preferably 120°C or higher, and particularly preferably 130°C or higher, in order to make the dynamic viscosity at 40°C 2~4 mm 2 /s The low-viscosity oil of about 155°C or lower is preferable, and 145°C or lower is more preferable. The fire point in the present invention means the fire point measured in accordance with JIS K2265-4: 2007 (Kirsch Open Cup (COC) method). The pour point of the refrigerating machine oil may be, for example, -10°C or lower, or -20°C or lower, or may be -50°C or lower, but from the viewpoint of refining cost, it may be -40°C or higher. The flow point in the present invention means the flow point measured in accordance with JIS K2269:1987. The acid value of the refrigerating machine oil may be 1.0 mgKOH/g or less, or 0.1 mgKOH/g or less, for example. The acid value in the present invention means the acid value measured in accordance with JIS K2501:2003. The volume resistivity of the refrigerating machine oil may be 1.0×10 9 Ω·m or more, 1.0×10 10 Ω·m or more, or 1.0×10 11 Ω·m or more, for example. The volume resistivity in the present invention means the volume resistivity at 25°C measured in accordance with JIS C2101:1999. The moisture content of refrigerating machine oil is calculated based on the total amount of refrigerating machine oil, for example, it can be 200 ppm or less, 100 ppm or less, or 50 ppm or less. The ash content of the refrigerating machine oil may be 100 ppm or less, or 50 ppm or less, for example. The ash content in the present invention means the ash content measured in accordance with JIS K2272:1998. The refrigerating machine oil is a refrigerating machine oil with the following properties: In one embodiment, among the above properties, the dynamic viscosity at least at 100°C is 0.5 mm 2 /s or more and 1.5 mm 2 /s or less by gas chromatography The 90% distillation temperature of the distillation is above 280℃ and below 360℃, and the aniline point is above 70℃. The refrigerating machine oil is a refrigerating machine oil with the following properties: In another embodiment, among the above properties, at least a dynamic viscosity at 100°C of 0.5 mm 2 /s or more and 1.5 mm 2 /s or less, by gas chromatography The 70% distillation temperature of method distillation is above 270℃ and below 300℃, and the aniline point is above 70℃. The refrigerating machine oil having the above-mentioned properties contains, for example, a lubricating oil base oil and a lubricating oil additive. As the lubricating base oil, for example, mineral oil can be mentioned. Mineral oil can be desolventized, solvent refined, hydrorefined, hydrocracked, solvent dewaxed, solvent dewaxed, and lubricating oil obtained by atmospheric distillation and vacuum distillation of crude oils such as paraffin and naphthenic oils. Hydrogen dewaxing, clay treatment, sulfuric acid washing and other methods are refined and obtained. These refining methods can be used alone or in combination of two or more. As the lubricating base oil, from the viewpoint of availability, it is preferable to use a lubricating base oil of low viscosity, which is generally used for solvents, diluents, metal working oils, and the like. In order to produce a refrigerating machine oil having the above-mentioned properties, the properties of the lubricating base oil as the main component (for example, 90% by mass or more) are preferably the same as the above-mentioned properties as long as they are not specifically defined in this specification. Therefore, although the properties of each item of refrigerating machine oil in the above show a better range, as long as it is not specified in this manual, it can be renamed as the item of the lubricating base oil contained in refrigerating machine oil. The preferred range. The sulfur content of the lubricating base oil is not particularly limited, but from the standpoint of excellent stability and compatibility with metal materials, it is preferably 0.001% by mass or more, 0.02% by mass or more, or 0.3% by mass or less, It may be 0.1% by mass or less or 0.05% by mass or less. In this embodiment, when the following extreme pressure agent is added to the refrigerating machine oil, such as 0.2% by mass or more, the sulfur content of the lubricating oil base oil can also be less than 0.05% by mass, or less than 0.02% by mass, which is not It is 0.01% by mass or less than 0.005% by mass. The lubricating oil base oil may also contain the above-mentioned mineral oil. Generally, based on the total amount of the lubricating base oil, the ratio of the mineral oil may also be 50% by mass or more, preferably 70% by mass or more, and particularly preferably 90% by mass or more, As long as the effect of the present invention is not significantly hindered, in addition to the above-mentioned mineral oil, hydrocarbon oils such as alkylbenzene, or oxygenated oils such as esters may be further contained. The alkylbenzene may be at least one selected from the group consisting of the following alkylbenzene (a1) and alkylbenzene (a2). Alkylbenzene (a1): alkylbenzene having 1 to 4 alkyl groups having 1 to 19 carbon atoms and having a total carbon number of 9 to 19 (preferably having 1 to 4 carbon numbers 1 to 19). The alkyl group of 15 and the total carbon number of the alkyl group is 9-15 alkylbenzene) Alkylbenzene (a2): an alkyl group having 1 to 4 carbon atoms and 1-40 carbon number, and the total carbon number of the alkyl group 20-40 alkyl benzene (preferably having 1 to 4 alkyl benzenes with 1-30 carbons, and the total number of carbons in the alkyl group is 20-30 alkyl benzenes). The ester may be, for example, a monohydric alcohol or Ester of glycol and fatty acid. The monohydric alcohol or the dihydric alcohol may be an aliphatic alcohol having 4 to 12 carbon atoms, for example. The fatty acid may be a fatty acid having 4 to 18 carbon atoms, for example. The dynamic viscosity of the lubricating base oil at 40°C can be, for example, 2.0 mm 2 /s or more, 2.5 mm 2 /s or more, or 2.8 mm 2 /s or more, for example, it can also be 4.5 mm 2 /s or less. It is 4.0 mm 2 /s or less, or 3.5 mm 2 /s or less. The dynamic viscosity of the lubricating base oil at 100°C may be 0.5 mm 2 /s or more, 0.6 mm 2 /s or more, 0.8 mm 2 /s or more, or 1.0 mm 2 /s or more, for example. 1.5 mm 2 /s or less, 1.4 mm 2 /s or less, or 1.3 mm 2 /s or less. The content of the lubricating base oil is based on the total amount of refrigerating machine oil, and it can also be 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. Above mass%. Examples of lubricant additives include: acid scavengers, antioxidants, extreme pressure agents, oily agents, defoamers, metal deactivators, anti-wear agents, viscosity index improvers, pour point depressants, and purification dispersants Wait. The content of these additives is calculated based on the total amount of refrigerating machine oil, and may also be 10% by mass or less or 5% by mass or less. The refrigerating machine oil preferably contains an extreme pressure agent from the viewpoint that among the above-mentioned additives, abrasion resistance is also excellent. As a preferable extreme pressure agent, a phosphorus-based extreme pressure agent can be cited. Examples of the phosphorus-based extreme pressure agent include phosphoric acid esters, acidic phosphoric acid esters, amine salts of acidic phosphoric acid esters, chlorinated phosphoric acid esters, phosphorous acid esters, and phosphorothioate esters. The phosphate is preferably triphenyl phosphate (TPP) or tricresyl phosphate (TCP). The content of the phosphorus extreme pressure agent is based on the total amount of refrigerating machine oil. For example, it may be 0.2% by mass or more, preferably 0.5-5% by mass, more preferably 1-4% by mass, and particularly preferably 1.5-3% by mass. %. If a lubricating base oil with an aniline point of 70°C or higher is used, the effect of the extreme pressure agent tends to become better. The refrigerating machine oil of this embodiment is usually present in a refrigerating machine in a state where a refrigerating machine mixed with a refrigerant is used as a dynamic fluid composition. That is, the refrigerating machine of this embodiment is used as a moving fluid composition containing the above-mentioned refrigerating machine oil and refrigerant. The content of the refrigerating machine oil used in the moving fluid composition of the refrigerator may be 1 to 500 parts by mass, or 2 to 400 parts by mass relative to 100 parts by mass of the refrigerant. Examples of refrigerants include hydrocarbon refrigerants, saturated fluorinated hydrocarbon refrigerants, unsaturated fluorinated hydrocarbon refrigerants, perfluoroethers and other fluorinated ether-based refrigerants, bis(trifluoromethyl)sulfide refrigerants, and trifluoromethyl iodide Refrigerants, and natural refrigerants such as ammonia and carbon dioxide. The hydrocarbon refrigerant is preferably a hydrocarbon having 1 to 5 carbon atoms, and more preferably a hydrocarbon having 2 to 4 carbon atoms. Specific examples of hydrocarbons include methane, ethylene, ethane, propylene, propane (R290), cyclopropane, n-butane, isobutane (R600a), cyclobutane, methylcyclopropane, 2- Methyl butane, n-pentane or a mixture of two or more of these. Among them, the hydrocarbon refrigerant is preferably a gaseous hydrocarbon refrigerant at 25° C. and 1 atmosphere, and more preferably propane, n-butane, isobutane, 2-methylbutane or a mixture of these. The saturated fluorinated hydrocarbon refrigerant is preferably a saturated fluorinated hydrocarbon having 1 to 3 carbon atoms, more preferably 1 to 2 carbon atoms. As saturated fluorinated hydrocarbon refrigerants, specifically, difluoromethane (R32), trifluoromethane (R23), pentafluoroethane (R125), 1,1,2,2-tetrafluoroethane (R134 ), 1,1,1,2-tetrafluoroethane (R134a), 1,1,1-trifluoroethane (R143a), 1,1-difluoroethane (R152a), fluoroethane (R161) , 1,1,1,2,3,3,3-Heptafluoropropane (R227ea), 1,1,1,2,3,3-Hexafluoropropane (R236ea), 1,1,1,3,3,3 -Hexafluoropropane (R236fa), 1,1,1,3,3-pentafluoropropane (R245fa), and 1,1,1,3,3-pentafluorobutane (R365mfc), or two or more of these The mixture. The saturated fluorinated hydrocarbon refrigerant can be appropriately selected from the above according to the application or required performance. Saturated fluorinated hydrocarbon refrigerants such as R32 alone; R23 alone; R134a alone; R125 alone; R134a/R32=60~80% by mass/40~20% by mass; R32/R125=40~70% by mass/60~30 by mass % Mixture; R125/R143a=40-60% by mass/60-40% by mass; R134a/R32/R125=60% by mass/30% by mass/10% by mass; R134a/R32/R125=40~ 70% by mass/15-35% by mass/5-40% by mass; R125/R134a/R143a=35-55% by mass/1-15% by mass/40-60% by mass, etc. More specifically, the saturated fluorinated hydrocarbon refrigerant may also be: R134a/R32=70/30 mass% mixture; R32/R125=60/40 mass% mixture; R32/R125=50/50 mass% mixture ( R410A); R32/R125=45/55 mass% mixture (R410B); R125/R143a=50/50 mass% mixture (R507C); R32/R125/R134a=30/10/60 mass% mixture; R32 /R125/R134a=23/25/52 mass% mixture (R407C); R32/R125/R134a=25/15/60 mass% mixture (R407E); R125/R134a/R143a=44/4/52 mass% The mixture (R404A) and so on. The unsaturated fluorinated hydrocarbon (HFO) refrigerant is preferably an unsaturated fluorinated hydrocarbon having a carbon number of 2 to 3, more preferably a fluoropropylene, and still more preferably a fluoropropylene having a fluorine number of 3 to 5. The unsaturated fluorinated hydrocarbon refrigerant is preferably 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 1,3,3,3-tetrafluoropropene (HFO-1234ze), 2,3,3 , 3-tetrafluoropropene (HFO-1234yf), 1,2,3,3-tetrafluoropropene (HFO-1234ye), and 3,3,3-trifluoropropene (HFO-1243zf) any one or both A mixture of more than species. The unsaturated fluorinated hydrocarbon refrigerant is preferably one or two or more selected from HFO-1225ye, HFO-1234ze, and HFO-1234yf from the viewpoint of refrigerant physical properties. The unsaturated fluorinated hydrocarbon refrigerant may also be fluoroethylene, preferably 1,1,2,3-trifluoroethylene. The refrigerating machine oil and the refrigerating machine of this embodiment can be preferably used as a dynamic fluid composition for: air conditioners with reciprocating or rotary sealed compressors, refrigerators, open or sealed vehicle air conditioners, dehumidifiers, Refrigerators such as water heaters, freezers, refrigerated warehouses, vending machines, display cabinets, chemical equipment, and freezers with centrifugal compressors, etc. The refrigerating machine oil of this embodiment can be used together with the above-mentioned refrigerant, but in terms of low-temperature characteristics and compatibility when the refrigerant is mixed, it is particularly preferable to use it together with a hydrocarbon refrigerant. Similarly, the refrigerator of this embodiment preferably contains a hydrocarbon refrigerant as the dynamic fluid composition. [Examples] Hereinafter, the present invention will be explained more specifically based on examples, but the present invention is not limited to the examples. Prepare the following refrigerating machine oils (test oils 1 to 4). The properties of the commercially available low-viscosity refrigerating machine oil (test oil 5) and each refrigerating machine oil are shown in Table 2. (Test oil) Test oil 1: In the base oil (sulfur content: less than 0.005% by mass) of the commercially available base oils 1, 2 and 3 shown in Table 1, calculated on the basis of the total amount of refrigerating machine oil , Add refrigerating machine oil with 1.7% by mass of tricresol phosphate and 5 ppm by mass of defoamer. Test oil 2: In the base oil (sulfur content: less than 0.005% by mass) of the commercially available base oils 1, 2 and 3 shown in Table 1, added trimethyl phosphate based on the total amount of refrigerating machine oil Refrigeration oil with 1.7% by mass of phenolic ester and 5 ppm by mass of defoamer. Test oil 3: In the base oil (sulfur content: 0.005 mass%) obtained by mixing the commercially available base oils 1, 4, and 5 shown in Table 1, based on the total amount of refrigerating machine oil, tricresol phosphate was added 1.7 mass% and 5 mass ppm of defoamer refrigerating machine oil. Test oil 4: In the commercially available base oil 1 (sulfur content: less than 0.005 mass%) shown in Table 1, based on the total amount of refrigerating machine oil, 1.7% by mass of tricresol phosphate and 5 mass% of defoamer were added ppm of refrigeration oil. Test oil 5: Commercially available low-viscosity refrigerator oil [Table 1] (Abrasion resistance) For each refrigerating machine oil, the abrasion resistance was evaluated in the order shown below. The results are shown in Table 2. According to ASTM D2670 "FALEX WEAR TEST", inertial movement is carried out for 5 minutes under a load of 450 N at the temperature of refrigerating oil at 60°C, and the test machine is run under a load of 890 N for 30 minutes to determine the test log after the test (pin ) The amount of wear (mg). (Bad lubrication torque test) For each refrigerating machine oil, perform a bad lubrication torque test in the order shown below. The results are shown in Table 2. Using the FALEX testing machine described above, the lubrication part was immersed once in each test oil bath shown in Table 2, and the measurement was repeated 10 times under the condition of 100 rpm and a load of 890 N, rotating for 30 seconds, while leaving the oil bath. The average torque (N-m) when the operation is stopped for 1 minute. [Table 2] (Low-temperature precipitation when hydrocarbon refrigerant is mixed) For test oils 1 and 2, based on JIS K2211:2009 Appendix A "Test Method for Low-temperature Separability", isobutane (R600a) is used as the refrigerant, and the concentration of the test oil is measured as Low temperature precipitation temperature at 10% by mass. At this time, the low-temperature precipitation temperature is below -50°C, confirming that the test oils 1 and 2 can be used as refrigerating machine oils for hydrocarbon refrigerants. (Double-layer separation temperature when hydrocarbon refrigerant is mixed) In addition, for test oils 1 and 2, in accordance with JIS K2211:2009 Appendix D "Test Method for Compatibility with Refrigerants", isobutane (R600a) is used as the refrigerant, and the measurement The test oil concentration was set to a double-layer separation temperature of 10% by mass. At this time, the double-layer separation temperature is below -50°C, confirming that the test oils 1 and 2 can be used as refrigerating machine oils for hydrocarbon refrigerants.