diff --git a/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs b/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs
new file mode 100644
index 000000000..6de7f163b
--- /dev/null
+++ b/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs
@@ -0,0 +1,73 @@
+using System;
+using UnityEngine;
+
+namespace UniGLTF
+{
+    public enum ColorSpace
+    {
+        sRGB,
+        Linear,
+    }
+    
+    public static class ColorConversionExtensions
+    {
+        public static float[] ToFloat4(this Color src, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
+        {
+            var dst = src.ConvertColorSpace(srcColorSpace, dstColorSpace);
+            return new float[] {dst.r, dst.g, dst.b, dst.a};
+        }
+        
+        public static float[] ToFloat3(this Color src, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
+        {
+            var dst = src.ConvertColorSpace(srcColorSpace, dstColorSpace);
+            return new float[] {dst.r, dst.g, dst.b};
+        }
+        
+        public static Color ToColor4(this float[] src, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
+        {
+            if (src == null || src.Length < 4)
+            {
+                Debug.LogWarning("Invalid argument.");
+                return Color.magenta;
+            }
+
+            return new Color(src[0], src[1], src[2], src[3]).ConvertColorSpace(srcColorSpace, dstColorSpace);
+        }
+        
+        public static Color ToColor3(this float[] src, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
+        {
+            if (src == null || src.Length < 3)
+            {
+                Debug.LogWarning("Invalid argument.");
+                return Color.magenta;
+            }
+
+            return new Color(src[0], src[1], src[2], 1f).ConvertColorSpace(srcColorSpace, dstColorSpace);
+        }
+
+        private static Color ConvertColorSpace(this Color srcColor, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
+        {
+            // Need pattern matching :(
+            if (srcColorSpace == ColorSpace.sRGB && dstColorSpace == ColorSpace.sRGB)
+            {
+                return srcColor;
+            }
+            else if (srcColorSpace == ColorSpace.sRGB && dstColorSpace == ColorSpace.Linear)
+            {
+                return srcColor.linear;
+            }
+            else if (srcColorSpace == ColorSpace.Linear && dstColorSpace == ColorSpace.sRGB)
+            {
+                return srcColor.gamma;
+            }
+            else if (srcColorSpace == ColorSpace.Linear && dstColorSpace == ColorSpace.Linear)
+            {
+                return srcColor;
+            }
+            else
+            {
+                throw new ArgumentException();
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs.meta b/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs.meta
new file mode 100644
index 000000000..7c0672cd9
--- /dev/null
+++ b/Assets/UniGLTF/Runtime/Extensions/ColorConversionExtensions.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: c2b6bc13ed6e459e98834507edfede07
+timeCreated: 1620378376
\ No newline at end of file
diff --git a/Assets/UniGLTF/Runtime/Extensions/UnityExtensions.cs b/Assets/UniGLTF/Runtime/Extensions/UnityExtensions.cs
index 37018488f..f51247633 100644
--- a/Assets/UniGLTF/Runtime/Extensions/UnityExtensions.cs
+++ b/Assets/UniGLTF/Runtime/Extensions/UnityExtensions.cs
@@ -281,11 +281,6 @@ namespace UniGLTF
             return new float[] { v.x, v.y, v.z, v.w };
         }
 
-        public static float[] ToArray(this Color c)
-        {
-            return new float[] { c.r, c.g, c.b, c.a };
-        }
-
         public static void ReverseRecursive(this Transform root, IAxisInverter axisInverter)
         {
             var globalMap = root.Traverse().ToDictionary(x => x, x => PosRot.FromGlobalTransform(x));
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfPBRMaterial.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfPBRMaterial.cs
index 434a8b826..b38096100 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfPBRMaterial.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfPBRMaterial.cs
@@ -1,8 +1,6 @@
-using System.Threading.Tasks;
-using UnityEngine;
+using UnityEngine;
 using VRMShaders;
 
-
 namespace UniGLTF
 {
     /// <summary>
@@ -103,8 +101,9 @@ namespace UniGLTF
 
                 if (src.pbrMetallicRoughness.baseColorFactor != null && src.pbrMetallicRoughness.baseColorFactor.Length == 4)
                 {
-                    var color = src.pbrMetallicRoughness.baseColorFactor;
-                    param.Colors.Add("_Color", (new Color(color[0], color[1], color[2], color[3])).gamma);
+                    param.Colors.Add("_Color",
+                        src.pbrMetallicRoughness.baseColorFactor.ToColor4(ColorSpace.Linear, ColorSpace.sRGB)
+                    );
                 }
 
                 if (src.pbrMetallicRoughness.baseColorTexture != null && src.pbrMetallicRoughness.baseColorTexture.index != -1)
@@ -153,7 +152,9 @@ namespace UniGLTF
 
                 if (src.emissiveFactor != null && src.emissiveFactor.Length == 3)
                 {
-                    param.Colors.Add("_EmissionColor", new Color(src.emissiveFactor[0], src.emissiveFactor[1], src.emissiveFactor[2]));
+                    param.Colors.Add("_EmissionColor",
+                        src.emissiveFactor.ToColor3(ColorSpace.Linear, ColorSpace.Linear)
+                    );
                 }
 
                 if (src.emissiveTexture != null && src.emissiveTexture.index != -1)
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfUnlitMaterial.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfUnlitMaterial.cs
index 06a6b842f..18283cf2b 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfUnlitMaterial.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/GltfUnlitMaterial.cs
@@ -36,8 +36,9 @@ namespace UniGLTF
             // color
             if (src.pbrMetallicRoughness.baseColorFactor != null && src.pbrMetallicRoughness.baseColorFactor.Length == 4)
             {
-                var color = src.pbrMetallicRoughness.baseColorFactor;
-                param.Colors.Add("_Color", (new Color(color[0], color[1], color[2], color[3])).gamma);
+                param.Colors.Add("_Color",
+                    src.pbrMetallicRoughness.baseColorFactor.ToColor4(ColorSpace.Linear, ColorSpace.sRGB)
+                );
             }
 
             //renderMode
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/MaterialExporter.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/MaterialExporter.cs
index b0fc0a210..461c011ee 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/MaterialExporter.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/MaterialExporter.cs
@@ -38,7 +38,7 @@ namespace UniGLTF
         {
             if (m.HasProperty("_Color"))
             {
-                material.pbrMetallicRoughness.baseColorFactor = m.color.linear.ToArray();
+                material.pbrMetallicRoughness.baseColorFactor = m.GetColor("_Color").ToFloat4(ColorSpace.sRGB, ColorSpace.Linear);
             }
 
             if (m.HasProperty("_MainTex"))
@@ -161,7 +161,7 @@ namespace UniGLTF
                 {
                     color /= color.maxColorComponent;
                 }
-                material.emissiveFactor = new float[] { color.r, color.g, color.b };
+                material.emissiveFactor = color.ToFloat3(ColorSpace.Linear, ColorSpace.Linear);
             }
 
             if (m.HasProperty("_EmissionMap"))
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs
deleted file mode 100644
index 1274075ee..000000000
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs
+++ /dev/null
@@ -1,52 +0,0 @@
-using System;
-using System.Linq;
-using UnityEngine;
-
-namespace UniGLTF
-{
-    public static class ColorSpace
-    {
-        public static RenderTextureReadWrite GetColorSpace(this glTFTextureTypes textureType)
-        {
-            switch (textureType)
-            {
-                case glTFTextureTypes.SRGB:
-                    return RenderTextureReadWrite.sRGB;
-                case glTFTextureTypes.OcclusionMetallicRoughness:
-                case glTFTextureTypes.Normal:
-                    return RenderTextureReadWrite.Linear;
-                default:
-                    throw new NotImplementedException();
-            }
-        }
-
-        public static bool TryGetglTFTextureType(this glTF glTf, int textureIndex, out glTFTextureTypes textureType)
-        {
-            foreach (var material in glTf.materials)
-            {
-                var textureInfo = material.GetTextures().FirstOrDefault(x => (x != null) && x.index == textureIndex);
-                if (textureInfo != null)
-                {
-                    textureType = textureInfo.TextureType;
-                    return true;
-                }
-            }
-
-            // textureIndex is not used by Material.
-            textureType = default;
-            return false;
-        }
-
-        public static RenderTextureReadWrite GetColorSpace(this glTF gltf, int textureIndex)
-        {
-            if (TryGetglTFTextureType(gltf, textureIndex, out glTFTextureTypes textureType))
-            {
-                return GetColorSpace(textureType);
-            }
-            else
-            {
-                return RenderTextureReadWrite.sRGB;
-            }
-        }
-    }
-}
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs.meta b/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs.meta
deleted file mode 100644
index d5bf0544c..000000000
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/TextureIO/ColorSpace.cs.meta
+++ /dev/null
@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: 1a3edb24329fd454db97cac12f30c0d8
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 
diff --git a/Assets/VRM/Runtime/IO/VRMMaterialExporter.cs b/Assets/VRM/Runtime/IO/VRMMaterialExporter.cs
index e484d256a..7b65783d2 100644
--- a/Assets/VRM/Runtime/IO/VRMMaterialExporter.cs
+++ b/Assets/VRM/Runtime/IO/VRMMaterialExporter.cs
@@ -5,6 +5,7 @@ using UniGLTF;
 using UniGLTF.ShaderPropExporter;
 using UnityEngine;
 using VRMShaders;
+using ColorSpace = UniGLTF.ColorSpace;
 
 namespace VRM
 {
@@ -160,7 +161,8 @@ namespace VRM
                     {
                         case ShaderPropertyType.Color:
                             {
-                                var value = m.GetColor(kv.Key).ToArray();
+                                // No color conversion. Because color property is serialized to raw float array.
+                                var value = m.GetColor(kv.Key).ToFloat4(ColorSpace.Linear, ColorSpace.Linear);
                                 material.vectorProperties.Add(kv.Key, value);
                             }
                             break;
diff --git a/Assets/VRM10/Runtime/IO/Vrm10MaterialExporter.cs b/Assets/VRM10/Runtime/IO/Vrm10MaterialExporter.cs
index 234053eef..edd5ee869 100644
--- a/Assets/VRM10/Runtime/IO/Vrm10MaterialExporter.cs
+++ b/Assets/VRM10/Runtime/IO/Vrm10MaterialExporter.cs
@@ -1,6 +1,7 @@
 using UniGLTF;
 using UnityEngine;
 using VRMShaders;
+using ColorSpace = UniGLTF.ColorSpace;
 
 namespace UniVRM10
 {
@@ -23,14 +24,14 @@ namespace UniVRM10
 
                 pbrMetallicRoughness = new glTFPbrMetallicRoughness
                 {
-                    baseColorFactor = def.Color.LitColor.ToArray(),
+                    baseColorFactor = def.Color.LitColor.ToFloat4(ColorSpace.sRGB, ColorSpace.Linear),
                     baseColorTexture = new glTFMaterialBaseColorTextureInfo
                     {
                         index = textureExporter.ExportSRGB(def.Color.LitMultiplyTexture),
                     },
                 },
 
-                emissiveFactor = def.Emission.EmissionColor.ToArray(),
+                emissiveFactor = def.Emission.EmissionColor.ToFloat3(ColorSpace.Linear, ColorSpace.Linear),
             };
 
             // VRMC_materials_mtoon
diff --git a/Assets/VRM10/Runtime/IO/Vrm10MaterialImporter.cs b/Assets/VRM10/Runtime/IO/Vrm10MaterialImporter.cs
index 5ca26aa08..3f42855c1 100644
--- a/Assets/VRM10/Runtime/IO/Vrm10MaterialImporter.cs
+++ b/Assets/VRM10/Runtime/IO/Vrm10MaterialImporter.cs
@@ -1,45 +1,11 @@
-using System;
-using System.Collections.Generic;
-using System.Threading.Tasks;
-using UniGLTF;
+using UniGLTF;
 using UnityEngine;
 using VRMShaders;
 
-
 namespace UniVRM10
 {
     public static class Vrm10MaterialImporter
     {
-        public static Color ToColor4(this float[] src, Color defaultValue = default)
-        {
-            if (src == null || src.Length != 4)
-            {
-                throw new NotImplementedException();
-            }
-
-            var v = new Vector4(
-                src[0],
-                src[1],
-                src[2],
-                src[3]
-            );
-            return v;
-        }
-        public static Color ToColor3(this float[] src, Color defaultValue = default)
-        {
-            if (src == null || src.Length < 3)
-            {
-                throw new NotImplementedException();
-            }
-
-            var v = new Vector4(
-                src[0],
-                src[1],
-                src[2]
-            );
-            return v;
-        }
-
         /// <summary>
         /// VMRC_materials_mtoon の場合にマテリアル生成情報を作成する
         /// </summary>
@@ -75,8 +41,15 @@ namespace UniVRM10
                 }
                 {
                     // var color = mtoon.Color;
-                    material.SetColor(MToon.Utils.PropColor, m.pbrMetallicRoughness.baseColorFactor.ToColor4());
-                    if (mtoon.ShadeColorFactor != null) material.SetColor(MToon.Utils.PropShadeColor, mtoon.ShadeColorFactor.ToColor3());
+                    material.SetColor(MToon.Utils.PropColor, m.pbrMetallicRoughness.baseColorFactor
+                        .ToColor4(UniGLTF.ColorSpace.Linear, UniGLTF.ColorSpace.sRGB)
+                    );
+                    if (mtoon.ShadeColorFactor != null)
+                    {
+                        material.SetColor(MToon.Utils.PropShadeColor, mtoon.ShadeColorFactor
+                            .ToColor3(UniGLTF.ColorSpace.Linear, UniGLTF.ColorSpace.sRGB)
+                        );
+                    }
                     material.SetFloat(MToon.Utils.PropCutoff, m.alphaCutoff);
                 }
                 {
@@ -91,17 +64,29 @@ namespace UniVRM10
                     }
                 }
                 {
-                    material.SetColor(MToon.Utils.PropEmissionColor, m.emissiveFactor.ToColor3());
+                    material.SetColor(MToon.Utils.PropEmissionColor,
+                        m.emissiveFactor.ToColor3(UniGLTF.ColorSpace.Linear, UniGLTF.ColorSpace.Linear)
+                    );
                 }
                 {
-                    if (mtoon.ParametricRimColorFactor != null) material.SetColor(MToon.Utils.PropRimColor, mtoon.ParametricRimColorFactor.ToColor3());
+                    if (mtoon.ParametricRimColorFactor != null)
+                    {
+                        material.SetColor(MToon.Utils.PropRimColor, mtoon.ParametricRimColorFactor
+                            .ToColor3(UniGLTF.ColorSpace.Linear, UniGLTF.ColorSpace.sRGB)
+                        );
+                    }
                     if (mtoon.RimLightingMixFactor.HasValue) material.SetFloat(MToon.Utils.PropRimLightingMix, mtoon.RimLightingMixFactor.Value);
                     if (mtoon.ParametricRimFresnelPowerFactor.HasValue) material.SetFloat(MToon.Utils.PropRimFresnelPower, mtoon.ParametricRimFresnelPowerFactor.Value);
                     if (mtoon.ParametricRimLiftFactor.HasValue) material.SetFloat(MToon.Utils.PropRimLift, mtoon.ParametricRimLiftFactor.Value);
                 }
                 {
                     if (mtoon.OutlineWidthFactor.HasValue) material.SetFloat(MToon.Utils.PropOutlineWidth, mtoon.OutlineWidthFactor.Value);
-                    if (mtoon.OutlineColorFactor != null) material.SetColor(MToon.Utils.PropOutlineColor, mtoon.OutlineColorFactor.ToColor3());
+                    if (mtoon.OutlineColorFactor != null)
+                    {
+                        material.SetColor(MToon.Utils.PropOutlineColor, mtoon.OutlineColorFactor
+                            .ToColor3(UniGLTF.ColorSpace.Linear, UniGLTF.ColorSpace.sRGB)
+                        );
+                    }
                     if (mtoon.OutlineLightingMixFactor.HasValue) material.SetFloat(MToon.Utils.PropOutlineLightingMix, mtoon.OutlineLightingMixFactor.Value);
 
                     // private
diff --git a/Assets/VRM10/Runtime/Migration/MigrationMToon.cs b/Assets/VRM10/Runtime/Migration/MigrationMToon.cs
index f74402795..1a07cf141 100644
--- a/Assets/VRM10/Runtime/Migration/MigrationMToon.cs
+++ b/Assets/VRM10/Runtime/Migration/MigrationMToon.cs
@@ -5,25 +5,15 @@ using UniGLTF;
 using UniGLTF.Extensions.VRMC_materials_mtoon;
 using UniJSON;
 using UnityEngine;
-
+using ColorSpace = UniGLTF.ColorSpace;
 
 namespace UniVRM10
 {
     public static class MigrationMToon
     {
-        static float[] ToFloat4(this Color color)
+        static Color ToColor(JsonNode node, ColorSpace srcColorSpace, ColorSpace dstColorSpace)
         {
-            return new float[] { color.r, color.g, color.b, color.a };
-        }
-
-        static float[] ToFloat3(this Color color)
-        {
-            return new float[] { color.r, color.g, color.b };
-        }
-
-        static Color ToColor(JsonNode node)
-        {
-            return node.ArrayItems().Select(x => x.GetSingle()).ToArray().ToColor4();
+            return node.ArrayItems().Select(x => x.GetSingle()).ToArray().ToColor4(srcColorSpace, dstColorSpace);
         }
 
         static float[] ToFloat4(JsonNode node)
@@ -90,23 +80,23 @@ namespace UniVRM10
                     switch (key)
                     {
                         case "_Color":
-                            definition.Color.LitColor = ToColor(kv.Value);
+                            definition.Color.LitColor = ToColor(kv.Value, ColorSpace.sRGB, ColorSpace.sRGB);
                             break;
 
                         case "_ShadeColor":
-                            definition.Color.ShadeColor = ToColor(kv.Value);
+                            definition.Color.ShadeColor = ToColor(kv.Value, ColorSpace.sRGB, ColorSpace.sRGB);
                             break;
 
                         case "_EmissionColor":
-                            definition.Emission.EmissionColor = ToColor(kv.Value);
+                            definition.Emission.EmissionColor = ToColor(kv.Value, ColorSpace.Linear, ColorSpace.Linear);
                             break;
 
                         case "_OutlineColor":
-                            definition.Outline.OutlineColor = ToColor(kv.Value);
+                            definition.Outline.OutlineColor = ToColor(kv.Value, ColorSpace.sRGB, ColorSpace.sRGB);
                             break;
 
                         case "_RimColor":
-                            definition.Rim.RimColor = ToColor(kv.Value);
+                            definition.Rim.RimColor = ToColor(kv.Value, ColorSpace.sRGB, ColorSpace.sRGB);
                             break;
 
                         case "_MainTex":
@@ -315,7 +305,7 @@ namespace UniVRM10
                 var dst = new VRMC_materials_mtoon();
 
                 // Color
-                gltfMaterial.pbrMetallicRoughness.baseColorFactor = mtoon.Definition.Color.LitColor.ToFloat4();
+                gltfMaterial.pbrMetallicRoughness.baseColorFactor = mtoon.Definition.Color.LitColor.ToFloat4(ColorSpace.sRGB, ColorSpace.Linear);
                 if (mtoon.TextureIndexMap.MainTex.HasValue)
                 {
                     gltfMaterial.pbrMetallicRoughness.baseColorTexture = new glTFMaterialBaseColorTextureInfo
@@ -332,7 +322,7 @@ namespace UniVRM10
                         (value[2], value[3])
                         );
                 }
-                dst.ShadeColorFactor = mtoon.Definition.Color.ShadeColor.ToFloat3();
+                dst.ShadeColorFactor = mtoon.Definition.Color.ShadeColor.ToFloat3(ColorSpace.sRGB, ColorSpace.Linear);
                 if (mtoon.TextureIndexMap.ShadeTexture.HasValue)
                 {
                     dst.ShadeMultiplyTexture = new TextureInfo { Index = mtoon.TextureIndexMap.ShadeTexture.Value };
@@ -340,7 +330,7 @@ namespace UniVRM10
                 gltfMaterial.alphaCutoff = mtoon.Definition.Color.CutoutThresholdValue;
 
                 // Outline
-                dst.OutlineColorFactor = ToFloat3(mtoon.Definition.Outline.OutlineColor);
+                dst.OutlineColorFactor = mtoon.Definition.Outline.OutlineColor.ToFloat3(ColorSpace.sRGB, ColorSpace.Linear);
                 dst.OutlineLightingMixFactor = mtoon.Definition.Outline.OutlineLightingMixValue;
                 dst.OutlineWidthMode = (UniGLTF.Extensions.VRMC_materials_mtoon.OutlineWidthMode)mtoon.Definition.Outline.OutlineWidthMode;
                 dst.OutlineWidthFactor = mtoon.Definition.Outline.OutlineWidthValue;
@@ -350,7 +340,7 @@ namespace UniVRM10
                 }
 
                 // Emission
-                gltfMaterial.emissiveFactor = mtoon.Definition.Emission.EmissionColor.ToFloat3();
+                gltfMaterial.emissiveFactor = mtoon.Definition.Emission.EmissionColor.ToFloat3(ColorSpace.Linear, ColorSpace.Linear);
                 if (mtoon.TextureIndexMap.EmissionMap.HasValue)
                 {
                     gltfMaterial.emissiveTexture = new glTFMaterialEmissiveTextureInfo
@@ -413,7 +403,7 @@ namespace UniVRM10
                 dst.RenderQueueOffsetNumber = mtoon.Definition.Rendering.RenderQueueOffsetNumber;
 
                 // rim
-                dst.ParametricRimColorFactor = mtoon.Definition.Rim.RimColor.ToFloat3();
+                dst.ParametricRimColorFactor = mtoon.Definition.Rim.RimColor.ToFloat3(ColorSpace.sRGB, ColorSpace.Linear);
                 if (mtoon.TextureIndexMap.RimTexture.HasValue)
                 {
                     dst.RimMultiplyTexture = new TextureInfo { Index = mtoon.TextureIndexMap.RimTexture.Value };
diff --git a/Assets/VRM10/Runtime/UnityExtensions.cs b/Assets/VRM10/Runtime/UnityExtensions.cs
index 936d2bcf8..b2c7dc1ee 100644
--- a/Assets/VRM10/Runtime/UnityExtensions.cs
+++ b/Assets/VRM10/Runtime/UnityExtensions.cs
@@ -273,11 +273,6 @@ namespace UniVRM10
             return new float[] { v.x, v.y, v.z, v.w };
         }
 
-        public static float[] ToArray(this Color c)
-        {
-            return new float[] { c.r, c.g, c.b, c.a };
-        }
-
         public static void ReverseZRecursive(this Transform root)
         {
             var globalMap = root.Traverse().ToDictionary(x => x, x => PosRot.FromGlobalTransform(x));