If you do the color change process (material.color) in Update(), it somehow goes through.

using UnityEngine;
using UnityEngine.UI;
using System.Collections;

public class BattleMain: BattleBase {

    protected int_sceneTask;
    // public GameObject prefab=(GameObject)Resources.Load("Object/MassTile");
    publicGameObject prefab=null;
    public GameObject[,] pass = new GameObject[15,15];
    intisk;
    intjsk;
    // Use this for initialization
    void Start() {

        // Load prefabricated to place 
        // GameObject prefab=(GameObject)Resources.Load("Object/MassTile");
        // Specify the object from which to place it 
        GameObject stageObject=GameObject.FindWithTag("Stage");
        //// tile arrangement
        for(inti=0;i<15;i++){
            for(int j=0;j<15;j++){


                Vector3tile_pos = new Vector3(
                    0+prefab.transform.localScale.x*i,
                    0,
                    0+prefab.transform.localScale.z*j

                    );

                if(prefab!=null){
                    // prefabricated replication 
                    GameObject instant_object = Instantiate(prefab, tile_pos, Quaternion.identity) as GameObject;
                    // attach a replicated prefabricated under the generator 
                    instant_object.transform.parent=stageObject.transform;
                    pass[i,j] = instant_object;
                }
            }
        }
        int Event=Random.Range(4,7); // Install event mass at random
        for(intp=0;p<Ivent;p++){
        intiRandNum=Random.Range(0,14);
        int jRandNum = Random.Range(0,14);
        mass[iRandNum,jRandNum].GetComponent<Render>().material.color=newColor(0.2f,0.8f,0.9f,0.5f);
        }


    }


    // Update is called once per frame

    void Update() {
        mass[5,5].GetComponent<Render>().material.color=newColor(0.0f,0.0f,0.0f);
        Debug.Log(pass[5,5].GetComponent<Render>().material.color);
        class[1,5].GetComponent<Render>().material.color=newColor(0.2f, 0.8f, 0.9f, 0.5f);
        Debug.Log(pass[1,5].GetComponent<Render>().material.color);
    }


}