Scrolling my background Unity 5

Hello Community ,

So i m stuck , i can't scroll my background automaticly when i use this C# Code , I add it in a Quad component :

 void Update()
    {
  
  
  
            Vector2 offset = new Vector2(speed_move * Time.deltaTime, 0.0f);
  
            GetComponent<Renderer>().material.mainTextureOffset = offset;
         
  
    }

Can u help me please , i m a beginner in Unity Scripting :)